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2016
TECHNICALSUMMARIES•
WWW.SPIE.ORG/PA

Beijing International Convention Center,
Beijing, China
Conferences:
12–14 October 2016

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1

GENERAL CHAIRS:

RobertLieberman
SPIE President,
Lumoptix (USA)Guangcan Guo
COS President,
University of Scienceand Technology ofChina (China)

SPONSORED BY:

CONTENTS:COOPERATING ORGANIZATIONS:
Tsinghua University
Peking University
University of Science andTechnology of China
Zhejiang University
Tianjin University
Beijing Institute ofTechnology
Beijing University of Posts
and Telecommunications
Nankai University
Changchun University of
Science and Technology
University of Shanghai for
Science and Technology
Capital Normal University
Huazhong University of
Science and Technology
Beijing Jiaotong University
Shanghai Institute of Optics
and Fine Mechanics, CAS

Changchun Institute of
Optics, Fine Mechanics andPhysics, CAS
Institute of Semiconductors,
CAS
Institute of Optics andElectronics, CAS
Institute of Physics, CAS
Shanghai Institute ofTechnical Physics, CAS
China Instrument and Control
Society
Optoelectronics Technology
Committee, COS
SPIE-China Committee
Japan Optical Society
Korea Optical Society
Australia Optical Society
Singapore Optical Society
European Optical Society

10016:

High-Power Lasers and Applications VIII .  .  .  .  .  . 310017:

Semiconductor Lasers and Applications VII.  .  . 20

10018:

Advanced Laser Processing andManufacturing. .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 33

10019:

Optoelectronic Devices and Integration VI. .  .  . 38

10020: Optoelectronic Imaging and Multimedia
Technology IV. .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 51
10021:

Optical Design and Testing VII.  .  .  .  .  .  .  .  .  .  .  .  .  .  . 65

10022: Holography, Diffractive Optics, andApplications VII.  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 85
10023: Optical Metrology and Inspection for
Industrial Applications IV .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 110
10024: Optics in Health Care and Biomedical
Optics VII.  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 130
10025: Advanced Sensor Systems andApplications VII.  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 175
10026: Real-time Photonic Measurements,
Data Management, and Processing II.  .  .  .  .  .  .  . 190
10027: Nanophotonics and Micro/Nano Optics III.  .  . 203
10028: Plasmonics II.  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 216
10029: Quantum and Nonlinear Optics IV. .  .  .  .  .  .  .  .  .  . 227
10030: Infrared, Millimeter-Wave, and Terahertz
Technologies IV .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 242

SUPPORTED BY:
China Association for Science and Technology (CAST)
Department of Information of National Nature Science
Foundation, China (NSFC)

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Conference 10016:
High-Power Lasers and Applications VIII
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10016 High-Power Lasers and Applications VIII

10016-1, Session 1

10016-3, Session 1

Progress on development of two-micron
solid-state laser for space-based remotesensing of wind and carbon dioxide

Research of high-power all-solid-statelaser and its applications in laser cutting
and laser processing

Upendra N. Singh, Mulugeta Petros, Tamer F. Refaat, Brian
M. Walsh, Jirong Yu, Michael J. Kavaya, NASA LangleyResearch Ctr. (United States)

Xue-Chun Lin, Institute of Semiconductors (China)

The societal benefits of improved weather forecasting and severe
weather warning, and better understanding of climate change
through identification of global carbon dioxide sources andsinks led to the desired NASA space missions of global wind andcarbon dioxide measurements. Studies of both desired missions
led to laser remote sensing solutions. The favored solutions
for wind and carbon dioxide are pulsed hybrid Doppler lidar
and Integrated Path Differential Absorption lidar, respectively.
NASA LaRC identified the desired pulsed laser attributes andwavelength regions for the coherent-detection portion of thepulsed hybrid Doppler and for the carbon dioxide laser remotesensors. NASA Langley Research Center (LaRC) has a long
history of developing pulsed 2-micron lasers. From fundamental
spectroscopy research, theoretical prediction of new materials,
laser demonstration and engineering of lidar systems, it has beena very successful progress spanning around two decades. This
presentation will cover the 2-micron laser development fromearly research to current state-of-the-art instrumentation andprojected future space missions. This applies to both global windand carbon dioxide active remote sensing.

10016-2, Session 1

High-power DUV lasers for material
processing
Toshio Mimura, kouji Kakizaki, Hiroaki Oizumi, Junichi
Fujimoto, Takashi Matsunaga, Hakaru Mizoguchi,
Gigaphoton Inc. (Japan)
A frontier in laser machining has been required by material
processing in DUV region because it is hard to get high powersolid-state lasers in this spectral region. DUV excimer lasers are
the only solution, and now the time has come to examine the
new applications of material processing with DUV excimer lasers.
We have developed three types of DUV excimer lasers. The
first is an injection-locked 193 nm excimer laser of 120 W with
an ultra-narrow spectrum below 0.3 pm. The excimer lasers at
193nm as well as 248nm have been used in the semiconductor
manufacturing for long years, and have field-proven stability
and reliability. One of the important features will be the ability
to support green operations while improving performance.
The second is a high power 351 nm laser with free spectrum
operation. A newly developed excimer laser of 450 W with low
cost of ownership is applied to the new annealing process of FPD
successfully. It can be highly reliable, because it was designedon the DUV excimer laser for semiconductor manufacturing. The
third is an 193 nm “hybrid” laser, which is the combination of asolid-state seed laser and an excimer laser amplifier. High lightharvesting efficiency and high coherence of the hybrid laser has
been achieved, which has M2 value of 1.6, and an average powerof 110 W with three-pass amplifications. An interference exposure
test demonstrated the high beam quality. The high photon
energy of 6.4 eV at 193nm is expected to interact directly withthe chemical bond of hard-machining materials, such as CFRP,
diamond and reinforced glasses. We will report the latest resultsof performance of these high power DUV lasers and material
processing.

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High-power all-solid-state laser has the significant advantages ofsmall size, light weight, high efficiency, good beam quality, highreliability, and so on. It was widely used in scientific research,
industrial processing, military and other fields. Laser processing
with high precision, small deformation, high speed has become
one of the most advanced processing technologies.
All-solid-state light source laboratory focuses on the researchof high-power all-solid-state laser and its applications. A seriesof key technologies of high efficient pumping, depolarizationcompensation, cascade amplification, high beam quality control,
and fiber coupling were broken through. In 2012, we successfully
achieved 7.13kW laser with electro-optical efficiency of 18.4% andbeam quality of 50.3mm • mrad through master oscillator power
amplifier. Using orthogonal dual acousto-optic Q-switching,average output power of 1023W quasi-continuous laser with
82ns pulse width, 20kHz repetition rate was generated. The
high-power all-solid-state lasers were successfully used in laser
welding, cladding, quench, cleaning and other fields. Cooperation
with domestic brand Chery Automobile, laser welding in
critical components of CVT automatic transmission has beensuccessfully used in the new Chery Tiggo SUV. The processing
effect is good. Cooperation with the world’s third-largest oil
supplier Weatherford, the laser cladding of the drilling unit was
carried out. The quality of laser cladding is very good. This is thefirst time that this kind of components developed and producedby China instead of Europe and America.

10016-4, Session 1

Application of adaptive optics in laser
weaponDong Zhao, Xiaofang Zhang, Beijing Institute ofTechnology (China)
In recent years, more and more countries pay attention to laser
weapons in military research, the laser weapons era has arrived,
but on the one hand, the heat deposition of laser weapons
cavity medium causing laser temperature uneven results inthe wavefront heat aberration,which will lead to the decline of
the quality of light; On the another hand, it is the atmosphericeffects on laser weapons, when the light beam transmitted
through the atmosphere, besides atmospheric absorption andscattering,the atmosphere turbulence disturbance will also cause
the beam wavefront aberration and scintillation effect, laser beam
wavefront aberration made by the two aspects severely affect theperformance of laser weapons. Adaptive optics as an real-time
wavefront compensation technology, with the advantages ofsimple structure, good correction effect, closed loop operationand so on, has been widely used for correction of wavefront
aberration in high-energy laser weapon system.This paper briefly
introduces the basic priciples of adaptive optics and the progressof domestic and foreign adaptive optical research for laser beam
quality correction, analyzes the key technology of laser weapon
adaptive optics, and finally summarizes some existing technicalproblems, and presents the application prospect of adaptive
optical system in the laser weapon#PhotonicsAsia

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Conference 10016:
High-Power Lasers and Applications VIII

10016-5, Session 1

10016-8, Session 2

Research of silicon solar cells’ minoritycarrier lifetime after irradiated by highpower laser

Low-threshold and high-efficiency solarpumped laser with Fresnel lens and agrooved Nd:YAG rod

Yu Zhang, Yunfei Li, Yanjie Li, Northwest Institute of
Nuclear Technology (China); Guomin Zhao, Min Sun Chen,
National Univ. of Defense Technology (China)

Zhe Guan, Changming Zhao, Suhui Yang, Yu Wang, Jieyao
Ke, Fengbin Gao, Haiyang Zhang, Beijing Institute ofTechnology (China)

Compared with traditional methods of energy supply, there isa great possibility to get a more remarkable enhancement of
conversion efficiency for laser power (of proper wavelength andintensity) beaming to silicon solar cells. However, it should benoticed that cells may be damaged by high power laser.Basedon the background, this essay explored high-power-laser’s
possible damage to the cells by analysing IV curves and minority
carrier lifetime, which was measured by open-circuit-voltagedecay method. Research shows that,for 30 seconds’ irradiation,
minority-carrier lifetime could be reduced when irradiated bylaser of over 5.5W/cm2 and the higher laser power density, themore degradation, which is similar to the variation trend of IV
curves. However, the degradation degree has a close relation
with equilibrium temperature. The prolonged illumination would
not bring about a more serious damage if the temperature hadalready reached a balanced point.

Solar has attracted widespread attention as relative
boundlessness of clean energy. Therefore, sunlight is considered
as a new efficient source for direct optical pumped solid statelasers. High-efficiency solar pumped lasers with low threshold
power would be more promising than semiconductor lasers
with large solar panel in space laser communication. Here we
report a significant advance in solar-pumped laser threshold bypumping Nd:YAG rod with a grooved sidewall. Two-solar pumped
laser setups are devised. In both cases, a Fresnel lens with asurface of 1.03m2 is used as the primary sunlight concentrator.
The gilding conical cavity with a liquid light guide lens is used as
the secondary concentrator to further increase the solar energy
concentration.

10016-6, Session 2

The research progress and application of
single-frequency laser (Invited Paper)
Haiwen Cai, Kang Ying, Dijun Chen, Fang Wei, Qing Ye,
Zhengqing Pan, Fei Yang, Ronghui Qu, Shanghai Instituteof Optics and Fine Mechanics (China)
The report gives an introduction about the research progressof different kinds of narrow-linewidth single frequency lasers,
including semiconductor laser, external-cavity diode laser, fiber
laser, etc. A review is also presented about the applicationof single frequency laser on the optical sensing and opticalcommunication areas.

10016-9, Session 2

Amplified spontaneous emission of adiode pumped cesium vapor laser withconsideration of deleterious processes

10016-7, Session 2

16.8W diode-pumped rubidium vapor
laser by using Brewster angle structure
Yannan Tan, Yimin Li, Chunyan Jia, Zhi Xu, Hu Shu, Jingwei
Guo, Wan-fa Liu, Dalian Institute of Chemical Physics(China)A high efficiency diode pumped alkali metal vapor laser isdemonstrated by using a gain cell with Brewster angle structure.
The one-trip transmittance of the laser in p-polarization is 97%,
which is improved effectively. A gain cell with length of 1 nm isused. It is filled with alkali metal rubidium vapor as gain medium
and methane with pressure of 600 Torr as buffer gas. Two diodelasers are used as the pump source with the power of 48 W andthe central wavelength of 780 nm. The linewidth of the diodelasers is narrowed to 0.1nm with volume bragg gratings. In orderto reduce the thermal effect of gain cell, a mechanical chopper isused to change the continuous pump laser to pulse output withpulse width of 1.85 ms , repetition frequency of 15 Hz and duty
ratio of 2.77%. The experiment is optimized by using the output
mirrors with output coupling rate of 41%, 58%, 76%. When thetemperature of the cell is 160 ?, using the output mirror of 76%,
the rubidium laser with wavelength of 795 nm and highest peak
power of 16.8 W is obtained. The optical to optical efficiency isabout 35%, and the slope efficiency is 44.2%.
4

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In the first setup, solar pumping a 6mm diameter Nd:YAG rod,
maximum laser power of 30.7W/m2 cw at 1064nm is produced,
which is higher than the reported record, the slope efficiencyof laser output power with solar power is 4.3%. In the second
setup, a 5mm diameter laser rod output power is 29.8W/m2
with a slope efficiency of 3.9%. The threshold power of 102W
is obtained, which is 38% lower than the former. At the sametime, the theoretical calculating of the threshold power andslope efficiency of the two setups has been established basedon the rate-equation of four-level system. The analysis results
are verified by using the finite element software (LASCAD) andexperiment. The experimental results agree with theoreticalanalysis. So the optimization of the geometry of the copper
cavity pumping system and resonator are useful for the design ofa miniaturization solar pumped laser.

Guofei An, You Wang, He Cai, Shunyan Wang, Kepeng
Rong, Hang Yu, Liangping Xue, Wei Zhang, JuhongHan, Hongyuan Wang, Jie Zhou, Southwest Institute ofTechnical Physics (China)
Diode pumped alkali laser (DPALs) provide a significant potential
for construction of high-powered lasers. A series of models havebeen established to analyze the DPAL’s kinetic process andmost of them are based on the algorithms in which the amplified
spontaneous emission (ASE) effect and deleterious processes
have not been considered. However, ASE is harmful in realizationof a high-powered DPAL since the gain is very high. Usually,
ASE becomes serious when the volume of the gain medium islarge and the pump power is high. In addition, alkalis are themost easily ionized atomic species, especially for rubidium andcesium. Under the condition of strong pump, the electrons will be
excited to the higher levels, such as n2D5/2,3/2 and (n+2)2S1/2,
by energy pooling collisions. Then, ionization processes including
photo-ionization and Penning ionization will occur in the
n2D5/2,3/2 and (n+2)2S1/2 levels resulting in decrease of thedensity of neutral alkali atoms. In this paper, a mathematic modelis introduced for examination of the kinetic processes of a diodepumped cesium vapor laser, in which the cesium vapor and thebuffer gases are beforehand filled in a sealed glass cell. ASE
effects along both the longitudinal and the transverse directions

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Conference 10016:
High-Power Lasers and Applications VIII
are taken into account in this model. The influence of deleterious
processes of energy pooling, photo-ionization, and Penningionization on the physical features of a DPAL is also studied at
the same time. It has been theoretically demonstrated that theASE effect can not be ignored in a high-powered DPAL system.
Basically, the conclusions we obtained in this study can beextended to other kinds of laser configurations.

10016-10, Session 2

Measurement of thermally-induced
distortion inside an alkali vapor with aquasi-Hilbert-transform algorithm
Wei Zhang, You Wang, He Cai, Juhong Han, Shunyan
Wang, Kepeng Rong, Hang Yu, Liangping Xue, Guofei
An, Hongyuan Wang, Jie Zhou, Southwest Institute ofTechnical Physics (China)
Diode-pumped alkali lasers (DPALs) have undergone rapid
development to become one of the most promising candidates
as very hopeful high-powered laser sources in recent years. Since
the gas-state laser medium has very low thermal conductivity
than that for a normal solid-state laser crystal, a very complicatedphenomenon of thermally-induced lens should be brought about
in a DPAL system. To evaluate such a complicated thermallyinduced lens, we measure the thermally-induced distortion
inside an alkali vapor cell by employing a quasi-Hilbert-Transform
algorithm in this study. A probe He-Ne beam propagates througha sealed cesium vapor cell which is placed in one arm of a MachZehnder interference setup. In the procedure, the extraction ofcosine term, fast Fourier transform (FFT), inverse fast Fouriertransform (IFFT), unwrapping process, and incline correction are
successively carried out to obtain the phase information. Then,
we deduce the distributions of focal lengths of a thermallyinduced lens from the wavefront distributions after eliminating
the effects of two cell side-windows. The results supply avaluable tool for design of a high-powered DPAL with good beam
quality.

10016-11, Session 2

Enhanced visible supercontinuum
generation in seven-core photonic crystal
fiber
Xue Qi, Sheng-Ping Chen, Tong Liu, Jing Hou, National
Univ. of Defense Technology (China)
The visible supercontinuum (SC) sources has played an importantrole in biomedical applications. However, the small core sizeof photonic crystal fiber (PCF) restrict the development ofhigh power SC by its small mode field area. In addition, thezero dispersion wavelength (ZDW) of the PCF with small core
diameter is usually below 1 ?m, which is far away from the 1.06
?m laser which is the most commonly used pump source. As
the ZDW of PCF shifts away from the pump, the intensity ofvisible light decreases correspondingly. To get an enhanced
visible SC with high output power, we promote a new technique,which involves an enhanced visible SC generation in sevencore photonic crystal fiber pumped by a high power 1016 nm
fiber laser. Muti-core PCFs offer a possibility of scaling up themode field area to a large extent without remarkable change indispersion properties, which show great potential in high power
SC generation. Using a 1016 nm fiber laser as the pump makes thepump is closer to the ZDW of PCF, which could raise the intensityof visible light. In this paper, we report an enhanced visible SC
generation ranging from 400 nm to 2300 nm in a seven-core PCF
pumped by a 1016 nm picosecond fiber laser. The visible light

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Follow us on:(350~800 nm) occupies 25% of the total SC power 24 W and thepower of the visible light is about 6 W.

10016-12, Session 3

Progress on high-power slab lasers(Invited Paper)
Qinjun Peng, Technical Institute of Physics and Chemistry(China)No Abstract Available

10016-14, Session 3

Pathway towards second harmonic
generation of a 100J 10hz diode-pumped
solid-state laser
Jonathan Phillips, Saumyabrata Banerjee, Michael Fitton,
Tristan Davenne, Paul D. Mason, Klaus G. Ertel, Thomas
J. Butcher, Jodie M. Smith, Mariastefania De Vido, Oleg
V. Chekhlov, STFC Rutherford Appleton Lab. (United
Kingdom); Martin Divoky, HiLASE Ctr. (Czech Republic);
Jan Pilar, Institute of Physics of the ASCR, v.v.i. (Czech
Republic); Andrew Lintern, Chris J. Hooker, Cristina
Hernandez-Gomez, STFC Rutherford Appleton Lab.
(United Kingdom); Tomas Mocek, HiLASE Ctr. (Czech
Republic); Chris Edwards, John L. Collier, STFC Rutherford
Appleton Lab. (United Kingdom)High energy and high average power nanosecond diode pumped
solid-state laser (DPSSL) systems operating at 100J-leveland 10 Hz pulse repetition rate are required for new scientificapplications, including material processing, advanced imaging
and laser pumping of short-pulse amplifiers. To increase thefunctionality of these DPSSL systems efficient second harmonic
generation (SHG) is a requirement. Recently, we have successfully
demonstrated a 100J-scale (beam size 75 mm square) DPSSL
based on cryogenic gas cooled, multi-slab ceramic Yb:YAG
amplifier technology. DiPOLE100 has been operated at 1 Hz
with pulse energy of 107 J and pulse duration of 10 ns with an
optical-to-optical conversion efficiency of 21%, when pumped
with 940 nm diode sources. Owing to the limited availability oflarge aperture non-linear crystals, we have used a scaled-down
10J DiPOLE cryo-amplifier system (beam size between 18 mm
and 10 mm square) operating at 10 Hz to investigate SHG of highenergy DPSSL systems. In this paper we will provide details of
the 100 J laser system and the salient performance parametersof the DiPOLE 10J laser system. We will present results of SHG
experiments for three candidate crystals, reporting conversion
efficiency (45% DKDP, 50% YCOB, 82% for LBO) at varying
intensity (>0.7 GW/cm2) levels, comparable to those expected
in a 100J-level system, and short-term energy stability in YCOB
and LBO for operation over 10 minutes. We present theoreticallycalculated temperature maps for both 10 J and 100 J operation
at 10 Hz and compare the merits of each crystal for energy andpower scaling. LBO represents the most promising candidate
for SHG of a 100J-scale DPSSL system, where recent advancesin crystal growth should soon overcome current limitations inavailable crystal size.

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Conference 10016:
High-Power Lasers and Applications VIII

10016-15, Session 3

An edge-pumped multislab amplifier for
Inertial Fusion Energy (IFE)Min Li, Xiaomin Zhang, Mingzhong Li, Xudong Cui,
Zhenguo Wang, Xiongwei Yan, Xinying Jiang, Jiangang
Zheng, China Academy of Engineering Physics (China)
We proposed a novel laser amplifier for inertial fusion energy(IFE) based on an edge-pumped, gas-cooled multi-slab
architecture. Compared to the face-pumped laser amplifiersfor IFE, this architecture enables the pump, coolant and laser
propagating orthogonally in the amplifier, thereby decouplingthem in space and being beneficial to construction of theamplifier. To satisfy the high efficiency required for IFE, highirradiance rectangle-waveguide coupled diode laser arrays are
employed in the edge-pumped architecture and the pump lightwill be homogenized by total internal reflection. A traverse
gradient doping profile is applied to the gain media, thus
the pump absorption and gain uniformity can be separately
optimized. Furthermore, the laser beam normal to the surfaces of
the gas-cooled slabs will experience minimum thermal wavefront
distortions in the amplifier head and ensure high beam quality.
Since each slab has its own pump source and uniform gain in
the aperture, power scaling can be easily achieved by placing
identical slabs along the laser beam axis. Our investigations
might provide an efficient and convenient way to design
amplifiers for IFE.

distance exceeding 100 m. For purpose of high-power optical
performance, alignment system for large-aperture laser beam
becomes essential parts of this kind of laser. General alignment
system for large-aperture laser beam is long in distance andlarge in volum because of taking near-field sampling technique.
With the development of laser fusion facilities, beam diameter,paths and components increase greatly. Therefore, the space
for alignment system is limited. General alignment system forlarge-aperture laser beam cannot meet the space requirements
anymore. A new alignment system for large-aperture laser beam
is designed to save space and reduce operating costs. The newalignment for large-aperture laser beam with a wedge is basedon far-field sampling technique. The wedge is placed behindthe spatial filter to reflect some laser beam as signal light foralignment. Therefore, laser beam diameter in alignment system issmall, which can save space for the laser facility. This alignment
for large-aperture laser beam has been demonstrated well on theSG-? Muliti-PW Facility. Comparing to general alignment system
for large-aperture laser beam, large-aperture lens, long distancelaser path and baffles with stepper motor is unnecessary for
proposed alignment system, which saves cost and space greatly.

10016-18, Session 4

Title to be determined (Invited Paper)
Guoying Feng, Sichuan Univ. (China)
No Abstract Available

10016-17, Session 310016-20, Session 4

High-power far-infrared optical parametricoscillator with high beam quality (Invited
Paper)

Correction of the phase distortion for
high-power laser by freeform shape mirror

Yingjie Shen, Chuanpeng Qian, Tongyu Dai, Xiaoming
Duan, Baoquan Yao, Harbin Institute of Technology(China)A high power ZnGeP2 (ZGP) optical parametric oscillator (OPO)
with good beam quality pumped by a Q-switched Ho:YAG laser
was demonstrated. The maximum output power of the ZGP OPO
with a four-mirror ring cavity was about 5.04 W around 8.1 ?mwith 83.9 W Ho incident pump power, corresponding to a slope
efficiency of 9.2 %. The ZGP OPO produced 36.0 ns far-IR pulse
laser in the 8.0-8.3 ?m spectral regions. The beam quality wasmeasured to be M2~1.6 at the highest output power.

10016-16, Session 4

Large-aperture laser beam alignment
system based on far-field samplingtechnique
Jiachen Zhang, Shanghai Institute of Optics and Fine
Mechanics (China) and Univ. of Chinese Academy of
Sciences (China); Daizhong Liu, Xiaoping Ouyang, Jun
Kang, Xinglong Xie, Shanghai Institute of Optics and Fine
Mechanics (China); Lei Gong, Shanghai Institute of Optics
and Fine Mechnics (China); Jian Zhou, Baoqiang Zhu,
Shanghai Institute of Optics and Fine Mechanics (China)
The inertial confinement fusion (ICF) facility is the largest
and most complex of high-power lasers, large-aperture laser
beams in these lasers, propagating from the master oscillator
driver to the target, interact with more than 100 near-field
optics and pass through several spatial filter pinholes over a6

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Gang Wang, Science and Technology on Solid State Laser
Lab. (China)
The wavefront can keep stable while the laser system is adjusted
well. Based on this characteristic, in order to improve thebeam quality, we suggest to make mirror of free-form surface
to compensate for the laser wavefront aberration. First, thetheory of aberration compensated with free-form shape mirror
is introduced, then through computer simulation, the mirror’scapability of is discussed, lastly, the mirror is used by laser system
which the average output power is 12.5KW. By the using of freeform shape mirror, laser’s wavefront, beam quality of farfield andintensity of nearfield are improved obviously: the intensity ofnearfield F is improved from 0.15 to 0.39; the wavefront’s PV is
improved from 6.3?m to 1.7?m; the wavefront’s rms is improved
from 2.0?m to 0.4?m; the beam quality of farfield ? is improved
from 5.25 to 1.8. Compared with deformable mirror of adaptive
optics, the free-form shape mirror has its own advantage: low
cost; with no increase to laser system complication; the freefrom shape mirror can be used to compensated for high orderwavefront aberration effectively.

10016-21, Session 4

Investigation on the formation of intense
fringe near Kerr medium slab in nonlinear
imaging
Yonghua Hu, Yaoqiong Qiu, Xue Peng, Hunan Univ. of
Science and Technology (China)
It is well known that hot-image can be produced by small-scale
scatterers. For phase-typed scatterers, hot-image and secondorder hot-image can be produced. However, when the numberof scatterer is larger than one, the interaction between the

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Conference 10016:
High-Power Lasers and Applications VIII
scatterered waves will lead to new nonlinear propagation results.
In this paper, the nonlinear propagation of flat-topped intenselaser beam through Kerr medium slab is investigated throughcomputer simulation, where the beam is modulated by twoparallel wirelike phase-typed scatterers with certain parameters.
We demonstrate that an intense fringe together with hot image
and second-order hot image can be formed when the distanceof the two scatterers is several millimeters. It is found that the
on-axis position of the plane of this intense fringe is in the middle
part between the exit surface of the Kerr medium slab and thesecond-order hot image plane. This intense fringe shows thefollowing basic properties: firstly, its intensity is apparently higher
than that of corresponding second-order hot image and can becomparable with that of corresponding hot image; secondly,
the distances between it and the in-beam positions of the two
scatterers are the same. Besides, the beam intensity profileshows that this intense fringe is the only prominent bright fringein its plane, and thus it is not a nonlinear image of any scatterer.
It is found that, as the phase modulation depth increase, theintensity of it increases at first and reaches its maximum when
the phase modulation depth is 3 rad, and then decreases, while
the corresponding scatterer distance basically keeps decreasing
slowly.

10016-13, Session Post

The influence of combined guiding effecton the beam quality in MOPA Nd:YVO4
lasersXingpeng Yan, Academy of Armored Force Engineering(China); Qiang Liu, Tsinghua Univ. (China); Xi Wang,
Department of Information Engineering, Academy ofArmored Forces Engingeering (China)
The effect of the combined guiding, the thermal induced guiding
and gain guiding, on the beam quality in Nd:YVO4 MOPA laser
is studied experimentally and theoretically. The beam quality
enhancement is achieved during the power-amplification process
in a 4-stage MOPA Nd:YVO4 MOPA laser. 195 W TEM00 modelaser is achieved while its beam quality enhanced from M2=3.2 to
1.2 after power amplification. This is an interesting phenomenon
since the beam quality is always deteriorated during the laser
amplification. To explain the phenomenon of beam quality
improvement, a theoretical model is established with the thermal
induced guiding effect and gain guiding effect is considered,and a nonlinear dynamical equation of the laser mode in laser
amplifier is derived. The wave equation is a Schrödinger-like twoorder nonlinear partial differential equation, and a symmetrical
split-step Fourier mothed is developed to analyze the wave
equation. Both experimental and theoretical results show thatthe combined guiding effect dominates the evolution of beam
quality in the insensitive pumping Nd:YVO4 MOPA lasers, andthe combined guiding effect can be employed to improve theperformance of beam quality in MOPA lasers.

10016-24, Session Post

63W output tandem-pumped thuliumdoped silica fiber laser at 1980 nm
Yingbin Xing, Wuhan National Lab. for Optoelectronics(China)We have demonstrated a high power and high efficiency thuliumdoped silica fiber laser using a cascade tandem pumping
method. A 1915nm Tm-doped fiber laser was used as a pumpsource for another Tm-doped fiber laser with the output powerof 63W at 1980nm, corresponding to the slope efficiency of~80%, which is the highest power to our best knowledge. And

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the 3dB bandwidth was 0.24nm. The 1915nm Tm-doped fiber
laser was pumped by 793nm diode laser and the slope efficiency
was 51%. The preform of double cladding Tm-doped fiber for the
tandem pumped fiber laser was manufactured by MCVD withusing the vapor-solution hybrid doping method. The fiber has a~25?m diameter, 0.098 NA(numerical aperture) core and 400?mdiameter, 0.46 NA inner cladding. In the tandem pumped fiber
laser, the resonant cavity consist of a pair of FBGs at 1980nm andthe homemade Tm-doped silica fiber. And the pigtail were angle
cleaved by ~8˚ to eliminate end reflection. The optimal active
fiber length was presented and it is found that when the lengthof homemade Tm-doped silica fiber was 7m, the efficiency was
the highest. The influence of Tm concentration and ratio of Tm
ion and Al ion on the efficiency was also explored. And it is foundthat the thulium-doped silica fiber with lower Tm concentrationand higher Tm:Al ratio had lower optical efficiency. Meanwhile,
the optimal fiber length became shorter.

10016-36, Session Post

Research on the effect of environment on
the energy coupling coefficient of 45#
steel under laser irradiation
Xiangyu Zhang, Guomin Zhao, Minsun Chen, Tianyu
Zhang, National Univ. of Defense Technology (China)
Experimental research on the energy coupling characteristicof 45# steel under mid- infrared CW laser irradiation is carriedout. In order to obtain the energy coupling coefficient, an
experimental system for reflectance measurement is set up by
an integrating sphere. The curves about reflectance along withthe temperature variation are measured respectively in nitrogenand air atmosphere. Based on the classical electromagnetic
theory and the Fresnel Formula, the theoretical value of theenergy coupling coefficient is derived under ideal condition.
Combined with the experimental phenomena and experimental
conditions, the qualitative analysis about the differences between
the theoretical value and experimental data is presented. The
mechanism about the variation of reflectance of 45# steel
under mid-infrared CW laser irradiation is also discussed. The
experimental results show that the energy coupling coefficientof 45# steel increased with temperature rising?but the curve inthe heating stage is not consistent with the curve in the coolingstage, which means that the change of the energy coupling
coefficient is not a reversible process. Additionally, the oxidation
reaction has an significant effect on the laser interaction with 45#
steel. In air atmosphere, the laser heating induces the oxidation
reaction of the 45# steel. As the temperature rises, the oxidation
reaction become more vigorous and the energy coupling
coefficient increases. However, in nitrogen atmosphere, thematerial is almost not oxidized. Accordingly, the energy coupling
coefficient in air is larger than that in nitrogen environment.

10016-46, Session Post

The outgassing characteristic research of
the silicone rubber in high-power laser
systemQipeng Wu, Lanzhou Institute of Physics (China)
The outgassing characteristic of the silicone rubber which is
the main material of non-metallic materials in high power laser
system was studied?outgassing rates of the silicone rubber
and the baked-out silicone rubber which was performed at
80? 4 hours were measured by the constant volume process
method and outgassing properties of them were analyzed by
the quadrupole mass spectrometer. The results show that theoutgassing rate of the silicone rubber and the baked-out silicone#PhotonicsAsia

7

Conference 10016:
High-Power Lasers and Applications VIII
rubber is 2.69?10-7Pam3s-1cm-2 and 6.47?10-8Pam3s-1cm2?respectively. All of them give out condensable volatile matterin vacuum. The outgassing rate and condensable volatile matterof the baked-out silicone rubber are less an order of magnitude
compared with the silicone rubber, and the outgassing rate of
the silicone rubber is less than 1?10-7Pam3s-1cm-2, which is fit for
non-metallic material of the high power laser system. This paper
also discusses the method of reducing the outgassing rate andcondensable volatile matter of the silicone rubber in high power
laser system.

10016-47, Session Post

Numerical modeling of three-level systemin ytterbium-doped photonic crystal fiber
laser
Cheng Zhou, Univ. of Jinan (China)
In order to investigate the power characteristics of the Yb-doped
PCF laser, we have represented a simple three-level systemmodeling based on a rate equation model. According to ourtheoretical modeling, the variation of the output power Pout via
the pump power Pp is theoretically studied, which agrees wellwith experimental data. Then, we have investigated the effects ofthe doped concentration of Yb ions, the length and the effectivemode field area of the PCF on the output power Pout of the Ybdoped PCF laser, respectively. The results show that the output
power Pout first increases and then decreases when the doped
concentration of Yb ions N0 increases and when the pump
power Pp and the length of the PCF L are constant. And the
optimal doped concentration Nm exponentially decreases when
the length L of the PCF increases and the slope of the optimal
doped concentration Nm also decreases when the length L of the
PCF increases. The output power Pout first increases and thendecreases when the length of the PCF L increases and when thepump power Pp and the doped concentration N0 are constant.
And the optimal length Lm of the PCF exponentially decreases
when the doped concentration N0 increases and the slope of thelength of the PCF also decreases when the doped concentration
N0 increases. The output power Pout linearly decreases when theeffective mode field area A increases.

10016-48, Session Post

Structural-optical integrated analysis
on the large aperture mirror with active
supporting
Zhiyuan Ren, jianqiang zhu, zhigang liu, Shanghai Instituteof Optics and Fine Mechanics (China)
Deformation of the large aperture mirror caused by the external
environment load seriously affects the optical performance of the
optical system, and there is a limit to develop the shape qualityof large aperture mirror with traditional supporting method. It iseffective way to reduce the optical mirror distortion with active
support method, and the structural-optical integrated method
is the effective means to assess the merits of the supporting forlarge aperture mirror. Firstly, we proposes a new support schemethat uses specific boundary constraints on the large lens edges
and imposes flexible torque to resist deformation induced bygravity to improve surface quantity of large aperture mirror. We
calculate distortion of the large aperture mirror at the edges ofthe flexible torque respectively with the finite element method;
secondly, we extract distortion value within clear aperture of themirror with MATLAB, solve the corresponding Zernike polynomial
coefficients; lastly, we obtain the peak-valley value (PV) androot mean square value (RMS) with optical-structural integrated
analysis . The results for the 690x400x100mm mirror show that
PV and RMS values within the clear aperture with 0.4MPa torques
8

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than the case without applying a flexible torque reduces 82.7%
and 72.9% respectively. The active supporting on the edge of thelarge aperture mirror can greatly improve the surface quality of
the large aperture mirror.

10016-49, Session Post

Design and fabrication of transmission
gratings with high diffraction efficiency
for pulse compression
Chaoming Li, Soochow Univ. (China)
Fused silica transmission grating plays an important role in
the ultra-short laser pulse compression system. Fused silica
transmission grating have the advantages of high diffraction
efficiency, high damage threshold, long life and no shelter,etc.
The design and fabrication of pulse compression grating areinvestigated theoretically and experimentally in this paper.
Rigorous coupled wave theory is used to design transmission
grating with trapezoidal microstructure. In the past, themicrostructure of transmission grating for pulse compression
is designed using rectangular structure. Through theoreticalanalysis, we find that the trapezoidal structure has better
diffraction efficiency than that of the rectangular structure. The
fused silica transmission grating based on trapezoidal structureis studied in the paper. The deep-etched fused silica transmission
grating (1250lp/mm) is fabricated by holographic lithography
and ion beam etching technologies. The aperture of transmission
grating is ?65mm, and its thickness is 1mm.The absolute -1stdiffraction efficiency is over 98%(@808nm). Experimental results
are coincident with the theoretical analysis.

10016-50, Session Post

Analysis research on transmitting andattenuating characteristics of non-lethal
laser weapon in the fog
Ning Shan, The Chinese People’s Armed Police
Force (China); liu xia, College of ElectromechanicalEngineering,Xi?an Polytechnic University (China); wangzhi jing, The Chinese People’s Armed Police Force (China)
Laser has been used in the military field widely because it has
some advantages, such as strong directional, fast speed, highenergy and flexible accurate. Non-lethal laser weapon does
not directly lead to death and equipped with destruction andthe destruction of the ecological environment. It has a broad
application prospect in the field of counter-terrorism ChuTu.
But the laser transmission should be affected by atmosphericenvironment. These will affect the operational effect of nonlethal laser weapons seriously. In this paper, the influence of fog
visibility of laser attenuation characteristics is studied using Mietheory based on analysis of the laser atmospheric transmission
theory. Different wavelengths laser attenuation coefficient in
the fog are simulated and calculated. Different wavelengths
laser’s Kim attenuation model are deduced when they propagate
in the fog. The relationship between attenuation coefficientand transmittance and the fog particle concentration and thetransmission distance of 532nm laser are studied by simulation.
The simulation results show that different wavelengths laser
attenuation was sharply increased with the decreasing of fog
visibility. Attenuation coefficient is as high as 40dB/km under thecondition of the fog. The laser transmittance with concentrationof fog drop speed greatly reduced. The laser transmittance is
40% in the 100m distance when the fog particle concentrationis 20/m3. And the laser transmittance is 10% in the 200m
distance. The laser transmittance is only 5% when the fog particle
concentration is 100/m3.

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Conference 10016:
High-Power Lasers and Applications VIII

10016-51, Session Post

10016-53, Session Post

Coherent combining efficiency
improvement based on a focusedconformal projection fiber laser array

Vortex beam based more stable annularlaser guide star

Dong Zhi, Yanxing Ma, Xiaolin Wang, Pu Zhou, Lei Si,
National Univ. of Defense Technology (China)

Hongyan Wang, Ruiyao Luo, Wenda Cui, Lei Li, Quan Sun,
Yulong He, Yu Ning, Xiaojun Xu, National Univ. of Defense
Technology (China)

In this paper, we present a series of coherent beam combining(CBC) experiments of home-made FCPS to show the coherent
combing efficiency improvement of FCPS comparing with CCPS
for the first time to the best of our knowledge. We setup a CBC
experiment system of two-dimensional home-made FCPS. We
choose three channels, each with an end-cap for laser output,
for the CBC experiment. Here we should point out that 20/400
fiber has greater power handling capacity, usually up to several
kW, than the fiber with small core diameter of 6/7 µm. A lenswith focal length of 2 m is used to focus the three laser beams
to the far field. The first part of the combined beam is imaged
by a CCD camera to observe the combined beam patterns.
The second part of the passing light is detected by a photonic
detector (PD) to provide feedback data. The signal processing
accomplished in a signal processor for phase-locking control anda field programmable gate array (FPGA) processor for end-cap/
tilt control. In our experiments, the filling factor is calculated
0.29, which is defined as the single beam diameter divided by the
distance of adjacent beamlets. Throughout the whole experiment,
single frequency dithering algorithm and SPGD algorithm areused to perform the phase-locking control and the end-cap/tilt
control respectively. Experiments results satisfy the numericalcalculations with system efficiencies above 80%. Comparing with
CCPS, the CBC efficiency of FCPS improves from 59.0% to 84.7%.

When generating laser guide star (LGS), sodium laser beam
travels up through the turbulent atmosphere before generating
LGS, resulting LGS spot wandering in the mesosphere. This
introduces complications when using a LGS and needs a tip-tilt
mirror in the laser launch optics to stabilize laser pointing. In
this paper, we presented a more stable annular LGS for adaptive
optics (AO) assisted ground based large telescopes. The morestable annular LGS is generated by a vortex beam rather thana Gaussian beam. In the uplink, a vortex beam tends to wander
more slightly than a Gaussian beam does in atmosphericturbulence. This would reduce spot wandering of annular LGS in
the mesosphere and ease the burden of uplink tip-tilt mirror. We
conducted numerical simulation to validate the feasibility andmerits of this concept. Our modeling follows three steps including
setting parameters of launch telescope and atmosphere,
simulating atmospheric propagation of a 20 W single-mode CW
laser, and giving saturation corrected fluorescent LGS basedon spatial intensity distribution of the arrival laser beam in themesosphere. We quantitatively estimated the wandering ofgenerated LGS and got a 37% reduced rms spot wandering ofannular LGS, which is beneficial to a closed-loop AO system.
Preliminary experimental results will also be presented. To
the best of our knowledge, it is the first time this concept isformulated.

10016-52, Session Post

10016-54, Session Post

Longitudinally-excited CO2 laser withshort-laser-pulse operating at highrepetition rate

Effect of nonlinearity saturation on hotimage formation in cascaded saturable
nonlinear medium slabs

Jianhui Li, Kazuyuki Uno, Tetsuya Akitsu, Univ. of
Yamanashi (Japan); Takahisa Jitsuno, Osaka Univ. (Japan)

Youwen Wang, Xiaohui Ling, Liezun Chen, Zhiping Dai,
Shizhuan Lu, Hengyang Normal Univ. (China)

A longitudinally excited CO2 laser has been developed with ashort laser pulse at high repetition rate. In our previous study, thecharacteristics of the CO2 laser were investigated at a repetition
rate of 1 Hz. In this study, the repetition rate of the CO2 laser wasincreased up to 300 Hz. The dependence of laser characteristics,
such as output energy, waveform and beam profile on therepetition rate were investigated. The discharge tube was madeof a 45-cm-long dielectric tube with an inner diameter of 9mm or 16 mm. The optical cavity was formed by a ZnSe output
coupler (reflectivity of 85%), and a high reflection mirror. The
mixed gas (CO2:N2:He=1:1:2) was flowed into discharge tube.
A fast rising voltage was applied to the discharge tube at 30
kV with a rising time of 0.2 micro-s. At a repetition rate of 300
Hz and a gas pressure of 3.4 kPa, the 9-mm discharge tube
produced a short laser pulse with an output energy of 17.3 mJ,
a spike pulse energy of 0.3 mJ, a spike width of 205 ns, and apulse tail length of 113 micro-s. The output power was 5.1 W. At ahigh repetition rate, the laser beam formed a strong point in thecenter of a ring shape. However, at a low repetition rate, the laser
beam formed a ring shape only. We thought that the laser beam
was concentrated by improving the repetition rate up to 300 Hz.

In high-peak-power laser system, nonlinear effect can cause hot
image to be formed, hot image can be so intense to damage
some components in its element chain. With the developmentof laser technologies, nowadays, the operating power of highpower lasers can reach enough high to result in the nonlinear
refraction index saturation of the media of the components.
We present analytical and simulative investigations on the
hot-image formation in cascaded saturable nonlinear medium
slabs based on spatial modulation instablity analysis and thestandard split-step Fourier method, to disclose the effect of
nonlinearity saturation on the distribution and intensity of hot
images. It is shown that, saturable nonlinearity does not change
the distribution of hot images, while may greatly affect theintensity of hot images, i.e., for a given saturation light intensity,with the intensity of the incident laser beam, the intensity of hot
images firstly increases monotonously and eventually reaches asaturation; for the incident laser beam of a given intensity, withthe saturation light intensity lowering, the intensity of hot images
decreases rapidly, even resulting in a few hot images too weak
to be visible. The results can help operators of high-power laser
system to lower risk of the optic elements damage of hot images.

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9Conference 10016:
High-Power Lasers and Applications VIII

10016-55, Session Post

Formation of hot image in an intenselaser beam through a saturable nonlinear
medium slab
Youwen Wang, Xiaohui Ling, Shizhuan Lu, Zhiping Dai,
Liezun Chen, Hengyang Normal Univ. (China)
In high-peak-power laser system such as Petawatt lasers, thelaser beam can be intense enough to lead to saturation of
nonlinear refraction index of medium. In additon, scattered lightby contaminants on optic components through nonlinear medium
can result in hot images which can be intense enough to damage
optic components, and therefore limit the output powers of
the system. We present analytical and numerical investigationsof hot image formation in an intense laser beam through asaturable nonlinear medium slab based on Fresnel-Kirchhoff
diffraction integral and the standard split-step Fourier method.
The analytical results are found in agreement with the simulation
ones. It is shown that, hot images can still form in an intenselaser beam through a saturable nonlinear medium slab; andthe saturable nonlinearity does not change the location of hot
images,while the nonlinearity saturation may lower the intensityof hot images; furthermore, for the laser beam of given intensity,
the intensity of hot images monotonously increases withthickness of the nonlinear medium slab, and the intensity of hot
images monotonously increases to reach a maximum at first, thenmonotonously decreases to reach a minimum with the phase shift
induced by the phase obscuration. Our results may be helpful toimprove operation safety of high-power laser syetem.

10016-56, Session Post

The numerical simulation of multi-pulse femtosecond laser
ablation on silicon are introduced in this paper. Firstly, thetwo-temperature model of the femtosecond laser interaction
with silicon including the band electron excitation, Auger
recombination effect and two photon excitation etc. are
introduced. The optical intensity inside the material which can bederived using the electric field obtained with Maxwell’s equations
in every optical half-cycle is used as an input condition to thematerial equations that describe the response of the material
to the intensity. By solving the material equations, parametersof the excited material, such as electron density and electron
temperature, are obtained.A single pulse laser damage threshold
is 0.26J/cm2 in the model by using 800nm femtosecond laser
and the heat accumulation effect is predicted with multi-pulses
shooting. What’s more, the irradiation of silicon with multiple
linear polarized femtosecond laser pulses at fluence close to
the damage threshold leads to the formation of laser-induced
periodic surface structures (LIPSS) on the surface. For laser
fluence near the ablation threshold, the finite-difference timedomain (FDTD) technique is used to calculate the electric field
distribution on the surface of the silicon and its evolution withthe formation of various nanostructures. It was found that the
ripples formed in the initial stage facilitate the ablation along thedirection perpendicular to the ripples, leading to the formation ofan elliptical ablation area. With increasing number of pulses, theablation area is gradually changed to a circular under the highfluence of femtosecond laser.

10016-58, Session Post

Experimental investigation of thethermally-induced core laser leakage inlarge-mode-area single-trench fiber
Lingchao Kong, Liangjin Huang, National Univ. of Defense
Technology (China); Shaoyi Gu, China Electronics
Technology Group Corp. (China); Jinyong Leng, Shaofeng
Guo, Pu Zhou, Zongfu Jiang, National Univ. of Defense
Technology (China)

Design of high-efficiency broadbandwidth unpolarized transmission
grating for femtosecond laser
Xinrong Chen, Chaoming Li, Soochow Univ. (China)
An unpolarized transmission grating with 1250lp/mm has been
designed at 780nm center wavelength with 740nm~840nm
bandwidth. By using the rigorous coupled-wave theory, computer
optimization shows that: by the proper choice of structure
parameters of groove depth and duty cycle, the first-orderdiffraction efficiency of a lossless-transmission surface-relief
grating with a rectangular surface profile can be made verylarge (>90%) simultaneously for light of TE and TM polarizations
incident near the Littrow angle. Be made of fuse silica, thisunpolarized transmission grating possesses high laser damage
threshold and therefore it is very suitable to apply in high-power
laser systems such as femtosecond laser. The process toleranceof structure parameters of groove depth and duty cycle are
analyzed in detail. As an important factor which is needed tobe considered in practical applications, the influence of incident
angle deviation to the Littrow angle for the first-order diffraction
efficiency is discussed and the adjustable range of incident
angle is present subsequently. Across the spectral region of
740nm~840nm, the process tolerance of groove depth is about
1.57um~1.61um and the process tolerance of duty cycle is about
0.54~0.62. The adjustable range of incident angle is 29.2°±1°.

10016-57, Session Post

Rippled area formed upon multi-pulse
femtosecond laser ablation on silicon

We demonstrate the thermally-induced core laser leakage insingle trench fiber (STF). The STF provides very high loss andpower delocalization of higher order mode (HOM) and therefore
maintain the single mode operation. However these properties
are investigated under low power situations. In this paper wepump the STF in a high power co-pumping fiber amplifier. The
maximum output power of 1022W was achieved with a slope
efficiency of 76%. Further increase the pump power led to the
output power decrease. Meanwhile, noise like power fluctuation
at ms level was observed when the power started to decrease.
However, no resonance frequency was observed in frequency
domain indicating the mode instability was not triggered. We
believe that it is the thermally-induced waveguide index profilechange due to the excessively heat load in the front section of
STF that leads to the failure of HOM suppression and the powerof FM was coupled into the HOM. However the heat load in therear section of STF was relatively low and the HOM started toleak into the cladding due to the bending loss. We provide asolution to mitigating this problem by pumping STF with pumplight of smaller absorption coefficient. A maximum power of1330W was achieved without power decrease via pumping with
905nm and 976nm pump light (the same amplifier). To our best
knowledge, this is the first demonstration of thermally-induced
core laser leakage in STF and the pertinent results can provide
significant reference for future optimization.

Zhiming Li, Jingsong Nie, Yuze Hu, Lei Wang, Electronic
Engineering Institute (China)

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Conference 10016:
High-Power Lasers and Applications VIII

10016-59, Session Post

10016-61, Session Post

Longitudinally-excited CO2 laser withmultiple laser tubes

Thermal effects of the gradient doping
gain fiber in all-fiber MOPA

Kazuyuki Uno, Tetsuya Akitsu, Univ. of Yamanashi (Japan);
Takahisa Jitsuno, Osaka Univ. (Japan)

Zichao Zhou, Xiaolin Wang, National Univ. of Defense
Technology (China)

We developed a longitudinally excited CO2 laser system that wasconstituted of multiple laser tubes and a single driver circuit. The
driver circuit had a high-voltage pulse power supply with the
input energy of 2.18 J, a spark gap, and a storage capacitor of
1400 pF. The driver circuit excited two laser tubes. 30-cm-longdischarge tubes with the inner diameter of 13 mm and 16 mm
were used. In the two-laser-tubes system at a gas pressure of 4.2
kPa (CO2: N2: He= 1: 1: 2), the 13-mm-tube produced a short laser
pulse with the output energy of 23.3 mJ, the spike pulse energyof 0.72 mJ, the spike pulse width of 140 ns, and the pulse taillength of 82.8 ?s. The 16-mm-tube produced a short laser pulse
with the output energy of 21.9 mJ, the spike pulse energy of 1.10
mJ, the spike pulse width of 200 ns, and the pulse tail length of
60.6 ?s. Therefore, in the two-laser-tubes system, the total output
energy was 45.2 mJ. In a one-laser-tube system with the input
energy of 2.18 J and the storage capacitance of 1400 pF at agas pressure of 4.2 kPa, the 13-mm-tube produced 29.6 mJ andthe 16-mm-tube produced 25.3 mJ. Therefore, in the same input
energy of 2.18 mJ at the same gas pressure of 4.2 kPa, the twolaser-tubes system was more efficiently than the one-laser-tube
system. Moreover, we investigated the three-laser-tubes system.

Thermal effect in the gain fiber is one of the main factors
which restrict the power improvement of high power fiber
amplifiers. Previous studies have shown that the thermal effectis closely related to the doping concentration in the gain fiber.
In order to reduce the temperature at the fusion point and the
maximum temperature of the gain fiber, we propose to use
doping concentration varying along the gain fiber as a method
to disperse the thermal effect of the gain fiber. A two stage
single frequency all-fiber-integrated MOPA is demonstrated,
the second stage of which has a hybrid gain fiber composed ofhigh-doped and low-doped Yb fibers. The temperature of thegain fiber is measured by a thermal imaging camera. It is shownthat compared with the constant doping fiber, temperature in thegradient doping fiber is greatly reduced when the output powers
are approximately the same, especially at the fusion point. The
corresponding theoretical study also verifies the accuracy ofthe experimental results. Based on rate equation model andthermal conduction model, the thermal distribution and output
power of the fiber laser amplifiers with corresponding constantand gradient doping gain fiber in the experiment are simulated,which agrees well with the experimental results. Results indicatethat the gradient doping of the gain fiber is an effective way to
alleviate the thermal effect in high power fiber lasers.

10016-60, Session Post

Spectral temporal characteristics ofthe radiation Ba I by femtosecond laser
breakdown on the surface of aqueous
solutions
Yuliya S. Biryukova, Alexey A. Ilyin, Far Eastern Federal
Univ. (Russian Federation); Sergey S. Golik, Far Eastern
Federal Univ (Russian Federation); Michael Y. Babiy,
Vladimir Lisitsa, Yuriy Kulchin, Far Eastern Federal Univ.
(Russian Federation)
The characteristics of spectral lines of Ba I (413,2 nm and553,54 nm) femtosecond laser breakdown on the surface of anaqueous solution BaCl2•2H2O was investigated. The transition
probabilities 6s21S 0 – 5d6p 3D0 1 ? 6s21S 0 – 6s6p 1P0 1 for Ba I
lines for wavelengths 413,2 553,54 nm and nm, respectively. The
obtained experimental dependences of the intensities of spectral
lines of Ba I from the time of registration delay relative to thelaser pulse. Shows the change in the attitude of the populationof the 5d6p 3D and 6s6p 1P levels Ba I from time delay. All
experimental data were obtained on a laser complex SpitfirePro
40F, Spectra-Physics with a Central wavelength of 800 nm,
pulse duration 45 fs, pulse energy - 0,82 mJ. 800-nm beam isfrequency doubled in a nonlinear BBO crystal to produce the
400-nm laser pulses of duration ~100 fs. . ICCD cameras (PicoStar
HR, LaVision and PI-MAX3, Princeton Instruments) coupled with
2500i or 2300 Acton SpectraPro spectrographs were used asa detectors. The technique temporary gating was used, when agate delays were varied from 10 to 210 ns. The experimental data
were performed in the software package WinSpec 2.6.5.

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10016-62, Session Post

Theoretical study of transverse mode
selection with volume Bragg grating inlaser resonator
Jing Hu, Soochow Univ. (China)
Volume Bragg grating (VBG) can be used in resonator to control
the transverse distribution due to its excellent Bragg selectivity.
Kogelnik’s coupled-wave theory is used to analyze the VBG’s
angular selectivity, and the output modes of the volume Bragg
resonator are simulated using the fast Fourier transform (FFT)
method and the coupled-wave theory. In this paper, the volume
Bragg grating is inserted into a plane-parallel resonator, theintensity distribution and diffraction losses of TEM00, TEM10
and TEM20 are simulated, and the loss difference for different
modes at different angular selectivity of VBGs are discussed.
At the angular selectivity of VBG is of 3 mrad, the diffraction
loss for fundamental mode is of 6.3%, while the diffraction loss
for TEM10 mode the TEM20 are 19.8% and 32.7%, respectively.
Therefore, TEM10 and TEM20 can be easily suppressed if the gain
is between 6.3% and 19.8%, and a fundamental transverse modecan be obtained.
Besides, the simulation results show that the intensity distribution
profile of the transverse modes become smooth with theinsertion of VBG, but the diffraction losses of transverse modes
are increasing and the diffraction loss increases with theorder number of transverse modes increasing. Moreover, theloss difference between different modes is getting large withthe angular selectivity of the VBG. The higher loss difference
between different modes is good for transverse mode selection
so VBG with reasonable angular selectivity in laser resonator
will force the multi-mode to operate in a single transverse mode,
which may has potential applications in lasers.

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11

Conference 10016:
High-Power Lasers and Applications VIII

10016-63, Session Post

Output characteristics of diode-pumped
Yb:YAG mode-locked laser with a dualcore fiber
Yan Yan, Li Wang, Beijing Univ. of Technology (China)
The self-starting soliton generate in a dual-core fiber without any
external mode-locking mechanism with the numerical simulated
and demonstrated.The low-intensity light can be transferredto the other and ejected from the laser cavity in the nonlinear
coupling between the two cores.Then we propose and analyze
a diode-pumped Yb:YAG solid mode-locked laser based on an
dual-core fiber, at the same time, the higher intensity light keeppropagation and remains largely unaffected have contrasted, andthe impact of the cavity characteristics on output parameters
has analyzed in order to obtain a better application in the actual
experiment.

including polarization locked fundamental soliton, bound states,
condensed phase, soliton bunching, harmonic mode locking, anddifferent types of polarization domain wall square pulses andtheir harmonic mode locked counterparts have all been observedwith different pump powers and polarization states.These results
indicated that the microfiber-based graphene not only could act
as a saturable absorber but also could provide high nonlinearity,
which is favorable for the cross coupling between the two
orthogonal polarization components. It was worth to mention
that it is the first time to obtain the polarization domain wall
solitons in a mode locked fiber laser.

10016-66, Session Post

Formation of noise-like square-wave
pulses in a microfiber-based topologicalinsulator fiber laser
Jingmin Liu, Hebei Normal Univ. (China)

10016-64, Session Post

Study on variations of transverse
electromagnetic distribution after the
linewidth narrowing of a LD
Liangping Xue, You Wang, Wei Zhang, Hang Yu, Shunyan
Wang, Kepeng Rong, Hongyuan Wang, He Cai, JuhongHan, Guofei An, Jie Zhou, Southwest Institute of TechnicalPhysics (China)
Because there are different wavelengths in the gain curve of alaser medium, the transverse electromagnetic (TEM) distributionof a diffracted beam must be greatly affected by a plane
diffraction grating (PDG) or a volume-Bragg-grating (VBG)
with an intrinsic wavelength which might be somewhat different
from that of the peak value of the gain curve. In practical, sucha phenomenon will become complicated during the processof self injection locking (SIL) in narrowing the linewidth of ahigh-powered laser diode (LD). Thus, it is important to study
variations of the transverse electromagnetic distribution after
narrowing the linewidth of a LD from 1000 GHz to about 10100 GHz for realization of a high-powered diode pumped alkali
laser (DPAL). In this paper, we experimentally investigatedthe beam propagation factor (M2-factor) and the transverse
electromagnetic distribution of an output laser beam after the
linewidth narrowing by employing a PDG with the different
incident angles. Light emitted from a 1-bar LD was collimatedby a pair of cylindrical lenses along the slow-axis. The results
reveal that the transverse electromagnetic mode of the output
laser beam with the narrowed linewidth becomes worse andan obvious smearing can be observed after using a diffractive
element such as a PDG, which are thought to be harmful inimproving the pump uniformity and extractive efficiency. The
results should be significant in designing and constructing theoptical system of a high-powered DPAL. Until now, there havebeen no relevant reports to the best of our knowledge.

10016-65, Session Post

Research on polarization vector
characteristics in a microfiber-basedgraphene fiber laser
Mengmeng Han, Hebei Normal Univ. (China)
We experimentally investigated the polarization vector
characteristics in an Er-doped fiber laser based on graphene thatwas deposited on microfiber. A rich variety of dynamic states,

12

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We have demonstrated the formation of noise-like squarewave pulses in an Er-doped fiber laser for the first time, using a
microfiber-based topological insulator as a saturated absorber(SA), which guaranteed both excellent saturable absorption
and high nonlinearity. The pulse duration of the square-wave
pulses could be increased obviously from 1 to 5.4 ns when thepump power was increased from 212 to 284 mW while thecorresponding spectral bandwidths showed slightly change. With
the pump power fixed and the polarization controllers of intracavity adjusted, harmonic mode locking with different orders
could also be obtained. The pulse possessed a low temporal
coherence, which was demonstrated by its double-scaled
autocorrelation trace.

10016-67, Session Post

Experimental investigation of high-energy
noise-like pulses from a long-cavity
erbium-doped fiber laser
Kexuan Li, Beijing Univ. of Technology (China) andChinese People’s Armed Police Force Academy (China);
Heyang Guoyu, Jinrong Tian, Yanrong Song, Beijing Univ.
of Technology (China)
The high energy noise-like pulses (NLPs) were experimentallyinvestigated in a passively mode-locked erbium-doped fiber laser
with a long ring cavity by using nonlinear polarization rotation
technique. Large net normal group-velocity dispersion of thecavity is estimated as high as 6.46 ps2, which is beneficial toformation of high-energy pulses. With the total pump powerof 970 mW (the pump powers of forward pump and backward
pump are set at the value of 455 mW and 515 mW, respectively),a stable ultrahigh energy rectangular-shape pulse emission withthe pulse duration of 35 ns is observed. The energy of square
packet with a fundamental repetition rate of 141.6 kHz is ashigh as 840 nJ. The signal-to-noise is higher than 60 dB in RF
spectrum. The feature of NLPs is confirmed by the coherent spikeof autocorrelation trace. When the pump power is beyond 970
mW, the mode locking operation with fundamental repetition
rate cannot be achieved despite of the large range variationof polarization controller settings. However, the forth-orderharmonic mode locking can be observed, the square pulse
packet duration still remains at ? 35 ns. The experimental results
demonstrate that the ultrahigh energy NLPs is only realized at
the condition of special physical parameters and it is restrictedby the numbers of ultra short pulses within the envelope to someextent.

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Conference 10016:
High-Power Lasers and Applications VIII

10016-68, Session Post

Dynamic measurement of reflectance/
emissivity in mid-infrared band
Tianyu Zhang, Min Sun Chen, Houman Jiang, Xiangyu
Zhang, National Univ. of Defense Technology (China)
In order to measure the change of laser energy coupling
coefficient with temperature in mid-infrared wave band,
reflectance integrating sphere experiment system was designed
and set up. 915nm CW laser was used to heat samples andthe wavelength of probe laser is 3.8?m. Chopper and phaselocked amplifier were adopted in the system. Thermal imager
was used to measure and record the temperature of samples
during laser irradiation. The reflectance of steel and aluminum
plates to 3.8?m was measured during 915nm laser irradiation.
According to Kirchhoff’s law, the emissivity of opaque samples
is equal to the absorption rate, namely the coupling coefficient.
Thus, the emissivity of samples was obtained at the same time.
And radiation temperature measured by the thermal imager
was adjusted through the curves of emissivity. EDS analysis wasdone to investigate the change of elemental composition in thesamples respectively. The experimental results show that, theresults of reflectance and radiation temperature measured bythis system are relatively accurate. In the process of temperaturerising from 25 to 500 degrees, the color of steel plates turns
black, while the color of aluminum plates is basically unchanged.
When temperature reaches about 350 degrees, reflectance ofsteel decreases obviously with the increase of temperature, whilereflectance of aluminum is almost constant. The reflectance is
probably determined by the oxide in the surface of samples
which is consistent with the results of EDS analysis. Reflectancedecreases with the increase of the content of oxygen in thesurface. The reason of why the reflectance of aluminum is almost
constant is that aluminum oxide is not generate massively under
500 degrees.

10016-69, Session Post

Simulation of wavefront optimization
by volume Bragg grating inphotothermorefractive glass
Xiaojie Sun, Fan Gao, Xiang Zhang, Xiao Yuan, Soochow
Univ. (China)
Wavefront distribution becomes one of the important parameters
for high power laser systems, since it influences the beam quality,
the focusing property and the triple frequency conversion effectfrom 1053nm to 355nm of laser beams. Wavefront distortion canbe introduced by many factors, such as the surface of large-scale
optical elements, thermal effect in laser systems, etc. Currently,
the adaptive optics system and the traditional spatial filter areused to suppress the wavefront distortions in high power laser
system. However, both of them require large space and time tomaintain.
In this paper, optimization for the wavefront distortion basedon volume Bragg gratings (VBGs) recorded in photo-thermorefractive glasses (PTR) is simulated. A beam with different
wavefront distortions is the incident beam on VBGs at the Bragg
angle. The wavefront distribution of diffracted beam through two
orthogonal VBGs is simulated based on the angular spectrum
theory and Kogelnik’s coupled wave theory. Four VBGs withdifferent angular selectivity at 2.0mrad, 1.5mrad, 1.0mrad, and
0.5mrad are used to simulated and optimize the wavefront
distribution. The simulation results show that the wavefront
distribution can be optimized with the VBGs due to its angularselectivity. The PV value of wavefront distribution is reduced from
2.51? to 1.77?, 1.71?, 1.68?, 1.47?, respectively. And the RMS value
is reduced from 0.207? to 0.0946?, 0.0942?, 0.0940?, 0.0935?,

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respectively. The wavefront PSD shows the distortion of medium
and high frequencies can be filtered with the VBGs.

10016-70, Session Post

Detection of laser-induced damage on
fused silica with photo-acoustic method
Muyu Yi, Xiang Zhang, Xiao Yuan, Soochow Univ. (China)
Detection of laser-induced surface damage on fused silica andother optical components is important for high power lasers.
Since influenced by the subjective factors, the traditional methodof phase contrast microscope observation is difficult to obtainan accurate, consistent laser damage threshold of opticalcomponents. The method of photo-acoustic detection, based onchanges in the waveform and amplitude of acoustic signals, canobtain a real-time and low personal-error damage threshold of
optical components, which has potential applications in highpower laser development.
In this paper, we design a new photo-acoustic probe which is
Anti-Emi (Electron-Magnetic Interference), easy-adjusted andnon-damage for the samples. Based on the photo-acoustic
detection system, the damage processes of fused silica samples
are detected according to the rapid increase of the acoustic
signals. The samples are irradiated under the laser beam with thewavelength of 1064 nm and pulse width of 10 ns. Experimental
results show that the damage thresholds of fused silica samples
are 13.86 J/cm2 at the wavelength of 1064 nm and the pulse
width of 10 ns. The above work may provide an effective
technical support for the laser-induced damage detection.10016-71, Session Post

Optimization of key parameters of a laser
ablation ion mobility spectrometer
Kai Ni, Jianan Li, Binchao Tang, Yuan Shi, Quan Yu, Xiang
Qian, Xiaohao Wang, Graduate School at Shenzhen,
Tsinghua Univ. (China)
Ion mobility spectrometry (IMS) is an atmospheric pressure
detecting technique adept in real-time and on-line detection.
Molecules could be ionized by sets of methods including
radioactive ionization, electric field ionization, ultraviolet
ionization and so on. But these methods could not apply tometal. Laser ablation ion mobility spectrometry (LA-IMS) is a
new application which emphasize on metal detection with the
combination of IMS technology and laser ablation sampling.
In this work, with a home-made ion mobility spectrometer, weinvestigated copper sheet signal intensity in different electricfield. The migration characteristics of metal ions match theformula: l_d/K?1/E_d =t_dwhen the electric field intensity isstronger than 500v/cm. The relationship between signal intensity
and sampling angle (the angle between drift tube and thetangent plane of the sample) was studied. With the increasingof the sampling angle, signal intensity had a significant increase;
while the laser incident angle had no significant influence on it.
The signal intensity increased 140% when the sampling angle
varied from 0 to 45 degree with the angle between the drift
tube and incident laser beam keeping 90 degree. Influenceof the position of ion gate is also studied in this work. And
results indicated that ion gate should be more than 2.5 cm tosample point or no signal was acquired. SNR was improved by asubtraction of acquired signal with a background signal acquired
afore by opening the ion gate. After the subtraction, shockwave
and electrical field perturbation produced during the interaction
between laser beam and samples, two main noise of the signal
could be eliminated. We also found that the distance between
the boundary of the copper sheet and the sampling point has
influence on the signal intensity.
#PhotonicsAsia

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Conference 10016:
High-Power Lasers and Applications VIII

10016-73, Session Post

This work was supported by the National Natural Science
Foundation of China (Grant No. 61475057).

Influence of soft bonding layer material
viscoplasticity on thermal lens andaspherical aberration of high-power thindisk laser

10016-75, Session Post

New type of fiber mode stripper withquartz tubes

Mu Wang, Guangzhi Zhu, Xiao Zhu, Yufan Feng, Jiapeng
Gao, School of Optical and Electronic Information,
Huazhong University of Science and Technology (China)
and National Engineering Research Center for Laser
Processing (China)
An viscoplasticity model is developed to analyze the deformationof laser disk with pumping. The characteristic of soft bonding
material is described with Anand model. Transient analysis forlaser disk with pumping considering bond solder viscoplasticity
is within 100 hours. An finite element analysis software COMSOL
is applied. Soft solder in this model is indium. Thin laser disk
bonded to copper tungsten alloy, thermal expansion coefficientof which match with the crystal. In analysis back surface of laser
disk is separated to spherical part and aspherical part. Thus
thermal lens and aspherical OPD induced by laser disk back side
can be obtained. Result show that, after 100 hours, refraction
power of disk module with large pump spot(8mm diameter) willchange more, but for disk module with small pump spot(4mmdiameter), surface aspherical part will change more. This two
parameter is important for high power fundamental mode disklaser design.

Fiber cladding mode stripper is one of key devices in high-power
fiber lasers and high-power transmission fiber. We report a newkind of mode stripper using quartz tubes with etched dots on thesurface. We studied the waveguide property of the mode stripper
both the dots on the outer surface and on the inner surface ofthe tube. Then we produced some quartz tubes using green laser
for the experiments, which demonstrated that the new model
strippers can reduce the cladding light and improve the axial
temperature distribution obviously.

10016-22, Session 510016-74, Session Post

Recent advances in Raman fiber lasers(Invited Paper)

The design of thin disk laser multi-pass
amplifier

Yan Feng, Shanghai Institute of Optics and Fine Mechanics(China)Enmao Song, Guangzhi Zhu, Xiao Zhu, Jinbo Yu,
Wenguang Zhao, Huazhong Univ. of Science andTechnology (China) and National Engineering Research
Ctr. for Laser Processing (China)
Thin disk laser is a successful design for realizing high output
power, high efficiency, and good beam quality, simultaneously.
Typically, the thickness of the thin disk crystal is between 100
microns and several hundred microns. The diameter of the disk
is, depending on the desired laser power, between some mm anda few cm. The disk crystal is soldered on the CuW heat sink toprovide an effective support. The most important advantagesof the thin disk laser are efficient cooling and the possibilityof reducing thermal aberration, which will be better to sustain
good beam quality of seed laser after multi-pass amplification.
However, the thinner thin disk crystal only provides very small
single gain. The multi-pass amplification technology andregeneration amplification technology are widely used to improvethe energy extraction efficiency. Comparing with regenerative
amplification technology, multi-pass amplification structure canaccept laser pulses range from continue wave to femtosecond
wave and can be operated in burst mode At the same time,
the amplification structure avoids complicated electronicallycontrolled optical switch and improves average output power.
In this paper, a thin disk multi-pass amplification system isdesigned based on the conjugated double parabolic mirror
pumping thin disk laser module, which realizes 40 passes
transmitting through the thin disk crystal. The light transmission
matrix is used to optimize optical mode matching of seedlaser spot size and pumping spot size during the multi-passtransmission. At the same time, anti-stability of the thin disk
multi-pass amplification system and the aberration of output
laser beam are analyzed in deeply.
Acknowledgements

14

Yongqian Chen, Yuli Qiu, Xiao Zhu, Huazhong Univ. of
Science and Technology (China) and National Engineering
Research Ctr. for Laser Processing (China); Hailin Wang,
Huazhong Univ. of Science and Technology, (China) andNational Engineering Research Ctr. for Laser Processing(China); Guangzhi Zhu, Changhong Zhu, Lijun Qi,
Huazhong Univ. of Science and Technology (China) andNational Engineering Research Ctr. for Laser Processing(China)SPIE Photonics Asia·

Stimulated Raman scattering is an effective and efficientnonlinear frequency conversion process inside optical fibers. In
recent years, Raman fiber lasers have advanced greatly in termsof output power, spectral coverage, and field of applications.
New schemes of Raman fiber lasers are emerging with technicalinnovation and interesting new physics.

10016-23, Session 5

Recent development on high-power
tandem-pumped fiber laser (Invited Paper)
Pu Zhou, Hu Xiao, Jinyong Leng, Hanwei Zhang, Xueyuan
Du, Jiangmin Xu, Jian Wu, National Univ. of Defense
Technology (China)High power fiber laser is attracting more and more attention
due to its advantage in excellent beam quality, high electric-tooptical conversion efficiency and compact system configuration.
Power scaling of fiber laser is challenged by the brightnessof pump source, nonlinear effect, mode instability and so on.
Pumping active fiber by using high-brightness fiber laser insteadof common laser diode may be the solution for the brightness
limitation. In this paper, we will present the recent developmentof various kinds of high power fiber laser based on tandem
pumping scheme. According to the absorption property ofYtterbium-doped fiber, Thulium-doped fiber and Holmiumdoped fiber, we have theoretically studied the fiber lasers that
operate at 1018 nm, 1178 nm and 1150 nm, respectively in detail.
Consequently, according to the numerical results we have
optimized the fiber laser system design, and we have achieved(1) 500 watt level 1018nm Ytterbium-doped fiber laser (2) 100

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Conference 10016:
High-Power Lasers and Applications VIII
watt level 1150 nm Ytterbium-doped fiber laser, 100 watt level
Ytterbium/Raman hybrid fiber laser and 100 watt level random
fiber laser (3) 30 watt 1178 nm Ytterbium-doped fiber laser, 200
watt-level random fiber laser. All of the above-mentioned are
the record power for the corresponded type of fiber laser to thebest of our knowledge. By using the high-brightness fiber laser
operate at 1018 nm, 1178 nm and 1150 nm that we have developed,
we have achieved the following high power fiber laser (1) 3.5
kW 1090 nm Ytterbium-doped fiber amplifier (2) 100 watt level
Thulium-doped fiber laser and (3) 50 watt level Holmium -doped
fiber laser.

10016-25, Session 5

1-MW peak power 574-kHz repetition
rate picosecond pulses at 515 nm from afrequency-doubled fiber amplifierFeng Zou, Zi Wei Wang, Zhao Kun Wang, Yang Bai, Qiu
Rui Li, Jun Zhou, Shanghai Institute of Optics and Fine
Mechanics (China)
High-peak-power infrared and green picosecond pulses areimportant sources for laser machining, optical parametricoscillators, and so on. In this paper, we present the direct
amplification of 30-ps pulses at 574-kHz repetition rate by usinga large mode area rod fiber amplifier. A peak power of 2.3 MW
at 1030 nm is generated and converted into 1 MW green peak
power through second harmonic generation (SHG). Both infraredand green pulses exhibit diffraction-limited beam quality. The
amplifier is seeded by a SESAM mode-locked laser with 30-MHz
repetition rate. After a Yb-doped single-clad fiber pre-amplifier,an acoustic-optic pulse-picker is used to pick out pulses witha repetition of 574 kHz. To obtain high-peak-power output aswell as avoid the self-phase modulation (SPM), we take use offlexible single-mode ytterbium photonic crystal fiber (NKT DC200/40-PZ-Yb) and ultra-large-mode-area rod-type photonic
crystal fiber (NKT aeroGAIN-ROD-PM85). We also optimize
every stage’s gain to control the spectral width introduced by
SPM. Then second harmonic generation with a LBO crystal under
type-? temperature-tuned interaction is investigated. The highest
SHG efficiency is 60%. 1-MW peak power, 574-kHz repetition
rate picosecond pulses with diffraction-limited beam quality is
generated at 515nm.

10016-26, Session 5

Efficient 1.5-um Raman generation inethane-filled hollow-core fiber
Yubin Chen, Bo Gu, Zefeng Wang, QiSheng Lu, National
Univ. of Defense Technology (China)
Eye-safety fiber sources operating in 1.5 µm regions haveattracted considerable attentions in the past decade, due to theirextensive applications in the fields of communication, sensing,
medicine, scientific research, and so on. Due to the spectrum
broadening induced by varieties of non-linear effects in thesolid core fiber at high power, it’s a great challenge to achieveboth high peak power and narrow linewidth 1.5µm fiber sources,
which are required in some applications, with traditional Erdoped fibers or Er-Yb co-doped fibers. In contrast with solid corefibers, stimulated Raman scattering (SRS) of gas in hollow corefiber provide an effective method for obtaining both high peak
power and narrow linewidth 1.5µm fiber source. We demonstratehere, for the first time to the best of our knowledge, a both highpeak-power and narrow linewidth 1.5 ?m fiber gas Raman source.
Using a 1064 nm microchip laser as the pump source, pulses of~400 kW peak power, ~7.5 GHz linewidth, ~123 ps pulse duration,
1552.7 nm center wavelength are obtained with a 6 m ethane-

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filled negative curvature hollow-core fiber at 2 bar pressure by
SRS. Comparing with the 1.5 ?m Er-doped or Yb-Er co-doped
fiber laser, the peak power is increased 1~2 order of magnitude,
meanwhile the linewidth is decreased 1~2 order of magnitude. If
using a tunable pump source, this kind of fiber source can easily
achieve broad tuning range near 1.5 ?m.

10016-27, Session 5

A systematic analysis of nanosecond pulse
amplification in ytterbium-doped doubleclad fiber amplifiers by considering
inelastic scatterings and different
operation regimes
Mohammad Abdollahi, Malek Bagheri Haroni, Univ. of
Isfahan (Iran, Islamic Republic of); Mohammad J. Hekmat,
Isfahan Univ. of Technology (Iran, Islamic Republic of);Meisam Fakhari, Univ. of Kashan (Iran, Islamic Republicof); Narges Shahriari, Mohammad Kanani, Hosein
Normohamadi, Isfahan Univ. of Technology (Iran, Islamic
Republic of)Dynamic characteristics of Ytterbium-doped double-clad fiber
amplifiers during the amplification of nanosecond pulses havebeen extensively analyzed by a number of researchers and
Dr. Wang is considered the first pioneer in this field. Although
in his works he studied different aspects of this process,they are mainly limited to specific repetition rates (mainly
tens of kilohertz), input temporal pulse widths (mainly tensof nanoseconds), input pulse peak powers and input pulse
bandwidths (not mainly narrow bandwidths). Also effect of
input pulse shape on threshold of inelastic scatterings has notbeen analyzed, to the best of our knowledge, that’s a common
phenomena in some amplifiers. On the other hand, in some
applications we need specific pulse widths that are less thanten nanoseconds that’s comparable to the phonon lifetime orsome pulses with repetition rates of less than ten kilohertz that
require us to consider special aspects such as pumping andinelastic scatterings. In our work based on numerical modeling
we systematically discuss these parameters from temporalpulse widths to repetition rates and pumping configurations
and analyze when to consider inelastic scatterings and change
pumping configuration from CW to pulsed pumps. Also for
the first time, to the best of our knowledge, we shed lighton the effect of input pulse shape on threshold of inelastic
scatterings and importance of using pulse shaping methods tosuppress these detrimental effects. Our results can give a better
understanding of nanosecond pulse amplification in Ytterbiumdoped double-clad fiber amplifiers.

10016-28, Session 5

Theoretical and experimental analysisof double-pass ytterbium-doped fiber
amplifierPengfei Zhang, National Univ. of Defense Technology(China)We theoretically and experimentally demonstrated a double-passytterbium-doped fiber amplifier. First, we numerically analyze
the impact of pump regime and fiber length on the amplifier. In
our experiment, a laser seed with output power of ~100 ?W andwavelength of 1064 nm is amplified to 70.3 mW with a signal
gain of 28.5 dB. With this double-pass configuration, amplified
spontaneous emission (ASE) is effectively suppressed to morethan 30 dB. Comparing with single pass configuration, it is found#PhotonicsAsia

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Conference 10016:
High-Power Lasers and Applications VIII
that double-pass amplification configuration enhances the gain
coefficient and improves the signal-to-noise ratio.

consists of a single frequency seed laser based on ultra-shortcavity, two pre-amplifiers and a main amplifier.. A short pieceof polarization-maintaining active fiber with a core diameter of
30 um and a high pump absorption coefficient is adopted in themain amplifier. The slope efficiency of the main amplifier is about
80%. No sign of SBS is observed at the maximal power. The neardiffraction-limited beam quality is realized with M2 < 1.5. To thebest of our knowledge, this is the highest output power of single
frequency fiber amplifier based on all-fiber structure.

10016-29, Session 5

Passive harmonic mode-locking in amonolayer graphene-based long-cavity
fiber laser with high pulse energy
Xiaoying He, Fudan Univ. (China); Dongning Wang, China
Jiliang Univ. (China)
Passive mode-locking fiber lasers have attracted strong researchinterest during the past decade, especially in the context of
producing high repetition rate pulses with short duration andhigh energy. To obtain the higher repetition rate pulses, thepassive harmonic mode-locking (HML) technique has been
employed, in which the fiber laser operates at a multiple of its
fundamental frequency. The first experiment of the HML in an
Erbium-doped fiber laser was implemented in 1993 by Grudinin
et al. Up to now, many approaches have been reported in
producing HML by use of nonlinear polarization rotation (NPR)[4-5], nonlinear amplifying loop mirrors (NALMs), semiconductor
saturable absorber mirror (SESAM), carbon nanotubes SESAM
combined with nonlinear polarization evolution and graphene.
In all the aforementioned HML fiber lasers based on saturable
absorber, the maximum output pulse energy achieved is very low,
below 30 pJ. Such low energy pulses are liable to be distortedby the noise when propagating in the optical communication
system.
In this paper, we experimentally investigated a dispersionmanaged HML fiber laser based on the polymer-supportedmonolayer graphene film for high pulse power output. A larger
light-graphene interaction has been achieved by using the MMF
with a larger fiber core to replace the SMF, thus leading to alarge output pulse energy. Single pulse energies achieved at thefundamental, the 2nd and the 3rd harmonics are ~1.55, ~1.13, ~1.04
nJ, respectively, by the use of the dispersion-managed system
and large light-graphene interaction area to improve single pulse
energy. The stable 3rd HML is obtained with ~603 fs pulse width,
repetition rate of 20.26 MHz and SNR of 53 dB. With sufficientpump power, higher order of HML pulses of large energy would
be generated. Such large energy ultrashort pulses would makethe fiber laser proposed be a potential light source for fiber
access network, material processing, optical frequency metrology
and sensing.

10016-30, Session 5

Zebiao Li, South China Univ. of Technology (China);
Zhihua Huang, Honghuan Lin, Jianjun Wang, Feng Jing,
China Academy of Engineering Physics (China); Shanhui
Xu, Zhongmin Yang, South China Univ. of Technology(China)For Small power system and hundreds of watts system, gain
saturation is considered and increases mode instability (MI)thresholds. In fact, only signal power saturation is included andpump power saturation is neglected, which is small enoughrespect to signal power saturation numerically and has little
effect in these systems. However, for output power of multikW-class and 10 kW-class lasers, pump power saturation makes
a significant effect on calculation accuracy. Moreover, we use
a semi-analytical model considering pump power saturation
to compute mode instability threshold, ensuring computation
accuracy and speed.
State of the art, fiber of 20 µm diameter core hasn’t reached 10
kW in single mode regime. Linear cladding fiber (LCF) laser of
20 µm diameter core can generate 10 kW-class power pumped
at 915 nm without MI effect in theory. Compared with other MI
suppressing strategies, LCF improves heat profile of fiber bothtransverse and longitudinal direction. LCF smoothes the heat
profile with stronger pump absorption and decreases nonlinear
coupling coefficient by shrinking inner-cladding diameter, leading
to the MI threshold scaling. Vignetting effect can be alleviatedby reducing tapering ratio or increasing fiber length, noted that
915 nm pumping scheme need relatively long fiber compared tothat of 976 nm pumping scheme. Fiber manufacture tapering
inner-cladding and maintaining the fiber core uniform should be
developed for this kind of fiber. LCF having a significant effect on
MI need to be verified in experiment.

Phase modulation signals optimization
automatically for suppression of
stimulated Brillouin scattering

Long Huang, Pengfei Ma, Rongtao Su, Xiaolin Wang,
Hanwei Zhang, Pu Zhou, National Univ. of Defense
Technology (China)
Narrow-linewidth fiber lasers have wide and promising
applications in gravitational wave sensing, nonlinear frequency
conversion, laser radar, coherent beam combining and so on.
Particularly, all-fiberized single frequency fiber laser with linear
polarization is rather attractive due to its extreme narrow
linewidth, high polarization degree, compact configuration androbust property. The output power of single frequency fiber laser
oscillator is limited and by using cascade power amplification
scheme, single frequency linearly polarized fiber have realized
output power from several watts to several hundred watts in thepast decade. In the present work, a 400 W-level single frequency
fiber amplifier with linear polarization is demonstrated basedon the master oscillator power amplifier configuration, which
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Linear inner-cladding fiber amplifier
suppressing mode instability

10016-32, Session 5

All-fiberized single-frequency
polarization-maintained fiber amplifier
with record power

16

10016-31, Session 5·

Min Jiang, National Univ. of Defense Technology (China)
and Hunan Provincial Collaborative Innovation Ctr of HighPower Fiber Laser (China); Yang Ran, Rongtao Su, Pu
Zhou, National Univ. of Defense Technology (China) andHunan Provincial Collaborative Innovation Ctr. of HighPower Fiber Laser (China)
In high power narrow linewidth fiber amplifier system, phasemodulation of the signal laser into multiple laser-lines is oneof the common methods to suppress the stimulated Brillouinscattering (SBS) effect, which is the main limiting factor toachieve high power. In order to achieve optimal suppressing
effect, the multiple laser-lines should have equal symmetrical
amplitude. To the best of our knowledge, detailed studies of theefficient generation of equal amplitude symmetrical spectrum

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Conference 10016:
High-Power Lasers and Applications VIII
with a certain number of lines within a limited linewidth andlimited peak spectral power density have not been reported.
In this paper, we use the phase modulation signal,which is thesum of a finite number of sinusoidal signals with different initial
phases and different weights,to generate equal amplitude
symmetrical spectrum. The stochastic parallel gradient descent(SPGD) algorithm is introduced the first time to search forthe optimal initial phases and weights through iterations,thus obtaining the optimal modulation signal. We generatehomogeneous symmetrical spectra with 11 lines and 19lines within
2 minutes and 29 lines within 6 minutes. Simulation results showthat the method works well. Compared with other nonlinear
algorithm, the SPGD algorithm holds the advantage of easy
control strategy and rapid optimization process. Based on thismethod, the details of the spectrum can be controlled, such as
the linewidth of signal laser and the peak power density.

10016-33, Session 6

Recent progress on high-field physics(Invited Paper)
Baifei Shen, Shanghai Institute of Optics and Fine
Mechanics (China)
This talk is about recent theoretical and experimental progresson high-field physics in our group. It includes three parts. First,
the physics of relativistic vortex laser is explored. The conceptof high OAM (orbital angular momentum) physics is proposed.
High order harmonics, electron jet producing and reflection of
intense vortex laser are discussed. Second, the QED effects, X
and gamma ray radiation is studied. Third, recent experimental
progress is introduced. They are laser driven proton and heavy
ion acceleration, proton radiograph, positron production, andgamma ray production.

10016-34, Session 6

Interaction of high-power laser beams
with plasma in ICF hohlraum using the
FDTD method
Zhili Lin, Huaqiao Univ. (China)
In the indirect-drive Inertial confinement fusion (ICF) system,groups of laser beams are injected into a gold cylindricalhohlraum and plasma is stimulated with the ablation of the wallof hohlraum by the high-power pulsed laser beams. In our work,
the powerful finite-difference time-domain (FDTD) method isused to numerically examine the high-power laser beam injection
and propagation in the high-intensity plasma. With the developed
dielectric constant model of plasma, the Maclaurin series
expansion (MSE) is applied to implement the dispersive modelin the frame of FDTD method. The state-of-the-art approaches
for generating the laser beams with a variety of parameters suchas angles of incidence, temporal waveform, polarization stateand intensity pattern are presented and realized according to
the full utilization of the TF/SF source condition. Base on theprevious technologies, the quantitatively numerical analysis of
the energy scattering of laser beams from the vacuum-plasmainterface at the entrance hole of hohlraum and the propagation
characteristics of laser beams in the plasma are further
conducted and investigated. Results are obtained, illustrated
and discussed that are helpful for optimizing the laser beam
parameters for the ICF system.

10016-35, Session 6

Nonadiabatic electron dynamics inorthogonal two-color laser fields withcomparable intensities (Invited Paper)
JiWei Geng, Peking Univ. (China)
We theoretically investigate the nonadiabatic subcycle electron
dynamics in orthogonally polarized twocolor laser fields withcomparable intensities. The photoelectron dynamics is simulated
by exact solution to the 3D time-dependent Schrödinger
equation, and also by two other semiclassical methods, i.e., thequantum trajectory Monte Carlo simulation and the Coulombcorrected strong field approximation.
Through these methods, we identify the underlying mechanismsof the subcycle electron dynamics and find that both the
nonadiabatic effects and the Coulomb potential play very
important roles. The contribution of the nonadiabatic effects
manifest in two aspects, i.e., the nonadiabatic ionization rate andthe nonzero initial velocities at the tunneling exit. The Coulomb
potential has a different impact on the electrons’ trajectories fordifferent relative phases between the two pulses.

10016-37, Session 6

Studies on high-quality electron beams
and tunable X-ray sources producedby laser wakefield accelerators (Invited
Paper)
Ming Zeng, Horia Hulubei National Institute of Physics andNuclear Engineering (Romania) and Shanghai Jiao Tong
Univ. (China); Ji Luo, Min Chen, Shanghai Jiao Tong Univ.
(China); Zheng-Ming Sheng, Shanghai Jiao Tong Univ.
(China) and Univ. of Strathclyde (United Kingdom)
Intense femtosecond mid-infrared laser sources are attracting
broad interests due to their potentials for a variety of
applications. We propose to drive laser wakefield acceleration
with mid-infrared high power lasers to achieve both high charge
and high quality electron beams. In order to obtain high-quality
electron beam injections, we adopt the ionization injection
scheme with square-wave like bichromatic lasers (SWBL), which
are composed of a laser at the fundamental frequency (or 2.4um) as the driving laser of the wakefields and another at its third
harmonic frequency (or 0.8um) as the injection laser [Phys. Rev.
Lett. 114, 084801 (2015)]. The injection laser is a 10 fs, 0.8um
laser pulse, which can trigger intermittent ionization injections
by beating with the driving pulse. Based upon three dimensional
particle-in-cell simulations, we show the production of electron
beams with energy of ~700 MeV, energy spread of ~1% andcharge of ~50 pC by a SWBL laser pulse with the peak power of~80 TW. This proposal may pave a way for applicable high quality
laser wakefield accelerators.

10016-38, Session 7

Self-starting and ultra-stable femtosecond
fiber lasers for industrial applications(Invited Paper)
Zhigang Zhang, Peking Univ. (China)
No Abstract Available

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Conference 10016:
High-Power Lasers and Applications VIII

10016-39, Session 710016-41, Session 7

Measurement and compensation schemes
for the pulse front distortion of ultraintensity ultra-short laser pulses

58W LD side-pump Nd:YAG picosecond
laser system at 1KHz with double length ofregenerative cavity

Fenxiang Wu, Yi Xu, Linpeng Yu, xiaojun yang, Jun Lu,
Wenkai Li, Yuxin Leng, Shanghai Institute of Optics andFine Mechanics (China)

Mingliang Long, Gang Li, Meng Chen, Beijing Univ. ofTechnology (China)

Pulse front distortion (PFD) is mainly induced by the chromatismof the employed lens-based beam expanders in femtosecond
high-peak-power laser systems, and it can temporally distort thepulse in the focus and therefore decrease the peak intensity. A
novel measurement scheme based on self-reference and secondorder cross-correlation technologies is proposed to directly
measure the PFD of ultra-intensity ultra-short laser pulses, which
is often associated with large beam size. The measurement
scheme is applied in an existed 200TW/1Hz/27fs Ti:sapphire laser
system, and the measured result of PFD is in good agreementwith the theoretical calculation, which also demonstrates thevalidity and feasibility of this measurement method. This method
can work not only without any extra struggle for the desiredreference pulse, but also largely reduce the size of the required
optical elements in the measurement, and it is the first time torealize the direct PFD measurement of ultra-intensity ultra-shortlaser pulses to our knowledge. In addition, in order to ensure
optimum performance of such ultra-short high-peak-power laser
systems, a simple combination of concave lens and parabolic
lens is also designed to compensate the PFD. According to thetheoretical calculation, the residual PFD of this laser system issmaller than 0.5fs after compensation, which can be ignoredwith respect to the pulse duration. Moreover, this direct PFD
measurement and compensation schemes can also be appliedin PW even 10PW ultra-short laser system with larger beam
diameter, in which the PFD issue is more significant generally forlarger lens-based expanders.

10016-40, Session 7

Accurate single-shot measurement of the
femtosecond pulse duration in the multipetawatt laser facility
Qingwei Yang, Xinglong Xie, Shuaixu Shi, Jianqiang Zhu,
Jun Kang, Ailin Guo, Meizhi Sun, Haidong Zhu, Shanghai
Institute of Optics and Fine Mechanics (China)
At the Shen Guang II (SGII) femtosecond 5PW laser facility,
the single shot femtosecond laser pulse diagnostic results is
affected by many factors, such as different attenuation under
different target energy condition, the beam divergence ofincident pulse, the distance between frequency doubing crystal
and detector in the autocorrelator, material dispersion of the
autocorrelator, etc., causing uncertainty in the measurementof the femtosecond pulse. In order to meet the requirementsof single shot femtosecond laser pulse diagnostic in the SG II
5PW laser facility, some methods have taken. For example, adispersion compensator is used to compensate the dispersion
of attenuation before autocorrelator, and an imaging system isused to overcome the effect of the incident pulse divergencein the autocorrelator. Through carefully design and a series ofexperiment, a single shot autocorrelator suit for the SGII 5PW
laser facility is achieved.

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An average power of 58W, pulse width of 40ps at 1KHz repetition
rate of Nd:YAG picosecond laser is reported. It used an etalon
to directly get pulse width of 135ps from Nd:YVO4 mode locked
laser in 1064nm, which repetition rate was 88MHz. When the seedpulses were injected into the double length of regenerative LD
side-pump Nd:YAG cavity at 1KHz repetition rate, the single pulse
energy was amplified to 3mJ, the pulse width was compressed to
99ps, beam quality of M^2 factor was 1.3. The single pulse energy
was amplified up to 58mJ, the pulse width was self compressed
to 40ps, beam quality of M^2 factor was approximately 3.5 after
single passing three stages of double high gain LD side-pump
Nd:YAG module. Beam pointing was about 40urad. The stability
for pulse to pulse RMS was less than 3%. A thin-film polarizer
and a quarter-wave plate was inserted into the regenerative
amplification cavity to let pulses double travel the same
geometric path basis on pulse polarization. Serrated aperture
were used in the amplification. That’s beneficial to decrease
the nonlinear effect for the high power in the crystal. High gain
LD side-pump Nd:YAG module could lead the pulse energy
amplify more and self compress the pulse width. Double lengthof regenerative cavity was used to enhance the optical cavity
length, it greatly decreased the laser’s volume and improved
stability of picosecond laser. It’s a nice way for high power
picosecond laser and the laser system would be more simple andsmaller.

10016-42, Session 7

The filamentation of femtosecond laser
pulse in air with various orders of superGaussian beam
Yuze Hu, Jinsong Nie, Lei Wang, Xianan Dou, Zhiming Li,
Electronic Engineering Institute (China)
The filamentation of femtosecond laser pulse in air are studied
numerically with various orders of super-Gaussian beam basedon the Nonlinear Schrödinger Equation. In order to investigate
the characteristics of filaments pertaining to filament length,
few-cycle pulses and supercontinuum which have high valuesof potential applications, we use three orders of super-Gaussian
beams in both temporal and spatial regimes as initial conditions
with the same energy, waist and pulse width. For the lengthof filaments, when the order of spatial super-Gaussian beams
becomes higher, the onset of filaments would be earlier while
the length becomes slightly shorter. With the order of temporalsuper-Gaussian beams becoming higher, the onset of filament
would be delayed and the length are slightly shorter too. Withfurther study, spatial and temporal orders of super-Gaussian playequal roles on the onset of filament, while the length is almost
dependent on the temporal order. For the few-cycle pulses
generation, after the filament is formed, the femtosecond pulse
will be divided into several shorter sub-pulses. The front part offew-cycle sub-pulse will be prolonged by increasing the spatial
order and the even shorter sub-pulses will be formed with thehigher temporal order. For the supercontinuum generation, thespectrum broadening seems to be tightly related to the temporalorder of super-Gaussian beam, which shows more intensive
broadening with higher temporal order. The underlying physics
behind these phenomena are optical Kerr-effect together withbackground energy reservoir in the spatial domain and self-phasemodulation together with plasma effect in the time regime.

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Conference 10016:
High-Power Lasers and Applications VIII

10016-43, Session 710016-45, Session 7

Mode-locked femtosecond allpolarization-maintaining erbium-doped
dispersion managed fiber laser based on anonlinear amplifying loop mirror

Integration of a directly chirped laser
source into a high-energy OPCPA system

Wenjue Wu, Yue Zhou, Ji Sun, Yitang Dai, Feifei
Yin, Jian Dai, Kun Xu, Beijing Univ. of Posts andTelecommunications (China)
In recent years mode-locked fiber lasers are well developed assome optical devices which can be used in a lot of fields such as
optical imaging, theoretical physics and high precision metrology.
In general the soliton laser is limited in output power because of
it usually worked in the anomalous dispersion regime, the wave
breaking effect lead the laser to reduce the energy[1]. The laser
can adopt dispersion managed cavity to overcome the limitationof energy, higher energy can be achieved as the net dispersion
is positive and near the zero. In addition The NALM has moreadvantages than NOLM, such as better control, shorter cavity
length, easier mode-locking[2-4]. If all elements and fiber incavity are polarization maintaining it will increase the stablility oftemperature and stress and the laser can work stably for a longtime.
In this paper, we proposed a mode-locked all-PM-Er fiber
laser base on NALM(nonlinear amplifying loop mirror). Thisconfiguration can better control and easier mode-locking. The
laser can generate 1.6 ps pulses with the energy of 1 nJ that canbe compressed down to 350 fs with the single mode fiber(SMF)
outside the cavity.

10016-44, Session 7

Stable linear SESAM femtosecond fiber
laser by use of Faraday rotator mirrors

Ran Xin, Univ. of Rochester (United States) and Cymer
LLC (United States) and ASML (United States); Jonathan
D. Zuegel, Univ. of Rochester (United States)
Chirped-pulse–amplification (CPA) technology is widely used
to produce ultra-short optical pulses (sub picosecond to
femtoseconds) with high pulse energy. A chirped pulse laser
source with flexible dispersion control is highly desirable as a CPA
seed. This work presents an all-fiber, directly chirped laser source(DCLS) that produces nanosecond, linearly-chirped laser pulses
at 1053 nm for seeding high energy CPA systems. DCLS produces
a frequency chirp on an optical pulse through direct temporalphase modulation. It provides programmable control for the
temporal phase, high pulse energy and diffraction-limited beam
performance, which are beneficial for CPA systems. A DCLS has
been built and its integration into a high energy OPCPA system
is experimentally demonstrated. DCLS produces a 1-ns, linearlychirped pulse with a 3-nm bandwidth by applying a ~1000-rad
quadratic temporal phase. This chirped pulse is amplified to 76
mJ in an OPCPA system and compressed to close to its Fouriertransform limit, producing an intensity autocorrelation trace witha 1.5-ps width. The intensity correlation trace corresponding
to the Fourier transform limit is 1.4 ps as calculated using
simulation. In this paper the DCLS concept is first described. Its
key enabling technologies are identified and discussed. These
include high-precision temporal phase control using an arbitrary
waveform generator, multi-pass phase modulation to achieve
high modulation depth, regenerative amplification in a fiber ringcavity and a negative feedback system that controls the amplifier
cavity dynamics. The key DCLS experimental results are thenpresented. These include the measured DCLS temporal phaseand its compression results.

Mohammad J. Hekmat, Asghar Gholami, Masood Omoomi,
Mohammad Kanani, Mohammad Abdollahi, Narges
Shahriari, Hossein Normohammadi, Isfahan Univ. ofTechnology (Iran, Islamic Republic of)Fiber based femtosecond lasers are rapidly growing in recent
years. For several applications, long stability of ultrashort pulsed
source is desirable. In this research by use of commercial fiber
components such as Batop SESAM, Thorlabs Faraday Rotator
Mirrors and nLight Er doped fibers, a stable femtosecond fiber
laser is achieved. In previous studies, PM fibers or Polarization
Controller (PC) was used to increase laser stability which are
replaced with Faraday Rotator Mirror at this research. Anotherstrength of this research, unlike the other studies in the field of
SESAM femtosecond fiber laser, no Kelly Sideband is observed in
output spectrum. With addition of Erbium-Doped fiber amplifier,the output power 100mW with 155 fs and 45.5 MHz repetition
rate is acquired.

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Conference 10017:
Semiconductor Lasers and Applications VII
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10017 Semiconductor Lasers and Applications VII

10017-1, Session 1

most of the so-called “green gap” where the emission efficiency
is low due to the higher indium content in conventional QW
optoelectronic devices. Our results provide an effective approachto overcome the “green gap”.

Recent progress in 1.3- and 1.5-um
waveband wafer-fused VCSELs (Invited
Paper)
Alexandru Mereuta, Andrei Caliman, Alexei Sirbu, Vladimir
Iakovlev, Dalila Ellafi, Alok P. Rudra, Ecole PolytechniqueFédérale de Lausanne (Switzerland); Philip Wolf,
Technische Univ. Berlin (Germany); Dieter H. Bimberg,
Technische Univ. Berlin (Germany) and King Abdulaziz
Univ. (Saudi Arabia); Eli Kapon, Ecole PolytechniqueFédérale de Lausanne (Switzerland)
Vertical cavity lasers emitting in the 1.3- and 1.5-µm wavebands
are important for a wide range of applications in opticalcommunications, sensing, illumination, optical pumping andspectroscopy. We discuss recent progress in the design,
fabrication and industrialization of such devices made by using
wafer fusion, which allows integration of GaAs-based DBRs with
InP-based active structures and an independent optimizationof the mirror and cavity properties before the fusion. Both the
GaAs-based mirrors and InP-based optical gain structures aregrown by MOVPE. The VCSEL structure comprises an InP-based
active region with InAlGaAs compressively strained quantum
wells (QWs) as the gain medium and tunnel junction aperturefor current and optical confinement, double-fused to two GaAs/
AlGaAs-based Bragg mirrors. By epitaxial growth, device design
and processing optimization 1.3- and 1.5-µm waveband VCSELs
emitting single mode power of 6-8-mW at room temperature andup to 3-mW at 80°C were demonstrated. Moreover, industriallymanufactured 10-Gb/s full wavelength-set VCSEL devices forcoarse wavelength division multiplexing systems with highyield and Telcordia-reliability have been developed. More recent
results showed that, by increasing the compressive strain in the
InAlGaAs QWs to 1.6% for higher gain, and by reducing the cavity
photon lifetime by decreasing the number of pairs in the top
DBR, it is possible to significantly improve both the static anddynamic performance of wafer-fused VCSELs emitting at 1.3-?m.
Thus, the modulation bandwidth was increased to 11.5-GHz andlarge-signal modulation response experiments show open eye
diagrams from 25 to 35 Gb/s for both B2B and after 10-km.

10017-2, Session 1

Green VCSELs based on InGaN QDs(Invited Paper)
Baoping Zhang, Yang Mei, Xiamen Univ. (China); Guoen
Weng, East China Normal Univ. (China); Jianping Liu,
Suzhou Institute of Nano-Tech and Nano-Bionics (China);
Werner H. Hofmann, Technische Univ. Berlin (Germany);
Leiying Ying, Xiamen Univ. (China)
Green VCSELs emitting in the spectral range from 491.8 nm to565.7 nm are demonstrated. These devices are featured with
low threshold current of less than 1 mA, CW lasing at room
temperature. The fabrication procedure includes laser liftoff ofsapphire substrate of the original epitaxial wafer, the removal ofhigh-defect GaN buffer to suppress the dislocation-induced lightscattering, metal bonding to increase the heat dissipation. Two
dielectric DBRs were adopted as the cavity mirrors.
For these VCSELs emitting at different wavelengths, thesame QDs active region was used while the wavelengths were
controlled by adjusting the cavity length, which is difficult foredge emitting lasers. Moreover, the emission wavelengths cover

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Green VCSELs are still at their initial stage of research. Up to now,
green VCSELs have been demonstrated under pulsed injection by
Nichia in 2011. The results presented here open up opportunities
to design and fabricate semiconductor green lasers with excellent
performance that may lead to wide-gamut, low consumption
power and compact displays and projectors. The VCSELs could
also be bonded on to Si for integration with other optoelectronic
devices/circuits.

10017-3, Session 1

980-nm ultra-high-speed VCSELs
exceeding 30-GHz Bandwidth (Invited
Paper)
Wissam Hamad, Werner H. Hofmann, Technische Univ.
Berlin (Germany)
With the increasing bandwidth demand of optical interconnects,
directly modulated VCSELs with ultimate speed ratings areneeded [1]. For serial 100 Gbps solutions today´s VCSELs have toincrease their high speed performance. Here we report about our
next generation devices.
The devices discussed here are an optimized version of our very
successful high-speed, temperature-stable 980 nm VCSELs
featuring a very short half-lambda cavity and a binary bottommirror with 32 pairs, levels were further optimized in order tominimize internal loss. Like previously, parasitics are controlled
by two oxide apertures and highly conducting current-spreading
layers. InGaAs MQW active layers with with strain compensated
GaAsP barriers were utilized for high differential gain. The 22-pair Al12Ga88As/Al90Ga10As top-mirror was replaced by a 18pair GaAs/Al90Ga10As mirror for lower photon lifetime, better
confinement and better heat extraction. The epi-structure wasgrown by IQE Europe.
As single-mode fitting showed poor overlap with the smallsignal modulation response data, a rate-equation analysis was
performed as suggested in [2]. Unlike longer-wavelength devices,
short-wavelength high-speed VCSELs emit multiple modes.
Therefore, a multi-mode rate equation analysis is necessary.
However, if the modes share the same carrier-reservoir, the multimode solution has the same algebraic shape. This is why singlemode rate-equation analysis usually works well even applied on
multi-mode devices. In case of non-linear effects like spatial holeburning, creating two or more coupled carrier reservoirs, different
solutions are possible.
The VCSELs showed modulation bandwidth around andexceeding 30 GHz. The common set of figures of merit isexpanded consistently to explain dynamic properties caused
by carrier fluctuations. This new model allows the consistentextraction of figures of merit and can explain mode-dependent
dynamics.
References[1] Hofmann, W., and Bimberg, D.: ’Abolishing copper
interconnects’, Stevenson, R. (Ed.) in Comp. Semicond., 18, pp.
30-34, 2012.
[2] W. Hamad, S. Wanckel, and W. Hofmann, “Small-Signal
Analysis of Ultra-High-Speed Multi-mode VCSELs,” IEEE J.
Quantum Electron., Submitted , March 2016.

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Conference 10017:
Semiconductor Lasers and Applications VII

10017-4, Session 1

10017-5, Session 1

Narrow-linewidth photonic microwave
generation based on an optically-injected1550-nm VCSEL subject to optoelectronic
feedback

Polarization and dynamical properties of
VCSELs-based photonic neuron subject tooptical pulse injection (Invited Paper)

Qing Liang, Li Fan, Ji-Yun Yang, Southwest Univ. (China);
Zhen-Zhen Wang, Southwest Univ (China); Zheng-Mao
Wu, Guang-Qiong Xia, Southwest Univ. (China)
Radio-over-fiber (RoF) has a promising application prospectin modern communications since it can effectively combine
the optical fiber communication and the wireless microwave
communication. As one of key techniques for supporting RoF,
the acquisition technique of photonic microwave has received
much attention in recent years. At present, several schemes
for photonic microwave generation have been demonstrated
including direct modulation, external modulation, optical
heterodyne, double mode beating frequency based on dualmode lasers of multi-segment integration, dual wavelength
beating frequency of dual-wavelength fiber lasers by
incorporating a delay interferometer and a saturated absorber,and so on. Each of these schemes mentioned above has its
distinctive advantages and limitations, and these limitations stillneed to be further improved.
In addition to above mentioned methods, the photonic
microwave generation technique based on the period-one (P1)nonlinear dynamics of optically injected semiconductor lasers
has also been paid more attention due to following advantages.
First, the microwave frequency generated by P1 oscillation is
widely tunable beyond the relaxation resonance frequency.
Second, single sideband (SSB) optical spectrum structure canbe achieved by adjusting the injection parameters, which has theadvantage of minimizing the microwave power penalty caused bychromatic dispersion of the optical fiber. Moreover, the opticallyinjected semiconductor laser system can be used as an AMto-FM conversion module to reduce the fading effects inducedby AM modulation in the RoF system. Even so, the generated
microwave usually has a relatively large linewidth and poor
frequency stability, which may limit its applications. As a result,further improvement methods have been introduced to obtainhigh performance and narrow linewidth photonic microwave.
We have noticed that the used semiconductor lasers in most of
relevant investigations on photonic microwave generation byusing the period-one (P1) nonlinear dynamics of optically injected
semiconductor lasers usually are edge emitting semiconductor
lasers (EELs). Compared with EELs, vertical-cavity surfaceemitting lasers (VCSELs) are promising devices with such unique
virtues as small size, low threshold current, compactness, singlelongitudinal-mode and so on. Based on this consideration, in
this work, we have experimentally demonstrated high-quality
photonic microwave generation based on the P1 dynamical state
output from an optically injected 1550 nm vertical-cavity surfaceemitting laser (1550 nm-VCSEL) subject to optoelectronic
negative feedback. The experimental results show that, underan optical injection with parallel polarization, a 1550 nm-VCSEL
can exhibit rich nonlinear dynamical behaviors such as stableinjection locking (SIL), P1, period-two (P2), chaos (CO) throughadjusting the injection strength and frequency detuning. Under
suitable injection condition, the 1550 nm-VCSEL can generatea photonic microwave signal with single sideband optical
spectrum structure, but the linewidth of the microwave signal isrelatively wide (on the order of MHz). After further introducing
optoelectronic negative feedback, the linewidth of the microwave
signal can be narrowed to 105.7 kHz (reduced to more than twoorders of magnitude). Furthermore, under the case that the
feedback strength is set at an optimized value, the frequency ofthe microwave signal can be tuned continuously within a certain
range through simply varying the injection strength.

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Shuiying Xiang, Aijun Wen, Hao Zhang, Jiafu Li, Xingxing
Guo, Xidian Univ. (China)
The polarization switching (PS) properties and nonlinear
dynamics of vertical-cavity surface-emitting lasers (VCSELs)
subject to orthogonal polarization optical pulse injections areinvestigated numerically based on the spin flip model. The
responses of VCSEL under the arrival of external stimuli of
orthogonal pulse injection are mainly discussed. The effects ofpulse width, pulse repetition frequency, pump current, injection
strength, as well as the frequency detuning on the PS properties
and nonlinear dynamics are considered. It is found that, the PS
can be obtained by the optical pulse injection. Moreover, thefrequency detuning induced PS can also be achieved for opticalpulse with given strength, width and repetition frequency.
The frequency detuning modifies the response properties
significantly. For negative frequency detuning, the optical pulse
injection cannot lead to PS. For positive frequency detuning,
different spiking patterns, limit cycle and chaotic dynamics canbe obtained under different operating condition of pulse widthand repetition frequency. In particular, under the condition of
external optical pulse injection with positive frequency detuning,many dynamics of biological neurons can be optically mimicked
successfully, such as phasic spiking, tonic spiking, phasic bursting,which extend the application of VCSELs for the emulation of the
dynamics of neuron. These simulation results are also similar to
those obtained by several experimental demonstrations of longwavelength VCSELs. The parameter regions leading to different
spiking patterns are further identified. Thus, the numerical modeland simulation results of VCSEL-based neuron are very usefuland interesting for the ultrafast brain-inspired neuromorphic
photonics systems.

10017-7, Session 2

Room-temperature continuous-wave
operation of GaN-based green laser
diodes (Invited Paper)
Jianping Liu, Suzhou Institute of Nano-Tech and NanoBionics (China)
We have demonstrated GaN-based green laser diodes with
output power of 58 mW under room temperature continuouswave operation, which is made possible since a low thresholdcurrent density of 1.8 kA/cm2 and a low threshold voltage of 4.5
V have been achieved.
The low threshold current density is attributed to improved
material quality of InGaN multiple quantum wells(MQWs), which
is a challenge for green LDs due to green gap problem, i.e.
reduced quantum efficiency in the green spectrum range. By
suppress the In-rich cluster and reducing growth temperature of
p-AlGaN:Mg cladding layer, the dark spot in green InGaN MQWs
is eliminated, and therefore the quantum efficiency of green LD
structures is improved by 4.5 fold.
However, when growth temperature is reduced, AlGaN:Mg layers
are found to have high electrical resistance since increased
carbon impurity exists and carbon acts as compensating donor
in AlGaN:Mg layers. By tuning MOCVD growth conditions tosuppress carbon concentration, the electrical resistance of lowtemperature grown AlGaN:Mg layers is reduced, and therefore
low threshold voltage is achieved for green LDs.
GaN-based green LDs are desired to replace solid state lasers
for laser display and pico-projectors. Therefore a great deal of#PhotonicsAsia

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Conference 10017:
Semiconductor Lasers and Applications VII
attention have been paid to improve their performance to meetthe demand.

10017-8, Session 2

Investigation of single lateral mode for852nm diode lasers with ridge waveguidedesignBaolu Guan, Chu Liu, GuoXin Mi, Yi Ru Liao, Zhenyang Liu,
Jianjun Li, Chen Xu, Beijing Univ. of Technology (China)
852nm Narrow linewidth lasers can be widely used in the fieldof ultra-fine spectrum measurement, Cs atomic clock control,
satellite and optical fiber communication and so on. Furthermore,
the stability of the single lateral mode is a very importantcondition to guarantee the narrow linewidth lasers. Here we
investigate experimentally the influence of the narrow ridge
structure and asymmetrical waveguide design on the stability
single lateral mode of an 852nm diode laser. According to the
waveguide theoretical analysis, ridge mesa etch depth (, related
to the refractive index difference of parallel to the junction) andridge mesa width (the narrower the more control force to loworder mode) are the main elements for lateral modes. In thispaper, we designed different structures to investigate and verify
major factors for lateral mode by experiment, and to confirm ourthought. Finally, the 5 ?m mesa ridge laser, 800nm etch depth,with groove structure obtains excellent steady single lateral mode
output by 150mA operating current and 30? temperature. The
optical spectrum FWHM is 0.5nm and side mode suppression
ratio is 27dBm with uncoated. The laser with 1mm cavity length
showed the threshold current of 50mA, a lasing wavelength of? = 852.6 nm, slope efficiency of above 70%. We accomplishedsingle lateral mode of ridge waveguide edge-emitting lasers
which can also be used as a laser source in the ultra-narrow
linewidth external cavity laser system.

10017-9, Session 2

To packaged 650nm red semiconductor
laser with transparent window
Zhen Zhu, Wei Xia, Shandong Huaguang Optoelectronics
Co., Ltd. (China)
In order to improve the characteristics of the AlGaInP/ GaInP red
semiconductor laser diode, we design an asymmetric cladding
structure, optimize the epitaxy growth condition and fabricate
a transparent window facet by zinc diffusion method. After chipprocess manufacture, the laser chip with 12-µm stripe is bonded
on TO18 package. Under continuous-wave (CW) operation
condition, the typical threshold current is 42 mA, the slope
efficiency is 1.12W/A, the wall-plug efficiency reaches 39.8%, andthe maximum output power reaches higher than 320mW. Also,
the character temperature reaches 75K.

10017-10, Session 2

830-nm InGaAs quantum-well lasers withvery low beam divergence
Bocang Qiu, Hai M. Hu, Weimin Wang, James Ho, ResearchInstitute of Tsinghua Univ. in Shenzhen (China); Wenbin
Liu, Langxing Kuang, Taishan Wang, Shujuan Wu, Raybow
Optoelectronics Ltd. Inc. (China)
We report on our design and fabrication of 830 nm high power
semiconductor lasers with extremely low beam divergence.
830 nm semiconductor lasers are widely used in digital
22

SPIE Photonics Asia·

printing and 3D sensing. Due to the intrinsic small size of theactive region in the wafer growth direction, laser beam from asemiconductor quantum well structure is highly asymmetric in
the two orthogonal directions. In many applications, particularly
in low cost applications, it is highly desirable that a laser has aroughly circular beam profile as this would greatly reduce thecost associated with beam shaping and packaging. Conventional
design by manipulating the waveguide thickness or/and the index
profile does enable one to achieve low beam divergence to someextent. However this approach not only has detrimental effects
on the other parameters such as threshold current, quantum
efficiency, but also quite often becomes impractical as thegrowth tolerance becomes too small. Here we propose a novel
approach in which by combining asymmetric waveguide and afeature called “pins” together, we are able to design an optimized
epi structure which not only produces a beam divergence of lessthan 16 °, but also has very good growth tolerance as well. Tested
devices show the beam divergence is as small as 13.5°, yet they
still retain very high slope efficiency of around 1.26 W/A and low
threshold current.

10017-27, Session 2

Directly-modulated laser-based 100G-PON
demonstration (Invited Paper)
Lilin Yi, Honglin Ji, Weisheng Hu, Shanghai Jiao Tong Univ.
(China)As the demand for broadband applications continues rising, lowcost and high capacity PON system has attracted more attention
to keep up with the increasing demand in the future accessnetwork. Recently, the IEEE 802.3 Ethernet Working Group has
already sponsored the discussion of next generation Ethernet
passive optical network (NG-EPON) to provide 25-Gb/s per
wavelength. In order to upgrade current 10-Gb/s PON to realize
the capacity of 100 Gb/s PON with 25 Gb/s per wavelength,a variety of experimental demonstrations have shown thefeasibility of 25-Gb/s per wavelength using the modulation
schemes of four-level pulse amplitude modulation (PAM-4) [1-3]or electrical duobinary (EDB) [4] or optical duobinary (ODB)[5] or non-return-to-zero on-off-keying (NRZ-OOK) [6] for highspeed transmission. However, different modulation formats
have different advantages and disadvantages. For PAM-4 andduobinary modulation schemes, high speed duobinary-to-binary
conversion circuit is required for the demodulation of such
advanced modulation formats. And for the ODB and NRZ-OOK
modulation schemes, high bandwidth transmitter and receiver are
required, which can increase the cost. In order to achieve higher
performance, these transmission schemes are always combinedwith the advanced digital signal processing (DSP) which
increases the technical complexity and the cost as well. Most of
the previous demonstration are based on the off-line processing,
therefore requires more time for the practical deployment.
In this paper, we demonstrate the first field trial a real-time
100Gb/s TWDM-PON system with 4?25-Gb/s downstream and4?10-Gb/s upstream transmission using 10G-class directlymodulated lasers (DMLs) and APD/PIN receivers. A single delayinterferometer (DI) is used to achieve frequency equalization
as well as chirp management to increase the high frequency
components of the system response and combat the chromatic
dispersion (CD) during the fiber transmission. Note that there
is no DSP applied for the whole system. Electrical clock/data
recovery (CDR) chips are integrated on the main board fordata generation, recovery and real-time bit error rate (BER)
measurement. We obtained a power budget of 33 dB with
0-40km of standard single mode fiber based on NRZ-OOK
modulation format for the downstream. The system stability isalso verified using deployed 40-km fiber infrastructure over 67hour real-time measurement.
REFERENCES[1] H. Zhang et al., “30km Downstream Transmission Using

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Conference 10017:
Semiconductor Lasers and Applications VII
4?25Gb/s 4-PAM Modulation with Commercial 10Gbps TOSA andROSA for 100Gb/s-PON” in Proc. OFC 2014, paper M2I.3.
[2] J. Wei et al., “First Demonstration of Real-Time End-to-End 40
Gb/s PAM-4 System using 10-G Transmitter for Next Generation
Access Applications”, Proc. ECOC, PDP.4.4, (2015).
[3] V. Houtsma et al., “Demonstration of symmetrical 25 Gbps
TDM-PON with 31.5 dB optical power budget using only 10 Gbps
optical components”, Proc. ECOC, PDP.4.3, (2015).
[4] Z. Li et al.,“28 Gb/s duobinary signal transmission over 40km
based on 10 GHz DML and PIN for 100 Gb/s PON,” Opt. Express.
Vol. 23, no.16, p.20249 (2015).
[5] Z. Ye et al., “Demonstration of high-performance costeffective 100-Gb/s TWDM-PON using 4x25-Gb/s optical
Duobinary channels with 16-GHz APD and receiver-side postequalization,” Proc. ECOC, Mo.3.4.4 (2015).

Recently, optoelectronic oscillators (OEOs) have also been
rapidly developed as emerging techniques towards sensing,measurement, and detection. A comprehensive overview to latest
advances in OEO-based sensing, measurement, and detection
applications is presented, including length change and distancemeasurement, refractive index estimation, load and strain sensing,temperature and acoustic sensing, optical clock recovery, andlow-power RF signal detection. As a new application example,
a novel approach for in-line position finding is proposed. Whena long fiber Bragg grating inserted into OEOs is locally heatedto slightly broaden its reflection spectrum, the target position
heated is mapped into the oscillating frequency shift with asensitivity of 254.66 kHz/cm in the experiment.

10017-13, Session 3[6] K. Y. Cho et al., “25.78-Gb/s operation of RSOA for nextgeneration optical access networks,” IEEE Photon. Technol. Lett.,
vol. 23, no. 8, pp. 495–497, Apr. 2011.

A novel approach for high-speed superresolution imaging (Invited Paper)

10017-11, Session 3

Hongwei Chen, Yuxi Wang, Qiang Guo, Minghua Chen,
Tsinghua Univ. (China)

SBS-assisted microwave photonic signal
processing (Invited Paper)
Wei Li, Institute of Semiconductors (China)
Stimulated Brillouin scattering (SBS) is widely used in microwave
photonic signal processing applications. Many SBS-based
microwave signal processing functions have been realizedwith extremely high performance. Microwave photonic signal
processing are generally realized by manipulating the amplitude,
phase, and state-of-polarization (SOP) of the optical signal.
The microwave signal are recovered by beating between two
optical signals in a photodetector (PD). The change of theamplitude, phase, and SOP of the optical signal will transfer tothe corresponding microwave signal. SBS effect is possible toimpart gain/loss and phase change on optical signal. Moreover,
the SBS can also pull or push the SOP of the optical signal
because the SBS provide different gain/loss on two orthogonal
polarization states. The SBS working bandwidth is related tothe bandwidth of the pump wave. Thus, the SBS bandwidth canbe varied by tailoring the pump wave. Applying both the SBS
gain and loss on the optical carrier, the amplitude of the opticalcarrier is unchanged but the phase of the optical carrier varies
with the pump power and wavelength of the optical carrier. By
beating between the optical carrier and sideband, a broadband
microwave photonic phase shifter is realized. The SBS-based slow
light is limited by the SBS interaction bandwidth. To overcome
this limitation, we used a separate carrier tuning method torealize true time delay of microwave signal with high carrier
frequency. Actually, the carrier frequency of the microwave signal
is independent on the SBS effect. Moreover, we have also applied
SBS to the microwave frequency measurement system. The SBS
enables the tuning of the measurement range and resolution,
which is realized by introducing a tunable phase to the opticalcarrier in a narrow bandwidth. In addition, the SBS can alsofind application in optical vector network analyzer (OVNA). The
accuracy of the OVNA is improved using polarization modulationand SBS-assisted polarization pulling effect. Recently, on-chip
SBS has been intensively studied. The on-chip SBS is promisingsince it is possible integrated with other optical components.

10017-12, Session 3

Sensing, measurement, and detection
enabled by optoelectronic oscillators(Invited Paper)
Xihua Zou, Southwest Jiaotong Univ. (China)

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Ever since Ernst Abbe proposed the theory of optical diffraction
limitation in 1873, efforts have never stopped to make tochallenge this iron law. Until recent, several methods find their
way to go well beyond this lateral resolution limit. Most of them
are mainly based on localization or point-scanning strategy,
which always means that they require very large number of raw
image data to reconstruct one resultant image and therefore
limits the imaging speed. However, among all these methods, atechnique known as structured illumination microscopy (SIM) is
reported to achieve a frame rate of some tens Hz, besides it has
the advantage of being label-free. Though the imaging speedof SIM can still hardly meet some extreme application such as
super-resolution video for live cells, there shows a great potential
to further improve the imaging speed of SIM.
Here we propose a new imaging strategy combing SIM with arecently developed high-speed imaging technique known as
optical pulse laser time-stretch imaging which has been provenan effective tool for high-throughput screening for living cells,
for short TS-SIM. This new method can help to improve thepattern generation rate, one of the key barrier towards higherspeed SIM, to tens of MHz, four orders of magnitudes fasterthan contemporary methods. A principle-proven experiment isconducted, and at the high pattern generation speed of 50MHz,
super resolution imaging result is acquired which surpassed thediffraction limit by a factor of 1.4.

10017-14, Session 3

All-optical modulation conversion
characteristics of an optically-injected
semiconductor laser with external
modulation of the master laser (Invited
Paper)
Yali Zhang, Jiacheng Li, Zhiyao Zhang, Shangjian Zhang,
Yong Liu, Univ. of Electronic Science and Technology ofChina (China)
The nonlinear dynamics of optically injected semiconductor
lasers have been intensively investigated. Notably, among
these various nonlinear dynamics, period-one (P1) oscillation
state is a special one due to not only its large distribution areain the space of injection parameters, but also its nearly single
sideband (SSB) of optical spectral. Therefore, it has drawn
increasing interest. Generations of millimeter waves and alloptical modulation conversion have been reported. Potentially,
this will contribute to the energy-efficient radio-over-fiber (RoF)#PhotonicsAsia

23

Conference 10017:
Semiconductor Lasers and Applications VII
systems. Alternatively, it can be used to produce pure frequency
modulation (FM) through intensity modulation (IM) suppression
and conversion, which is expected to offer many benefits suchas simple configuration, and wide frequency tunability with highmodulation frequencies.
In this paper, we focus on study of all-optical modulation
conversion characteristics, from intensity modulation (IM)to frequency modulation (FM), of an optically injected
semiconductor laser with external modulation of the master laser(ML). We present a numerical simulation on the field amplitude
time series with and without modulation data, and thus opticaland power spectra of the P1 oscillation state. The optical spectrawith data clearly show that the IM optical signal is converted into
FM one. The frequency tunability of the generated microwave
signal is shown to depend on frequency detuning between
the master and slave lasers. Based on the above quantitative
information, we numerically and experimentally carry on asystematic study on the efficiency of IM-to-FM conversion. The
numerical simulation results prove the nature of the opticallyinjected semiconductor laser as an IM limiter. We found that
IM can be effectively suppressed and actually converted to FM
by controlling injection conditions and modulation index. Thendifferent output modulation indices can be obtained. Further,
the FM is detected and demodulated through a FM discriminator.
The efficiency of IM-to-FM conversion is hence experimentally
characterized by comparing the eye diagrams before and afterconversion. Correspondingly, the experimental results show thefact of the optically injected semiconductor laser as a perfect IM
limiter.

10017-15, Session 4

Photonic microwave signal generation
using an optically-injected semiconductor
laser (Invited Paper)
Shilong Pan, Pei Zhou, Fangzheng Zhang, Nanjing Univ of
Aeronautics and Astronautics (China)
When a semiconductor laser is subject to an incoming opticalcarrier, it can exhibit rich dynamical states including stableinjection locking, periodic oscillations and chaos. Importantly,
period-one (P1) dynamics of an optically injected semiconductor
laser can be excited by undamping the relaxation resonance ofthe semiconductor lasers through Hopf bifurcation. Since themid 2000’s, the P1 dynamic state of the optically injected laser
has received increased attention for diverse applications. For
instance, by simply varying the injection strength, the detuning
frequency, or both, a continuously tunable microwave signal
over a frequency range up to 100 GHz can be generated. In thisreport, we first introduce a dual-loop optoelectronic feedback
structure to improve the spectral purity of the generated
microwave signal in the optical injection laser system, andoptical pulse compression technique is also incorporated togenerate frequency tunable short optical pulses. Since thedynamical behavior of a semiconductor has a sub-nanosecond
time scale and the P1 frequency varies with the injection
strength, it provides a convenient way to dynamically control the
instantaneous frequency of the generated microwave signal, bysimply manipulating the injection strength. Such a method canbe used to generate various waveform for different applications.
Experimental demonstrations of photonic generation of
linearly chirped microwave waveform and frequency hopping
microwave waveform are introduced. Compared with otherphotonic schemes, the proposed method features low cost,
simple structure, large time-bandwidth product (TBWP) andhigh tunability, which may find applications in radar systems,
electronic warfare and other applications.

24

SPIE Photonics Asia·

10017-16, Session 4

Self-calibrated spectrum analysis for
extracting frequency response of highspeed phase modulators (Invited Paper)
Shangjian Zhang, Yali Zhang, Heng Wang, Xinhai Zou,
Yong Liu, Univ. of Electronic Science and Technology ofChina (China)
High-speed electrooptic phase modulators are essential
elements in the high-speed optical communication system andmicrowave photonic system, due to their advantages of bias
voltage free and linear modulation. As an intrinsic parameter,
the half-wave voltage of an optical phase modulator, was often
characterized by using the electrical spectrum methods andthe optical spectrum methods in last two decades. The optical
spectrum methods are generally limited by the linewidth of thelaser source and the resolution of the available optical spectrum
analyzer (OSA), while the electrical spectrum methods require
the conversion from phase modulation to intensity modulation
before photodetection. The major difficulty of the electrical
spectrum methods lies in the extra calibration for the responsivity
fluctuation in the photodetection.
In this talk, we will demonstrate self-calibrated spectrum analysis
for characterizing high-speed phase modulators based on
the frequency-shifted heterodyne, which avoids the effect of
the responsivity fluctuation in the photodetection. Comparedto the optical spectrum method, the proposed method
achieves very high frequency resolution, and avoids the linewidth influence of laser source. Different from the traditional
electrical method, our method works without any small-signal
assumption and photodetection calibration, and eliminates thelimit of electrical driving amplitude and operating wavelength.
Moreover, it alleviates at least half bandwidth requirement
for the photodetector and spectrum analyzer. The proposed
measurement method provides very simple method for the
microwave characterization of high-speed electrooptic phasemodulators, which is also a reference for other high-speed
optoelectronic devices.

10017-17, Session 4

Stable RF signal distribution based on
passive post phase correction with only
one-stage frequency mixing
Zhiyao Jia, Ling Wang, Weiyu Wang, Chengwu Yang, Wei
Li, Ninghua Zhu, Institute of Semiconductors (China)
In this letter?we propose and demonstrate a phase stabilization
approach to distribute a radio frequency?RF?signal from remoteantenna to local station with passive post phase correction.
Simplified remote antenna structure makes it more cost-effective
for system maintenance. Without local oscillator (LO) source
involved, the system is easier to implement since there is noneed for frequency locking between the LO signal and thereceived RF signal. The key advantage of our method is that only
one-stage frequency mixing is used, which releases the systemcomplexity and reduces the conversion loss. Theoretical analysis
shows that the phase of the obtained signal at the local station
is proportional to the received RF signal, which means the phasedelay and its fluctuations induced during the fiber transmission
is corrected. A proof-of-concept experiment is performed bytransferring a RF signal through a single-mode fiber. A tunableoptical delay line (TODL) inserted between the remote antenna
and local station is used to simulate the fiber-length vibrations.
The results verifies that the phase drift of the RF signal iseffectively compressed using the proposed scheme.

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Conference 10017:
Semiconductor Lasers and Applications VII

10017-18, Session 410017-36, Session Post

Broadband x-band optically-steered PAA
with large beam-steered angle

Numerical analysis of thermal effects insemiconductor disk laser with TEC cooler

LiHong Zhang, NuanNuan Shi, Ye Deng, Shuqian Sun, Jian
Tang, Ming Li, Ninghua Zhu, Institute of Semiconductors(China)Renjiang Zhu, Peng Zhang, Maohua Jiang, Chongqing
Normal Univ. (China)

A broadband optically-steered phased array radar (PAA) is
proposed and demonstrated at X-band with a large beam swept
angle. In the proposed photonics-based PAA, eight groups ofthe true-time delay (TTD) line is designed to implement thetime delay technique of the PAA based on the optical fiber withhigh dispersion coefficient.. By using the TTD networkthe, it canresolve these problems with traditional all-electronic methods forarray control,such as bandwidth, loss, susceptibility to electromagnetic interference,beam-squintand. Although, the dispersion
value of the photonic crystal fiber (PCF) is -600 ps/nm/km,theconnect between the PCF and the SMF is adopted fiber adapter.
It increases the difficulty in the magnitude equalization andmakes the architecture instability.The dispersion coefficient of
the dispersion compensation fiber (DCF), as high as -140ps/nm/
km,is a better choice than PCF to remove the above problem.
In this paper, the DCF-based beam forming is proposed anddemonstrated based on the wavelength-swept technique. The
power deviation of ±0.5 dB and the delay error of 0.13 ps/nm
are realized by the precise calibration both the magnitude andthe phase. By tuning the optical wavelength over C band, thebeam steered angle scans from -54° to 54° with the error of 7°with the frequency from 8 GHz to 12 GHz. The beam-forming
patterns are measured and the beam deviations are within 3° inthe wavelength of 1545 nm and 1538.5 nm. It is proved that thephotonics-based technique can greatly resolve the beam squint
problem and improve the swept angle.

10017-32, Session Post

Double optical feedback self-mixing
interferometry for measurement ofYoung’s modulus
Ke Lin, Yuanlong Fan, Yanguang Yu, Jiangtao Xi, Qinghua
Guo, Jun Tong, Univ. of Wollongong (Australia)
Young’s modulus is of paramount importance for evaluating
material performance in industrial design and material
engineering. This paper presents a novel approach for
determining Young’s modulus by using double optical feedback
self-mixing interferometry (DOFSMI). The DOFSMI system
mainly consists of a laser diode (LD), a lens, a 1x2 graded-index
multimode fiber optic coupler (GIMFOC), and a specimen. Afterbeing focused by the lens, the light emitted by the LD is split into
two beams by the 1x2 GIMFOC. The two beams simultaneously
hit on the specimen and then are reflected by the specimen
which is manually excited by an impulsive excitation. The two
reflected beams re-enter into the laser cavity, thus leading to themodulation in both amplitude and frequency of the LD output
power. The modulated power can be detected by a photodiode(PD) as a DOFSMI signal which resonant frequency can be used
for determining Young’s modulus. In this paper, starting from thewell-known Lang and Kobayashi (LK) equations, we firstly derive
the theoretical model for describing the DOFSMI, based on whichan effective algorithm is developed for retrieving the resonant
frequency of the DOFSMI signal, thus for determining Young’s
modulus. The results presented in this paper show that Young’s
modulus retrieved from the DOFSMI signal is more accurate thanfrom the conventional single OFSMI.

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Thermoelectric cooler (TEC) has wide applications in thesemiconductor disk laser thermal management, and analysis of
the temperature field help to improve package performance. By
separating the responding area of Peltier effect and Joule effectin TEC, the new TEC transfer model has been established without
depending on both hot and cold side temperature to adapt to
non-uniform heat flux distribution in TEC. With finite element
method, this article has calculated the temperature distribution
characteristics, and studied the effects of TEC current, heatexchange coefficient, the heat sink and the pump laser for the
maximum temperature of quantum wells. Calculations showthat the heat transfer coefficient significantly affects the abilityof the TEC temperature shift, and cooling system performance
which is nearly inversely proportional to the heat sink thermal
conductivity is not sensitive to its the thickness variation, andthe performance of oxygen-free copper with optimization of
the area is close to diamond heatsink. Meanwhile the maximum
temperature of the quantum well has a linear relationshipwith the pump power, and increasing the pump spot size is aneffective way to increase the laser power.

10017-37, Session Post

Short-term frequency stability
measurement for narrow linewidth laser bytime domain self-heterodyne method
Lidong Lu, Nanjing Univ. (China); Xiaoyan Sun, Xiande
Bu, Binglin Li, Global Energy Interconnection ResearchInstitute (China)
For the laser short-term frequency stability measurement, it
is important to find a relatively ideal single frequency sourcewith long duration time. For this purpose, the time domain
self-heterodyne method is proposed and experimentallydemonstrated. In the method optical pulse with pulse width of
100?s is launched into a fiber with length of 125km, and then
the Rayleigh backscattering signal of the propagating pulse isused as the ideal local frequency to heterodyne with the laser
frequency generated in a short term of about 1.25ms. Then thetime domain data of the heterodyne intermediate frequency(IF) are extracted by an oscilloscopeand through short time
Fourier transform the frequency from the laser in different time
is obtained.The narrow linewidth laser is adopted as the single
frequency source for it possesses excellent monochromaticity,and the backscattering Rayleigh frequency of the light pulse
propagating in the fiber delay line helps increase the durationof the frequency source. So by time domain self-heterodyneand (short time Fourier Transform) STFT, the variation of laser
frequency in that duration time can be measured. Experimental
results show the laser linewidth has relationship with the shortterm stability of the laser, and in short-term the laser frequency
is randomly fluctuating with a range less than triple of the laser
linewidth.The measurement and evaluation of laser short-term
frequency stability benefits the application of narrow linewidthlasers in distributed optical fiber sensing area.

#PhotonicsAsia

25

Conference 10017:
Semiconductor Lasers and Applications VII

10017-38, Session Post

10017-40, Session Post

Spectrum analysis of rectangular pulse in
the atmospheric turbulence propagation

Analysis of laser energy characteristics
of laser-guided weapons based on the
hardware-in-the-loop simulation system

Yi Liu, Xiaolong Ni, Huilin Jiang, Junran Wang, Zhi Liu,
Changchun Univ. of Science and Technology (China)
Atmospheric turbulence has a great influence on the performanceof the atmospheric laser communication system reducing thesignal to noise ratio (SNR) and increasing the bit error rate (BER).
However, there is rarely study on the effect of atmosphericturbulence on the power spectrum of the rectangular pulse. In
this paper, a spectral analyzing method is used to analyze theinfluence of atmospheric turbulence on the signal. An experimentof laser beam propagation characteristic is carried out on a 6km
horizontal atmospheric link, the wavelength is 808 nm. The signal
is 100MHz rectangular pulse. The waveform of the rectangularpulse is collected by the oscilloscope, and the power spectral
density of the signal is calculated and analyzed by the method of
periodogram. Experimental results show that the response andnoise characteristics of the laser and photoelectric detector havea great influence on the signal power spectrum distribution which
can increase the noise component in the 10^6 Hz frequency
range. After the atmospheric turbulence propagation, the signal
power decreases in the whole frequency range. However, as theexistence of atmospheric turbulence, the signal power increases
in the atmospheric turbulence characteristic frequency (tens tohundreds of Hz). The noise power increases in the high frequency
range (10^7~10^8 Hz).

The hardware-in-the-loop simulation system, which provided
a precise, controllable and repeatable test conditions, was animportant part of the development of the semi-active laser (SAL)
guided systems. In this paper?laser energy chain characteristics
were studied, which provided a theoretical foundation for
the SAL guidance technology and the hardware-in-the-loop
simulation system. Firstly, according to the principles of the
hardware-in-the-loop simulation system, a parameter Z wasproposed to simplify the radar equation. Secondly, the theoreticalmodel and calculation method were given about the energy chain
characteristics based on the hardware-in-the-loop simulation
system. Then, the major factors included weather factors, thereflection characteristics of targets and the distance between the
missile and target were studied. Finally, theoretical results agree
well with the values measured experimentally?the accuracy ofmodeling was verified by experiments. And experimental results
showed that laser energy exhibited a non-linear change vs timevarying, which were in accord with the actual condition.

10017-41, Session Post

10017-39, Session Post

Design and implementation of the
hardware-in-the-loop simulation system
based on LabWindows/CVI and RTX

Molecular dynamics study on thethermal conductivity of multiple layers insemiconductor disk laser
Peng Zhang, Renjiang Zhu, Maohua Jiang, Chongqing
Normal Univ. (China); Yanrong Song, Beijing Univ. ofTechnology (China); Dingke Zhang, Yuting Cui, Chongqing
Normal Univ. (China)
Thermal properties of multiple layers including distributed Braggreflector (DBR) and multiple quantum wells (MQWs) used insemiconductor gain element are crucial for the performanceof vertical-external-cavity surface-emitting lasers (VECSELs).
For the purpose of more reasonable semiconductor wafer
designing, so to improve the thermal management of laser,
accurate thermal conductivities of DBR and MQWs are underconsiderable requirement. Whereas the diameter of pump spot ismuch larger than the total thickness of DBR and MQWs, and heatflow in a vertical-external-cavity surface-emitting laser is mainly
axial and quasi-one-dimension, therefore cross-plane thermal
conductivities of DBR and MQWs are focused. By the use ofnon-equilibrium molecular dynamics (NMD) method, cross-plane
thermal conductivities of DBR and MQWs were calculated, andsimulated results were compared with reported data. The crossplane thermal conductivity of AlAs/AlGaAs DBR, as an example,
was computed, influences of the Al composition, the interfacialroughness, and the total number of interfaces on the crossplane thermal conductivity were analyzed, and an optimized
DBR configuration was proposed. For the strained InGaAs/GaAs
MQWs, which not only provides gain to the laser wavelength, butalso works as the heat source in the active region, the cross-plane
thermal conductivity was modeled, the effects of the stress, thestrain compensate layer, and the depth of barrier on the crossplane thermal conductivity were discussed. Using the calculated
thermal conductivities, temperature rise of a vertical-externalcavity surface-emitting laser was simulated, and the theoreticalresults were in good agreement with experiment.

26

Yawen Zhu, Xiaohong Cui, Qianqian Wang, Qiujie Tong,
Xutai Cui, Chenyu Li, Le Zhang, Zhong Peng, Beijing
Institute of Technology (China)

SPIE Photonics Asia·

Qiujie Tong, Qianqian Wang, Beijing Institute ofTechnology (China); Xiaoyang Li, Bin Shan, China Huayin
Ordinance Test Ctr. (China); Xutai Cui, Chenyu Li, Zhong
Peng, Beijing Institute of Technology (China)
In order to satisfy the requirements of the real-time andgenerality, a semi-physical simulation system based on
RTX+LabWindows/CVI platform is proposed in this paper. Thissystem runs on the Windows platform, using Windows RTX
real-time extension subsystem to ensure real-time performanceof the system combining with the reflective memory network tocomplete some real-time tasks such as calculating the simulation
model, transmitting the simulation data, and keeping real-timecommunication. The real-time tasks of simulation system are
run under the RTSS process. At the same time, we use the
LabWindows/CVI to compile a graphical interface, and complete
some non-real-time tasks in the process of simulation such as
man-machine interaction, display and storage of the simulation
data which are run under the Win32 process. Through thedesign of RTX Shared memory and task scheduling algorithm
to complete the data interaction between the real-time tasks
process of RTSS and non-real-time tasks process of Win32. The
experimental results show that this system has the strongly realtime performance, highly stability, and highly simulation accuracy.
At the same time, it also has the good performance of humancomputer interaction.

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Conference 10017:
Semiconductor Lasers and Applications VII

10017-42, Session Post

All-optical sampling based on quantumdot semiconductor optical amplifier
Chen Wu, Yongjun Wang, Lina Wang, Beijing Univ. ofPosts and Telecommunications (China)
With the rapidly growing communication needs, the all-opticalsignal processing system has become a hot research field of
optical communication. This paper focused on the basic researchand practical application of quantum-dot (QD) semiconductor
optical amplifier (SOA) in all-optical sampling, and provided
critical technical support for all-optical signal processing of
ultrafast optical communication system.
Compared with bulk SOA, QD-SOA has various advantages
such as faster gain recovery time, low linewidth enhancement
factor, high saturated output power and low temperaturesensitivity, so that it is more suitable for high-speed all-opticalsignal processing. This paper established a multi-level dynamic
physical model of QD-SOA and studied its ultrafast dynamic
characteristics through theoretical and simulation research.
For further study, an all-optical sampling scheme based on the
nonlinear effect of QD-SOA is also proposed. Combining thesimulation model of QD-SOA, we analyzed the characteristics of
optical switch window and investigated the influences of different
control light pulse peak powers, pulse widths and other factors
on switch performance. The results show that, in order to get abetter sampling effect, a control light pulse of appropriate peak
power and narrow pulse width is needed. Through simulation,
this paper achieved sampling of analog signal to high frequency
pulse, in which a narrow Gaussian pulse sequence is as a probe
light, and a sinusoidal optical signal of different wavelengthfrom probe light is as a pump light, incident analog signal light
modulates the carrier density and gain of QD-SOA to rotate
the polarization state of sampling pulse light. The presented
optical sampling method has an important role in promoting theimprovement of all-optical signal processing technology.

10017-43, Session Post

All-optical D and T flip-flops based onpolarization switch of SOA
Lina Wang, Yongjun Wang, Chen Wu, Beijing Univ. ofPosts and Telecommunications (China)
The semiconductor optical amplifier (SOA) plays an importantrole in the development of the all-optical signal processing
because of the advantages of simple structure, easy integrationand strong non-linearity. Especially the nonlinear polarization
rotation effect of SOA is receiving considerable interest by
many researchers nowadays. The all-optical flip-flop using
the properties of SOA also obtains widespread attention byresearchers, as all-optical flip-flop is an important part in the fieldof all-optical signal processing. In this paper, a new all-opticalflip-flop structure using polarization switch (PSW) based onpolarization rotation effect of SOA is presented.
The main work of the paper is the simulation of all-optical logic
gates and optical SR latch. The logic gate setup only uses one
SOA, but it can get two different logic gates through a simulation.
The extinction ratio of the logic gate is about 30dB. The structureof optical SR latch utilizes the two coupled polarization rotation
switch of SOA. The structure of the flip-flop is based on thesetwo parts. To demonstrate the feasibility of the structure, we
analyze two types of flip-flops, including all-optical D and T flipflops, whose clock pulse repetition rate is 1GHz with the pulse
width of 0.3ns. The quality of all-optical flip-flop in this paper ismeasured by the falling and rising edge time. In the simulation,
the falling edge time is about 50ps, while the rising edge time
is higher than the falling edge time, because the gain increases

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slowly to the recovery time after the decrease of the gain of SOA.
The results are useful for the development of all-optical flip-flop
based on SOA.

10017-44, Session Post

A smokescreen model of laser attenuation
based on MATLAB
Heming Lee, Qianqian Wang, Yong Gong, Jing Zhao,
Beijing Institute of Technology (China); Bin Shan,
Xiaoyang Li, China Huayin Ordinance Test Ctr. (China);
Zhong Peng, Beijing Institute of Technology (China)
The model of laser through a smokescreen is built by Monte
Carlo modeling. In a traditional Monte Carlo modeling, the initial
direction cosine of photons is fixed and the radius of particles
is set the same. But the laser will diverge while traveling in theair, so changes to the traditional Monte Carlo modeling methodin photons initial motion is presented in this paper. The newmodel is compiled with MATLAB. It realized laser transmission
in mixed particles smokescreen for the first time, which cansimulate different size of particles uniformly mixed in thesmokescreen. It can be applied to smoke in the simulator of
attenuation characteristic simulation, and make the results close
to the real battlefield environment. Results show that the model
after changing the photons initial state of motion agree with theoriginal model, but the overall decrease about 10%, and mixed
smoke simulation results agree with the measured transmittanceunder the same experimental conditions with the error within 5%.

10017-45, Session Post

Dual-wavelength external-cavity laser
device for fluorescence suppression in
Raman spectroscopy
Zhang Xuting, Zhijian Cai, Jianhong Wu, Soochow Univ.
(China)Portable Raman spectrometers have been widely used in thedetection of drugs, pesticides, explosives, food additives andenvironmental pollutants. However, fluorescence disturbanceis a common trouble for these applications. Shifted excitation
Raman difference spectroscopy (SERDS) method can effectively
suppress the fluorescence background and can be easily applied
onto portable Raman spectrometers. The key of SERDS method
is to obtain a dual-wavelength laser source with narrow linewidth and small wavelength gap. In this paper, we designed
such a dual wavelength laser device based on the principles ofexternal cavity diode laser (ECDL). The device consists of twolaser diodes and a home-made blazed grating with two regionsof different periods. The beams of the laser diode modules were
projected onto the two grating regions and diffracted back into
the diodes, introducing strong external-cavity feedback andsuppressing invalid longitude modes. Since the grating regions
have different periods, the device can emit two wavelengths. The
wavelength gap can be controlled by changing the fabrication
parameters of the home-made grating. By switching on/off thedrive circuits of the laser diodes, we can conveniently enable ordisable each of the two wavelengths in the output laser beam.
The dual wavelength device proposed in this paper is low-costand compact. It also has good mechanical stability because of
no moving parts. These features make it an ideal laser source
for SERDS technique. The experiment results showed that thedual-wavelength device could emit two wavelengths with thegap smaller than 2 nanometers, and the laser power for eachwavelength could exceed 100mW.

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Conference 10017:
Semiconductor Lasers and Applications VII

10017-46, Session Post

available commercially. Life-time test has also been performed todetermine the reliability performance. Thus far more than 9000
life-test-hour has been accumulated, and there is no detectable
sign of the power degradation, indicating our devices are
extremely reliable.

A 60GHz RoF(radio-over-fiber)transmission system based on PM
modulator?
Xin Wang, Xi’an Institute of Optics and Precision
Mechanics (China) and Institute of Semiconductors(China); Yi Liu, Hunan Univ. (China); Wen-Ting
Wang, Jinhua Bai, Haiqing Yuan, Yu Liu, Institute of
Semiconductors (China)

10017-19, Session 5

As one of the most important applications of microwave
photonic?ROF (Radio over Fiber)system?which combines
the advantages of optical communication and wirelesscommunication?is a good candidate for broadband mobile
Communication?In this paper, we built and simulation a 60GHz
RoF(Radio-over-Fiber) transmission system based on PM
modulator. First, we introduce the PM-IM(Phase modulation tointensity modulation) modulation mechanisms by the breaking
the phase balanced approach. Using standard single-mode
fiber input to the F-P(Fabry-Perot) optical filter to achieve the
PM-IM modulation conversion by changing the wavelength ofthe laser or the frequency of the modulation factor of the F-P
optical filter to adapt to different fiber lengths and the signaltransmission rate. These two methods which changing the phaserelationship between the optical carrier and the optical side band
can realizing the ideal phase transition to obtain efficient andlow loss modulation conversion. Finally, the simulation results
show that different fiber lengths and the signal transmission
rate configuration of different wavelength of the laser or thefrequency of the modulation factor of the F-P optical filter?the
BER performance and the eye diagram of the 60GHz RoF
transmission system signals has been improved based on these
PM-IM modulation methods.

Yue-De Yang, Zhi-Xiong Xiao, Hai-Zhong Weng, Jin-Long
Xiao, Yong-Zhen Huang, Institute of Semiconductors(China)10017-47, Session Post

4W high-performance 1470-nm InGaAsAslasersBocang Qiu, Weimin Wang, Research Institute of Tsinghua
Univ. in Shenzhen (China); Wenbin Liu, Shenzhen Raybow
Optoelectronics Co., Ltd. (China); Chuzhong Zhao,
Langxing Kuang, Chunyu Miao, Raybow Optoelectronics
Co. Ltd (China); James Ho, Hai Martin Hu, ResearchInstitute of Tsinghua Univ Shenzhen (China)
We report on our design and fabrication of 1470 nm highpower semiconductor lasers based on an InGaAlAs strained
quantum well structure. Quantum well parameters were carefully
optimized to achieve optimum performance. In addition, anovel far field reduction structure was incorporated into our
epi structure to obtain low beam divergence and in the meantime to be without negatively impacting the threshold current.
Device characterization was made by measuring the lightcurrent-voltage (L-I-V) characteristics under continuous wave
conditions. From the measurement, it is found our 2 mm-cavity
devices with aperture size of 96 µm reach maximum powerof around 4.2 W, and the slope efficiency is about 0.42 W/A.
The devices display excellent thermal performance, with thecharacteristic temperature parameters T0 and T1 being 70 K and
600 K,respectively. Apart from the excellent external quantum
efficiency and thermal performance, devices also show reduced
beam divergence and low threshold current compared to theconventional designs. The threshold current density is only about
240 A/cm2 for the 2 mm long cavity and is reduced to 170 A/
cm2 for the 5 mm long cavity. The beam divergence (FWHM)
in the wafer growth direction is only 30 ° which is significantly
smaller than the typical value of around 40 ° of the 1470nm lasers

28

SPIE Photonics Asia·

Mode control and direct modulation forwaveguide-coupled square microcavity
lasers (Invited Paper)

Lasing mode control and direct modulation characteristics
have been investigated for waveguide-coupled unidirectionalemission square resonator microlasers. A quasi-analytical modelis introduced to analyze the mode field distributions and quality(Q) factors for the confined modes inside the square optical
microresonators with directly coupled waveguide, where high-Q
whispering-gallery-like (WG-like) modes are induced by themode coupling between doubly-degenerate modes. AlGaInAs/
InP waveguide-coupled unidirectional-emission square resonatormicrolasers are fabricated by using standard planar technology,
and electrically-injected lasing is realized at room temperature.
The lasing modes are controlled by properly designing thelasing resonator, output waveguide and injection pattern. Dualtransverse-mode lasing with a tunable wavelength interval from0.25 to 0.39 nm is realized by using a spatially selective current
injection to modulate the refractive index, as the mode field
distributions of different transverse are spatially separated. A
corresponding tunable microwave signal from 30 GHz to 48 GHz
is obtained with a high-speed photodetector. The wavelengthinterval can be further increased to a few nanometers by
reducing the resonator size and replacing the flat sidewalls withcircular arcs. The free spectra range in square microresonatorcan also be enhanced, and a mode-hopping-free single mode
operation with a continuous tuning range of 9.2 nm is realized.
The field distributions of WG-like modes distribute uniformly
in square microresonator, which avoid the burning-induced
carrier diffusion in high-speed direct modulation. A small-signal
modulation 3dB bandwidth exceeding 18 GHz, and an open eye
diagram at 25 Gb/s are demonstrated for the high-speed directmodulated square microlaser.

10017-20, Session 5

Fabrication and performanceof In0.66Ga0.34As0.73P0.27/
In0.89Ga0.11As0.23P0.77 multiplequantum-well lasers
Jia Chen, Qi Wang, Hao Liu, Zhiming Li, Xiankun Wang,
Bingfei Liu, Beijing Univ. of Posts and Telecommunications(China)We fabricated an InP-based In0.66Ga0.34As0.73P0.27/
In0.89Ga0.11As0.23P0.77 multiple-quantum-well (MQW) laser at
1.3 ?m wavelength. The device active region consists of six 5 nm
thick In0.66Ga0.34As0.73P0.27 QWs separated by 10 nm thick
In0.89Ga0.11As0.23P0.77 barrier layers. The un-doped active
region is sandwiched between 90 nm thick lattice-matched
In0.89Ga0.11As0.23P0.77 separate confinement heterostructure
layer. The waveguide core is later covered with 1.5 ?m and1.5?1.6 ?m thick n- and p-type InP cladding layers with Si andZn dopant, with doping concentration varying from 5 ? 1018
cm-3 and 5 ? 1017 and 1 ? 1018 cm-3, respectively. The cladding

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Conference 10017:
Semiconductor Lasers and Applications VII
layers are lattice-matched to the n-doped InP substrate and themetal-oxide chemical vapor deposition (MOCVD) grown device
structure is completed by a 230 nm thick highly doped (1.5 ?
1019 cm-3) In0.53Ga0.47 as contact layer. The MQW lasers arefabricated utilizing the standard fabrication process. The 100?m ridge-width lasers are later cleaved to 500 ?m length. Under
quasi-continuous wave condition, a threshold current of 400 mA
and the single side slope efficiency of 0.18 mW/mA are achieved
for a broad area device with 100 ?m-wide strip and 500 ?m-longcavity at room-temperature.

10017-21, Session 5

High-performance 808-nm GaAsP/InGaP
quantum-well lasers
Hai M. Hu, Bocang Qiu, Weimin Wang, ResearchInstitute of Tsinghua Univ. in Shenzhen (China); Chunyu
Miao, Raybow Optoelectronics Ltd. Inc (China);
James Ho, Research Institute of Tsinghua University
Shenzhen (China); Wenbin Liu, Chengpeng Li, Raybow
Optoelectronics Ltd. Inc (China)High power semiconductor lasers emitting at the wavelengthof 808 nm have a number of important applications, including
solid pumping and material processing. In this paper, we reporton our design and fabrication of very high power semiconductor
lasers based on an aluminium (Al) free core active structure. Alfree core has an advantage of higher catastrophic optical mirror
damage (COMD) threshold, and thus offers improved device
reliability compared to the AlGaAs-based devices. Asymmetricwaveguide structure was employed in our design, which allows
one to achieve high energy conversion efficiency (ECE). In
addition, a far field reduction structure was also incorporated
into our epi structure to obtain low beam divergence without
impacting the other parameters. From extensive modeling, 2 mmlong cavity with different aperture sizes was chosen for single
emitter design, and 2 mm long cavity with fill factor of 50% wasused for bar design. 45 W of optical power?limited by thermalroll-over, is obtained when the single emitter devices were tested
under QCW conditions, and more than 10 W is acquired at theoperation current of 10 A under the CW conditions. Under QCWoperation conditions, Bar power of up to 200 W is attainable
for the operation current of 200 A. In addition to the extremely
high emission power, the lasers have excellent slope efficiency
of about 1.3 W/A and beam property which is about 25 degree
measured at the full width at the half maximum (FWHM).

10017-22, Session 6

Two-section REC-based DFB laser/laser
array for RoF applications (Invited Paper)
Xiangfei Chen, Nanjing Univ. (China)
Distributed feedback (DFB) semiconductor lasers and multiwavelength DFB laser arrays (DFB-MLAs) are key components inwavelength division multiplexing networks, photonic integrated
circuits (PICs) and analogue communication systems to serve as
optical source with excellent wave-length stability, high spectral
purity and high linearity. However, the conventional DFB lasers
and DFB-MLAs suffer from low single-longitudinal-mode (SLM)
yield, poor wave-length accuracy (especially for DFB-MLAs)
and high fabri-cation cost. In order to improve the wavelength
precision and SLM yield, ?/4 phase-shifted grating combined with
an-tireﬂection/antireﬂection (AR/AR) coatings are employed.
Nevertheless, DFB lasers with ?/4 phase-shifted grating and
AR/AR coatings also suffer from several drawbacks, including
hight fabrication cost, low output efficiency and low operation
bandwidth.

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In this paper, we present a cost-efﬁcient fabrication of twosection DFB (TS-DFB) lasers and four-channel TS-DFB laser
arrays (TS-DFB-LAs) based on the reconstruction-equivalentchirp (REC) technique. In the TS-DFB lasers, one section acts as aconventional DFB laser, and the other section works as a grating
reﬂector. Compared with one-section DFB (OS-DFB) lasers
fabricated by the REC technique, most of the characteristics of
the TS-DFB lasers are improved, such as the slope efﬁciency,
side-mode suppression ratio (SMSR), small-signal frequency
response, relative intensity noise, and spurious-free dynamic
range. A radio-over-ﬁber link utilizing the TS-DFB laser as directly
modulated light source is experimentally achieved. About 50
MSym-bol/s 64-QAM signal with 10 GHz carrier is transmitted
from the TS-DFB laser. After 40 km transmission in single-mode
ﬁber, the signal quality is kept well with the average EVM of
2.97%.

10017-23, Session 6

Selective epitaxy of InP nanocrystals on
Si nano-tips for hybrid graphene/InP/Si
photodetectors (Invited Paper)
Gang Niu, Xi’an Jiaotong Univ. (China); Giovanni Capellini,
IHP-Microelectronics (Germany) and Univ. degli Studidi Roma Tre (Italy); Fariba Hatami, Humboldt-Univ. zu
Berlin (Germany); Antonio Di Bartolomeo, Univ. degliStudi di Salerno (Italy); Tore Niermann, Technische Univ.
Berlin (Germany); Emad Hameed Hussein, HumboldtUniv. zu Berlin (Germany); Markus A. Schubert, HansMichael Krause, Peter Zaumseil, Oliver Skibitzki, IHPMicroelectronics (Germany); William T. Masselink,
Humboldt-Univ. zu Berlin (Germany); Michael Lehmann,
Technische Univ. Berlin (Germany); Ya-Hong Xie, Univ.
of California, Los Angeles (United States); Thomas
Schroeder, IHP-Microelectronics (Germany) and
Brandenburgische Technische Univ. Cottbus (Germany)
The monolithic integration of III-V semiconductors having
superior (opto-)electronic properties onto the mainstream Si
technology platform presents a long-standing vision for scientists
and engineers owing to a variety of device applications, whichis, however, hindered by the fundamental materials issues suchas lattice and thermal expansion mismatch and the formationof antiphase domains. InP could open new avenues for therealization of novel devices such as high mobility transistors in
next generation CMOS (as a substrate) or efficient lasers forlight distribution in silicon photonics circuitry. We presented
here a CMOS compatible Si nanotip method to epitaxially growhigh quality InP nanocrystals (NCs) with no threading defects,
obtaining thus substrate-like optoelectronic properties onhighly heterogeneous Si substrates. Fully relaxed, site and size
controllable InP NCs were selectively grown on Si-tip wafers
due to an In-desorption dominated growth mechanism. Defects
like micro-twins and stacking faults existing in InP NCs do notseverely degrade the optical properties. A prototype hybrid
photodetector based on graphene/InP/Si device was realized
and shows promising photodetection. The results demonstrated
in this work will open up exciting opportunities for theheteroepitaxy of highly-mismatched III-V materials and thus theintegration of various high performance (opto-)electronic hybrid
devices on Si.

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Conference 10017:
Semiconductor Lasers and Applications VII

10017-24, Session 6

Infrared pulsed fiber lasers employing
2D nanomaterials as saturable absorbers(Invited Paper)
Yong Liu, Heping Li, Jianfeng Li, Univ. of Electronic
Science and Technology of China (China)
We report infrared pulsed fiber lasers using MoS2 and topologicalinsulator (TI) as saturable absorbers. An erbium-doped fiber laser
mode-locked is presented by a MoS2-based saturable absorber.
The chemical vapor deposition method is employed to growhigh-quality multilayer MoS2. Stable mode-locked soliton pulses
are achieved with central wavelength, spectral width, pulse
duration, and repetition rate of 1568.9 nm, 2.6 nm, 1.28 ps, and8.288 MHz, respectively. We also report a high energy passively
Q-switched Ho3+-doped ZBLAN fiber laser at 2979.9 nm using
TI: Bi2Te3 as the saturable absorber. Stable Q-switched pulses
at 2979.9 nm were obtained with the repetition rate of 81.96 kHz
and pulse duration of 1.37 µs. The achieved maximum output
power and pulse energy were 327.4 mW at a slope efficiencyof 11.6 % and 3.99 µJ, respectively only limited by the available
pump power. Experimental results show that 2D nanomaterials
are promising to act as saturable absorbers for realizing passive
pulsed lasers at infrared waveband.

10017-25, Session 6

A review on the development of DMLbased underwater wireless opticalcommunication systems (Invited Paper)
Jing Xu, Aobo Lin, Xiangyu Yu, Jun Han, Zhejiang Univ.
(China)Among many vital technologies for ocean exploration, theunderwater communication technology is a key enabler. Recently,
underwater wireless optical communication (UWOC) has
gained a renewed interest from both academic and industrial
communities. UWOC features sufficient bandwidth, high security
and low time latency, and consequently offers many intriguing
opportunities for a variety of applications such as communication
with seafloor sensors during a “fly-by” mission of an underwater
vehicle, real-time video transmission, underwater sensor
networks, etc. In this contribution, we will review the recent
development of DML-based UWOC systems, especially the results
obtained by Ocean College of Zhejiang University. We haveachieved a 6-m, 1.324-Gb/s underwater transmission at a BER of
2.02?10-3, by using 128-QAM OFDM signals and a low-cost PIN
photodetector, with a record spectral efficiency higher than 7.32
bits/Hz. By using an APD and 32-QAM OFDM signals, we haveachieved a record bit rate of 4.883 Gb/s at a BER of 3.20?10-3
over a 6-m underwater channel.

10017-26, Session 610017-6, Session 7

High-performance mode-locked andQ-switched lasers based on 2D transition
metal dichalcogenides (Invited Paper)
Kan Wu, Weiwen Zou, Jianping Chen, Shanghai Jiao Tong
Univ. (China)
The discovery of graphene since 2004 has triggered greatinterest in two-dimension (2D) materials for their abundantphotonic and electronic properties. Among various
demonstrations with different 2D materials, transition metal
dichalcogenides (TMDs) have caught researches’ attention
because their optical nonlinearity are estimated to be even larger
than graphene. Meanwhile, pulsed lasers including mode-locked
and Q-switched lasers are important photonic platform for bothscientific research and industrial application. Using the TMD
materials as saturable absorbers which provide pulse shaping
mechanism in a pulsed laser, one can obtain high-precision lowtiming-jitter mode-locked pulse output as well as high-energy
tunable repetition-rate Q-switched pulse output in fiber lasers.
In this work, we will present our recent advances in TMD based
pulsed laser application. Four TMD materials MoS2, WS2, MoSe2,
WSe2, have been demonstrated to achieve pulsed lasers. The
first demonstration on WS2 based mode-locked and Q-switchedlasers has become ESI hot paper and highly cited paper (Optics
Express 23, 26723, 2015). Mode-locked based on MoS2 has also
been used to generate low-phase-noise microwave signals withwide frequency tuning range and high stability. In addition,
we will also discuss the technology to achieve optical driven
deposition with ultralow threshold of 3 dBm which is 10 dB lower
than the typical threshold of this technology.

10017-28, Session 7

Optical super-resolution data storage
inspired by nanoscopy (Invited Paper)
Yaoyu Cao, Jinan Univ. (China)

Nanophotonic metasurfaces-assisted
structured light manipulation for lasing
applications (Invited Paper)
Jian Wang, Huazhong Univ. of Science and Technology(China)Metamaterials are materials engineered to have tailoredproperties that have not yet been found in nature. Photonic
metamaterials interact with optical frequencies. The twodimensional equivalents of metamaterials, also referred to as
metafilms or metasurfaces, is a new type of optical interfaces

30with patterned nanostructures, which can provide great
flexibility in structured light manipulation. Plasmonic anddielectric metasurfaces can facilitate flexible manipulation of
structured light. In this paper, we review our recent research
progress in structured light manipulation using plasmonic anddielectric metasurfaces and its potential applications in lasing:1) metasurfaces-based broadband generation of orbital angularmomentum (OAM) carrying vector beams; 2) on-chip N-fold OAM
multicasting using V-shaped antenna array metasurfaces; 3) chipscale OAM beams generation and detection using nanophotonic
dielectric metasurface array; 4) design and fabrication ofmetasurfaces on conventional optical fiber facet for linearlypolarized mode (LP11) generation at visible light wavelength; 5)
proposal and simulation of metasurfaces-assisted OAM-carrying
Bessel laser; 6) experimental demonstration of a wavelength
tunable directly excited OAM laser operating in the C-band.

SPIE Photonics Asia·

Data storage technique is expected, ever than before, to backup continued growing demands on big data processing that
confronts great challenges in cost and energy consumption
with current hard-disk-based big data centres. Compared withdata storage techniques based on electromagnetic or electronic
manipulation, such as hard disk and solid state disk, optical data
storage exhibits exceptional advantages in energy-saving andlong-time information preservation, which affords superior nearline storage and data archiving. However, the digital versatile disc(DVD) and blu-ray DVD based optical data storage techniques
are suffering from theoretical capacity limit due to the physicalbarrier, well known as the diffraction limit of light. For that Ernst
Abbe’s law gives the smallest recording bit size on the order ofwww.spie.org/pa·

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Conference 10017:
Semiconductor Lasers and Applications VII
the wavelength, the storage capacity is limited down to tens ofGigabytes per disc.
Here we report on our recent progress on the development of
optical solutions to enable nanoscopy inspired optcial superresolution data storage. This approach can directly break thediffraction limit by employing an optical dual-beam protocol. The
super-resolution storage is achieved by producing an effective
focal spot in the nanoscale for both of recording and reading
to boost the data storage capacity per disc. For the recording,we have demonstrated the bit feature size as small as 33 nm,
which leads to an equivalent storage capacity approaching 1 PB
per disc. For the reading process, optically active quantum dotswith engineered energy levels facilitate the luminescence signal
retrieved in a super-resolved manner by reversible saturable
optical fluorescence transitions (RESOLFT) process, which allows
for resolving the bit size far less than the wavelength of the laser
beam.

10017-29, Session 7976-nm passively mode-locked ytterbiumdoped fiber laser core-pumped by 915-nm
semiconductor laser diode (Invited Paper)
Yue Zhou, Beijing Univ. of Posts and Telecommunications(China)Within the past few years, femtosecond fiber lasers emitting
around 976 nm have aroused some researchers’ interest owing totheir attractive applications as seed sources in fiber amplification
systems and high power solid state amplifiers. Potentially, fiber
lasers operating around 976 nm could be further converted to
488 nm via frequency doubling, which is highly desirable toprovide a compact replacement for bulk and inefficient argon ion
lasers in applications such as communications and underwater
exploration of marine resources.
Remarkable progress has been made in ytterbium-doped fiber
lasers (YDFL) emitting around 1 µm in the past few decades.
The pulse duration and pulse repetition rate could be decently
improved if implementing passive mode-locking method.
Previous work demonstrated a double clad YDFL emitting at
976 nm. The laser is double clad multi-mode pumped, whichsuffers from relatively low conversion efficiency. Pumping withsingle-clad single-mode fibers (SMF) could obtain a higher slope
efficiency.
In this paper, we demonstrate an all-normal dispersion (ANDi)femtosecond YDFL. The laser operates around 976 nm via singleclad single-mode core-pumped method, which could enhance theslope efficiency up to 19% compared to that of 14% via doubleclad multi-mode pumped method [4]. The pulse repetition rate
is 44.3 MHz, and pulse energy is approximately 1 nJ. Throughexternal cavity pulse compression by a pair of gratings, the pulse
duration can be compressed to 250 fs, nearly transform-limited.

10017-30, Session 7

Bandwidth enhancement and time-delay
signature suppression of chaotic signal
from an optical feedback semiconductor
laser by using cross phase modulation in ahighly nonlinear fiber loop mirror
Liang-Yan Wang, Zhu-Qiong Zhong, Zheng-Mao Wu, Dong
Lu, Southwest Univ. (China); Xi Chen, Jun Chen, Southwest
Univ (China); Guang-Qiong Xia, Southwest Univ. (China)
Optical chaos generated by semiconductor lasers attracted muchattention for its extensive applications in secure communications,

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chaotic lidar, optical time domain reflectometer and fast random
bit generator etc. Among various methods to obtain opticalchaos signals, optical feedback is widely adopted for its simple
configuration, low cost and feasible controllability. However, on
one hand, the bandwidth of chaotic signal generated by opticalfeedback semiconductor laser is usually at a level of ~10 GHz,
which is mainly restricted by the relaxation oscillation frequencyof the laser. On the other hand, the time-delay signature (TDS)
originated from the optical round-trip in an external cavity
may be identified by some time-series analysis techniques andthen deteriorates the performances of optical chaos system insome potential applications. For example, the limited chaotic
bandwidth will restrict the transmission rate of optical chaos
based secure communications, and the obvious TDS may
degrade the security of the system. Therefore, it is significant
to optimize both the bandwidth and the TDS of optical chaos
signals from an external cavity optical feedback semiconductor
laser. Recently, delayed self-interference and electrical
heterodyning have been successively proposed to enhance thebandwidth of chaotic signal and suppress the TDS. In this work,
we proposed to take advantage of cross phase modulation (XPM)
in a nonlinear optical loop mirror for enhancing the bandwidth ofchaotic signal and suppressing the TDS. The influences of input
light power, power division ratio, and highly nonlinear fiber length
on the chaotic bandwidth and TDS are numerical investigated.
Detailed mappings of chaotic bandwidth and TDS evolution
show that the bandwidth of chaotic signal can be enhanced
dramatically and the TDS can also be suppressed with suitable
operation parameters, simultaneously.

10017-31, Session 8

Narrow-linewidth hybrid integrated
external-cavity diode laser for precisionapplications
Fang Wei, Guangwei Sun, Li Zhang, Gaoting Chen,
Guofeng Xin, Dijun Chen, Haiwen Cai, Zujie Fang,
Shanghai Institute of Optics and Fine Mechanics (China)
Narrow linewidth laser sources with low frequency noise are
key tools in broad range of precision applications including
high-resolution spectroscopy, interferometric optic sensing andphase coherent laser communication. In this report, we carefully
construct a compact packaged hybrid external cavity diode laser(ECDL) to operate with high spectral purity and outstanding
stability. The cavity is comprised by the single angled facet(SAF) InP gain chip and the polarization maintaining singlemode (SM) FBG (central wavelength near 1550 nm, reflectivity of
60% and 3dB FWHM of 0.1 nm). All the parts are either solderedor adhesively bonded on top of a baseplate soldered to thethermoelectric cooler (TEC) and then integrated in a 14-pin
butterfly package (31 mm?18 mm?13 mm). The module emits at
the wavelength of 1550 nm and provides 21 GHz of continuous
tunability, it produces ≥ 30 mW of polarization maintaining
fiber-coupled output power with intrinsic Lorentz linewidth ≤ 3
kHz and RIN ≤140 dB/√Hz@100 kHz. Moreover, no degradationof the power current characteristic is observed after the random
vibration (12.8gRMS) and Sine vibration test. The laser module
we reported offers superior performance, low-cost and reliable
solutions for the above mentioned precision applications.

10017-33, Session 8

Self-referenced electrical method formeasuring frequency response of highspeed Mach-Zehnder modulators based on
two-tone modulation
Heng Wang, Shangjian Zhang, Xinhai Zou, Yali Zhang,#PhotonicsAsia

31

Conference 10017:
Semiconductor Lasers and Applications VII
Yong Liu, Univ. of Electronic Science and Technology ofChina (China)

spatial matching, achieving the convenient use of the system andautomatic imaging for object observation.

The frequency response of Mach-Zehnder modulators (MZMs),
including modulation index and half-wave voltage, is criticalto the overall performance especially in the microwave andmillimeter-wave regime, which should be critically characterized
for the purpose of system evaluation and optimization. The
conventional optical spectrum analysis method and the swept
frequency method based on vector network analyzer (VNA) are
efficient in characterizing MZMs. However, the optical spectrum
analysis method is limited by frequency resolution of thecommercial grating-based optical spectrum analyzer, which only
has a frequency resolution of about 1.25 GHz (0.01 nm at 1550
nm). The widely VNA-based swept frequency method relies onde-embedding the contribution of the PD since the measured
results are always contributed to by both the MZM under test
and the PD. The major difficulty for VNA-based swept frequency
methods when the absolute frequency response is involved isthe extra calibration required for the absolute responsivity of thePD. To solve this problem, we propose and demonstrate a selfreferenced electrical method for measuring frequency responseof MZMs based on two-tone modulation. The modulation index
and half-wave voltage can be extracted from the heterodyne
ratio of two desired components by properly adjusting bias
voltage. The method avoids any roll-off calibration for the PD
responsivity in spite of the involved photodetection. Moreover,the method reduces the half bandwidth requirement for PD
and electrical spectrum analyzer (ESA) by setting a specificfrequency relationship of two-tone microwave signals. Theoreticaldescription and experimental demonstration are presented toelaborate our method. The frequency-dependent modulation
indices and half-wave voltages are experimentally measured for
a commercial MZM, and the optical spectrum analysis method is
also demonstrated for verifying the self-referenced measurementof our method.

10017-34, Session 8

Automatic range-gated laser imaging

10017-35, Session 8

Light emitters on SOI platform for opticalinterconnects
Yong Zhang, Shanghai Jiao Tong Univ. (China); Jinsong
Xia, Huazhong Univ. of Science and Technology (China);
Ciyuan Qiu, Yikai Su, Shanghai Jiao Tong Univ. (China)
We discuss light emitters in silicon photonic interconnects inthis paper. Silicon-based optical interconnect is now considered
as a promising solution to overcome the limited bandwidth andhigh power consumption of traditional electric interconnects.
However, silicon based light source is still a major challenge
due to the indirect band gap of bulk silicon. Ge self-assembled
quantum dots (QDs) have attracted much attention to realize
silicon light emitters. The advantages of Ge QDs include: easy
fabrication, light emission between 1.3 ?m and 1.6 ?m in thetelecom band and compatibility with complementary metal-oxide
semiconductor (CMOS) processes. Firstly, a light emitter basedon Ge QDs embedded in a photonic crystal ring resonator isdesigned and fabricated. Six sharp resonant peaks are present
in a photoluminescence spectrum ranging from 1500 to 1600
nm at room temperature. Next, we observe strong resonant
luminescence from Ge QDs embedded in modified PhC L3
cavities at room temperature. Five emission peaks corresponding
to the five cavity modes of modified L3 cavity, which cover a
250-nm-wide wavelength range, are observed simultaneously
in one device. Finally, a freestanding one-dimensional PhC
nanobeam cavity embedded with Ge self-assembled QDs isfabricated. Only one photoluminescence peak is observed in the
wavelength range of 1000 ~ 1600 nm at room temperature. The
emission peak dominates the photoluminescence spectrum overan almost flat and weak background emission, indicating thatsingle-mode emission is realized. These results show a possible
direction to realize effective Si-based integrated light emitting
devices based on Ge QDs in silicon cavities.

Ruirong You, Univ. of Chinese Academy of Sciences(China) and Institute of Semiconductors (China); Xinwei
Wang, Yan Zhou, Institute of Semiconductors (China)
Range-gated laser imaging is important for the applicationsof remote surveillance, object tracking, and spatial obstacle
avoidance. For counterterrorism security, military recognition,
the user has the demand for convenient use; for Underwater
Unmanned Vehicles, drones require independent imaging. So
we present a technique to accomplish automatic imaging andsolve inconvenient use problem. Firstly, the distance informationof the observed target s obtained by the laser range finder.
Then, the field of view (FOV) for target detection, recognition
and identification (DRI) is calculated referring to closed-circuit
television DRI standards. Applying equivalent number of line
pairs instead of the target-screen ratio in traditional analog video
surveillance DRI standards, an absolute quantitative evaluationis unified and convenient for digital video surveillance systems.
And multi-resolution mountain climb servo (MCS) auto focus
method is applied to obtain high detailed high quality image,guaranteeing the auto focus speed and accuracy and improving
the real-time, accuracy and robustness. This focus accuracy is
5 times better and time consuming is half less than classicalfocus. Combined with observed target distance information and
FOV depth, we demonstrate a timing and spatial matching forrange-gated depth and FOV depth, those system parameters
including the delay of the range time?the lase pulse width andintensifier gate is settled automatically. Finally, The repeatedexperimental verification of range-gated imaging system shows
this technique can meet object’s DRI testing requirements, ensure
the auto focus speed, precision and accuracy, set timing and

32

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Conference 10018:
Advanced Laser Processing and Manufacturing
Thursday 13–13 October 2016
Part of Proceedings of SPIE Vol. 10018 Advanced Laser Processing and Manufacturing10018-1, Session 1

Femtosecond laser nanojoining: theprocess, interface, filler metal, and its
application (Invited Paper)
Lei Liu, G. Zou, L. Lin, Yingchuan Zhang, Tsinghua Univ.
(China); Y. Norman Zhou, Tsinghua Univ. (China) and Univ.
of Waterloo (Canada)
Further down the road of miniaturization to nanoscale, there isan emerging need to join nanoobjects to form nanoscale devices
and systems.[1, 2] The nanojoining methods include laser beam,electron beam, soldering, sintering, resistance welding etc.
Femtosecond laser is a promising tool for nanojoining because of
its precise controlling of heat input, outstanding focusing ability,
non-linear absorption and ultra-high peak power. Femtosecond
laser induced nanojoining is also highly related to the plasmonic
thermal effect,[3] due to the localized plasmon focusing thelaser energy to a specific area and induce local melting.[4] In
this work, femtosecond laser induced nanojoining, including theprocess,[5] interface,[6] filler metal,[7] and its applications areinvestigated and the future trend is discussed.
Acknowledgements
This work was supported by National Natural Science Foundationof China (Grant No. 51405258, 51375261).

lithium-ion batteries and gas sensors. The three-dimensional
micro-/nanostructured TiO2 grown on a titanium substrate(3D-TiO2-Ti) possesses such advantages as large specificsurface area, superior light harvesting, and excellent electron
conductivity, which can effectively improve its application
performances. This study reports a novel laser-hybrid approach
to fabricate 3D-TiO2-Ti. First, the primary microarrays were
fabricated on the surface of titanium substrate by a femtosecond
laser (3D-Ti). Next, the secondary TiO2 nanostructure was grownon 3D-Ti surface by chemical treatments to form 3D-TiO2-Ti. A
variety of 3D-TiO2-Ti has been achieved recently in our group,
such as nanopore, nanowire, and nanosheet. The as-fabricated
3D-TiO2-Ti exhibited better performances in light harvesting
and absorption ability than nanostructure TiO2 grown on flattitanium surface (nanostructure-TiO2). The photocatalytic
degradation of methyl orange revealed that the size andmorphology of the primary microarrays and the secondary
nanostructures affected the photocatalytic activity of 3D-TiO2Ti synergistically. The photocatalytic efficiency was improvedby a maximum of 50% compared to that of nanostructure-TiO2.
Additionally, the photodegradation rate remained constantover several consecutive cycles, indicating that the 3D-TiO2Ti was mechanically stable. The insights from the study on
the fabrication of our 3D-TiO2-Ti can be extended to guidethe fabrication of other functional metal oxides on metallic
substrates.

References

10018-3, Session 1[1] S Guo. “The creation of nanojunctions”, Nanoscale, 2., 2521-9.
(2010)

Fabrication of 3D-embedded hollow
structures inside polymer dielectric PMMA
with femtosecond laser (Invited Paper)[2] Y. Zhou and A. Hu, “Microjoining and Nanojoining”, The OpenSurface Science Journal, 3., 32-41 (2008)[3] L. Lin, L. Liu, P. Peng, G. Zou, W.W. Duley, Y. Zhou. “In situ
nanojoining of Y- and T- shaped silver nanowires structures using
femtosecond laser radiation”, Nanotechnology, 2016, 27(12):125201..
[4] L. Lin, G. Zou, L. Liu, W.W. Duley, Y. Zhou, “Plasmonicengineering of metal-oxide nanowire heterojunctions in
integrated nanowire rectification units”, Applied Physics Letter,
2016, 108(20): 203107.
[5] L. Liu, P. Peng, A. Hu, G. Zou, W. Duley, Y.N. Zhou. Highly
Localized Heat Generation by Femtosecond Laser Induced
Plasmon Excitation in Ag Nanowires. Applied Physics Letters.
2013, 102(7): 073107.
[6] Z. Jiao, H. Huang, L. Liu, A. Hu, W. Duley, P. He, Y. Zhou.
Nanostructure Evolution in Joining of Al and Fe Nanoparticles
with Femtosecond Laser Irradiation. Journal of Applied Physics.
2014, 115(13): 134305.
[7] L. Liu, H. Huang, A. Hu, G. Zou, L. Quintino, Y. Zhou. Nano
Brazing of Pt-Ag Nanoparticles under Femtosecond Laser
Irradiation. Nano-Micro Lett. 2013, 5(2): 88-92.

10018-2, Session 1

Photocatalytic activity of threedimensional micro-/nanostructured TiO2
fabricated by femtosecond laser-hybrid
method (Invited Paper)

Chong Zheng, Tao Chen, Beijing Univ. of Technology(China); Anming Hu, Beijing Univ. of Technology (China)
and The Univ. of Tennessee Knoxville (United States);
Shibing Liu, Beijing Univ. of Technology (China)
Recent progresses in femtosecond laser (fs) manufacturing
have already proved that fs laser is a powerful tool in three
dimensional internal structure fabrication. However, most studies
are mainly focused on realize such structures in inorganic
transparent dielectric, such as photosensitive glass and fusedsilica, etc. In this study, we present a method to create embedded
internal 3D structures in a polymer dielectric material polymethyl
methacrylate (PMMA). Both continues hollow structure suchas microfluidic channels and discrete hollow structures such as
single microcavities are successfully fabricated with the help of
femtosecond lasers. Among them, complicated 3D microchannel
with a total length longer than 10mm and diameters around
80?m to 200?m are fabricated with a low repetition rate Ti:
sapphire femtosecond laser by direct laser writing at a speed
ranging from 25?m/s to 200?m/s; microcavities which function
as concave microball lenses (CMBLs) and can be applied insuper-wide-angle imaging are fabricated with a high repetition
rate femtosecond fiber laser due to the distinct accumulated
heat effect after 5s irradiation with the tightly focused laser
beam. These new approaches proved that femtosecond laser
direct writing technology has great application potential in 3D
integrated devices manufacturing in the future.

Jinlong Lu, Ting Huang, Rongshi Xiao, Beijing Univ. ofTechnology (China)
As one of the most important semiconductor functional materials,
TiO2 is widely used in photocatalysis, dye-sensitized solar cells,

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33

Conference 10018:
Advanced Laser Processing and Manufacturing10018-4, Session 1

Acknowledgement

W/Cu joining strengthened byfemtosecond laser-induced micron-scaleinterface structure

REFERENCES

This work was supported by National Natural Science Foundationof China (Grant No. 51520105007 , 51375261), by the Specialized
Research Fund for Doctoral Program of Higher Education(No.20130002110009).

Jiang Dafa, Dingwei Gong, Jiangyou Long, Fan Peixun,
Hongjun Zhang, Minlin Zhong, Tsinghua Univ. (China)
W/Cu joining is key for the fabrication of high heat load
components for thermal-nuclear reactors, which however suffersfrom the low W/Cu bonding strength due to the immiscible
nature of W-Cu system. In this study, we proposed a method
for strengthened W/Cu joining based on femtosecond (fs) laser
induced micron-scale W/Cu interface structure. W surfaces were
irradiated by fs laser ablation to form micron-scale cube arrays,
and then joined to Cu by vacuum hot pressing at 1000 ºC, 80 MPa
for 2.5 hours. The tensile strength of the W/Cu joining sample wasinvestigated. The results show that the micron-scale cube arrays
were successfully introduced into W/Cu interface without any
cracks or voids. The interface structure helps to increase the W/
Cu bonding strength to as high as 59.6 MPa, increased by about
50% as compared to W/Cu joining with a flat interface (bonding
strength 40.1 MPa). The W/Cu bonding strength shows positive
correlation with the height of the cubes and the W/Cu interface
area, indicating the possibility to control the W/Cu bonding
strength by simply adjusting the fs laser ablation parameters
for the fabrication of cube arrays on W surface. Our research
provides a method for strengthened joining between intrinsicallyimmiscible materials, including but not limited to W and Cu.

10018-5, Session 1

Heterogeneous nanowires interconnection
using femtosecond laser radiation for
integrated nanoelectronics
Luchan Lin, Lei Liu, Guisheng Zou, Tsinghua Univ. (China);
Walter W. Duley, Univ. of Waterloo (Canada); Y. Norman
Zhou, Tsinghua Univ. (China) and Univ. of Waterloo(Canada)Surface plasmon resonance (SPR), which originates from theexcitation of coherent oscillations of electrons, has been usedin tailoring heat input in nanosystems [1]. And intense heatgeneration due to strong plasmon effects under optical excitation
can be confined at the localized area around nanowires structures[2, 3]. Therefore, nanowires structures can be manipulated bythese controllable plasmon effects. Femtosecond (fs) laser, withhigh pulse intensity, can further enhance these effects. Besides,
due to the non-thermal nature of fs laser materials interaction,
low damage on base materials can be achieved.
Ag and Ag nanowires can be joined together after femtosecond
laser radiation and branched metal nanowire structure canbe achieved. And it can also be known that silver has a bad
wettability on TiO2 surface. But under the localized plasmonic
effect generated at the metal (Ag)-oxide (TiO2) junction, surface
structure of TiO2 has been modified and silver gets a better
wetting on TiO2 as a result. Joint was formed between Ag andTiO2 without much damage found in other parts adjacent to
the junction. Besides, high field intensity generated around thenanowires can also result in non-linear photon absorption (multiphoton absorption) in the dielectrics. As can be demonstrated,
nanowire networks of TiO2 were formed with joined nanowires
structures after femtosecond laser radiation. And surface
structure of nanowires has been changed accordingly underhigh laser fluence. This femtosecond laser induced nanowires
interconnection between different materials (metal and oxide)
shows great potential in integrating functional nanowire units
which can be used in the nanowires-based electronics.

34

SPIE Photonics Asia·

[1] L. Herrmann, V. Valev, C. Tserkezis, J. Barnard, S. Kasera, O.
Scherman, J. Aizpurua, and J. Baumberg Threading plasmonic
nanoparticles strings with light. Nat. Commun. 5 4568 (2014).
[2] L. Liu, P. Peng, A. Hu, G. Zou, W. Duley, and Y. Zhou, Highly
localized heat generation by femtosecond laser induced plasmon
excitation in Ag nanowires. Appl. Phys. Lett. 102, 073107 (2013).
[3] E. Garnett, W. Cai, J. Cha, F. Mahmood, S. Conner, M.
Christoforo, Y. Cui, M. McGehee, and M. Brongersma, Self-limited
plasmonic welding of silver nanowire junctions. Nat. Mater. 11, 241249 (2012).

10018-7, Session 2

Ultrafast laser enabling versatile micronano scale material processing (Invited
Paper)
Minlin Zhong, Tsinghua Univ. (China)
Ultrafast laser, with ultra-short pulse duration and ultra-highenergy density, is an emerging powerful and advanced tool for
micro-nano scale materials processing. The unique features when
an ultrafast laser interacts with materials include: (1) beyond thediffraction limit via near-filed optics principle etc. to form submicro scale or nano-scale fabrication; (2) beyond the heat-affectzone limitation via extremely non-equilibrium energy transfer
and dissipation to form high fabrication accuracy; and (3)materials independence via nonlinear effects like multi-photon
absorption and avalanche ionization to process almost any kindof materials. In recent years, ultrafast lasers in sub-ps regime andMHz repetition rate deliver average power up to multi 100W andeven over 1KW, which enables not only versatile micro-nano scalematerial processing for fundamental research, but also capable
technologies for industrial applications.
This presentation reports our recent research by using highaverage power high repetition rate ultrafast lasers: (1) ultrafast
laser enabling brand band anti-reflection surface micro-nanostructures. On laser structured micro-nano Cu surface, we
further introduce thermal oxidation to grow an kind of macromicro/nano-nanowire structure, showing a reflectance of 0.6%
at infrared 17 ?m and below 3% over 14?18 ?m (Nano Letters,
8/2015). (2) ultrafast laser enabling flexible patterning andthinning of graphene with precise layer control. Desired numberof layer was obtained by single process from original multilayer graphene when appropriate pulse threshold energy was
adopted (Scientific Report, 6/2016). (3) ultrafast laser enablingsmart superhydrophobic surfaces. Almost any kind of metal or
alloy surfaces and many organic materials can be structured toform superhydrophobicity, colorful superhydrophobicity andsuperhydrophocity with tunable adhesion (ACS Applied Materials& Interfaces, 4/2015?J. Colloid and Interface Science, 3/2015).

10018-8, Session 2

Contrastive study on micromachining
technology of sapphire substrate by
355nm nanosecond laser and 1064nm
picosecond laser
Meng Chen, Ce Yang, Xiaowei Bian, Beijing Univ. ofTechnology (China)

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Conference 10018:
Advanced Laser Processing and Manufacturing
A 355nm Nanosecond Laser and a 1064nm Picosecond Laser
are used for processing the 0.55mm thick rough sapphire
substrate respecitively.By investigated and analyzed the effectof the two lasers on the sapphire,experimental results show that:the interactions of 355nm Nanosecond Laser with sapphire is
the photo-thermal interactions and the thermal effects limits
its capability to graphics cutting on sapphire; the interactionsof 1064nm Picosecond Laser with sapphire is the photochemical interactions and it can be cold-worked cut sapphire.
Through further experimental studies,we obtained that thepower density value of the laser cutting sapphire is 1012W/
cm2 and using 1064nm Picosecond Laser successfully sapphiregraphics cutting and the complete set of process parameters
were obtained,i.e.,repetition frequency at 1kHz; pulse width at
15ps; average power at 1W; single pulse energy at 1mJ; scanningvelocity at 0.5m/s and scanning 50 times.

10018-9, Session 2

High-resolution laser lithography based on
vortex laser and composite layer
Shichao Zhan, Yiyong Liang, Xiongfeng Li, Zhejiang Univ.
(China)Traditional laser lithography systems cannot write subwavelength patterns due to the diffraction limit. In thispaper, a novel super-resolution laser direct writing method is
proposed to break through the diffraction limit. Compared withconventional lithography systems, the photoresist layer in thismethod is overlaid by an extra photochromic layer which is a
mixture of metanil yellow and aqueous PVA solution. Then avortex beam with a hollow energy distribution is used to expose
the photochromic layer and make an annular region of thephotochromic layer opaque to the writing beam. Thus, a virtual
aperture is formed in the photochromic layer which can confine
the diameter of the writing beam and reduce the linewidth
exposed in the photoresist layer. Lithography process of thisnew method was modeled and a corresponding simulation was
made. In this simulation, the intensity ratio of the two beams,
relative absorption coefficients and other parameters werechanged to study their influence to linewidth in the photoresist.
An experimental setup was designed to validate the simulation,
where the wavelengths of the writing beam and the vortex
beam are 405 nm and 532 nm, respectively. These two beams
are strictly coaxial when they are incident to the photochromic
layer. The experimental results agree quite well with the model
simulation, showing that the linewidth could be reduced byincreasing the intensity ratio of the vortex beam to the writing
beam. They also indicate that the vortex beam could effectively
reduce the lithography linewidth to 300 nm or even smaller.

10018-10, Session 2

A blue-ray laser-diode-based dual-beaminterference lithography for fabrication ofdiffraction gratings for surface encoders
Xinghui Li, Xiangwen Zhu, Qian Zhou, Xiaohao Wang, Kai
Ni, Graduate School at Shenzhen, Tsinghua Univ. (China)
The paper presents a dual-beam interference lithography
technology for fabrication of diffraction gratings for surface
encoders by using cost-effective 405 nm blue-ray laser diodes.
In this system, a dual-beam interferometer system is employed.
A laser beam raying from a compact 405 nm blu-ray laser diodeis collimated and then divided into two beams by a beam splitter.
These two beams are changed their propagation directions andinterfere with each other. Generated interference fringes are
exposed on the photoresist coated substrate. Grating line spacing
d can be adjusted by changing the incident angle between these

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two beams. Grating width Wc that determines the measurementof the surface encoder is decided by the coherence length Lc of
the laser diode and the grating line spacing d. Calculation andsimulation were carried out to decide the grating width. Lc wasexperimentally obtained. A fabrication system was constructed
to verify the feasibility of this technology. Diffraction gratings
with a 2.5 micron line spacing and a 7 mm width was obtained.
Experimental results show that this method is feasible forfabrication of gratings for surface encoders. This fabricated area
can be stitched for a 100 mm order Wc by using a precision linear
stage to move the coated grating substrate.

10018-6, Session 3

Energy-based approach as an example
for a process signature for laser
microprocessing
Tong Zhao, Salar Mehrafsun, Frank Vollertsen, Bremer
Institut für angewandte Strahltechnik GmbH (Germany)
A given part geometry can be fabricated reproducibly with thecurrent manufacturing technology, but except for the geometricdimension at the macroscopic scale, the surface integrity is
still not systematically predictable based on the processing
conditions, and vice versa. In laser ablation process, workpiecematerial is heated by electromagnetic energy and removedby the thermodynamic effects induced by phase change suchas melting, vaporization or sublimation, while laser chemicalmachining process does not heat the material beyond the melting
point and the material is removed by (electro)chemical reaction.
According to the main idea of process signature, the generated
surface integrity is not process-dependent but simply energydependent. Taking these two kinds of laser micro machining
processes as examples, this paper explores the challenges toimplement the energy-based concepts of process signaturein laser micro processing. It is expected that laser processes
and specific materials independent mechanisms can be found,which are behind the interactions among the specific energy
sources, mediums, surface, subsurface and base material.
Moreover, as a guideline, this paper discusses also the roadmap
and technical methods which can be used to realize this idea,from the monitoring of the process loadings to the evaluation ofrepresentative material modifications, and introduces the conceptof a general laser process signature concerning the total effectsof laser processes.

10018-11, Session 3

Recent research in laser surface
processing and its applications inaerospace manufacturing (Invited Paper)
Yingchun Guan, BeiHang Univ. (China)
Laser surface processing has been considered as promisingtechnique to enhance surface performance of materials orcomponents in various applications of aerospace manufacturing.
This work presents some recent applications of laser cleaningand polishing techniques on metallic substrates in our group. We
firstly demonstrate a one-stop method in minimizing oxides layer
and removing surface contaminates of Al alloy for TIG welding.
Comparison of the performance between conversional cleaning
method and laser cleaning method were examined carefully toidentify changes in microstructure and chemical analysis of Al
alloy welds. Special attention is paid to porosity distribution in
the fusion zone after laser cleaning. It is further proposed thatlaser cleaning can refine microstructure of the interface between
filter wire and the substrate during TIG welding, which may playa significant role in affecting the weld quality. Moreover, we show

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Conference 10018:
Advanced Laser Processing and Manufacturing
both oxide removal and low surface roughness achieved at hot
rolled Ni-55.0at.%Ti shape memory alloy (SMA) surface using ananosecond pulsed Nd:YAG laser. Results show that as-received
oxides with thickness of 10 micron had been removed completely
after laser cleaning, and surface roughness of laser-cleaned
surface was achieved as less than 1?m. No obvious change occur
for phase analysis and transformation temperatures of the SMA,
indicating that the influence of laser irradiation on shape memory
effect of hot rolled Ni-55.0at.%Ti SMA was negligible. Finally, we
employ laser polishing method to reduce surface roughness oflaser deposited Ti alloys. Three dimension surface profile, residual
stress, microstructure and micro hardness of laser-polishedregions are examined carefully on both as-received surface andelectrical discharge machined surface to investigate the effect oflaser polishing on the substrate.

laser beam focal point and leads to deposition of small-sized
metal structures on the surface of dielectric substrate. These
structures which have the developed surfaces and exhibit highelectrical conductivity properties can be applied for fabricationof extra small metallic conductors on dielectric surfaces without
using photomask in contrast to photolithography.
Thus, the main aim of the current work is to obtain the smallsized copper electrodes and study their sensory properties.
In order to achieve this goal we conducted the laser-induced
synthesis of porous copper deposits using the LCLD techniqueand studied the sensory activity of these structures towards
D-glucose and hydrogen peroxide detection.

Synthesis of nanoparticles by pulsed
laser ablation in air: a versatile means forflexible synthesis and separation from
Xiamen University (Invited Paper)

The high conductive porous copper microstructures with adispersion of pore size ranging from 50 nm to 50 ?m weresynthesized using laser-induced metal deposition method.
These structures have a developed effective surface area whichis 30 times higher than that observed for a pure bulk copperwith similar geometric parameters. The electrochemical studies
revealed that an analytical response of the fabricated copper
electrode is 15 times higher than those observed for a pure bulk
copper. The sensory properties towards hydrogen peroxideand D-glucose showed that the value of Faraday current at the
fabricated copper electrode is 2-2.5 orders of magnitude higher
than for a pure bulk copper used as the etalon electrode.

Rui Zhou, Tingting Huang, Shengdong Lin, Xiamen Univ.
(China)10018-14, Session 310018-12, Session 3

To make the optical limiting effect into practical applications,such as for high-speed data-processing communication
systems and broadband optical limiting devices, plasmonic
nanocomposites are explored for their strong scattering crosssection and absorption of incident optical energy at different
resonant frequencies, aiming to lower the energy thresholdand broaden the optical limiting range. To synthesize purenanocomposites dispersed in colloids, the laser ablation isapplied as a physical and environmentally friendly approach togenerate a variety of nanoparticles at different shapes, sizes, size
distributions and concentrations in liquid-based environments bycontrolling laser parameters, including laser fluence, repetition
rate and light wavelength. In this work, the formation mechanismof nanoparticles by laser ablation and their nonlinear opticallimiting performance will be briefed. Metallic nanoparticles
and their alloys are fabricated for surface plasmon resonance(SPR) enhanced nonlinear extinction properties with large lightscattering cross sections at different sizes and concentrations
by pulsed laser ablation in liquid. Laser-synthesized colloids of
mixed nanoparticles at different sizes provide more opportunities
to generate and enhance different nonlinear optical process ina disordered nanosystem. To further improve the broadband
performance of optical limiting, hybrid systems are designedby combing different sizes and compositions’ nanoparticles
dissolved in deionized water to attenuate more incident laser
light intensity. By controlling the laser ablation of different typesof solid targets, an enhanced optical limiting hybrid system basedon the use of plasmonic nanoparticles can be flexibly designed
and fabricated over a broadband range.

10018-13, Session 3

Laser-induced deposition metal fromsolution and sensory properties of copper
microstructures obtained by this method
Ilya Tumkin, Vladimir A. Kochemirovsky, Maxim S. Panov,Sergey Ermakov, Saint Petersburg State Univ. (RussianFederation)
Laser-induced chemical liquid-phase deposition of metals (LCLD)
is one of the promising and effective methods for patterningof the microelectronic devices. This technique deals with metal
reduction which proceeds in local volume of solution within the36

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Fabrication of micro holes in single-crystal
SiC wafers using mid-UV solid-state laser
Litao Qi, Fangzhou Li, Heilongjiang Institute of Scienceand Technolology (China)
This paper provides an investigation of the ablation behavior of
single crystal SiC to improve the manufacturability and hightemperature performance of SiC using laser applications. A
266nm mid-ultraviolet pulsed laser is used to investigate themicromachining of SiC wafer. The purpose is to find suitablelaser parametric regime for the fabrication of high accuracy,high spatial resolution and thin diaphragms for MEMS hightemperature pressure sensor applications. Etch rate, ablation
mechanism and quality of micromachining micro-holes areevaluated. Micro holes exhibits ripple patterns, micro-cracks andrecast layers, most of which could be eliminated by a subsequentchemical cleaning process. The ablation process is characterized
by four types of ablation mechanism, such are photomechanicalfragmentation, thermal vaporization, explosive boiling andplasma shield, which are either singly or in combination occur
as a function of pulse energy. The etch rate is obtained with
mid-ultraviolet solid-state pulsed laser ablation experiments.
Results shows mid-ultraviolet pulsed solid-state laser ablation isa high-efficiency material removal process for micromachiningof SiC-based MEMS devices. In addition, the etch rates aresubstantially high for mid-ultraviolet pulsed laser comparesto other conventional fabrications such as reaction ion andelectrochemical etching. It has been found that excellent qualityof machined features with little collateral thermal damage is
obtained in the lower pulse energy range.

10018-15, Session 3

Fabrication of three-dimensional photonic
crystal template using micro-projection
stereo lithography
Jian-Wen Dong, Yigui Chen, En-Tao Liang, Wei-Xing
Zhang, Sun Yat-Sen Univ. (China)
Photonic crystal is a material with periodic change of dielectric
constant. There exists the photonic band gap in photonic

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Conference 10018:
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crystal, which can hold back the propagation of light in a certain
frequency range. The photonic crystal has widely studied inscience and technology such as integrated optoelectronic
devices, the control of spontaneous emissions, opticalcommunications, and sensor. Three dimensional (3D) photonic
crystal is extremely concerned as it has many predominantcharacteristics, in particular for the realization on backscatteringimmune topological propagation. Such special functionality
needs to construct a 3D chiral channel in the structure ofphotonic crystals which is not compatible to the nowadays
lithography. Because those lithography technologies likechemical self-assembly technique?holographic lithography can
only fabricate the structure of complete periodicity either in twodimensionally or three dimensionally.
A micro-projection stereo lithography method is put forwardin this paper for the advantages of high customization, simple
production process, low manufacture cost and rapid prototyping.
Micro-projection stereo lithography method can actually be
regarded as one kind of additive manufacturing. It is a highlightpoint that combines such booming additive manufacturing
technology with the fabrication of three-dimensional photonic
crystal. We utilized digital micro-mirror (DMD) device anda 405nm LED array to solidify the photosensitive resin in abottom-up and layer-by-layer fashion. There are two subsystems
in the method: one is reduction optical imaging subsystem for
improving the horizontal printing resolution and adjusting theprinting size as required, and the other is feedback subsystem on
the purpose of positioning where the image is in focus.
In the paper we firstly study the light uniformity of projection
spot in micro-projection stereo lithography system, and then we
discussed on resin about its solidification resolution in horizontal
plane as well as the relationship between polymerization depth
and light exposure dose. By using such micro-projection stereo
lithography method, a 3D photonic crystal template with chiralchannel in the center has been fabricated and the lattice constantis about 390 µm. At the same time, measuring analyses and a
Fourier diffraction pattern for characterizing the 3D photonic
crystal template are presented.

10018-16, Session 3

Optical methods for correction of surface
acoustic wave sensors topology
Sergey Y. Shevchenko, Daniil V. Safronov, Alexander
S. Kukaev, Dmitry P. Lukyanov, Saint Petersburg
Electrotechnical Univ. “LETI” (Russian Federation)
Sensors based on surface acoustic waves (SAW) are becoming
more popular nowadays due to possibility of wirelessimplementation and creation of new types of these sensors,i.e. inertial ones. Originally, a photolithography process is used
for that purposes. However, production of a photo mask, which
degrades in just a several months, is a difficult and expensive
process. In addition, sensing element properties change after the
packaging is done. Therefore, it is promising to find a method tocorrect topology of packaged sensing elements (SE) and even to
produce them without photomasks.
The problem might be solved using a high-precision laser. The
essence of proposed method is to evaporate unneeded material
from a fully metallized wafer, leaving only desired topology. Thus,
it is possible to change SE topology configuration without any
essential expenses of time and money that will allow simplifying
technological process of SAW-based sensors production.
As the substrate of SAW-based SE is usually made of opticallytransparent material, the proposed method allows bilateral
topology creation. In case of a photolithography it is not possible
to form absolutely identical topologies and place them to exactly
same positions on two sides of a wafer.

research purposes. Quality of produced topology is examined.
Spectral characteristics of these elements are carried out andcompared with theoretical predictions. The received results will
be presented in the report.

10018-17, Session 3

Switchable repetition-rate bound solitons
passively mode-locked fiber laser
Xu Qin Wang, Yong Yao, Harbin Institute of Technology
Shenzhen Graduate School (China); Yanfu Yang, Harbin
Institute of Technology Graduate School (China); Ying
Long Gu, Harbin Institute of Technology (China)
The repetition rate switchable laser has a great potential inmeasurement detection, femtosecond machining and others.
And they required a stable laser and avoid the side effects,
limited pulse repetition frequency to a few kilohertz. In this caseharmonic mode-locking and suitable repetition rate fiber laser
offers advantages. Harmonic wave definitely which the repeat
frequency is integer times of the foundation frequency. Thus,
significant lengths of gain fiber are required, resulting in longcavities and low fundamental repetition rates. We demonstrated arepetition rate switchable mode-locked fiber laser based on highnonlinear fiber and Bi2Se3 saturable absorbing unit which theoutput is ultra-short pulse laser, and the amount of the harmonicis continuous adjustable beetween 1st and 14th obtained that thepolarization controller carefully rotated. And we know the role ofhigh nonlinear fiber in the ring cavity to appear muilt-wavelength.
The central of multi-wavelength of optical spectrum is 1550 nm,
and the pulse width of fundamental pulse is 873 fs. The repetition
rate varied from 193 kHz to 2.7 MHz.

10018-18, Session 3

Research of the suppression of the phasenoise in DFB fiber laser by self-injection
locking
Jianfeng Tang, Yinfa Zhang, Zhenglong Yu, Xi’an
Communication Institute (China); Shuidong Xiong, Lina
Ma, National Univ. of Defense Technology (China)
The intrinsic phase noise of distributed feedback fiber laser(DFB-FL) greatly reduces the signal to noise ratio (SNR) of
unbalanced interferometric fiber sensor system, which has anegative influence on the demodulation of tiny signal. In orderto suppress the phase noise of DFB fiber laser, a self-injecion
locking DFB-FL based on an optical circulator was presented.
Using an unbalanced Michelson interferometer with one meter
optical path difference (OPD) unequal arms, we measured thephase noise of the unlocked DFB fiber laser and self-injection
locking DFB fiber laser with one meter, one point five meter, twometers length. Result of experiment demonstrated that the phasenoise of DFB-FL was suppressed by the self-injection locking
structure, and the effect of suppression was improved with theincrease of the locking ring length. When the length of locking
ring is two meters, the phase noise above 500Hz decreases
by 8 dB and some outstanding low frequence noise decreaseobviously demodulated by an one meter OPD unbalanced
Michelson interferometer, and the mode was not hoping in eight
hours. Contrast with the unlocked DFB-FL, the pump efficiency ofself-injection locking DFB-FL was increased by 30%. In addition,
the mode of DFB-FL was not stable with the changing of thetemperature if the length of locking ring was above 2.5m.

A number of low-frequency experimental delay lines andresonators were produced using a laser ablation technique for

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37

Conference 10019:
Optoelectronic Devices and Integration VI
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10019 Optoelectronic Devices and Integration VI

10019-1, Session 1

10019-4, Session 1

Compact silicon photonic devices andhigh-density waveguide integration(Invited Paper)

Accuracy evaluation of the surface
integration of micro-POFs using a microdispensing process

Wei Jiang, Nanjing Univ. (China)

Bechir M. Hachicha, Ludger Overmeyer, Leibniz Univ.
Hannover (Germany)

Silicon photonics can potentially transform the photonics
technology owing to its low-cost fabrication and large-scale
integration advantages. Miniaturized devices and high-density
integration are the trends for future development of silicon
photonics. This talk will review our recent work on compact
silicon photonic devices based on photonic crystals andmicro-resonators as well as emerging high-density waveguide
integration technology. Particularly, ultra-high-density waveguide
integration based on a novel waveguide superlattice concept will
be discussed. Half-wavelength pitch waveguide arrays with very
low crosstalk have been demonstrated experimentally. We willshow how physics insight can be employed to overcome somecrucial limitations of integrated photonics. Potential applicationsof our work in optical interconnects, space-division multiplexing,
mode-division multiplexing, wavelength-division multiplexing,
and optical phased arrays will be discussed.

10019-2, Session 1

The application of double-layer gold
gratings in biosensors and unidirectional
couplers (Invited Paper)
In this presentation, the progress of the applications of doublelayer gold gratings in biosensing and integrated optics isreviewed. Then we report our efforts on the fabrication of
double-layer gold gratings, their applications in surface enhanced
Raman scattering spectroscopy, refractive index sensors, labelfree biosensors, unidirectional couplers for surface plasmon
polariton, optical switchers and routers.

10019-3, Session 1

Measurement of the roughness of smoothglass surfaces using optical waveguides
Katerina Kaslova, OAO VimpelCom (Russian Federation);
Anatoly N. Osovitsky, Peoples’ Friendship Univ. of Russia(Russian Federation); Nikolai D. Espinosa Ortiz, Univ. delas Fuerzas Armadas (Ecuador); Jesus A. Vila M., Univ. delPaís Vasco (Spain)
Are presented the results of measurements of surface roughnessof fluorine-containing glasses, using a new methodology forgradient waveguide propagation of the laser radiation.
This new method also allows the measurement of the attenuationof optical radiation in the surface layer of glass
The development of multiple experimental investigations confirm
the advantages of the method - high sensitivity and simplicity indevelopment.

SPIE Photonics Asia·

We evaluated the repeat accuracy of this process in this article.
A high accuracy of geometry and position of the integratedµ-POF facilitates the handling in the next step. After the surface
integration, optical axes of sender and receiver have to bealigned with the optical axis of the surface integrated µ-POF. A
high repeatability of the process allows the use of the “fit into
place” strategy to align the optical axes of beam sender andreceiver. This choice reduces the coupling process complexity as
well as its cycle time.
In this article we present the method as well as the experimental
set-up used for the accuracy evaluation. Furthermore,
possibilities to increase the accuracy are investigated anddiscussed.

Chongjun Jin, Yang Shen, Sun Yat-Sen Univ. (China)

38

Integrated waveguides are used for communication as well
as for sensing applications. They are present in PCB’s for hightransfer rate and in civil buildings for health monitoring. However,the use of integrated waveguides in simple mechanical parts is
not yet established. We are contributing to the research in thisfield by developing an automated surface integration processof micro-polymer optical fibers (µ-POF) into metallic surfaces.
The developed method uses the micro-dispensing process. We
functionalize UV-curing adhesives as cladding for micro-opticalcores as well as for inherent bonding to the substrate surface.

10019-5, Session 1

Silicon nitride grating waveguide based
directional coupler
Jijun Feng, Univ. of Shanghai for Science and Technology(China); Ryoichi Akimoto, National Institute of Advanced
Industrial Science and Technology (Japan); Heping Zeng,
East China Normal Univ. (China)
Silicon nitride is a promising wave-guiding material for integrated
photonics applications with a wide transparency bandwidth fromvisible to mid-infrared, with the superior performance in fibercoupling and propagation losses, the fabrication process moretolerant to the structure parameters variation and compatible
with the CMOS technology. Directional coupler (DC) is very
popular for realizing beam splitter because of its structural
simplicity and no excess loss intrinsically. Here, a conventional
silicon nitride directional coupler, three-dimensional vertical
coupler, and grating waveguide assisted coupler are designed
and fabricated, and compared with each other. A grating
waveguide based coupler with a period of 300 nm and coupling
length of 26 um, can realize a wideband 3-dB splitter for the
wavelength in the range from 1540 to 1620 nm, for a transverse
electric (TE) polarized wave. With further optimization of thegrating period and duty cycle, the device performance can befurther improved with wider bandwidth.

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Conference 10019:
Optoelectronic Devices and Integration VI

10019-6, Session 2

Recent developments of fiber Bragg
gratings induced by femtosecond laser(Invited Paper)
Yiping Wang, Changrui Liao, Jun He, Qiao Wang, Ying
Wang, Congzhe Zhang, Shen Liu, Shenzhen Univ. (China)
We reported recent developments of fiber Bragg gratings (FBGs)
induced by use of a femotosecond laser in Shenzhen University.
We demonstrated a method for the preparation of negativeindex fibre Bragg gratings using 800 nm femtosecond laser
overexposure and thermal regeneration. A positive-index typeI-IR FBG was first inscribed in H2-free single-mode fibre using
a femtosecond laser directed through a phase mask, and thena highly polarization dependant phase-shifted FBG (P-PSFBG)
was fabricated from the type I-IR FBG by overexposure to
the femtosecond laser. The fabrication of fiber Bragg gratings
was here demonstrated using ultrashort pulse laser pointby-point inscription. Fiber Bragg gratings were formed into
D-shaped fibers for use as refractive index sensors. A nonlinear
relationship was observed between the Bragg wavelength andliquid refractive index. We have successfully fabricated a seriesof sampled fiber Bragg gratings with easily adjustable sampling
periods and duty cycles using an 800 nm femtosecond laser
point-by-point inscription. The thermal stability of the fabricatedfiber gratings was investigated using isochronal annealing tests,
which indicated that the fiber gratings are capable of maintaining
high reflectivity at temperatures of up to 1000°C for 8 h. We
present a type of phase-shifted fiber Bragg gratings based on an
in-grating bubble fabricated by femtosecond (fs) laser ablation
together with a fusion-splicing technique. A microchannel
vertically crossing the bubble is drilled by fs laser to allow liquid
to flow in or out. By filling different refractive index (RI) liquid
into the bubble, the phase-shift peak is found to experience a
linear red shift with the increase of RI, while little contribution
to the change of phase shift comes from the temperature andaxial strain. Therefore, such a PS-FBG could be used to develop
a promising tunable optical filter and sensor. Moreover, parallel
integrated FBGs have beeb successfully fabricated in SMFs byusing femtosecond laser point-by-point inscription. More thanone FBG can be parallel inscribed in the same region of fiber andthis new grating exhibits many unique properties, such as multiwavelength operation, ultrashort grating length and outstanding
thermal stability.

10019-7, Session 2

980nm tapered lasers with photonic
crystal structure for low vertical
divergence
Xiaolong Ma, Yun Liu, Pengchao Zhao, Wanhua Zheng,
Institute of Semiconductors (China)High power tapered lasers with nearly diffraction limited beam
quality have attracted much attention in numerous applications
such as nonlinear frequency conversion, optical pumping of solidstate and fiber lasers, medical treatment and others. But the large
vertical divergence of traditional tapered lasers is a disadvantage,
which will make it expensive and difficult for beam shaping insome applications. A novel waveguide based on photonic band
crystal (PBC) concept can expand mode size and thus narrowvertical far field divergence.
In this paper, we present tapered lasers with PBC structure
emitting at 980 nm. The epitaxial layer is grown using metalorganic chemical vapor deposition. The devices have a total
length of 2 mm with 400 um long ridge waveguide and 1600
um long tapered section. The taper angel is 4o. Under quasicontinuous wave operation an output power of 3.3 W is achieved

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Follow us on:with peak conversation efficiency of 35%. The threshold current is
240 mA and the slope efficiency is 0.78 W/A. In continuous wave
mode, the output power is 2.87 W, followed by suddenly failure
resulting from catastrophic optical mirror damage (COMD). The
vertical and lateral far field divergences are 12.3o and 2.9o withfull width at half maximum (FWHM) at 0.5A. At high injectionlevel the vertical divergence doesn’t exceed 16o FWHM. Beampropagation ratio M2 is measured based on second moment
definition. High beam quality is confirmed by M2 value of lessthan 2.

10019-8, Session 2

Tunable multi-channel dropping filters
based on double-waveguide parallelcoupled microring resonators
Chunyu Zhang, Harbin Institute of Technology (China);
Xuenan Zhang, Northeastern Univ. (China); Yong Feng
Wu, Chang Qiu Yu, Yundong Zhang, Harbin Institute ofTechnology (China)
The filtering characteristics of double-waveguide parallel-coupledmicroring resonators are theoretically investigated in this paper.
The structure is described as follows. It consists of an inputthrough waveguide, a drop waveguide, and N rings coupled toboth waveguides. Each ring increases in radius by increment ofa small radius difference between adjacent rings compared to
the radii of each ring. A heater is embedded on the cladding
to impose a continuously changeable additional phase shift
between adjacent rings using thermo-optic tuning.
We theoretically analyze the following characteristics of thestructure. Transfer matrix of the structure with arbitrary numberof rings is deduced in detail. Number of the very narrow coupledresonators induced transparency (CRIT) channels, generated
within a side-coupled integrated spaced sequence of resonators(SCISSOR) stop-band via constructive interference between
adjacent slightly frequency-detuned rings, can be any desirable
integer by fabricating corresponding number of rings in the
structure. Any one or any number of arbitrary channels canbe continuously tuned and selectively switched on/off, bymodulating the additional phase shift between corresponding
pairs of rings, minimally red shifting and widening the tuned
channel when switching off, without moving or lowering theother channels greatly. In addition, numerical simulation showsthat, under inevitable tolerances of parameters, performance ofthe structure remains basically stable. The structure is compact,
reliable, flexible and tunable, and has potential vital applications
for optical switches in dense wave division multiplexing (DWDM)
systems.

10019-9, Session 2

The realization of optical switching
generated from the combination of Ag/aSi/p-Si memristor and silicon waveguide
Dongyang Li, Univ. of Electronic Science and Technology
of China (China) and Southwest Univ. for Nationalities(China); Anran Guo, Qinjian Song, Guohui Guo, Wei Li,
Univ. of Electronic Science and Technology of China(China)Much attention has been attracted by applications of memristor
in data storage, unconventional computing, and logic circuit since2008, but very few have been focused on applications in opticalswitches and optical modulators. Here, by combining a silicon
waveguide with a memristor of Ag/a-Si/p-Si structure, a novel#PhotonicsAsia

39

Conference 10019:
Optoelectronic Devices and Integration VI
optical switch (OS) for use at 1.55 ?m has been set up. The device
consists of a bottom p-Si waveguide, an upper a-Si layer and a
top Ag electrode, i.e. a sandwich structure named as Ag/a-Si/pSi. The light signal transmitting through the silicon waveguide canbe modulated by changing optical parameters of a-Si dielectric
layer in which the formation and annihilation of Ag filament canbe adjusted by an alternately electrical field between Ag and p-Si
electrodes. The distribution of optical field intensity dependence
on the thickness and refractive index of a-Si layer as well as thegeometric size of waveguide have been studied by numericalanalysis. The optical switching behavior has been simulated andthe effect of area size of Ag layer on the light signal throughthe OS has also been studied. Finally, based on Ag/a-Si/p-Si
sandwich structure and the simulated results, we have proposeda novel variable optical attenuator (VOA) and demonstrated its
function by numerical simulation.

glove box, and all materials were just stored in ambient air. The
current density (Jsc), open circuit voltage (Voc), fill factor (FF),and PCE of the solar cells are tested and studied.

10019-10, Session 210019-12, Session 3

High efficiency single transverse mode
photonic band crystal lasers with low
vertical divergence

Investigation of advanced pre- and postequalization schemes in high-order CAP
modulation-based high-speed indoor VLC
transmission system (Invited Paper)

Shaoyu Zhao, Hongwei Qu, Aiyi Qi, Yun Liu, Xuyan Zhou,
Yuzhe Lin, Wanhua Zheng, Institute of Semiconductors(China)High efficiency 980nm longitudinal photonic band crystal (PBC)
edge emitting laser diodes are studied. The calculated results
show that eight periods of Al0.1Ga0.9As and Al0.25Ga0.75As
layer pairs can reduce the vertical divergence to 10.5° full widthat half maximum (FWHM). The broad area devices show a highinternal quantum efficiency ?i of 95% and low internal loss ?iof 1.38 cm-1. Ridge waveguide (RW) lasers with 4um and 5um
strip width are fabricated. Both of them achieve good lateralbeam quality factor M2 less than 2 at 500 mA, measured using
the second moment method as recommended in ISO 11146. The
light current voltage (LIV) characteristics of 5 um strip width
uncoated devices with different cavity length are measured,and the continuous wave (CW) threshold at room temperatureare 40 mA, 48 mA and 55 mA for 1 mm, 2 mm and 3 mm cavity
length devices, respectively. Due to the high internal quantum
efficiency and low internal loss, the per-facet power conversion
efficiency (PCE) exceeds 25% for each cavity length device. In
order to achieve high power and high efficiency at the same time,the 3 mm RW lasers are coated with 99% high reflection (HR)and 4% anti reflection (AR). The coated devices obtain 425 mW
single transverse mode output power at 500 mA CW operation
with high PCE of 46%, narrow vertical divergence 11.1° and lateraldivergence 6.8° (FWHM). The slope efficiency and threshold are
0.94 W/A and 44 mA, respectively.

10019-19, Session 2

Bing Han, Jinwei Gao, South China Normal Univ. (China)

The methylammonium lead halide (CH3NH3PbX3, X = halogen;
CH3NH3: MA) based perovskite solar cells stand out from many
new solar cells in recent years, and attract the attention of many
scientific researchers. The PCE of perovskite solar cells are very
good even compared with the traditional solar cells, but it isvery difficult to fabricate perovskite solar cells in the ambient
air condition, especially when they interact with moisture in
air. In this paper, we report fabrication of perovskite solar cells
completely in air using a two-step technique without using a·

Light emitting diodes (LEDs) based visible light communication(VLC) has been considered as a promising technology forindoor high-speed wireless access, due to its unique advantages,
such as low cost, license free and high security. To achieve
high-speed VLC transmission, carrierless amplitude and phase(CAP) modulation has been utilized for its lower complexityand high spectral efficiency. Moreover, to compensate thelinear and nonlinear distortions such as frequency attenuation,
sampling time offset, LED nonlinearity etc., series of pre- andpost-equalization schemes should be employed in high-speed
VLC systems. In this paper, we make an investigation on several
advanced pre- and post-equalization schemes for high-order CAP
modulation based VLC systems. We propose to use a weighted
pre-equalization technique to compensate the LED frequency
attenuation. In post-equalization, a hybrid post equalizer is
proposed, which consists of a linear equalizer, a Volterra series
based nonlinear equalizer, and a decision-directed least meansquare (DD-LMS) equalizer. Modified cascaded multi-modulus
algorithm (M-CMMA) is employed to update the weights of thelinear and the nonlinear equalizer, while DD-LMS can further
improve the performance after the pre-convergence. Based onhigh-order CAP modulation and these equalization schemes, wehave experimentally demonstrated a 1.35-Gb/s, a 4.5-Gb/s and a
8-Gb/s high-speed indoor VLC transmission systems. The results
show the benefit and feasibility of the proposed equalization
schemes for high-speed VLC systems.

Flexible metallic transparent conductive
networks for optoelectronic applications(Invited Paper)

Xiaohui Wang, Univ. of Science and Technology of China(China)SPIE Photonics Asia

Yiguang Wang, Nan Chi, Fudan Univ. (China)

10019-13, Session 3

Preparation and evaluation of perovskite
solar cells in the absolute atmosphericenvironment

40

The cross-section SEM image of the perovskite solar cells exhibitsa well-defined layer-by-layer structure with clear interfaces.
The thicknesses of the compact TiO2, perovskite, and the
HTM layer are 60, 310, and 220 nm, respectively. As reported
before, the thickness of the perovskite layer around 310 nm is
optimal and sufficient to serve as the light-absorbing layer. XRD
pattern shows main diffraction peaks centred at 14.2° (110) and
28.5° (220), which can be assigned to the CH3NH3PbI3 phase,suggesting a crystal structure, and the peak centred at 12.7° is
attributed to PbI2. We observed unreacted PbI2 remained, whichmeans the conversion of PbI2 to perovskite on exposure to the
MAI solution is incomplete. Our best Jsc is 19.2 mA/cm2, the best
Voc is 1.0 V, the best FF is 0.65, and the best PCE is 10.2%.

Transparent conductive electrodes are essential components inmany modern optoelectronic applications, such as, touch-screen
displays, LCDs, OLEDs, wearable electronics, and solar cells
etc. New optoelectronic devices need materials with not only
high optical transmittance and electrical conductivity, but alsomechanical stability and flexibility. Traditionally, doped metaloxides play an important role in this field. However, doped metaloxides could not meet the demand of new optoelectronic devices
due to their highly brittle and the increasing cost. Recently, we

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Conference 10019:
Optoelectronic Devices and Integration VI
propose two new strategies. In first one, we demonstrated a novel
approach, based on the “cracking phenomenon” to fabricate
metallic networks, which mainly includes four steps: synthesis
and deposition of TiO2 film (as a crack material), self-cracking,metallic film deposition, and template film lift-off. The metallic
network electrodes with micrometer pitch and sub-micrometer
metallic lines, showing good electro-optical properties (withtransmittance ranging from 82 % (with ~4.2 ?/sq sheet resistance)
to 45% (with ~0.5 ?/sq sheet resistance)) and good flexibility.1
In another case, we studied two bio-inspired networks for two
specific optoelectronic applications. The first network, intended
for solar cells, light sources, and similar devices, has a quasifractal structure and is derived directly from a chemicallyextracted leaf venation system. The second network is intended
for touch-screens and flexible displays, and is obtained bymetalizing a spider’s silk web. We demonstrate that each of these
networks attain an exceptional optoelectronic and mechanicalperformance for its intended purpose, providing a promising
direction in the development of more efficient optoelectronic
devices.2(1) Han, B.; Pei, K.; Huang, Y.; Zhang, X.; Rong, Q.; Lin, Q.; Guo, Y.;
Sun, T.; Guo, C.; Carnahan, D.; Giersig, M.; Wang, Y.; Gao, J.; Ren,Z.; Kempa, K. Adv. Mater. 2014, 26 (6), 873–877.
(2) Han, B.; Huang, Y.; Li, R.; Peng, Q.; Luo, J.; Pei, K.; Herczynski,
A.; Kempa, K.; Ren, Z.; Gao, J. Nat. Commun. 2014, 5, 5674.

10019-14, Session 3

Optical implementation of neurallearning algorithms based on cross-gain
modulation in a semiconductor opticalamplifier
Qiang Li, Zhi Wang, Yansi Le, Chonghui Sun, Xiaojia Song,
Chongqing Wu, Beijing Jiaotong Univ. (China) and Key
Lab. of Luminescence and Optical Information (China)
Neuromorphic engineering has a wide range of applications in
the fields of machine learning, pattern recognition, adaptive
control, etc. Photonics, characterized by its high speed, wide
bandwidth, lower power consumption and high parallelism, is an
ideal way to realize ultrafast spiking-based information schemes.
Synaptic plasticity is believed to be critical for learning, memoryand development in neural circuits. Experimental results haveshown that changes of synapse are highly dependent on therelative timing of pre- and postsynaptic spikes. Synaptic plasticity
in which presynaptic spikes preceding postsynaptic spikes resultsin strengthening, while the opposite timing results in weakening
is called spike-timing-dependent plasticity (STDP) learning
rule. And synaptic plasticity has the opposite effect under thesame conditions is called anti-STDP learning rule. We proposedand experimentally demonstrated an optical implementation ofneural learning algorithms, which can achieve both of STDP andanti-STDP learning rule, based on the cross-gain modulation(XGM) within a single semiconductor optical amplifier (SOA,IPSAD 1501C). The weight and height of the potentitation anddepression window can be controlled independently, throughthe adjustment of the injection current of the SOA, to mimic the
biological STDP and anti-STDP learning rule more realistically.
As the injection current increases, the width of depression andpotentitation window decreases and height increases, due to thedecrease of recovery time and increase of gain under a stronger
injection current. Based on the demonstrated optical STDP andanti-STDP circuit, ultrafast learning in optical spiking neuralnetworks can be realized.

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10019-15, Session 3

Detection of atmospheric boundary
layer height in the plum rain season overHangzhou area with three-dimensionalscanning polarized lidar
Peijun Tang, Dong Liu, Peituo Xu, Yudi Zhou, Jian Bai,
Chong Liu, Kaiwei Wang, Jing Luo, Zhongtao Cheng,
Yupeng Zhang, Yongying Yang, Yibing Shen, Zhejiang
Univ. (China)
The atmospheric boundary layer can be directly influenced by
the ground and it is closely related to human activities, so thedetection and investigation of the atmospheric boundary layer
is very important. Due to the abundant rainfall in the plum rainseason in Southern China, the atmospheric boundary layer height(ABLH) is very different from any other time of the year. Lidar isan active remote-sensing instrument, and the advantage of highspatial and temporal resolution makes it very suitable for thedetection of the atmosphere. In this paper, a three-dimensional(3D) polarized Lidar is introduced and the structure will be given
in detail. Compared to traditional one-direction ground-based
Lidar, the pointing of the 3D scanning Lidar is very flexible andcan be adjusted to any direction within the up hemisphere (360
degrees by 90 degrees) in a very short time. The ABLH in theplum rain season (from May to June 2016) over Hangzhou area
(30°16? N, 120°07? E) were observed and different derivation
methods, such as the wavelet covariance method, the gradientmethod and the profile fitting method, were carried out andcompared in detail. The results show that the wavelet covariancemethod shows better stability than the gradient method andbetter accuracy than the profile fitting method. This work brings
a more flexible and accuracy way for the ABLH detection and will
be of great importance to the atmospheric study during the plumrain season.

10019-16, Session 3

Design of real-time wireless and highprecision photoelectric autocollimator
Siyu Zhou, Jiayin Hou, Shanshan Wang, Qiudong Zhu,
Beijing Institute of Technology (China)
This paper presents the design of a real-time wireless andhigh-precision photoelectric autocollimator. Firstly, long exit
pupil distance and no vignetting optical system is proposed.
Compared with the conventional optical system of autocollimator,
it solves the problem of ray cutting because of the limitationof objective lens diameter by adding an aperture in the opticalsystem and selecting optical structure with long exit pupil
distance. Besides, it eliminates the influence of stray light in the
optical system by the use of polarization beam splitting system.
Then, the design of photoelectric detection system is discussed.
After emulational and experimental analysis, adoption of acamera with a high signal to noise ratio and high frame rate can
improve the real-time measurement precision. The detection
software uses the specific multi-frame superposition algorithm
based on high speed CMOS camera. The centroid coordinatesof multi-frame images are averaged according to the FIFO(firstin first out) rule, and meanwhile adaptive thresholds and selfadapted matching windows are used for improving the real-timemeasurement accuracy. Furthermore, the measurement result
can be transmitted wirelessly to a tablet personal computer
which is convenient for the staff to adjust the instrument during
the experiment. Finally, relevant test results of the instrument
are given. The measurement accuracy of the autocollimator canreach up to 0.1? with the measurement range of 1200? and thesingle measurement time is less than 17 ms. In comparison toconventional autocollimator, the measurement accuracy and#PhotonicsAsia

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Conference 10019:
Optoelectronic Devices and Integration VI

10019-18, Session 4

measurement range have been improved. Meanwhile, it has theadvantages of real-time and remote operation.

10019-11, Session 4

High-efficiency circular polarizer based on
all-dielectric Huygens metasurface
Huan Jiang, Yongyuan Jiang, Harbin Institute ofTechnology (China)
We demonstrate an all-dielectric circular polarizer with highefficiency and broadband response in the microwave region byleveraging the recently developed Huygens metasurface. Due tothe symmetry breaking of the structure in the light propagation,
one state of the circularly polarized light can pass through freely,
while the other state is largely blocked. Specifically, the maximum
transmission reaches 0.97 with a polarization suppression ratioof 911:1, which represents a major advance in the performancecompared with previously reported circular polarizers. The
circular polarization selectivity here originates from thesimultaneous excitation of the Mie-type electric and magnetic
dipole resonances within an all-dielectric rotationally twisted
strips array. The proposed structure possesses the merits of highefficiency and simple inclusions and paves a way to constructpolarization devices by cascading tensor Huygens surfaces with
all-dielectric materials.

10019-17, Session 4

Development of next-generation
nanolithography methods to break the
optical diffraction limit (Invited Paper)
Liang Wang, Jin Qin, Li Ding, Univ. of Science andTechnology of China (China)
Nanolithography is a key technique for nanoscale pattern
definition. In the fields of photolithography, major advancements
in resolution have historically been achieved through use of
shorter wavelengths of light due to the optical diffraction limit.
Using phase shift mask and immersion technology, it has alreadybeen demonstrated that 193 nm photolithography can produce
sub-50 nm features. Along this path, such improvements comewith an ever increasing cost for photolithographic tools. The
escalating cost for photolithography tools is driven by the needfor complex sources and optics. The cost for a single tool has
exceeded $60M, a prohibitive number for many users. As aresult, researchers are looking at low cost alternative methods forprinting sub-50 nm features. Here we present two low cost highresolution lithography methods which could become the next
generation lithography tool selection.
Recent studies have showed that extraordinary opticaltransmission and nanoscale spatial resolution could be achieved
with the use of nanoscale antenna benefiting from the enhanced
transmitted light confined in the tips. We demonstrated that laser
direct writing with nanoscale antenna could achieve sub-50nm
resolution with very low cost.
Nanoimprint lithography has made tremendous progress since
its initial development. The number of technical hurdles thatmust be cleared before it is recognized as fully competitive
with photolithography for sub-50-nm patterning is dwindling.
Patterning resolution has been demonstrated down to 20 nm,
with precision overlay/alignment requirements of multilevel
device fabrication of better than 10-nm alignment resolution.

42

SPIE Photonics Asia·

Modeling of current gain compression ofa tin-incorporated group-IV alloy-basedtransistor laser
Ravi Ranjan, Prakash Pareek, Mukul K. Das, Indian Schoolof Mines (India)
The transistor laser (TL) is a unique optoelectronic device thatcan be use simultaneously as a transistor and a laser [1]. In TL
a quantum well (QW) is incorporated in base region for lasing
action so, direct bandgap III-V material has been used in TL.
Group IV semiconductor like Si and Ge are always a good choiceof materials for devices, yet not suitable for light emitting devices
because of their indirect bandgap nature. Bandgap engineeringof Ge creates an opportunity for direct bandgap group IV
material. So, silicon-germanium-tin (SixGeySn1-x-y) alloys havebeen attracting a great deal of attention in recent years. In thisperspective, authors propose a simple theoretical model for mid
infrared TL based on Tin incorporated group IV material andcalculate its optical parameters in previous work [2].
In this work we obtain the collector currents as a function ofcollector-emitter voltage (VCE) for different injected basecurrent in common-emitter (CE) mode for Si-Si0.12Ge0.73Sn0.15/
Si0.11Ge0.73Sn0.14 n-p-n transistor laser (TL) with strain balanced
Ge0.85Sn0.15 single quantum well (QW) in the base. The
proposed TL structure and values of relevant material parameters
are taken from [2]. Laser rate equation and continuity equation
are used to calculate collector current (IC) and base current (IB)as a function of collector-emitter and base-emitter voltages. It isobserve that for base currents smaller than the threshold basecurrent (IBth=1.5 mA in given structure) the current gain (?≈131)is almost constant and it work as a normal transistor. However, as
the base current exceeds IBth, the current gain decreases due tothe stimulated recombination process in the QW. The variation of? with respect to IB is also shown to illustrate gain compression
above threshold base current.
References:[1]. M. Feng, N.Holonyak, Jr., G. Walter, and R. Chan, “Roomtemperature continous wave operation of a heterojunction
bipolar transistor laser” Appl. Phys. Lett. 87, 131103 (2005).
[2]. Ravi Ranjan and Mukul K Das “Theoretical estimation of
optical gain in Tin incorporated group IV alloy based transistor
laser” Optical and Quantum Electronics, Vol.48, Article no. 201,
March 2016

10019-20, Session 4

Gain-switched thulium-doped fiber laser
with ultra-wide tuning range
Xi Cheng, Zhihong Li, Jing Hou, Zejin Liu, National Univ. of
Defense Technology (China)
Lasers working in the nominally “eye-safe” 2 ?m region haveattracted significant attention due to their wide range ofapplications in, for example, optical communications, remotesensing, material processing, medicine, as well as nonlinear
frequency conversion. For many of these applications, a widely
tunable source working in the pulsed regime is required or
highly desired due to the flexibility it can provide in operation
wavelength and temporal characteristics. The thulium-doped
fiber laser (TDFL) is a promising candidate for achieving
wideband tunable operation at ~2 ?m thanks to the distinctively
broad emission spectrum of thulium doped in silica glass. In thiscontribution, we present a gain-switched ultra-wideband tunable
TDFL built in an all-fiber format. A fiberized grating-based
tunable filter is used to select the operation wavelength. Pulsed
operation of the TDFL in the nanosecond regime is realized

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Conference 10019:
Optoelectronic Devices and Integration VI
through gain switching the system using a 1550 nm fiber master
oscillator power amplifier (MOPA) seeded by an electricallymodulated semiconductor diode laser. This TDFL features a
remarkably wide tuning range spanning 1765 – 2055 nm (24 THz
in frequency terms). The nearly 300 nm tunability doubles therecord tuning range of existing gain-switched fiber lasers, and tothe best of our knowledge, presents the broadest tuning rangethat has been reported for a monolithic pulsed fiber laser to date.
The TDFL can operate at a repetition rate of 5 – 100 kHz witha pulse width as short as 300 ns. A modest compromise in thetuning range allows pulse width reduction to sub-100 ns.

10019-38, Session Post

Optical characteristic analysis of opticalfiber near-field and far-field
Zhenlin Zhan, Fujian Normal Univ. (China); Peihua Lin,
Fujian Normal University (China); Lianhuang Li, Fujian
Normal Univ. (China)
In this work, definitions of mode-field radius and divergencehalf-angle were analyzed according to different kinds of methods.
Then, numerical calculation of these definitions was given for theLP01 mode in symmetrical step-index optical fiber and results
proved that the matching efficiency method-based, entropybased, power in the bucket-based and 1/e2-based mode-fieldradii and divergence half-angles are suitable for illuminating thenear-field and far-field characteristic respectively compared tothe two well-known second order moment-based and differential
operator-based definitions. These conclusions may provide atheoretical groundwork for designing optical fiber devices andfurther researching the propagation characteristic of optical fiber.

10019-39, Session Post

Investigation on optical and acoustic
fields of stimulated Brillouin scattering in
As2S3 suspended-core optical fibers
Qiang Xu, Weiqing Gao, Xue LI, Chenquan Ni, Xiangcai
Chen, Li Chen, Wei Zhang, Jigang Hu Sr., Xiangdong Chen,
Zijun Yuan, Hefei Univ. of Technology (China)
The optical and acoustic fields of stimulated Brillouinscattering (SBS) in the As2S3 chalcogenide suspended-coremicrostructured optical fibers (MOFs) are investigated by
the finite-element method (FEM). The optical and acoustic
fundamental modes are analyzed at 1550 nm. The core diametersof the MOFs vary from 1 to 6 µm. For each case, the holes of the
MOFs are filled with different materials such as trichlormethane(CHCL3), alcohol and water. When the core diameter is 6 µm, themaximum peak intensity of the optical fundamental mode is in
the case with air holes, while the minimum value is in the casefilled with CHCL3. The ratio of difference is ~0.66%. The minimum
peak intensity of the acoustic fundamental mode is in the casewith air holes, while the maximum value is in the case filled withwater. The ratio of difference is ~0.13%. The same rule occurs in
the fiber cores of 4.5, 3 and 2 µm, where the decreases of ~0.97%,
1.48%, 1.94% for optical field and the increases of ~0.24%, 0.34%,
0.74% for acoustic field are obtained, respectively. When thecore diameter is 1 µm, ratios of difference for optical and acoustic
fields are much higher than those in the cases of 2-6 µm, whichare ~3.55% and 29.13%, respectively. The overlap factors between
optical and acoustic fields are calculated, which are changed
with the core diameter and the filled material. Our results will
be helpful to strengthen or suppress the SBS effect in practicalapplications.

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10019-40, Session Post

A short-range optical wirelesstransmission method based on LED
Meiyuan Miao, Anlin Chen, Mingxing Zhu, Ping Li,
Dalian Polytechnic Univ. (China); Yingming Gao, Dalian
Polytechnic Univ. (China); Nianyu Zou, Dalian Polytechnic
Univ. (China)
A short-range LED optical wireless transmission method is
proposed in this paper. Furthermore achieved one to many
images transmission through this method. The system makes
MCU to be the mater controller. C# is used to convert theoriginal data of file format to binary data matched USB. MCU
encode the binary data getting from terminals by USB andmodulate the encoded signal using PWM. Drive Circuit load
the modulated signals to LED. Also, MCU control on-off of
LED with signal. Optical signal is detected by PD, throughamplified and filtered for shaping wavefrom on receiver, MCU
demodulated and decoded the signal back to binary data. Then
send to terminals like PC and reverted back to original image.
Analysis the performance from power, power consumption oftransmitter, relationship of bit error rate and modulation mode,compare modulation OOK with PWM, influence of ambient light,
respectively. The results shows that both the images can bereceived accurately which uses this method. The transfer rate
can get to 1Mbit/s using PWM modulation mode on stabilization
system with transmitter LED source of 1w, and the ambient lighteffect little to the LED transmission method in normal lightenvironment. The method is convenient to carry LED wirelessshort range transmission for mobile transmission equipment
as a supplement of Bluetooth short-range transmission for its
electromagnetic wave interfere problem, and the analysis methodin this paper can be a reference for other similar systems.

10019-41, Session Post

High-efficient slanted grating coupler
for perfectly-vertical coupling in optical
integration
Yanan Guo, Yongqing Huang, Xiao-Min Ren, Beijing Univ.
of Posts and Telecommunications (China)
A high efficient slanted grating coupler is proposed anddemonstrated for perfectly-vertical coupling between opticalfibers and silicon-on-insulator (SOI) waveguides. In the coupler,
the gratings are periodically etched on the 8°slanted siliconlayer of the SOI wafer ,the light from the fiber normally incidents
on the coupler and then horizontally propagates to the planar
waveguide layer. The properties of the slanted grating coupler
are numerically studied with the eigenmode expansion method
and simulated by COMSOL software based on the Finite Element
Method (FEM). The calculated and simulated results indicatethat the vertical-coupling slanted grating coupler offers amuch higher coupling efficiency of 88.6% than the common
planar grating coupler (~79%) under oblique incidence of thefiber at the wavelength of 1550 nm for transverse electric (TE)polarization, as well as a broad 1 dB bandwidth of 40 nm basedon the optimized design parameters including grating period,
etch depth, filling factor, buried oxide layer (BOX) thickness of
SOI, the slanted angle of the grating layer and so on. It is notedthat the device designed here not only enables a compact highefficient optical coupling process with a rather large fabrication
tolerance, but also has great practically potentials in future
optical interconnections and large-scale nanophotonic integrated
circuits.

#PhotonicsAsia

43

Conference 10019:
Optoelectronic Devices and Integration VI

10019-42, Session Post

This paper shows that the multialkali vacuum device presents
better performance under the combined conditions. Although thepower production and conversion efficiency are not very high inthis research, the experiment demonstrates how the two formsof quantum and thermal of solar energy can be simultaneously
utilized.

Directional emission microcavity lasers
with different device structures
Chang-ling Yan, Changchun Univ. of Science andTechnology (China)
Micro-cavity lasers, such as micro-disks, in which the lights are
confined with a small mode volume and high quality factor(Q-factor), have been worldwide investigated. However several
obvious disadvantages still impede their further development,such as low optical power output and isotropic far-field profile
pattern due to their circular symmetric device structures. To
overcome the intrinsic problems, the deformed structures were
proposed, including stadium-shaped lasers, bow-tie mode lasers,
spiral-shaped lasers, and so on. For the lasing material aspect, awide material range from dye-doped polymer organic material
to quantum well and quantum dots structure semiconductormaterial has been widely used in fabrication of the micro-cavity
lasers. Among those materials, electrically pumped mid-infrared
quantum cascade lasers (QCLs) are of special interest because
they are unipolar devices and hence they are not sensitive toundesirable surface recombination. In addition, mid-infrared QCLs
have a relatively long emission wavelength, therefore reducing
scattering losses due to roughness along the etched sidewallsof the micro-cavity structures. In this paper we will present
directional emitting micro-cavity lasers with different structuresof limason, triangle and ellipse shaped cavities. The mechanism of
directional emission for these deformed micro-cavity structures
is investigated and compared. In experiment, mid-infrared InP
based InGaAs/InAlAs quantum cascade laser material with about
10?m wavelength is employed to fabricate these micro-cavity
lasers. Their lasing output characteristics such as light output
power level, threshold current density, and far-field profile pattern
are investigated and also compared.

10019-44, Session Post

Chromatic dispersion and polarizationmode dispersion insensitive opticalsignal-to-noise ratio monitoring based onelectronic variable optical attenuators andoptical bandpass filter
Junde Chang, Bo Liu, Lijia Zhang, Xiangjun Xin, Qi Zhang,
Qinghua Tian, Feng Tian, XiaoLi Yin, Yongjun Wang,
Lan Rao, Beijing Univ. of Posts and Telecommunications(China)10019-43, Session Post

In this paper, an optical signal to noise ratio(OSNR) monitoring
method is proposed based on radio-frequency(RF) power
measurement of two signals in parallel connection. The signal
is split into two parallel branches equally. One branch signal isfiltered by a optical bandpass filter to remove out-band noise andthe other transmits the electronic variable optical attenuatorswith power lock control loop to keep the output power costant.
The RF power changes at the same position of the dual branchsignal processed in different ways present falling and rising
trends respectively with the increase of OSNR. The differenceof RF power at the same position is used to monitor OSNR. The
simulation results show that the proposed technique can monitor
OSNR from 2 to 30 dB with less than 1.5dB error in a 40Gb/s nonreturn-to-zero differential quadrature phase-shift keying(NRZDQPSK) transmission system, which is insensitive to chromatic
dispersion impairment and polarization mode dispersion
impairment.

The research of multi-alkali vacuum
photodiode on heating and illuminating

10019-45, Session Post

Rongguo Fu, Nanjing Univ. of Science and Technology(China); Liu Yang, National Univ. of Defense Technology(China); Guiyuan Wang, Yifang Wei, Nanjing Univ. of
Science and Technology (China); Kun Wang, Nanjing Univ.
of Science & Technology (China); Yun-sheng Qian, Nanjing
Univ. of Science and Technology (China); Hongjin Chen,
Nanjing Univ. of Science & Technology (China); Yafeng
Qiu, Nanjing Univ. of Science and Technology (China)
A novel concept for solar cell technology, photon-enhanced
thermionic emission (PETE), was proposed for harvesting
photonic and thermionic energy simultaneously. Researches showthat the conversion efficiency of PETE is pretty high, calculated
efficiencies for idealized devices can be above 50%, which isexceed the theoretical limits of single-junction photovoltaic
cells. To explore whether the vacuum device can exhibit good
performance under the conditions that combines illumination andheating, a multialkali vacuum photodiode is used as a quantum
and thermal energy converter. The band gap of multialkali
cathode is 1.1eV and the multialkali photocathode is employedat temperature below 100?.The current-voltage characteristic
curve is measured under two different temperature conditions,so is the power-voltage curve. And the conversion efficiencyof the multialkali vacuum photodiode is also calculated on thebasis of experiment data. The experiment results show that thepower converted by a heated and illuminated condition is greaterthan that obtained under illumination at room temperature or
heating without illumination. The conversion efficiency of themultialkli vacuum photodiode is higher than that not be heated.

44

SPIE Photonics Asia·

All-optical quantization by slicing
supercontinuum in a Ge11.5As24Se64.5 ribwaveguide
Yanlei Zhang, Chongxiu Yu, Kuiru Wang, Xinzhu Sang,
Mei Chao, Beijing Univ. of Posts and Telecommunications(China)All-optical Analog-digital-conversion (ADC) are widely
investigated in photonic integrated highly nonlinear waveguidefor all-optical signal processing. All-optical quantization, as
the key part of ADC, has been researched in various fields.
However, it urgently to improve the quantization resolution
and power consumption due to the limitation of the low
waveguide nonlinearity. Chalcogenide glass (ChG) waveguideas an attractive candidate is adopted in supercontinuum (SC)generation and integrated photonic circuit because of its
excellent characteristics, such as high third-order nonlinearityand easy integration. In this paper, the geometrical parametersof Ge11.5As24Se64.5 rib waveguide are optimized, making
it achieves the low positive dispersion and high nonlinear
coefficient which equals to 137.8/W*m at 1550nm . The range of
input pulse peak power is between 0.54W and 0.9W with 100 fs
pulse width. The quantization is realized by slicing the generated
highly coherent SC with an arrayed waveguide grating (AWG)on the anti-stoke side. A 4-bit quantization resolution alongwith an effective number of bits (ENOB) of 3.985 and a signalto-noise ration of 23.99 dB are achieved by appropriate designof the AWG center wavelength.With this method, the maximum

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Conference 10019:
Optoelectronic Devices and Integration VI
difference error which is lower than 0.08 is achieved.Finally, we
propose a schema of improving quantization resolution by using
tunable optical attenuator which can adjust the output power ofthe AWG and demonstrate its feasibility by numerical simulation.

10019-46, Session Post

High-performance transparent conductive
film with an embedded Ni metal meshbased on selected metal electrodeposition
process
Yanhua Liu, Su Shen, Soochow Univ. (China) and
Collaborative Innovation Ctr. of Suzhou Nano Science andTechnology (China) and Key Lab. of Advanced Optical
Manufacturing Technologies (China); Linsen Chen, Yun
Zhou, Yan Ye, Yanyan Wang, Wan Qiao, Wenbin Huang,
Soochow Univ. (China) and Collaborative Innovation Ctr.
of Suzhou Nano Science and Technology (China)
An ultra-flexible and low-sheet resistance transparent conductive
film is developed from nickel metal-mesh (Ni metal-mesh)embedded in a polyimide (PI) by exploiting selective deposition
technique coupled with photolithography and subsequent
inverted film-processing method. The novel fabrication process
exploits a metal selective electrodeposition technique tosubstitute vacuum-based metal deposition, which is crucial
for low-cost, large-area devices fabrication. The fabricatedconductive film achieved sheet resistance values as low as 0.15 ?/sq, with corresponding optical transmittance as 80% at 550 nm.
Those data indicate that the figure of merit for the conductive
film can achieve to 1.1*10^4. Due to the embedded nature of
the film, the film shows excellent adhesion and also preserves
its structural integrity and good contact with the substrate forsevere bending showing less than 4% decrease of conductivity
even after 10^4 cycles. Finally, employing the fabricated Ni metalmesh/PI conductive film, a hybrid transparent thin-film heater
is demonstrated, which exhibited higher heating temperatures(110 oC) under the lower operating voltage (1 V), lower power
consumption (79.1 oC cm^2 W^-1), and shorter response time (T <2 s) than other exiting heaters, as well as stability after repeatedtest. With superior performance and the low-cost, large-areafabrication process, our results demonstrated the metal-mesh/
PI hybrid conductive film has broad applications in flexible andstretchable optoelectronic devices.

10019-47, Session Post

Multimode fiber-focusing lens-based
plasmonics
Chunying Guan, Harbin Engineering Univ. (China)
In recent years, the prospects for the application of the beam
tailoring have attracted widespread attention for scientificresearch and commercial development. Plasmonics has emerged
as a technology that enables the creation of a wide range ofminiaturized and nanostructured photonic devices. A planarlens based on a nanoscale slit array was recently demonstrated
experimentally. We can design different geometrical structureson the fiber ends. The surface plasmon wave is modulated by the
micro structures, and the focusing lens of the all-fiber integrated
beam can be realized. The use of metal provides the advantage
of much higher index contrast over dielectric structures, resulting
in a stronger focusing capability for lenses as well as a convenientplanar geometry.
In the present work, a compact all-fiber plasmonic focusing lensis proposed and demonstrated in a conventional multimodefiber. Here, the focusing beam generator is composed of a single

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slit and a 1D groove array on the gold film deposited end facetof an optical fiber. The arrays of nanoscale slits with varying
widths in a planar metallic film can be used to focus the light
due to the modulated phase distributions. An all-fiber focusing
beam generator provides many advantages, such as no needfor alignment systems, high flexibility, lower insert loss, and easy
portability, which is of importance to realize optical trapping,micromanipulation, beam shaping, and fiber integrated devices.

10019-48, Session Post

High-precision long-term stable fiberbased optical synchronization system
Yurong Li, Shanghai Institute of Optics and Fine
Mechanics (China); Xiaochao Wang, Youen Jiang, Zhi
Qiao, Rao Li, Wei Fan, Shanghai Institute of Optics andFine Mechanics,Chinese Academy of Science (China)
A fiber-based?high precision long-term stable timesynchronization system for multi-channel laser pulses ispresented?using fiber pulse stacker combined with highspeed optical-electrical conversion and electronics processing
technology. This scheme is used to synchronize two individual
lasers including a mode-lock laser and a time shaping pulse
laser system. The relative timing jitter between two laser pulses
achieved with this system is 3.5ps(rms) in five hours. The
synchronization system is low cost and can work at ~MHz of
repetition rate.

10019-49, Session Post

A four-port vertical-coupling opticalinterface based on two-dimensional
grating coupler
Zan Zhang, Chang’an Univ. (China); Zanyun Zhang, Beiju
Huang, Institute of Semiconductors (China); Xiaochuan
Hu, Lin Zhang, Chang’an Univ. (China); Hongda Chen,
Institute of Semiconductors (China)
In this work, a fiber-to-chip vertical-coupled optical interface
with 4 ports is proposed. Lights incidences vertically from single
mode fiber can be coupled into silicon photonic chips and split
into 4 silicon waveguides. If incident light is circular polarized,
the power of the light will be equally split into 4 wavguides
with all lights travel in 4 channel converted into TE polarization,
which is favored in silicon photonic integrated circuits. The
optical interface is based on a 2-dimensional grating coupler
with carefully designed duty cycle and period. When the fiberis placed perfectly vertical on the top of the grating region, thelight beam launched from fiber is coupled in and split into 4 parts
with opposite directions. And due to the symmetry of the grating,the split ratio will be a perfect 25:25:25:25 when the vertical fiberis placed right in the grating center. In this condition, the grating
cannot only function as a coupler but also a 6-dB splitter at the
input interface. Simulation results show that coupling efficiencyof each port can reach 11.6% so that total coupling efficiency of
the interface is 46.4%. And Lights coupled into 4 waveguides
are all converted into TE polarization through the 2-dimensional
structure.

10019-50, Session Post

RF spectral analysis for characterisation ofmode-locked regimes in fibre lasers
Sergey M. Kobtsev, Sergey V. Smirnov, Alexey V. Ivanenko,#PhotonicsAsia

45

Conference 10019:
Optoelectronic Devices and Integration VI
Novosibirsk State Univ. (Russian Federation)

10019-22, Session 5

Mode-locked fibre lasers are known for their plethora ofgeneration regimes with broadly different pulse parameters.
Three types of measurements are traditionally used for
identification of these regimes: mode-locked pulse train,
autocorrelation, and optical spectrum of the mode-locked
pulses. In this work, we present our results of RF spectral
analysis applied to mode-locked lasers and propose a method of
qualitative assessment of mode-locked operation, which allows
differentiation of individual generation regimes by a parameter
calculated from RF spectra of the fundamental and the n-th
radiation harmonics. The proposed parameter is derived bothfrom the signal-to-noise ratio and from width and amount ofadditional noise present in RF spectrum of inter-mode beats at
the fundamental pulse repetition frequency and its harmonic.

Mode evolution in polarization maintainfew-mode fiber and applications in modedivision-multiplexing systems (Invited
Paper)

The approach to assessment of mode locking quality in fibre
lasers that we propose in the present work enables differentiationof pulsed generation regimes observed in fibre lasers with theaid of RF spectral analysis technique, while avoiding other, more
complicated types of measurement.

10019-51, Session Post

Solar cells based on InP/GaP/Si structure
Orest Kvitsiani, Institute of Cybernetics (Georgia); David
Laperashvili, Georgian Technical Univ. (Georgia); Tinatin
Laperashvili, Vladimer Mikelashvili, Institute of Cybernetics(Georgia)
Solar cells based on III-V semiconductors are reviewed.
Presented work emphases on the QDs solar cells for nextgeneration photovoltaic, and questions of modeling, simulationand possibilities of manufacturing of the InP/GaP/Si solar cells
are discussed. The challenges that arise from nanostructures
technologies are, also, concerned.

10019-21, Session 5

Field trail of 1-tb/s real time singlechannel optical transmission system over
1400km fiber link from Wuhan to Shanghaiwith on-line video service (Invited Paper)
Bo Liu, Xiangjun Xin, Lijia Zhang, Beijing Univ. of Posts andTelecommunications (China)
To our best knowledge, we firstly build a 1Tb/s real time
single-channel optical transmission system with service. The
transmission link is 1400km G.652 fiber link from Wuhan to
Shanghai with dispersion management which deteriorates thenonlinear damage. We employ the Nyquist filter technology
to improve the spectral efficiency while adopt the coding
modulation FEC technology to improve the transmission
performance. We find an effective way to manage the OSNR ina real employed fiber link which carriers 100G service. The 1Tb/s
optical signal is carried on five subcarriers and modulated bypolarization multiplexed 16QAM format. After 24 hour continuous
monitor, the system has achieved no error transmission after FEC
coding. The on-line video service is successfully carried on thesystem, which also supports the online chat.

46

SPIE Photonics Asia·

Yan Li, Xinglin Zeng, Jian Wu, Beijing Univ. of Posts andTelecommunications (China)
In the single mode polarization maintaining fiber (PMF), theexistence of birefringence implies that the fiber supports two
orthogonally degenerate polarized modes that have different
effective indices and hence propagate with different groupvelocities. and the dynamic of combined polarization state canbe completely characterized in terms of the Stokes parameters orPoincaré sphere, which have proved to be a useful tool in dealing
with transformation of the polarization state. However, in a few
mode polarization maintaining fiber (FM-PMF), the neff splitting
between modes within a high-order mode group will also causes
complex power sharing between elements of each LP mode set.
Hence besides the polarization state evolution, the mode patterns
in each LP set are need to be analyzed. In 1999, M. J. Padgett
and J. Courtial developed a Poincaré sphere equivalent for lightbeams containing first-order orbital angular momentum (OAM+1/
OAM-1) in LP11 mode set. Using this equivalent called the sphereof first-order modes, the analogy between free space cylindricallens converters performing mode transformation and wave plates
performing polarization state transformation was theoreticallyinvestigated.
In this letter, the completed first-order mode (LP11 mode)
evolution in PM-FMF is analyzed and represented by analogous
Jones vector and Poincaré sphere respectively. Furthermore,with Jones matrix analysis, the modal dynamics in FM-PMFs isconveniently analyzed. The conclusions are used to propose a
PM-FMF based LP11 mode rotator and an PM-FMF based OAM
generator. Both simulation and experiments are conducted toinvestigate performance of the two devices.

10019-23, Session 5

Optical polarization detection using
integrated metal gratings
Muhammad Azhar A. Naeem, Kamran Abid, Univ. of the
Punjab (Pakistan); Faiz Rahman, Univ. of Glasgow (United
Kingdom)
A semiconductor optical polarization detector based on a newlateral p-i-n diode architecture is described. This design provides
enhanced responsivity and good blue light detection capability.
A polarizing metal grating was fabricated in the middle intrinsic
part of the diode by evaporating aluminium through a grating
structure defined in resist. Several thicknesses of aluminium films
were investigated for this purpose. Some light managed to getthrough the thin films and because of the sensitivity of the lateral
p-i-n architecture caused a reduction in polarization sensitivity.
Polarization measurements were performed using a goniometerholding a Kodak polarizing sheet. The light wavelength used inthese measurements was centred at 630 nm with visible region
as spectral width. The same light was used with three different
filters to obtain blue, green and red wavelengths of light canteredat 470 nm, 550 nm, and 630 nm respectively. The output
voltage of the device was measured for different relative angles
between the grating lines and the direction of polarization for thepolarizing sheet. The voltage that was measured was developed
across a biasing resistor such that the larger photocurrents
resulted in lower voltages being measured and vice versa. Whenthe polarization direction of the polarizing sheet and the device
grating were aligned, a larger fraction of the incident light wouldwww.spie.org/pa·

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Conference 10019:
Optoelectronic Devices and Integration VI
be expected to get through, producing more photocurrent andthus a lower output voltage.
In conclusion, we have described a grating-integrated
semiconductor polarization detector that makes use of anovel base device as the underlying light sensor. The lateral
p-i-n junction architecture endows the device with enhanced
sensitivity so that it can detect changes in linear polarizationeven when the incident light is quite week.
References:[1]. Jay N. Damask, Polarization Optics in Telecommunications,
Springer (2005).
[2]. Valery V. Tuchin, Lihong Wang and Dmitry A. Zimnyakov,
Optical Polarization in Biomedical Applications, Springer (2006).

10019-24, Session 5

Experimental measurement of effective
refractive index difference for few-mode
polarization-maintaining fibers using S2
methodWenting Guo, Yan Li, Xinglin Zeng, Beijing Univ. of Posts
and Telecommunications (China); Qi Mo, FiberHome
Telecommunication Technologies Co., Ltd. (China); Wei Li,
Jian Wu, Beijing Univ. of Posts and Telecommunications(China)Polarization maintaining fibers (PMFs) can keep linear
polarization state against external perturbations by inducing
a high effective refractive index difference (?neff) along one
polarization axis. For few mode polarization maintaining fibers(FM-PMFs), ?neff is applicable between both orthogonal linear
polarization modes (e.g. LP01x and LP01y) and orthogonal
degenerated modes (e.g. LP11a and LP11b), which can enableadvanced functionalities in multiple-input-multiple-output-freespatial division multiplexing systems and optical fiber sensing
systems. Therefore, the measurement of ?neff for polarization
modes and degenerated modes is very important for determining
the quality of a FM-PMF. However, measurement of the ?neff
for FM-PMFs can be complicated due to the requirement for
generating and demultiplexing of the higher order modes(HOMs).
Spatially and Spectrally (S2) resolved imaging method, havebecome a standard technique for mode content characterizationin fibers. In this paper, we propose to measure the ?neff of FMPMFs using S2 method for the first time. The presented method is
simply by employing a tunable laser and an IR CCD camera, canavoid any mode converter or mode multiplexer/demultiplexer,
featuring a rapid testing speed. A proof-of-concept experimentis carried out to measure FM-PMFs with a length of 1.1m and 5m.
The ?neff between the orthogonal polarization modes (i.e. LP11ax11ay, LP11bx-11by, LP21ax-21ay, and LP21bx-21by) are characterizedas 7.05?10-4, 6.91?10-4, 1.02?10-3 and 1.04?10-3 respectively. The?neff of the orthogonal degenerated modes (i.e. LP11ax-11bx,
LP11ay-11by, LP21ax-21bx and LP21ay-21by) are also characterized
to be 1.39?10-4, 1.24?10-4, 5.61?10-5 and 6.53?10-5respectively.

10019-25, Session 5

Uniform flat-top interleaver consistingof a two-stage cascaded Mach-Zehnderinterferometer
Huai Yin Su, Yundong Zhang, Yong Feng Wu, Chang
Qiu Yu, Hui Li, Ping Yuan, Harbin Institute of Technology(China)Return to Contents

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Since interleaver was applied in optical communication,
its capability of splitting a set of densely spaced channels
into several sets of channels with wide channel spacing has
attracted much attention. We theoretically study a novel allfiber asymmetric interleaver consisting of a two-stage cascaded
Mach-Zehnder interferometer (MZI). The proposed interleaver
has three single mode fiber couplers linked to two differential
delays. Based on a comprehensive analysis, we demonstrate thata uniform flat-top spectral response can be obtained throughchanging the coupling coefficient rj (j=1, 2, 3) of the couplers.
The light transmission distance is fairly short in the optical fiber
device, thus we take no account of the transmission loss anddispersion in the whole process. First, we observe the change oftransmission intensity as a result of altering coupling coefficientunder the condition of fixing two coupling coefficient r1 andr2 with the different values of r3. The transmission spectrumof the two outports are comb line shape. Then, we adjust thelength of two differential delays in order to achieve an all-fiberinterleaver with unbalanced passband. is the physical lengthof the differential delays designed to be ( is the basic value) ,corresponding phase delay. The ratio of 1dB bandwidth and 3dB
bandwidth at the outports is 71.91%. According to the research
above, a near box-shaped spectral response can be generated
when we set reasonable parameters, and the passband andstopband of optical interleaver are improved significantly. The
degree of our structure is flexible which will be useful in fabricate.
And we hope that the asymmetric interleaving features will
provide a better solution for unbalanced dense wavelength
division multiplexing networks (DWDM).

10019-26, Session 5

A distributed optical fiber sensing systemfor dynamic strain measurement based on
artificial reflection array and rapid phase
discrimination
Zhenhong Sun, Xuping Zhang, Yanting Li, Yuanyuan Shan,
Yixin Zhang, Nanjing Univ. (China)
Phase sensitive optical time domain reflectometry (?-OTDR) has
been widely used in many applications for its distributed sensing
ability on weak disturbance all along the sensing fiber. However,traditional ?-OTDR cannot make quantitative measurement on
the external disturbance due to the randomly distributed position
and reflectivity of scatters within the optical fiber. Recently,
an ultra-weak FBG (UWFBG) array enhanced ?-OTDR withactive laser frequency sweeping has been proposed to realize
quantitative measurement on fiber strain variation. Unfortunately,
the sweeping scheme consumes too much time, which would
limit its application to low frequency measurement only. In thispaper, a novel distributed optical fiber sensing (DOFS) system
based on artificial reflections array and rapid phase discrimination
has been presented for dynamic strain measurement. Twoadjacent reflectors in the fiber form a fizeau interferometer. If
the interval between the two reflectors is changed, the phaseof the interference signal will also be changed. A symmetric
3?3 coupler was introduced to discriminate the phase change
through interference intensity. A software based table look-up
scheme was proposed to calculate the phase value in real-time.
The fiber length fluctuation between the two reflectors induced
by external disturbance would then be obtained accordingly. An
experiment has been made to demonstrate the validity of the
proposed method. The fiber under test was composed by fivespools of 20 meter long single mode fiber, which were cascadedwith FC/PC connector via fiber flanges. Dynamic strain wasapplied by an ordinary baffle box on the center 10m section of
the second fiber spool. Experimental results have shown that the
proposed method has good frequency response characteristic up
to 3.2 kHz and a 50dB dynamic range of linear intensity response
was successfully achieved at 500Hz while the optical probe pulse
width and repetition rate were 100ns and 10 kHz respectively.

#PhotonicsAsia

47

Conference 10019:
Optoelectronic Devices and Integration VI
Compared with previous sweeping scheme, the proposed
method has improved the measurement speed by several ordersof magnitude, which could extend the application realm of the
DOFS systems to high frequency dynamic strain measurements.

10019-27, Session 5

Xiaoxian Song, Yating Zhang, Haiting Zhang, Yu Yu,
Mingxuan Cao, Yongli Che, JianLong Wang, Xin Ding,
Jianquan Yao, Tianjin Univ. (China)
Recently, bulk-heterojunction field effect phototransistors(BH-FEpTs) based on poly [2-methoxy-5-(2´-ethylhexyloxyp-phenylenevinylene)] (MEH-PPV) and PbS quantum dot
composites have shown low photo performance in infrared(IR) illumination, due to the inherit poor carrier mobilities ofthe blends. A good method to improve the performance isintegrating the photosensitive blends with graphene, which havehigh carrier mobility up to 200,000 cm2V-1s-1. In this papers, wefabricated two type of IR FEpTs in solution process: GBH-FEpTs
applying single layer graphene beneath the bulk layers and BHFEpTs based on MEH-PPV and PbS quantum dot composites.
The photo sensitive mechanism of GBH-FEpTs can be interpreted
as follows. Photo induced carriers generate in blends in theillumination of 808nm laser. When the gate bias is applied on thedevice, a great number of photo induced carriers are dragged
down and then transferred rapidly in the bottom graphene driven
by the electric fields. As a result, holes and electrons mobilities
in the GBH-FEpTs are promoted up to 2200 and 1890 cm2V?1s?1,
two orders magnitude higher than that in BH-FEpT. As photo
induced current is in direct proportion to carrier mobilities, higher
value up to 0.18mA is achieved in the GBH-FEpTs. The GBHFEpTs exhibit higher performances in terms of photo responsivity(R) ~ 108 A/W at a light intensity (4.9 mW/cm2), higher external
quantum efficiency (EQE) (more than 1?104 %) and higher
specific detectivity (D*) (2?1012 Jones). The cooperation ofphotosensitive organic and inorganic composites with graphene
may provide a convenient route for IR photo detectors design
with high performances.

10019-28, Session 5

A calibration method for photon counters
using a customized standard light source
Shulang Lin, Huarong Gu, Qiao Feng Tan, Tsinghua Univ.
(China)Photomultiplier tubes (PMTs) are the most common photoelectric
conversion apparatus used as photon counters. Because thedark count and other properties of PMTs are greatly influenced
by temperature, photon counters need calibration. Traditional
solutions for calibration of photon counters are either basedon the inverse square law of illumination, or using lightemitting diodes (LEDs) as standard light sources. However,rigid experimental techniques are necessary for these solutions.
And the emission spectrum of LEDs does not cover the entire
spectrum of detection. This paper presents a calibration method
for photon counters using a customized standard light source
which can provide full spectrum of weak light from the darkcount level to the saturation intensity of PMTs. The photon
counter in a light-shielding cavity is connected, via an opticalfiber, to the customized standard light source attached withan intensity monitor. The calibration process is discussed andexperimental results with chemical reference substance are alsopresented for comparison.

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Coupling between fiber-optic microring
and lithium niobate microwaveguide chip
towards photonic interlink devices.
Suxu Zhou, Yiting Wang, Yuan Wang, Zhuoqi Wu, Jianhui
Yu, Zhe Chen, Huihui Lu, Jinan Univ. (China)

Improved hybrid polymer/PbS
quantum dot infrared phototransistors
incorporating single-layer graphene4810019-29, Session 5·

Lithium niobate (LN) is a key material for electro-optic
modulators and various other linear and non-linear opticalapplications since it possesses a larger electro-optic coefficent
and nonlinear optical properties. The most popular andconventional method to fabricate optical waveguide on LN
substrate is through ion doping method such as Ti (titanium)
indiffusion or annealed proton exchange (APE). Optical
microfiber coil or loop or knot resonators have been attracted
considerable attention as building blocks for optical micro andnanodevices in recent years. The micro and nanofiber (MNF)
devices needs a relatively robust substract to support its stableperformance. Therefore, it is meaningful and promising to build
an interconnection plaform between fiber-optic micro andnanodevices (such as microfiber knot resonator (MKR)) and therobust LN waveguide chip. We propose a tunable add-drop filter
based on MKR coupling into a LN APE waveguide. The widthof the LN waveguide is of ~7?m and the adjacent of each LN
waveguide distances of 140?m. The initial input light is injected
into the input port. When the diameter of MKR (D) and thediameter of microfiber (d) are ~600?m and ~7.5?m respectively,
the coupling experimental result shows a free spectral range(FSR) of 0.9 nm and Q value of 25710 at resonant wavelength of~1594 nm with full width at half maximum (FWHM) of 0.062nm
in the transmitted spectra of through port. And the FSR is of 0.6
nm and Q value of 14312.36 at resonant wavelength of ~1540.8
nm with FWHM of 0.089nm when the diameter of MKR and themicrofiber are ~850?m and ~10?m respectively.

10019-30, Session 6

A simple and low cost method to fabricate
well-controllable and organized silicon
nanowire arrays
Salah E. El-Zohary, The Univ. of Tokushima (Japan) andTanta Univ. (Egypt); Yusuke Iguchi, Masanobu Haraguchi,
The Univ. of Tokushima (Japan)
We propose a simple and low cost method to fabricate wellcontrollable and organized silicon nanowire (SiNW) arrays
avoiding complicated and expensive lithography techniques. We
have performed a series of experiments combined deposition ofa monolayer of polystyrene nanospheres, deposition of silver film,
silver film annealing and a wet chemical etching to demonstrate
the controllability of density, length and diameter of SiNWs.
Our methods leads to a well-organized SiNW arrays which ispreferable for specific optoelectronic applications compared
SiNWs which are grown with random orientations. Our previous
published work have studied Heterojunction of poly (o-toluidine)and SiNWs. Now we are aiming to replace the random growthof SiNWs by a well organized and controllable SiNW arrays.
We believe that it will enhance the performance of our device
as a heterojunction diode and also as a hybrid solarcell. Ourcontrollable SiNW arrays are needed to enhance the performanceof other optoelectronic devices.

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Conference 10019:
Optoelectronic Devices and Integration VI

10019-31, Session 6

Characterization of organic solar cells:
challenges and applications
Haifeng Meng, Limin Xiong, Junchao Zhang, National
Institute of Metrology (China); Fengjun Ye, National
Institute of Metrology (China) and Peking Univ. (China);
Yingwei He, National Institute of Metrology (China); Bifeng
Zhang, National Institute of Metrology (China) and Peking
Univ. (China); Chuan Cai, National Institute of Metrology(China)Organic solar cells have been one of the hot spots for research.
However, accurate characterization of organic solar cells is
still a challenging task. There are lots of doubts concerned tothe accuracy and reliability for its efficiency measurement,
which is harmful to further research and application of organic
solar cells. In this paper, we plan to begin with organic solar
cells’ own properties, to measure their quantum efficiency andphoto-electric characteristic accurately. Firstly, main influencing
factors will be analyzed by start with organic photovoltaic
materials absorption and spectral response, etc. Study on thecorresponding solutions to obtain data which demonstrate thetrue state for the tested samples. Secondly, measure the quantum
efficiency for organic solar cells, choose spectral matchedreference solar cells according to the spectral resposivity oforganic solar cells, calibrate accurately to obtain its Isc-STC(short-circuit current under standard test conditions). Thirdly,
choose finely calibrated and standard spectrum matched double
light source solar simulator in A+ classification, then calculate thespectral Mismatch Factor (MMF) according to IEC 60904-7, toguarantee the value accuracy during measurement. Combining
with metrology technologies for critical parameters, this paper
will demonstrate accurate measurement method for organic solar
cells, so that provide strong support for this field’s healthy andeffective development.

10019-33, Session 6

Organic semiconductor materials anddevices for visible light communications
Shuyu Zhang, Fudan Univ. (China); Pavlos P. Manousiadis,
Univ. of St. Andrews (United Kingdom); Dobroslav Tsonev,
The Univ. of Edinburgh (United Kingdom); Yue Wang,
Thomas F. Krauss, Univ. of York (United Kingdom); Harald
Haas, The Univ. of Edinburgh (United Kingdom); Ifor D. W.
Samuel, Graham A. Turnbull, Univ. of St. Andrews (United
Kingdom)
Visible light communications (VLC), is an emerging area of
wireless data communications, which takes advantage of solidstate lighting infrastructure to provide both illumination andhigh speed datalinks. Organic semiconductor materials anddevices, which have unique properties of solution processability,
compatibility with flexible substrates and with large-scale
printing technology, enable a host of new practical applications
including VLC and more importantly have the capability ofaddressing some of key challenges in VLC.
Here we report the demonstration of organic semiconductors
as fast colour-convertors in hybrid semiconductor light sources
for free-space VLC. We show that these materials can improve
bandwidths up to 200 MHz, much higher than are possible withconventional LED phosphors. In addition, we report two datalinks
based on organic optoelectronic devices, one using an OLED as
the transmitter and the other using a PTB7:PC71BM solar cell as
the receiver. Simultaneous functions of data communication andenergy harvesting of the OPV devices have great implications for

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the connectivity of future smart devices, many of which could
become self-powered units as part of the “Internet of Things” [1].
We also demonstrate large area, all-dielectric fluorescentantennas for spatially multiplexed VLC based on nanoimprinted
polymer films. We show that these antennas can emit
highly directional, broadband fluorescence through careful
grating optimisation [2,3], and can be used as high data-ratetransmitters, offering a route to multi-Gbps spatially multiplexed
VLC.
References[1] S. Zhang, D. Tsonev, S. Ghosh, et al., Optica, 2, 607-610 (2015).
[2] S. Zhang, E. R. Martins, A. G. Diyaf, et al., Synthetic Metals,
205, 127-133 (2015).
[3] S. Zhang, G. A. Turnbull and I. D. W. Samuel, Advanced Optical
Materials, 2, 343-347 (2014).

10019-34, Session 7

Electro-optical circuit boards withpolymer optical waveguides: A scalable
technology for in-chassis connections
Marika P. Immonen, TTM Technologies, Inc. (Finland);Jinhua Wu, Hui Juan Yan, Long X. Zhu, Ruizhi Shi, TTM
Technologies, Inc. (China)
Industry is scaling current technologies with new innovations
to enable 56-112Gbps short distance links with copper. Yet,
increasing power consumption, design complexity, fabrication
challenges and cost with requirements for higher packaging
density are pushing industry to seek alternatives for copper.
We have developed PCBs with integrated polymer waveguide
optical layers [1-4]. In this paper, we present optical/electricaldemonstrator with 96-optical channels totaling 2.4 Tb/saggregate capacity. The demonstrator is tested with 300 Gb/s
on-board transceivers, 10-cm- and 20-cm-long embedded
waveguides, and connectors with 90° reflectors in a standard
PCB. The results show BER 1E-12 at 25Gb/s, <0.1 dB/cm
transmission loss and 2.5 dB connector loss. The waveguides
were designed with nominal 50 µm core size and 250 µm spacing
to match OM3/OM4 fiber ribbons from/to the engines. We show
results from another demonstrator with bandwidth density (Gb/s/mm) on-board scaled further 2-4x by increasing optical channel
density with 125 µm or 62.5 µm channel spacing. This minimizes
real estate allocated for optical traces in the board. We envisagehigh density waveguides usable in SiPho packages. Furthermore,
we show results for fabricating standard electrical interconnect
structures e.g. tracing layers, vias, plated vias top/bottom andthrough new optical layers in PCB stack. Material stability andprocess compliance test were carried to investigate lamination
impact to optical loss. We report results in different process
conditions to evaluate new material robustness and long term
reliability. Assembly process compliance test results show that
O/E PCBs pass 4x T=240°C with stable optical loss measured
from polymer waveguides.
[1] S. Chen, F.Pang, K. Li, J.Wu, M. Immonen, X.Zhang, T. Wang
“Long distance optical printed circuit board for 10Gbps opticalinterconnection”, Proc. of SPIE Vol. 8555, Optoelectronic Devices
and Integration IV. (2012)[2] M.Immonen, J.Wu, H.Y.Yan, L.X.Zhu, P.Chen, T.RapalaVirtanen, “Development of Electro-Optical PCBs with Embedded
Waveguides for Data Center and High Performance Applications”,
Proc. of SPIE Vol. 8991, Optical Interconnects XIV. (2014)[3] L.X.Zhu, M.Immonen, J.Wu, H. J.Yan, R. Shi, P. Chen, T.RapalaVirtanen, “Electro-optical line cards with multimode polymer
waveguides for chip-to-chip interconnects”. Proc. SPIE 9270,
Optoelectronic Devices and Integration V. (2014)[4] R. Pitwon, K.Wang, M. Immonen, J.Wu, L.X.Zhu, H.J.Yan,“International Standardisation of Optical Circuit Board#PhotonicsAsia

49

Conference 10019:
Optoelectronic Devices and Integration VI
the range of the compositional grading can greatly enhancethe emitter injection efficiency. The effects of high-low doping
in collector region and the insertion of a thin, undoped InGaAs
layer in the base region of the HPT have also been investigatedin detail. It is found the high-low doping in collector can form
an electric field to aid carrier transport and the intrinsic layer
between emitter and base has functions of reducing knee voltage
and the dark current of HPT. Finally, the HPT under high voltages
are also discussed.

Measurement and Fabrication Procedures”, Proc. of SPIE 9368:
Optical Interconnects XV. (2015)

10019-35, Session 7

Novel long-wavelength mushroom-type
vertical-illumination PIN photodiodeJunchu Wang, Xiaofeng Duan, Yongqing Huang, Kai Liu,
Jiarui Fei, Qingtao Chen, Xiao-Min Ren, Beijing Univ. ofPosts and Telecommunications (China)

10019-37, Session 7

We demonstrate a novel InP-based long-wavelength mushroomtype vertical-illumination PIN photodiode. The photodiodeconsists a PIN structure lattice matched to an InP substrate, it
has five layers: p+ InGaAs contact layer, p+ InGaAsP electron
diffusion barrier layer, intrinsic InGaAs absorption layer, intrinsic
InGaAsP spacer layer and InP collection layer. The operationand performance of the photodiode have been studied using
a two-dimensional, drift-diffusion approach utilizing numericalsimulation software. We introduce the undercut mushroom-type
geometry to overcome the trade-off between the capacitanceand the contact resistance, thereby reducing the RC time
constant.
First of all, we optimize the absorption layer thickness and thearea of the conventional PIN photodiode with the proposed
structure to achieve a higher bandwidth. After that, we optimize
the absorption layer area of the mushroom-type PIN photodiode.
Then we compare the bandwidth of the optimized mushroomtype PIN photodiode and the conventional PIN photodiode.
These two types of photodiodes only differ in the area of
i-InGaAs absorption layer.
The mushroom-type photodiode has shown 35.62% improvement
in bandwidth comparing with the conventional photodiode. The
result shows that at 3 V bias, 1.55 ?m wavelength, the optimized
mushroom-type PIN photodiode and the conventional PIN
photodiode both with 700nm absorption layer have achieved
3dB bandwidth of 29.81 GHz and 21.98 GHz, respectively. To get
rid of the electron diffusion and band discontinuity problems,
two InGaAsP layers are adopted above and below the absorption
layer. The InP collection layer is made 500nm and Gaussian
doped for increasing the electric field as well as minimizing thecontact resistance.

10019-36, Session 7

Performance optimization of Pnp InGaAs/
InP heterojunction phototransistors
Min Zhu, Jun Chen, Soochow Univ. (China)
Development of high sensitivity photodetectors with highspeed and low power consumption has been a main goal
in device research for optical communication applications.
Metal–semiconductor–metal (MSM) photodetectors or p-i-n
photodetectors can provide high-speed, low noise operation but
no internal gain. Avalanche photodiodes (APDs) can achieve highsensitivity due to large internal gain, however, they need highoperation voltage and suffer from avalanche noise. It is therefore
expected that heterojunction phototransistors (HPTs) can provide
an exciting alternative to MSM, p-i-n photodetectors or APDs forthe optical communication, which can offer large optical gain
without the excessive noise resulting from avalanching.

On-chip integration for in-plane video
transmission using visible light
Yongchao Yang, Xumin Gao, Jialei Yuan, Yuanhang
Li, Yongjin Wang, Nanjing Univ. of Posts andTelecommunications (China)
We demonstrate here a wafer-level process to fabricate amonolithic photonic integration of a light emitting diode (LED)with a waveguide and photodiode on a GaN-on-silicon platform.
Both silicon removal and back-side thinning are conductedto achieve suspended device architecture. A highly confined
waveguide that utilizes the large index contrast between GaN
and air is used for the connection between the LED and thephotodiode. Suspended waveguide is considered as an inplane escape cone of the LED, and at the other end of the
waveguide is the photodiode. The photons emitted from the
LED are transported to the photodiode through the suspended
waveguide parallel to the LED surface, leading to an in-plane datatransmission using visible light. The proof-of-concept monolithic
integration paves the way towards the in-plane visible light
communication as well as photonic computation on a single chip.
The highlights are achieved in our present work.
1, We demonstrate a wafer-level process for achieving monolithic
photonic integration of a light-emitting diode with a waveguideand photodiode on a GaN-on-silicon platform. Both siliconremoval and back-side thinning are conducted to achieve asuspended device architecture.
2, Experimental results verify that the light being guided in thesuspended waveguides plays the dominant role in the induced
photocurrent.
3, The integrated system can simultaneously realize lightemission, transmission and photodetection. The photons emitted
from the LED are transported to the photodiode through thesuspended waveguide parallel to the LED surface, leading to inplane data transport using visible light.
4, The wire-bonded chip can achieve in-plane video transmission
via the light emitted from the LED, paving the way towards
in-plane visible light communication as well as photonic
computation on a single chip.

In this paper, a two-terminal Pnp InP/InGaAs HPT with afloating base (2T-HPT) is fabricated, and numerical simulations
are performed to investigate the gain and photoresponse
characteristics. To optimize the optical gain and device
performance, the precise adjustment of the base doping level,
the base width and the compositional grading of base have been
investigated. Properly reducing the base width or increasing

50

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV
Wednesday - Thursday 12–13 October 2016
Part of Proceedings of SPIE Vol. 10020 Optoelectronic Imaging and Multimedia Technology IV

10020-1, Session 1

A high resolution imaging method usedcompressive sensing theory based onarray detector applications (Invited Paper)
Jinping He, Yuchen Liu, Haibo Zhao, Beijing Institute ofSpace Mechanics and Electricity (China)
The military and civil applications call for more stringent
requirements for the accuracy, timeliness and diversity of
information. As a key approach to acquire it, the imaging systems
need a substantial performance increase, such as resolution
enhancement. In the box of Shannon sampling theorem, raising
the resolution means cutting the pixel size of sensor andincreasing the number of pixels. This will enlarge the complexityand difficulty of system nonlinearly. Compressive sensing has
given a revolutionary solution: Based on the sparsity of signal andsub-Nyquist non-coherent compressed sampling, one can recover
the original signal by sparse optimization. It avoids the blind
pursuit of an excessively high-resolution sensor.
The single-pixel camera which is developed by Rice University
in America is just the limit condition used compressive sensing
theory for high resolution imaging. Aiming at the practicalapplication of the optical remote sensing based on array
detectors, this paper founds a novel high resolution imaging
framework with compressive sensing. The imaging mechanismof single-pixel camera can be contained in the framework. Thena novel compressive sensing reconstructed method with energy
compensation is proposed in this framework. The method canovercome the heterogeneity of reconstructed images of singlepixel camera. The simulation experiments deeply discuss the
sampling mechanisms with different sampling rates and different
image patch sizes for reconstruction. The experimental results
show that the image resolution is improved after reconstruction
with a high sampling rate or with a big image patch size. The
imaging method in this paper can supply a technology reference
for compressive sensing application in remote sensing.

10020-2, Session 1

Large field-of-view range-gated laser
imaging based on image fusion
Pengdao Ren, Institute of Semiconductors (China) andUniv. of Chinese Academy of Sciences (China); Xinwei
Wang, Liang Sun, RuiRong You, Yan Zhou, Institute of
Semiconductors (China)
Laser range-gated imaging has great potentials in remote night
surveillance with far detection distance and high resolution,even
if under bad weather conditions such as fog,snow and rain.
However,the field of view(FOV) is smaller than large objects
like buildings,towers and mountains,thus only parts of targets
are observed in one single frame so that it is difficult for target
identification.Apparently, large FOV is beneficial to solve theproblem,but the detection range is not available due to low
illumination density in a large field of illumination matchingwith the FOV.Therefore, a large field-of-view range-gated laser
imaging is proposed based on image fusion in this paper,firstof all,the infrared laser range-gated system is used to acquire
two groups of images with small FOV for five dummies under
different scenarios in the night,one scenario the dummies arearranged in a row at the distance of 110m,another the dummies
distributed in the distance range from 130m to 270m,and thebuilding at 350m is captured as the third group.Then image
fusion is used for generating panoramic through above three

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Follow us on:groups of pictures separately,which is based on the fuction about
panoramic image mosaics in OpenCV 3.0 named Stitcher,and theStitcher fuction is more effective to the night range-gated images
by adjusting match confidence and feature extraction methods.
Compared with the raw panoramic image obtained by rangegated system directly,the fused images have a larger FOV,and
possess more detail information of objects,this illustrates thatimage fusion is effective to expand the view field of range-gatedimaging.

10020-3, Session 1

compressive full-waveform LIDAR with
low-cost sensors
Weiyi Yang, Jun Ke, Beijing Institute of Technology (China)
Full-waveform LIDAR is a method that digitizes the complete
waveform of backscattered pulses to obtain range informationof multi-targets. Compared to conventional LIDAR technique,recording the complete waveform is advantageous to createa dense point cloud for follow-up feature extraction. To obtainhigh-resolution ranging information, conventional full-waveform
LIDAR system are equipped with high-bandwidth sensors,which are expensive. To avoid these expensive sensors, a new
full-waveform LIDAR system based on compressive sensing ispresented in this paper. Compressive sensing is a techniquethat can reconstruct sparse signal with a reduced number ofmeasurements compared to conventional Nyquist-Shannon
sampling technique. To obtain these measurements, pseudorandom sequences are generated by high-rate arbitrary waveformgenerator. Electro-optical modulator is utilized with thesesequences to modulate the non-coherent continuous-wave laser.
Then the backscattered signal becomes a convolution between
the sequences and the range information of multi-targets. Finallya low-bandwidth detector and a low-bandwidth analog-digitalconverter are used to acquire the signal. To reconstruct the highresolution range information, split Bregman iteration algorithm
is employed with the measurements using range signal’s sparseproperty. With experiment, it has been proved that, to achieve
0.30 meter ranging resolution, the temporal sampling distancein a conventional full-waveform LIDAR system needs to be
2 nanosecond, which defines the sample rate as 500 Msps.
However, using compressive sensing method, the same ranging
resolution can be achieved with a 48 Ksps sensor. Experimental
results are also discussed for a full-waveform LIDAR system with
sub-centimeter resolution using inexpensive low-bandwidth
optical sensors.

10020-4, Session 1

Iterative deconvolution methods for ghost
imaging
Wei Wang, Guohai Situ, Shanghai Institute of Optics andFine Mechanics, CAS (China)
Ghost imaging (GI) is a new technique in single-pixel imaging.
It has been demonstrated that GI has applications in various
areas such as imaging through harsh environments and opticalencryption.
Correlation is widely used to reconstruct the object image in
GI. But it only offers the signal-to-noise ratios (SNR) of thereconstructed image linearly proportional to the number ofmeasurements. Here, we develop a kind of iterative deconvolution
methods for GI. With the known image transmission matrix in
GI, the first one uses an iterative algorithm to decrease the error#PhotonicsAsia

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV
between the reconstructed image and the ground-truth image.
Ideally, the error converges to a minimum for Gaussian speckle
patterns when the number of measurements is larger than thenumber of resolution cells. The second technique, GerchbergSaxton (GS) like GI, takes the advantage of the integral propertyof the Fourier transform, and treats the captured data as
constraints for image reconstruction. According to this property,
we can regard the data recorded by the bucket detector as theFourier transform of the object image evaluated at the origin(k = 0). Each of the speckle patterns randomly select certain
spectral components of the object and shift them to the origin in
the Fourier space. One can use these constraints to reconstruct
the image with the GS algorithm. This deconvolution method
is suitable for any single pixel imaging models. Compared toconventional GI, both techniques offer a nonlinear growth of the
SNR value with respect to the number of measurements.

10020-5, Session 1

Development of 36M-pixel x-ray detector
for large field of view and high-resolution
micro-CT
Keiji Umetani, Japan Synchrotron Radiation ResearchInstitute (JASRI) (Japan)

10020-7, Session 2

Dramatic improvements in consumer-grade digital cameras withregard to the resolution and low light sensitivity, together withthe use of synchrotron radiation, make possible a new costeffective technique for large field-of-view and high-resolution
x-ray micro-CT.
Imaging using conventional x-ray sources can only be performedon localized areas, which limits the application of threedimensional (3-D) x-ray micro-CT in the field of lung specimens
with sizes usually in the range of 5–30 mm. An alternative toconventional sources is synchrotron radiation, which can produce
large area collimated beams.
In the x-ray imaging, a phosphor screen converts the x-rays into
light, and the optical image is captured using a digital single-lensreflex camera with high numerical aperture lenses. The camera
used was a 36M-pixel Nikon D800e. The camera’s CMOS sensor
has 7360 x 4912 pixels with a sensor active area of 35.9 mm wide
x 24.0 mm high. Each pixel has dimensions of 4.88 x 4.88 µm. An
equivalent pixel size projected onto the fluorescent screen area isan identical value of 4.88 µm. The x-ray field of view is also 35.9mm x 24.0 mm. Image signals are converted to digital data with a
14-bit format.
Images of a human lung specimen in a plastic bottle with outer
diameter of about 30 mm were obtained for studies of 3-D CT
imaging. In a slice image, the whole cylindrical body of the plastic
bottle was depicted and micro-architectures of the specimen
were visualized with around 7 ?m spatial resolution.

10020-6, Session 2

Underwater three-dimensional rangegated laser imaging based on triangularrange-intensity profile spatial-correlation
method (Invited Paper)
Xinwei Wang, Xiaoquan Liu, Pengdao Ren, Liang Sun,
Songtao Fan, Pingshun Lei, Yan Zhou, Institute of
Semiconductors (China)

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Reflectivity and depth images based on
TCSPCXuejie Duan, Xi‘an Institute of Optics and Precision
Mechanics, CAS (China); Lin Ma, Xidian Univ. (China); Yan
Kang, Xi’an Institute of Optics and Precision Mechanics,
CAS (China); Tongyi Zhang, Xi‘an Institute of Optics andPrecision Mechanics, CAS (China)
We described two optical imaging systems which were used
to acquire the data for three-dimensional images includingreflectivity and depth images of a target when it was illuminatedby a MHz repetition rate pulsed laser source based on timecorrelated single photon counting technique (TCSPC). The
traditional one of which transmitted and received beams path
are separated, and we proposed another one called transceiversystem of which transmit and receive channels are coaxial.
Experimental results produced by both systems showed thatthe transceiver system had more advantages of less noise fromambient light and no limitation about field area of view. Lackof objective lens for transceiver system, counts of collecting
return photons was less, which was prejudicial to constructionof 3D images, thus an advanced one named first photon system
was presented. Structurally speaking, this one is the same astransceiver system, but the control system is different. As a result,the first return photon per pixel was recorded across system
instead of overall return photons per pixel. That’s to say only one
detected return photon is needed for per pixel of this system torebuild 3D images of target with less energy and time.

10020-8, Session 2

An Efficient Anti-occlusion Depth
Estimation using Generalized EPI
Representation in Light Field
Hao Zhu, Qing Wang, Northwestern Polytechnical Univ.
(China)Three dimensional (3D) underwater optical imaging with highresolution and good real time performance is important formarine automatic navigation, scientific research, aquaculture,engineering, archaeology, and natural resources exploration.
Underwater 3D range-gated imaging can extend the detection
52

range by a factor of about 3 over conventional underwater stereo
cameras with suppressing water backscattering and filtering
backgrounds, and also has greater potentials in real-time highresolution imaging than 3D laser scanning. Up to now, there are
two approaches of underwater 3D range-gated imaging. One
is realized based on many gate images by time slicing, and theother is realized by spatial correlation of two gate images withtrapezoidal range-intensity profiles. It has proved that the latterhas a better real time capability. In this paper, a triangular-rangeintensity profile spatial correlation method is used for underwater
3D range-gated imaging. Different from the trapezoidal method,in our method gate images have triangular range-intensity
profiles by the convolution of laser pulses and gate pulses withequal pulse width and gate time, and the range resolution is
improved by a factor of 3. A 3D underwater range-gated laser
imaging system is established where a 532nm pulsed laser andan ns-scaled gated ICCD are respectively utilized as illuminatorand detector. In experiment, 3D images of artificial fishes, fish
net and balls are obtained with mm-scaled resolution, and thus
target sizes and distances can be measured. In addition, 3D
imaging with video frame rates can also be realized by interframe correlation. The research of this paper is beneficial to 3D
real-time high-resolution underwater imaging.

·

Light field cameras have been rapidly developed and are likely
to appear in mobile devices in near future. It essential to develop
efficient and robust depth estimation algorithm for mobile
applications. However, existing methods are either slow or lack ofadaptability to occlusion such that they are not suitable to mobilewww.spie.org/pa·

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV
computing platform.
In this paper, we propose the framework of the generalized
epipolar plane image (GEPI) representation in light field. In thisframework, the EPI is obtained by shearing a 2D slice in 4D
space and traditional obtention is just a special case sheared inhorizontal or in vertical. We formulate the GEPI using two linear
functions in mathematic, and the 2D slice in any angle which
satisfies the conditions can be called a GEPI. Theoretically, each
GEPI can be used for depth estimation, however it does nothold due to the occlusion. By modeling the occlusion in lightfield, there is at least one GEPI representation which is free ofocclusion. We propose to select the best occlusion-free GEPI inlight field, and applies an efficient local depth estimation method.
The performance of the proposed algorithm is evaluated in themost popular light field dataset, and compared to the state-ofthe-arts. The experimental results demonstrate that the proposed
algorithm outperforms the existing local methods especiallyin occlusion areas, and comparing to the global methods, ouralgorithm can achieve high-quality depth map under a low timecomplexity.

10020-9, Session 2

Realization of three dimensional thermal
infrared imaging by structured light andbinocular vision
Debing Zeng, Saint Peter’s Univ. (United States); JunhuaSun, BeiHang Univ. (China)
Thermal infrared imaging has broad applications in various
fields. However, two dimensional infrared imaging has limited
its applications for its lack of spatial information while thecurrent three dimensional imaging in the visible spectrum
does not provide thermal infrared information. By utilizing thecoded structured light and binocular stereo vision, a 3D infrared
imaging system is proposed and constructed with two visiblelight cameras and one infrared camera together with a digitalprojector. Multimodal sensors are integrated to fuse the spatial
and thermal infrared information that are acquired throughthe aforementioned three independent cameras, providing
the geometrical size and surface temperature of the target
simultaneously. The 3D shape is generated with the involvementof structured light technique, and the registration between
different sensors is accomplished based on trifocal tensor andbilinear interpolation. Two sets of experimental investigations
with a storage box and a rudder model respectively were
undertaken with the system. The results show that theregistration of 3D geometric information and 2D infrared image
as well as dealing with the resolution difference between thethree cameras is successful. The proposed system is non-contact
and free of human-intervene, and provides technical reference
to its potential applications in industrial detection and medical
diagnosis alike.

10020-10, Session 2

Integral imaging-based optical refocusingof 3D objects on their full-depth by using
local [delta]-periodic functions andsubdivided-elemental images
Lingyu Ai, Holodigilog Research Ctr. (Korea, Republic of);
Eun-Soo Kim, Holodigilog Human Media Research Ctr.
(Korea, Republic of)
The need for the optical three-dimensional (3-D) refocusing
method is getting strong since it allow us to optically reconstruct
the refocused 3-D images on their real depth with the light fields

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captured from the input 3-D objects. A periodic ?-function array(PDFA) based method is proposed for 3-D refocusing by use of
the inherent sifting property of the PDFA, however, this method
has a critical problem that it works only for the 3-D objects
located within a specific pickup range That is, the 3-D objects
to be imaged should be positioned within a so-called effectivecapturing-zone (ECZ).
Thus, an approach for optical refocusing of three dimensional (3D) objects on their real depth without a pickup-range limitation
based on subdivided-elemental image arrays (sub-EIAs) and local
periodic ?-function arrays (L-PDFAs) is proposed. The captured
EIA from the 3-D objects locating out of the conventional
effective pickup-range, is divided into a number of sub-EIAs
depending on the object distance from the lens array. Then,by convolving these sub-EIAs with each L-PDFA whose spatial
period to that of the sub-EIA, arrays of spatially-filtered sub-EIAs(SF-sub-EIAs) for each object depth can be uniquely extracted.
From these arrays of SF-sub-EIAs, 3-D objects can be opticallyreconstructed to be refocused on their real depth. Operational
principle of the proposed method is analyzed based on rayoptics. In addition, to confirm the feasibility of the proposed
method in the practical application, experiments with test objects
are carried out and the results are comparatively discussed withthose of the conventional method.

10020-11, Session 3

Single-pixel hyperspectral imaging (Invited
Paper)
Jinli Suo, Yuwang Wang, Liheng Bian, Ziwei Li, Tsinghua
Univ. (China)
Multispectral imaging is extremely useful and vital for surveying
scenes and extracting detailed information. Conventional
multispectral imaging methods detect photons of a 3D
hyperspectral data cube separately either in the spatial or
spectral dimension using array detectors, and are thus photon
inefficient and spectrum range limited. Besides, they are usuallybulky and highly expensive. To address these issues, this paper
presents multispectral imaging techniques using a single bucket
detector, to take full advantage of its high sensitivity, wide
spectrum range, low cost and light weight. Two mechanisms
are proposed: (i) utilizing the gap between the speed of theillumination structuring and single pixel recording, we multiplex
the spectral information either in temporal or frequency manner.
(ii) utilizing the relative redundancy of illumination patterns’
resolution with respect to that of the reconstructed images, we
multiplex the spectral information in different positions of a highresolution spatial light modulator. The effectiveness of these two
strategies are both validated experimentally.

10020-12, Session 3

Spatial-spectral data redundancy
requirement for Fourier ptychographic
microscopy
Jiasong Sun, Yuzhen Zhang, Nanjing Univ. of Science andTechnology (China); Qian Chen, Nanjing Univ of Scienceand Technology (China); Chao Zuo, Nanjing Univ. of
Science and Technology (China)
Fourier ptychographic microscopy (FPM) is a new computational
super-resolution approach, which can obtain not only thecorrect object function, but also the pupil aberration, the LED
misalignment, and beyond. Although many state-mixed FPM
techniques have been proposed to achieve more accurate andefficient recovery in the past few years, little is known that
their reconstruction performance highly depends on the data

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV
redundancy in both spatial and spectral domains. Generally, atleast 35% aperture overlapping percentage in the Fourier domain
is needed for a successful reconstruction using ordinary FPM
method. However, the data redundancy requirements for thosestate-mixed FPM schemes are largely remained unexploreduntil now. In this paper, we explore the spatial and spectral
data redundancy requirements for the FPM recovery process tointroduce spatial-spectral sampling criteria for the conventionaland state-mixed FPM techniques. Moreover, an upsampled FPM
method is proposed to solve the pixel aliasing problem, andan alternative spectral subsampled FPM scheme is introduced
to get rid of the complexity of decoherence and achieve theexpected recovery quality with reduced data quantity. All the
proposed methods and spatial-spectral sampling criteria arevalidated with both simulations and experiments, and our results
show that state-mixed techniques cannot provide a significant
performance advantage since they are much more sensitive todata redundancy. This paper provides both the guidelines fordesigning the most suitable FPM platform and the insights for thecapabilities and limitations of the FPM approach.

have studied the calibration of intrinsic parameters in monocular
light field or the registration of multiple calibrated cameras, but
the work in MVLF has not been concerned.

10020-13, Session 310020-15, Session 3

Reconstructing spectral reflectance fromdigital camera through samples selection

An effective rectification method forlenselet-based plenoptic cameras

Bin Cao, Ningfang Liao, Wen-Ming Yang, Beijing Instituteof Technology (China); Haobo Chen, Beijing Institute ofTechnology (China) and Shenzhen Research Institute(China)Imaging spectrophotometers have been widely studied in
the reconstruction of the spectral information of the samples.
But they require shot several times and long exposure time.
Digital cameras have the advantages of higher resolution,shorter exposure time. Researchers try to recovery spectralreflectance from digital camera outputs, such as pseudo-inverse
method, wiener estimation, principal component analysis, andindependent component analysis. Most of above methods, thecamera’s responsivity needs to be instrumentally measured while
it is often inconvenient. The accuracy of reconstructed spectralreflectance is affected directly by the uniform characteristics ofthe training samples and test sample. In this study, we propose
a method to reconstruct spectral reflectance from RGB imagesby averaging the selected reflectance of training samples groupwhose color difference are smaller with the camera outputs ofeach pixel (testing sample) respectively, and it doesn’t requirepriori knowledge of camera’s spectral responsivity. The odd andeven sequence numbers of 1269 Munsell color chips were usedas training samples and test samples respectively. Different
selected numbers of training samples were investigated. The
spectral reflectance estimation are evaluated with absolute error,
root mean squared error, standard deviations, and Goodness-ofFit Coefficient. Experimental results prove the reliability of the
proposed methods. Especially due to the nature of the proposed
method, the reconstructed spectral reflectances are among 0-1,
which make them have actual physical meanings.

light field camera self-calibration andregistration

The Lenselet-Based Plenoptic has recently drawn a lot of
attention in the field of computational photography and the
additional information inherent in a light field allows a wide range
of applications. Some preliminary processing of the raw image issignificant before further operations.
In this paper, we present a novel method for the rectification of
the rotation of the raw image, caused by imperfectly positionof microlens array relative to the sensor plane in commerciallyavailable Lytro plenoptic cameras. The key of our method is
to locate each center of the macroimage, a small portion of
the image projected by a microlens according to vignetting.
A structuring element was applied to probe the raw image tofind subimages where the centers of them have the maximum
pixel values compared to the peripheries of the subimages.
If the structuring element exactly fits inside a subimage, thebrightest pixel -- the center of this subimage -- is regarded as
the center of the corresponding macroimage. The error of thecenter coordinate estimates can be corrected and the angle ofrotation can be computed via a subsequent line fitting. We apply
our algorithm on two raw images captured with different Lytro
cameras and the angle of rotation are -0.3600° and -0.0621°
respectively. The rectified raw image is used in further operations,such as extraction of the sub-aperture Images and epipolar
images. The experimental results show that our method canaddress the problem of rotation of raw image efficiently.

10020-16, Session 3

Hanglin Cheng, Qun Hao, Yao Hu, Jie Cao, Shaopu Wang,
Lin Li, Beijing Institute of Technology (China)

Zhe Ji, Chunping Zhang, Qing Wang, Northwestern
Polytechnical Univ. (China)
Monocular light field is famous for the post processing capability
in 4D light field, but its limited field of view is a difficult issue
to deal with. As the rise of the Multiview light field (MVLF), theregistration of MVLF become a new solution and the calibrationof MVLF is a key step before the registration. The previous work
SPIE Photonics Asia

Jing Jin, Yiwei Cao, Weijia Cai, Wanlu Zheng, Ping Zhou,
Southeast Univ. (China)

Design of optoelectronic imaging systemwith high resolution and large field-ofview based on dual CMOS

10020-14, Session 3

54

In this paper, we propose a self-calibrating method to get thepose of light field (LF) and the interval parameters of cameras
at the same time. At first, we represent the LF structure as a
two-parallel-plane (TPP) model with 5 intrinsic parameters,
which describe the proportion and shift of the two planes.
Then the 3D projective transformation from the rays to thereconstructed points in LF is studied. Next, with the constraintsof ray-ray correspondence in different LFs, we can relate thepose information into the model. Based on all the constraints
mentioned before, we can deduce the linear initialization of theparameters, and then a nonlinear refine process is added to
optimal the solution. Finally, the different LFs are registered as
one with the more accurate parameters. To validate the method,
we employ the experiment on both simulated data and a physicallight field camera. The stitching result and 3D point clouds
registration error of MVLF demonstrate the high performance ofthe proposed model.

·With the advantages of high resolution, large field of view andcompacted size, optoelectronic imaging sensors are widely usedin many fields, such as robot’s navigation, industrial measurement
and remote sensing. Many researchers pay more attention to
improve the comprehensive performances of imaging sensors,
including large field of view (FOV), high resolution, compact size

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Conference 10020:
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and high imaging efficiency, etc. One challenge is the tradeoff
between high resolution and large field of view simultaneously
considering compacted size. In this paper, we propose an
optoelectronic imaging system combining the lenses of shortfocus length and long focus length based on dual CMOS tosimulate the characters of human eyes which observe object
within large FOV in high resolution. We design and optimize
the two lens, the lens of short focus length is used to search
object in a wide field and the long one is responsible for highresolution imaging of the target area. Based on a micro-CMOS
imaging sensor with low voltage differential transmission
technology-MIPI (Mobile Industry Processor Interface), we
design the corresponding circuits to realize collecting opticalinformation with high speed. The advantage of the interface isto help decreasing power consumption, improving transmission
efficiency and achieving compacted size of imaging sensor.
Meanwhile, we carried out simulations and experiments to testify
the optoelectronic imaging system. The results show that the
proposed method is helpful to improve the comprehensive
performances of optoelectronic imaging sensors.

has been developing variously, for example, getting the dynamic
luminance information from a video, taking a panoramic photo bya pair of fish-eye lens, what’s more, classifying and segmenting
the complex scenes by the point cloud data.

10020-17, Session 4

Xueguan Zhao, Xiu Wang, Beijing Academy of Agriculture
and Forestry Sciences (China) and National Research Ctr.
of Intelligent Equipment for Agriculture (China) and Key
Lab. of Agri-informatics Ministry of Agriculture (China);
Cuiling Li, Beijing Academy of Agriculture and Forestry
Sciences (China)

Behavior analysis of video object incomplicated background (Invited Paper)
Wenting Zhao, Shigang Wang, Wei Wu, Yang Lu, Yunpeng
Hu, Jilin Univ. (China)
This paper aims to achieve robust behavior recognition of video
object in complicated background.
Features of the video object are described and modeledaccording to the depth information of three-dimensional video.
Multi-dimensional eigen vector are constructed and used toprocess high-dimensional data.
Stable object tracing in complex scenes can be achieved withmulti-feature based behavior analysis, so as to obtain the motion
trail.
Subsequently, effective behavior recognition of video object isobtained according to the decision criteria.
What’s more, the real-time of algorithms and accuracy of analysis
are both improved greatly. The theory and method on the
behavior analysis of video object in reality scenes put forward
by this project have broad application prospect and importantpractical significance in the security,terrorism, military and manyother fields.

10020-18, Session 4

The efficient model to define a single lightsource position by use of high dynamic
range image of 3D scene
Xu-yang Wang, Changchun Univ. of Science andTechnology (China); Dmitry D. Zhdanov, Igor S. Potemin,
ITMO Univ. (Russian Federation); Ying Wang, Han Cheng,
Changchun Univ. of Science and Technology (China)
One of the challenges of augmented reality is a seamless
combination of objects of the real and virtual worlds. One ofthe object types are light sources. In this paper we consider thesolution to restore the coordinates of a light source in the realscene with use of High-Dynamic Range Image (HDRI). The firstlight source position algorithm was proposed by Zheng in 1991,
in order to measure the azimuth angle of the light source, thisalgorithm analyzes the image containing the marker according
to the shadow information of image contour line. In these days,
the problem of determining the coordinates of the light source
can be based on the research about light source reconstruction

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We suggest a measurement and computation models forreconstruction of light source position. The model is based on
the dependence of luminance of the small size diffuse surface
directly illuminated by point like source placed at a shortdistance from the observer or camera. The advantage of thecomputational model is the ability to eliminate the effects ofindirect illumination. One more advantage is that only relative
but not absolute values are necessary, and the measurement
is worked easily. The paper presents a number of examples toillustrate the efficiency and accuracy of the proposed method.

10020-20, Session 4

X-ray technique application in evaluating
the quality of tomato seeds

The objective of this work was that to investigate the applicationof X-ray technique in evaluating the quality of tomato seeds
and in verifying the effectiveness of the X-ray test to detectdamage or abnormalities in tomato seed structure associatedwith germination. In this paper, using the x-ray camera directly
to generate digital images, the radiation exposure conditionof 18 Kv generated more precise seed images. The work was
carried out with five seed lots each of Xia Lang were used, one
hundred seeds per lot were exposed to X-radiation and visuallyclassified into four categories according to the proportion
between the area occupied by the embryo and endosperm in
relation to the total cavity area in the internal seed structure,e.g. 0, < 40%, 40-65% and 100%. In addition, there is an damage
internal structural. X-ray tested seeds were submitted to thegermination test to detect possible associations between seedanatomy and its corresponding seedling, and non-germinatedseed. Germination test at 25ºC for 20 days. The experiments
show that crack in the cotyledon region negatively affected
seedling shoot development. These parameters correlate wellwith the morphology of 14-day old seedlings, the percentage ofseeds germination was 32% higher after hand selection based on
X-ray evaluation. The results of this work showed an association
between the morphological information provided by the X-ray
test and the standard germination test, indicating its potential tobe applied on tomato seed quality assay.

10020-19, Session Post

Research on key technology of yacht
positioning based on binocular parallax
Wei Wang, Ping Wei, Beijing Institute of Technology(China)Yacht has become a fashionable way for entertainment. However,to obtain the precise location of a yacht docked at a port has
become one of the concerns of a yacht manager. To deal with thisissue, we adopt a localization method based on the principle ofbinocular parallax in this paper.
Binocular parallax uses cameras to get multi-dimensinonal
perspective of a yacht based on geometric principle of imaging.
on access to image pixels between the location of deviation
is evaluated to get spatial location information of the yacht.

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Conference 10020:
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10020-29, Session Post

Moreover, the central region of distortion image will get abetter correction than border area from the imaging principalof fisheye camera. Therefore,through measuring one hundredhousehold cars, the installation height for front logo:65cm, 95cm
for rear-view mirror and 58cm,84cm,93cm for rear license plate
respectively were taken as experimental installation height.
Through the linear fitting for corrected calibration plate images
which were taken at different installation angle,the suggested
installation angle for different mounting position was given.
Through analyzing the principal of current bird-eye imagetransformation,the factor that result in varying grid size wasfound out.Therefore,a bird-eye image transformation method thatthe first transformation made with central calibration plate while
the second transformation was made by left and right plates was
proposed. Experiment indicated that the proposed method canweaken the existing problem of bird-eye image effectively.

Propagation characteristics of orbital
angular momentum for remote imaging

10020-32, Session Post

In order to simplify the yacht localization problem, we install
LED light indicators on a yacht. These LED flashes at a certain
frequency during day time and night time. After getting thelocation of the LEDs, locating the yacht is easy. Compared withother traditional localization methods, this method is simpler andeasier to implement.
In this paper,we study the yacht locating method using LED
indicators. Simulation experiment is done for an object in the
distance of 30 meters. We also analyze noise influence, andcomparing our method with others using locating results.The
experimental result shows that our method is feasible and easy to
implement with a small 10% positioning error.

Li Lu, Air Force Early Warning Academy (China)
The research of orbital angular momentum (OAM) in light beamgradually is becoming an attractive area for quantum information,
optical micromanipulation, and optical communication
applications. Compared to other conventional methods, OAM
can offer new degrees of freedom in addition to traditional linear
momentum. Recent years, some researchers verified that OAM
can promisingly be used in the low frequency radio domain andnot be restricted to the optical frequency range. According to theclassical electrodynamics theory, the electromagnetic (EM) field
can radiate both energy and angular momentum. The energy of
the EM field is associated with translational dynamics, referred
to as linear momentum. The angular momentum is connected
to rotational dynamics, which can be decomposed into two
components: spin angular momentum (SAM) and OAM, theformer is associated with polarization, the latter leads to helicalphase fronts. L. Allen had studied detailed that generations andtorque effects of orbital angular carried by a laser beam. Suchbeams usually have the characteristics on-axis phase singularity
and amplitude nulls at the centers of beams, called optical vortex.
Similar to optical vortex, angular momentum carried by the wave
in microwave wavelength reveals EM vortex features. The studies
on applying OAM to remote imaging have little been proceeded.
In this paper, the propagation charactistics of OAM in EM vortex
waves are analyzed, and the applications of remote imaging
required to detect OAM in EM vortex waves are descripted
and discussed. The results show OAM has the capability to
be used for remote imaging system and can be enhanced theperformance of target detection.

10020-31, Session Post

Image preprocessing for vehicle
panoramic system
Ting Wang, Liguo Chen, Soochow Univ. (China) and
Collaborative Innovation Ctr. of Suzhou Nano Science andTechnology (China)
The research on image preprocessing for vehicle panoramicsystem was carried out owing to the problem that distortion exist
in panoramic image stitching. Firstly, the fundamental role thatimage preprocessing(distortion image’s correction and bird-eye
image transformation ) played in panoramic vision was found out.
Afterwards,the fisheye camera was calibrated with Hyperboloid
model that proposed by Scaramuzza. Through the comparison
with conventional perspective camera, a procedure for distortion
image’s correction was given. As four cameras were mounted
in different positions(the front logo,the left and right rear-view
mirror and the rear license plate), different field of view(FOV) andinstallation height may have effects in terms of image correction.

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Simultaneous localization and mappingof mobile robot using a pose graph and astereo camera
Junqin Lin, Baoling Han, Ming Zhao, Xinliang Zhong,Jiahang Zhao, Beijing Institute of Technology (China)
Localization algorithm based on machine vision is a hot topic in
the field of intelligent mobile robot?Visual localization can help
the mobile robot obtain the current position and orientation
information accurately, ensuring that the mobile robot canaccomplish the appointed task safely and efficient.
A fast method for mobile robot 3D SLAM was presented
to address the problem of 3D modeling in complex indoor
environment. Environment texture and 3D data were captured
by sensor of Bumblebee2 that made in Canadian Point Grey
Company. In this paper, through using the stereo matched
SIFT features point as environmental visual landmarks. In orderto reduce the complexity of matching in the SIFT algorithm,
using 32-dimensional feature descriptors instead of the original
128-dimensional feature descriptors describes the SIFT image
features.
According to the camera calibration model and the image
feature extraction and matching procedure, the association
between two 3D point clouds was established. On the basis of
the RANSAC algorithm, the correspondence based iterative
closest point arithmetic model was solved to realize the robot’s
precise localization effectively. With the key frame-to-frame
selection mechanism, the 3D grid map method and the uniquenormal characteristic of a spatial point were used for maintaining
and updating the global map. The global optimization is used toobtain the best position of the frames to reduce the accumulative
error which caused by the matching error and the mismatching
between two frames.
Experimental results demonstrate the feasibility and effectivenessof the proposed algorithm in the indoor environment.

10020-34, Session Post

Online multi-object tracking with behavior
learning
Le Dan, Zinan Lin, Xiangyang Ji, Qionghai Dai, Tsinghua
Univ. (China)
Multi-object tracking(MOT) which performs the tracking ofmultiple targets in video sequences plays an important role innumerous computer vision tasks. MOT draws more and more
attention due to its wide applications in various scenarios, suchas pedestrian surveillance, traffic safety, robot navigator andautomatic drive. Online MOT can be stated as to associate thewww.spie.org/pa·

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Conference 10020:
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noisy and ambiguous object detections in current frame withpreviously tracked objects. In order to resolve the ambiguity
in data association, cues such as appearance and dynamics
are employed. Though these cues have improved the MOT
performance significantly, all these methods still suffer severe
identity switch which is unacceptable in applications likepedestrian surveillance and robot navigator. Meanwhile, ID switch
rarely happens in human tracking. People may lost the targets
they track for a little while but merely confused with the objects
they track under common scenarios. From this point of view, we
try to improve MOT performance by addressing the difference
between existed methods and human tracking. For example,
targets tend to move smoothly and the bounding box tends tobecome larger when the object is heading towards the camera.
Unfortunately, these behavior patterns are mostly semantic andhard to model directly. In this work behavior learning basedon neural network is first introduced to provide a semantic
feature other than traditional appearance and dynamics. We
Perform behavior learning on both ground truth and specifictracking result to generate global and local prediction. Accurate
prediction for each object is produced by combining global andlocal prediction. Our experimental evaluation on benchmark
datasets confirms that, by using behavior learning, the ID switch
numbers is significant reduced while the recall rate is improved orremained the same level.

10020-35, Session Post

Studies on filtered back-projection
imaging reconstruction based on amodified wavelet threshold function
Zhong Ren, Jiangxi Science and Technology Normal Univ.
(China) and Nanchang Univ. (China); Guodong Liu, Jiangxi
Science and Technology Normal Univ. (China)
Although the filtered back-projection (FBP) reconstruction
algorithm has been widely applied into the biomedical imaging,the complete data should be used in order to obtain the highquality of image. In practice, the original data are easily pollutedby all kinds of noises, which will seriously impact the image
reconstruction quality of the biomedical imaging. Therefore,
the removing of noises interference is a key step of improving
the image quality of imaging reconstruction. In this paper,
the wavelet threshold denoising method was used into thefiltered back-projection algorithm of imaging reconstruction.
To overcome the drawbacks of the traditional soft- and hardthreshold functions, a modified wavelet threshold function
was proposed. The modified wavelet threshold function has
dual threshold values and dual factors. To verify the feasibilityof the modified wavelet threshold function, the standard test
experiments were performed by using the software platform
of MATLAB. Experimental results show that the filtered backprojection reconstruction algorithm based on the modified
wavelet threshold function has better reconstruction effectbecause of more flexible advantage. Moreover, the modified
wavelet threshold function overcomes the drawbacks of pseudo
Gibbs oscillation for the hard-threshold function, and reduces
the deviation between the reconstructed image and the original
image. Therefore, the filtered back-projection reconstruction
algorithm based on the modified wavelet threshold function has
great potential value in the image reconstruction of biomedical
imaging.

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10020-36, Session Post

Experimental study of polarization
imaging characteristics on various
materials
Sike Bai, Duan Jin, Changchun Univ. of Science andTechnology (China); Yizhuo Lu, Jinlin Univ. (China); Xinxin
Wang, Tianwei Chen, Changchun Univ. of Science andTechnology (China) and Jinlin Univ. (China)
Polarization imaging has a series of advantages where ordinary
imaging has no, especially to highlight target in a kind of special
background, which is a good auxiliary means of studying theearth’s surface and atmosphere. Under the three typical bands
which are red light band, green light band and blue light bandin the range of visible light, to adopt the method of calculating
the stokes vector, polarization experiments are carried out in six
kinds of materials which are lawn, stone, asphalt surface, glass,rubber and iron plate respectively, and degree of polarizationand polarization degree of contrast are analyzed in details, theexperimental results show that there is all a very big concern
between the polarization imaging features and the material,
imaging band, observing time, so polarization imaging has animportant significance in target recognition and remote sensing
detection.

10020-37, Session Post

Generation of high-dynamic range image
from digital photo
Ying Wang, Changchun Univ. of Science and Technology(China); Igor S. Potemin, Dmitry D. Zhdanov, ITMO
Univ. (Russian Federation); Xu-yang Wang, Han Cheng,
Changchun Univ. of Science and Technology (China)
The traditional digital camera equipment can only capture
two orders of magnitude range image. General image can only
contain 256 levels which are far away to denote the dynamic
range of the natural scene luminances. Thus it is very importantto build the High Dynamic Range Image (HDRI). HDRI records
the luminance of the real scene. It can be used in many modern
applications such as digital photography, game development,
medical imaging, remote sensing satellites imaging, virtual
prototyping etc.
The task of conversion of ordinary 256 level image to HDRI
has different solutions. For example, Mann and Picard used thelinear function to simulate the response curve; Debevec andMalik employed a number of images with accurate exposure;
Mistsunaga and Nayar used polynomial approximation to simulate
the response curve. In any case, the response curve must be
reduced to single units of the relative aperture and exposure time
and then calibrated to standard light source.
The article proposes the camera calibration method based on theclear sky as the standard light source and takes sky luminancefrom CIE sky model for the corresponding geographicalcoordinates and time. The proposed method can be applied toany ordinary digital camera to convert the ordinary image to
HDRI. The only requirement to the camera is to save values of therelative aperture and exposure time. The article considers basealgorithms for getting real luminance values and corresponding
programmed implementation of the algorithms. Moreover,examples of HDRI reconstructed from ordinary images illustrate
the article.

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV

10020-38, Session Post

A chest-shape target automatic detection
method based on Deformable Part Models
Mo Zhang, Weiqi Jin, Li Li, Beijing Institute of Technology(China)Automatic weapon platform is one of the important research
directions at domestic and overseas, it needs to accomplish fast
searching for the object to be shot under complex background.
Therefore, fast detection for given target is the foundation offurther task. Considering that chest-shape target is common
target of shoot practice, this paper treats chest-shape target as
the target and studies target automatic detection method basedon Deformable Part Models. The algorithm computes Histogramsof Oriented Gradient(HOG) features of the target and trainsa model using Latent variable Support Vector Machine(SVM);
In this model, target image is divided into several parts thenwe can obtain foot filter and part filters; Finally, the algorithm
detects the target at the HOG features pyramid with methodof sliding window. The running time of extracting HOG pyramidwith lookup table can be shorten by 36%. The result indicatesthat this algorithm can detect the chest-shape target in naturalenvironments indoors or outdoors. The true positive rate ofdetection reaches 76% with many hard samples,and the false
positive rate approaches 0. Running on a PC (Intel(R)Core(TM)i5-4200H CPU) with C++ language, the detection time ofimages with the resolution of 640 480 is 2.093s. According to TI
company run library about image pyramid and convolution forDM642 and other hardware, our detection algorithm is expected
to be implemented on hardware platform, and it has application
prospect in actual system.

10020-39, Session Post

Image restoration is a classical and crucial inverse problem in
optical imaging. Images often inevitably suffer from the blurring
effect due to atmospheric turbulence, an out of focus camera,or relative motion between the camera and the object in image
acquisition or transmission processes. Conventional image
deblurring methods often deal with the degraded images asa whole while ignoring that an image contains two different
components: cartoon and texture. Recently, total variation (TV)based image decomposition methods are introduced into image
deblurring problem. However, these methods often suffer fromthe well-known stair-casing effects of TV. In this paper, a new
cartoon-texture decomposition based sparsity regularization
method is proposed for non-blind image deblurring. Based onimage decomposition, it respectively regularizes the cartoon
with a framelet-domain-based sparse prior regularizationand the texture with the sparsity of discrete cosine transformdomain. Then an adaptive alternative split Bregman iteration is
proposed to solve the new multi-term sparsity regularization
model. Experimental results demonstrate that our method canrecover both cartoon and texture of images simultaneously andtherefore can improve the visual effect. In addition, the objective
assessment indexes of the deblurred images show that our
method can greatly improve both the PSNR and the SSIM values
than TV decomposition methods and other undecomposed
methods.

10020-41, Session Post

The design of red-blue 3D video fusion
system based on DM642
Rongguo Fu, Hao Luo, Guiyuan Wang, YiFang Wei, Jin
Lv, Hao Zhang, Shu Feng, YaFeng Qiu, Nanjing Univ. of
Science and Technology (China)

The technique of small target detection is the key technique ofthe electro-optical detecting system, especially in low signalto-noise and low contrast images. The temporal and spatial
distribution features of the small target, noise and the contour
are proposed in this article. A detection algorithm of single
frame small target based on NSCT is proposed. The original
image is decomposed by NSCT transform to obtain the details
characteristics of multi-scale and multi-direction. Then, thelow frequency image is filtered by median filter to remove
residual target. In the finer scale, the noise coefficients willattenuate quickly but the contours and textures coefficients
will be relatively stable, so the contours and textures can be
distinguished by the correlation coefficient between adjacentscales. The weight coefficient of the high frequency sub-bands
is adjusted according to the sub-bands correlation to suppress
target. The background image obtained by inverse NSCTtransform is subtracted from an original image. Finally, adaptive
threshold and region growing is applied are used on backgroundimage. Through simulation experiment?the method can detect
the single frame small target quickly and accurately.

Aiming at the uncertainty of traditional 3D video capturing
including camera focal lengths, distance and angle parameters
between two cameras, a red-blue 3D video fusion system basedon DM642 hardware processing platform is designed withthe parallel optical axis. In view of the brightness reduction of
traditional 3D video, the brightness enhancement algorithm
based on human visual characteristics is proposed and theluminance component processing method based on YCbCr color
space is also proposed.The BIOS real-time operating system isused to improve the real-time performance. The video processing
circuit with the core of DM642 enhances the brightness of theimages, then converts the video signals of YCbCr to RGB andextracts the R component from one camera, so does the othervideo and G, B component are extracted synchronously, outputs
3D fusion images finally.The real-time adjustments such astranslation and scaling of the two color components are realized
through the serial communication between the VC softwareand BIOS. The system with the method of adding red and blue
components reduces the lost of the chrominance components
and makes the picture color saturation reduce to more than 95%
of the original.Enhancement algorithm after optimization to
reduce the amount of data fusion in the processing of video isused to reduce the fusion time and watching effect is improved.
Experimental results show that the system can capture imagesin near distance, output red -blue 3D video and presents the niceexperiences to the audience wearing red-blue glasses.

10020-40, Session Post

10020-42, Session Post

A cartoon-texture decomposition-based
image deburring model by using frameletbased sparse representation

High-resolution three-dimensional
imaging with compress sensing

Detection algorithm of single-frame small
target based on NSCTWei Zhang, Wei Chen, Beihua Univ. (China)

Huasong Chen, Xiangju Qu, Ying Jin, Zhenhua Li, Anzhi
He, Nanjing Univ. of Science and Technology (China)

58

SPIE Photonics Asia·

Jingyi Wang, Beijing Institute of Technology (China); Jun
Ke, Beijing Institute of Technology (China)
LIDAR three-dimensional imaging technology have been used inwww.spie.org/pa·

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV
many fields, such as military detection. However, LIDAR require
extremly fast data acquisition speed. This makes the manufactureof detector array for LIDAR system is very difficult. To solve thisproblem, we consider using compress sensing which can greatly
decrease the data acquisition and relax the requirement of adetection device. To use the compressive sensing idea, a spatial
light modulator will be used to modulate the pulsed light source.
Then a photodetector is used to receive the reflected light. A
convex optimization problem is solved to reconstruct the 2D
depth map of the object.
To improve the resolution in transversal direction, we use
multiframe image restoration technology. For each 2D piecewiseplanar scene, we move the SLM half-pixel each time. Then theposition where the modulated light illuminates will changed
accordingly. We repeat moving the SLM to four different
directions. Then we can get four low-resolution depth maps
with different details of the same plane scene. If we use all of
the measurements obtained by the subpixel movements, we
can reconstruct a high-resolution depth map of the sense. A
linear minimum-mean-square error algorithm is used for thereconstruction.
By combining compress sensing and multiframe image
restoration technology, we reduce the burden on data analyseand improve the efficiency of detectio. More importantly, we
obtain high-resolution depth maps of a 3D scene.

10020-43, Session Post

Range-gated underwater laser imaging
enhancement based on contrast-limited
adaptive histogram equalization
Liang Sun, Xinwei Wang, Xiaoquan Liu, RuiRong You,
Pengdao Ren, Pingshun Lei, Jun He, Yan Zhou, Yuliang Liu,
Institute of Semiconductors (China)
Underwater range-gated laser imaging is widely used forunderwater target detection with significantly suppressing
seawater backscattering and improving the quality of underwater
images. However, it still has some problems like un-uniform light,
low brightness and contrast. To solve the problems, a variant ofadaptive histogram equalization called contrast limited adaptive
histogram equalization (CLAHE) is proposed in this paper.
It differs from traditional histogram equalization (HE) in therespect that the adaptive method computes several histograms,
corresponding to a distinct section of the image respectively,
and uses them to redistribute the lightness values of the image.
It is therefore suitable for improving the local contrast andenhancing the definitions of edges in each region of an image.
In experiment, we get images with a standard plate and fishing
net at the distance of 5 m by underwater range-gated laser
imaging system. Then we use the CLAHE and HE to enhance
the images, and evaluate the quality of enhanced images bypeak signal to noise ratio (PSNR) and image contrast. The resultshows that both the CLAHE and HE significantly enhances thebrightness and contrast of images, but the HE gets the images
over-enhanced, while the CLAHE has a good enhancement withcompressing the over-enhancement and the influence of ununiform light by the using of adaptive local enhancement, it also
has higher value of PSNR and contrast than HE. The experimental
results demonstrate that the CLAHE has a good result of image
enhancement for target detection by underwater range-gatedlaser imaging system.

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10020-44, Session Post

A novel representation and compression
method in layered depth video
Zefu Li, Ran Ma, Shanghai Univ. (China)
Layered depth video (LDV), as a sparse representation of multiview video plus depth (MVD), is considered as a promising 3D
video format for supporting 3D videos services. This format
consists of one full or central view and additional residual datathat represent side views needed to be transmitted. However,
the amount of residual data becomes larger when the distance
between the central view and side views increases. This occurs
when parts of the central view are not visible in the side views,
leaving some holes called disocclussions. To address thisproblem, in this paper, a new inpainting-based residual data
generation method is presented. The holes can be inpainted
by using the available texture inside the central view. Then, theinpainting-induced artifacts are considered as new residual
data and the residual data of two side views is merged into one
buffer to further reduce the amount of data. For better coding
efficiency, the block wise alignment is proposed to adapt to theblock structure in current high efficient video coding (HEVC)
coder firstly. Then in order to fit the shape or distribution ofresidual data, a proper code unit (CU) size and split pattern is
proposed. The experiments show high compression efficiencyof the proposed representation and compression method. The
proposed method allows reduction of required bitrate of atleast 30% comparing to classical LDV method, while they havethe similar quality of intermediate virtual view in the terminal’s
display.

10020-45, Session Post

Pedestrian detection based on redundant
wavelet transform
Lin Huang, Tie-Jun Yang, Li-ping Ji, Ping Hu, Guilin Univ. ofTechnology (China)
Intelligent video surveillance is to analysis video or image
sequences captured by a fixed or mobile surveillance camera,
including moving object detection, segmentation andrecognition. By using it, we can be notified immediately in an
abnormal situation. Pedestrian detection plays an importantrole in an intelligent video surveillance system, and it is also a
key technology in the field of intelligent vehicle. So pedestrian
detection has very vital significance in traffic management
optimization, security early warn and abnormal behavior
detection. Generally, pedestrian detection can be summarized
as: first to estimate the moving area; then to extract the featuresof region of interest; finally to classify samples using a classifier.
Redundant wavelet transform (RWT) overcomes the deficiencyof shift variant of discrete wavelet transform, and it has better
performance in motion estimation when compared to discrete
wavelet transform. Addressing the problem of the detection ofmulti-pedestrian with different speed, we present an algorithmof pedestrian detection based on motion estimation using RWT,
combining histogram of oriented gradients (HOG) and support
vector machine (SVM). Firstly, three degrees of movement(DoM) are estimated using RWT and the corresponding areas
are segmented. According to the different DoMs, a region
proposal (RP) is generated. Then, the features of a RP is
extracted using HOG. Finally, the features are fed into a SVM
trained by pedestrian databases and the detection results are
gained. Experiments show that the proposed algorithm estimatespedestrian with different speed more accurately than that ofsome state-of-art ones.

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV

10020-46, Session Post

10020-48, Session Post

High-resolution image restoration
algorithm of wavefront coding system
based on Lucy Richardson algorithm andwavelet denoising

Human body region enhancement method
based on Kinect infrared imaging
Lei Yang, Zhongyuan Univ. of Technology (China); Yubo
Fan, Xian Jiaotong Univ. (China); Xiaowei Song, WenjingCai, Zhongyuan Univ. of Technology (China)

Qiang Li, Feng Xu, Soochow Univ. (China)
Abstract:The middle blurred image is received by the detector
since the low modulation transfer function(MTF) of the
wavefront coding(WFC) imaging system. However, using anappropriate filter, the middle blurred image can be restoredwith enough target information saved because there is no zero
point in the passband of the MTF. While the signal has been
amplified by the filter in the restoration process, the noise of
the system is also enlarged and the signal to noise ratio(SNR)of the image is reduced. In order to solve the above issues, animproved algorithm has been proposed in the paper. The noise
is controlled by the wavelet in the reconstruction process, andthe middle blurred image is restored by the LR algorithm with aprior knowledge of the degradation function. Thus, the wavelet
denoising are combined with LR algorithm to restore the middle
blurred image of the WFC system. The test results show that thenoise of the reconstructed image has been suppressed and thepeak SNR and SNR has been improved, the restoration image
with the diffraction limit level has achieved good results in image
detail restoration and noise control.

10020-47, Session Post

Cross-center extraction with sub-pixel
accuracy
Guanghua Wu, Hefei Univ. of Technology (China) and
Academy of Opto-Electronics, CAS (China); Zili Zhang,
Weihu Zhou, Academy of Opto-Electronics, CAS (China)

10020-49, Session Post

In order to achieve automatic measurement function, laser
scanning measurement system need to ensure that measurement
system of the cross and the target center overlapped. To
develop the obtaining accuracy of the cross central coordinate,a novel algorithm based on the combination of two-step Hough
Transform and Sub-pixel curve fitting was presented. Firstly,
Hough Transform was used to detect the straight line of longaxis of the cross, and then the central coordinate value of thecross can be deduced roughly through straight line equations.
Secondly, take this coordinate as a center, and a certain numberof pixel values as the edge length, a region of interest (ROI)
can be defined. In this ROI, the two short axes of the crosswere obtained to detect the straight line roughly using Hough
Transform again. Then, the coordinate value of short axis was
acquired in pixel level with canny edge detection algorithm.
According to the equations of the straight line, rough errors were
removed through 3 rule, and the coordinate values of short axis
in sub-pixel level with curve fitting algorithm is obtained. Finally,
based on the sub-pixel level of coordinate values, straight line
equations of two short axes was presented with LSM, and thus
the coordinate of cross center would be accurately detected with
the intersection of two short axes. Experimental results showedthat the accuracy of the central coordinates value of crossapproaches to sub-pixel level and can satisfy the measurement
system requirements of high precision.

60

SPIE Photonics Asia·

To effectively improve the low contrast of human body region
in the infrared images, a combing enhancement method is
proposed to enhance the human body region. According to thecharacteristics of different kinds of noise in infrared images, acombing method with multiple enhancement methods is more
efficient than a single processing method. Firstly, for the infrared
images acquired by Kinect, in order to improve the overall
contrast, an Optimal Contrast-Tone Mapping (OCTM) methodwith multi-iterations is applied to balance the contrast of lowluminosity infrared images. Secondly, to enhance the humanbody region better, a Level Set algorithm is employed to improvethe contour edges of human body region. Finally, to further
improve the human body region in infrared images, a Laplacian
Pyramid decomposition is adopted to enhance the contourimproved human body region. Meanwhile, the background area
without human body region is processed by bilateral filtering to
improve the overall effect. The algorithm for human body region
enhancement is different from that for background processing,so the enhancement effect is better. With theoretical analysis
and experimental verification, the results show that the proposed
method could effectively enhance the human body region ofsuch infrared images. The proposed method shows an advantage
in the infrared image processing of human body area under nolight or dim light environment. It will help to recognize the humanbody region with clear human body shape and posture, and will
be helpful in the development of infrared surveillance system.

Binocular stereo matching method basedon structure tensor
Xiaowei song, Manyi yang, Zhongyuan Univ. of Technology(China); Yubo Fan, Xian Jiaotong Univ. (China); Lei Yang,
Zhongyuan Univ. of Technology (China)
A main research area of computer stereo vision is to recover the
3d coordinates of the object from multiple 2d images, and the
binocular vision technology based on two images is one of theresearch hotspots. In a binocular vision system, to recover the 3d
information of the object, the most important thing is to acquire
the matching points. In recent years, tensor theory develops
rapidly. Tensor has two characteristics. One is the transformation
rule of coordinate system, the other is multidimensionality.
Structure tensor shows better detection performance in thelocal structure region, and is very suitable to find the specificshapes like pedestrians, cars and road signs in images. In thispaper, the luminance information and the structure tensor are
combined to form the extended structure tensor. The directional
derivatives of luminance in x and y directions are calculated tohighlight the local structure of the image. The Euclidean distance
between feature vectors of key points is adopted as the similarity
judgment metric of the key points in the two images. The
coordinates of the matching points within the detected target in
the images are precisely acquired by matching. Experiments were
performed based on the left and right images of the captured
road signs. Binocular calibration was followed by image matchingfor matching points, and the target depth was calculated
according to the matching points. By comparison, it was provedthat the structure tensor could accurately acquire the matching
points in the binocular stereo matching.

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV

10020-50, Session Post

10020-52, Session Post

A vertical parallax reduction method forstereoscopic video based on adaptive
interpolation

Pure-optical broadband photoacoustic
detector based on total internal reflection

Qingyu Li, Yan Zhao, Jilin Univ. (China)
The existence of vertical parallax is the main factor of affecting
the viewing comfort of stereo video. Visual fatigue is gaining
widespread attention with the booming development of 3D orstereoscopic video technology. In order to reduce the verticalparallax without affecting the horizontal parallax, a self-adaptive
image scaling algorithm is proposed, which can use the edge
characteristics efficiently. In the meantime, Levenberg-Marquardt(L-M) algorithm which is the nonlinear algorithm, is introducedin this paper to improve the accuracy of the transformation
matrix. Firstly, the self-adaptive scaling algorithm is used to theoriginal image for interpolation. When the pixel point of original
image is in the edge region, the interpretation is implemented
adaptively along the edge direction obtained by Sobel operator.
Secondly the SIFT algorithm, which is invariant to scaling,rotation and affine transformation, is used to detect the feature
matching points from the binocular images. Then according to
the coordinate position of matching points, the transformation
matrix, which can reduce the vertical parallax, is calculated using
Levenberg-Marquardt algorithm. Finally, the transformation
matrix is applied to target image to calculate the new coordinate
position of each pixel from the view images. The experimental
results show that comparing with the method that reduces
the vertical parallax using linear algorithm to calculate twodimensional projective transformation, the proposed method
improves the vertical parallax reduction obviously, at the sametime, in terms of the impact on horizontal parallax, the proposed
method is more closer to the original image. Therefore, theproposed method can optimize the vertical parallax reduction.

10020-51, Session Post

Single face image reconstruction for superresolution using support vector regression
Haijie Lin, Qiping Yuan, Tianjin Univ. of Technology(China); Zhihong Chen, Xiaoping Yang, Tianjin Univ.
(China)In recent years, we have witnessed the prosperity of the face
image super-resolution (SR) reconstruction, especially thelearning-based technology. In this paper, a novel super-resolution
face reconstruction framework based on support vector
regression (SVR) about a single image is presented. Given some
input data, SVR can precisely predict output class labels. We
regard the SR problem as the estimation of pixel labels in its highresolution version. It’s effective to put local binary pattern (LBP)
codes and partial pixels into input vectors during training models
in our work, and models are learnt from a set of high and low
resolution face image. By optimizing vector pairs which are used
for learning model, the final reconstructed results were advanced.
Especially to deserve to be mentioned, we can get more highfrequency information by exploiting the cyclical scan actions in
the process of both training and prediction. A large number ofexperimental data and visual observation have shown that our
method outperforms bicubic interpolation and some state-ofthe-art super-resolution algorithms.

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Xiaoyi Zhu, Wenzhao Li, Changhui Li, Peking Univ. (China)
Photoacoustic tomography (PAT) uniquely combines the opticalabsorption contrast and ultrasonic detection, which is superior
for optical absorption detection. Over the past decade, PAT hasgained significant progresses in both technical development andbiomedical implementations. Due to the large scale difference intissue optical absorbers, Photoacoustic (PA) signals could cover a
very wide frequency range. Therefore, the photoacoustic detector
desires not only high sensitivity, but also wide bandwidth. Due tothe high detection sensitivity and the extreme wide bandwidth,
several pure optical detection detectors based on different
mechanisms have been studied, including the Mach-Zehnderinterferometer [1], Fabry-Perot Polymer [2], micro-ring resonator[3], low-coherence interferometer [4], and surface plasmon
resonance detector [5]. In this study, we proposed a new PA
detection method that based on total internal reflection (TIR).
The stength of the reflected light is modulated by the variationof media refractive index (RI) that caused by PA pressure waves.
Our method can extract extreme weak signals. Both phantom
and animal experimental results demonstrated this novel method
can provide a broadband and sensitive PA imaging.

10020-53, Session Post

Research on free-space opticalcommunication based on time-divisionmultiplexing
Dan Wang, Jinan Univ. (China); Wenchao Zhou,
The Second Compulsory Drug Rehabilitation Ctr. of
Guangdong Province (China); Zhen Li, Zhenqiang Chen,
Hao Yin, Siqi Zhu, Anming Li, Jinan Univ. (China)
Free-space optical (FSO) communication is a technology that
can transfer sound, image and text information using laser beam
as a data carrier. With the advantages of a huge resistance toelectromagnetic interference, a wide range of available spectrum,
ease of implementation and high data rate, FSO systems arewidely used in scientific research, military, civilian and otherfields. This paper reports an improved design for video and audio
synchronous wireless transmission system. Video and audio
signals are time division multiplexed and then are modulatedby an acousto-optic modulator (AOM). The modulated signal
propagates through the atmosphere and is received by thephotoelectric convertor. The original signal is recovered byde-multiplexer. Video signal is showed by a monitor and audio
signal is tested by a speaker. The 3dB bandwidth of this system is
6.7MHz. The system achieves the functions of signal multiplexing
and wireless transmitting with the help of a designed circuit andmicrocontroller programming. The time-division multiplexer/demultiplexer is provided by means of a microcontroller, switching
chip and other auxiliary circuit. The photoelectric convertor ispresented by making use of a photodiode and amplification
circuit. Proved by experiments, this system perfectly meets theactual requirements with advantages of flexibility, practicality
and low cost. And it provides an efficient scheme of synchronous
wireless transmission of video and audio signals for monitoring
system and TV access network.

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV

10020-54, Session Post

10020-56, Session Post

Sinogram-based adaptive iterative
reconstruction for sparse view x-ray
computed tomography

Automatic identification of various
spectral features at the time-resolved
excitation emission matrix of dissolved
organic matters and phytoplankton cells inseawaterDragos Trinca, Yang Zhong, Y. Z. Wang, Talgat
Mamyrbayev, Tomsk Polytechnic Univ. (RussianFederation); E. Libin, Tomsk State Univ. (RussianFederation)
With the availability of more powerful computing processors,
iterative reconstruction algorithms have recently beensuccessfully implemented as an approach to achieving significant
dose reduction in X-ray CT. There are two ways of reducing thedose, either by (1) reducing the scanner flux, or by (2) decreasing
the number of views. In this work, we propose an adaptive
iterative reconstruction algorithm for X-ray CT, that is shown toprovide results comparable to those obtained by proprietaryalgorithms, both in terms of dose reduction (using the second
approach for reducing the dose) and execution time. One of
the main advantages of the proposed algorithm, as comparedto other non-proprietary algorithms that have been proposed,is that it is not only fast at the reconstruction process, but also
fast at the scanning process, as it requires a significantly smaller
number of views.

10020-55, Session Post

Research of nonlinear simulation on sweep
voltage of streak tube imaging lidar
Qian Zhai, Shao-kun Han, Yu Zhai, Jie-yu Lei, Jian-feng
Yao, Beijing Institute of Technology (China)
When the streak tube imaging lidar is used to detecting andimaging the target, the range accuracy is influenced by thenonlinearity of the sweep voltage. In order to study the nonlinear
sweep voltage, a nonlinear distance model of streak tube is
proposed based on the principle of streak tube imaging lidar
system and streak image is obtained, the nonlinear influencesof the system are analyzed from multiple perspectives after
comparing the simulation results with the ideal results. Firstly,
the model of the parallel-plate deflection system is studied, andthe mathematical relation between the sweep voltage and theposition of the image point on the screen is obtained based on
the movement rule of phoelectron. Then, the mathematical modelof the sweep voltage is established on the basis of its principle
and the nonlinear distance model of the streak tube is obtained.
After that, the simulation of streak image is carried out for theselected staircase target, corresponding sweep voltage slope ofthe system can be calculated by the simulation result and therange image of the target can be reconstructed by extremum
method. Comparing reconstruction result and actual target, therange accuracy caused by the nonlinearity of the sweep voltage
is obtained.Under the principle of full screen sweeping, thecurve of the errors varying with target ranges is also obtained.
Finally,the influence of parameter relate to sweep time on therange accuracy of the system is analyzed. The results of research
provide theoretical reference for optimal parameter selection tominimum range error and it can provide effect prediction for thedesign of streak tube imaging lidar.

Pavel A. Salyuk, V.I. Il’ichev Pacific Oceanological
Institute (Russian Federation) and Far Eastern State Univ.
(Russian Federation); Vladimir Krikun, V.I. Il’ichev Pacific
Oceanological Institute (Russian Federation)
The variation of the different parameters of the exciting radiationand the registration of the fluorescence of the investigated object
allows to obtain multidimensional spectral images: from threedimensional (length of the exciting radiation, the wavelengthof the emitted radiation, the fluorescence intensity) to eightand more dimensions (in addition to three of these dimensions:spatial coordinates x, y, z; time of measurements; the durationand the intensity of the exciting radiation and etc.). In the case ofmeasurements in natural conditions is highly desirable that theresult of the processing performed during a single measurement
for the operation in real time.
In this paper we consider the approach described for thetreatment of fluorescence measurements of dissolved organic
matter and chlorophyll-a in seawater. Joint analysis of the various
pairs of wavelengths of excitation / emission fluorescence,
fluorescence analysis at different durations of the exciting
radiation and the time-spatial analysis of the received signal
allow identifying different types of fluorescent dissolved organic
matter and estimate their stage of biodegradation, to study thefunctional state of phytoplankton cells. So it is possible to provide
real-time investigation of environmental indicators of seawater.

10020-57, Session Post

The equipment for time-resolved
measurements of excitation-emission
matrix of seawater fluorescence in natural
conditions
Ivan G. Nagorny, Far Eastern State Univ. (RussianFederation) and Institute for Automation and Control
Processes (Russian Federation); Pavel A. Salyuk, Vladimir
A. Krikun, V.I. Il’ichev Pacific Oceanological Institute(Russian Federation); Alexander Yu Mayor, Konstantin A.
Shmirko, Institute for Automation and Control Processes(Russian Federation)
Excitation-emission matrix (EEM) technique is widely used in thelast decade to study the properties of organic matter in seawater.
Additional variations of the exciting radiation parameters (inaddition to the wavelength), such as the duration and intensity,
allow to get more spectral information about the object of
research, and allow to identify some individual components ofthe tested sample or to study the dynamics of the molecularchanges in the sample of analyzed liquid.
One of the main limitations of the EEM technique is thatusually necessary to carry out research in the laboratory on thespecialized equipment. In this paper describes the hardware
system that allows to carry out measurements in the field studies.
The hardware system includes a set of light-emitted diodes(LEDs) working in the range from 245 to 600 nm, which produce
sequential excitation fluorescence of the sample liquid, which isdetected using a 32-channel photomultiplier tube (PMT). Numberof LEDs can vary from 7 to 16. Through the use of multi-channel

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV
photomultiplier reached the required measurement sensitivity
and efficiency measurement is less than 1 minute for full cycle.
Some channels are set to ultra-variable fluorescencemeasurements of phytoplankton cells. Minimum 4 channel
in excitation range of 350-600 nm support the work ofvariable duration excitation pulses from a micro seconds toseconds. This makes it possible to measure the fluorescenceof the chlorophyll-a with closed or open reaction centers ofphytoplankton cells. The use of multiple excitation radiation inchannel allows to activate various mechanisms of energy transfer
in the photosynthetic apparatus of phytoplankton cells, improves
measurement accuracy, reduces dependence on the variation in
species composition and functional state of phytoplankton cells.

10020-21, Session 5

Development of an atmosphericturbulence simulator for deformablemirror evaluation (Invited Paper)
Jun Ho Lee, Sunmi Shin, Kongju National Univ. (Korea,
Republic of); Hyug-Gyo Rhee, Ho-Soon Yang, Korea
Research Institute of Standards and Science (Korea,
Republic of); Ho-Jae Lee, Korea Institute of Industrial
Technology (Korea, Republic of)Currently we are developing a 10cm silicon carbide (SiC)
deformable mirror with 37 actuators operating at 500 Hz. The
deformable mirror aims to be applied into a 1.5m telescope.
The adaptive optics system capability with the deformablemirror was simulated and predicted based on the Kolmogorov
atmospheric turbulence model. However, in order to confirm
the prediction, a closed-loop adaptive optics system wasconstructed with an insertion of an atmospheric turbulencesimulator. The atmospheric turbulence simulator consists of
two point sources, a Boston deformable mirror and double
random phase plates. In order to simulate a binary star, thetwo point sources are mounted on 3-axis micron meter stages,
respectively and are optically merged into a single beam pathby a beam splitter cube. Each light intensity of the source isadjustable to a corresponding stellar magnitude while the angularseparation is precisely adjusted by moving the 3-axis stages. The
atmospheric disturbance is generated by shaping the Boston
deformable mirror and also by rotating double phase plates. The
fried parameter of the generated the atmospheric disturbancecorresponds from 7cm to 15cm at 500nm at the telescope pupil
plane, which represents a typical seeing condition at Bohyun
observatory, South Korea. At the first, the Boston deformablemirror has 12 x 12 actuator array with 400 ?m pitch and actuator
control signals are generated based from the Kolmogorov
atmospheric model and frozen layer theorem. At the second, thephase plates are glass plates with some residual aberrations. The
rotating direction and velocity of each random phase plate iscontrolled to represent the atmospheric turbulence wind profiles.

10020-22, Session 5

Solutions to improve space-time adaptive
systems resolution
Hua Liu, Science and Technology on Electro-Optic Control
Lab. (China)
The principle approach, modeling, and error analysis areanalyzed, and the system configuration based on SLM isadvanced in algorithm analysis. For to improve the resolutionof the imaging system, and achieve the theoretical limit, we
introduced that the core methodology, which is that in the deep
understanding and research of the photoelectric information
control, the basic theory of the spatial light modulator and the

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algorithm based on space-time adaptive system is discussed
deeply which used to the core of the photoelectric system
configuration by which key components applied to solve thecontrol function. This paper discusses the hardware system.
Usually, an SLM modulates the intensity of the light beam.
However, it is also possible to produce devices that modulate
the phase of the beam or both the intensity and the phasesimultaneously. Adaptive configuration, for a complicate sensor isaccomplished by an implementation of structured programming,based on global optimization algorithm , which explores theavailable configuration space formed by powers of individualcomponents and inter-component separations. Besides, thediscuss includes the control on the SLM for spatial information of
the amplitude, phase, frequency, polarization, and the intensityof energy research. A typical model is used to illustrate thefeasibility, and the criteria is developed.The technology principleof super resolution restructure from the point of view on theory
and engineering. Three kinds of restructure technologies, that
prototype, micro scanning and sub pixel are described, andhow to decrease their shortcomings are discussed in detail.
Furthermore, to improve the band width by reconstruction
without the spectral alias in super resolution technologies, a newcoding technology combining a optical encoding and the sub
pixel is proposed. With the global method, simulation results
show that the system can meet the application requirements in
MTF, REA, RMS and other related criteria.Results show that they
are effective solutions.

10020-23, Session 5

Calculation of overlapping pixels for
optical-butting focal plane
Fuqiang Li, Junlei Chang, Bei Chu, Beijing Institute ofSpace Mechanics and Electricity (China)
The resolution and observing width of optical remote sensing
camera can be enhanced by increasing the detector length offocal plane. Optical butting is used to increase the imaging length
owing to its simple structure, low cost and the simultaneouslyimaging detectors. But butting process is influenced by manyfactors, which result in imaging gaps, so overlapping pixels
between adjacent detectors is the key. In this paper, the factors
causing imaging gap are analyzed, and calculation of overlapping
pixel number is given out based on the analysis. Firstly an opticalbutting focal plane system is built on optical imaging principles.
Then the factors causing imaging gap are listed and analyzed,
under the consideration of telecentric and non-telecentric
optical system. Based on the imaging gap analysis, a formula foroverlapping pixel number calculation is obtained, with the MTF
assurance in vignetting districts resulted from optical butting.
Finally a calculation example of a camera is given.

10020-24, Session 5

Enhancing the actual operational
performance of coaxial three-mirror
anastigmatic optical system by wavefront
codingZhang Binglong, Bin Hu, Jiangao Jin, Bo Li, Ningjuan
Ruan, Yun Su, Beijing Institute of Space Mechanics andElectricity (China)
Coaxial Three-Mirror Anastigmatic (TMA) optics has been wellknown in remote sensing for excellent anti-astigmatic, butspace environmental disturbances such as thermal field change,
vibration often caused optical elements to deformation, tilt or
position deviation, the degree of structure stability became thekey factor to influence the actual performance when coaxial TMA#PhotonicsAsia

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Conference 10020:
Optoelectronic Imaging and Multimedia Technology IV
run in orbit. This paper presented the pupil phase distribution
by which optical system became insensitive to defocus anddefocus-related aberrations, the corresponding phase mask
was designed and placed to pupil position of coaxial TMA,
optimized the modified optics in ZEMAX, a filter was developed
based on wiener filter, the filter could effectively restore the blur
produced by phase mask and defocus, but magnify the image
noise a little, finally, analyzed the actual performance of modified
imaging system by the simulation, and result showed that, byusing Wavefront Coding, the fabrication and assembly toleranceof coaxial TMA optical system could be relaxed to 2 times,
the depth of focus of system could be extended to 16 times
than before, and the imaging quality is almost invariant, actual
performance in orbit was enhanced dramatically.

10020-26, Session 5

Break diffraction limit using nearestneighbour pixel-modified optical transfer
function
Yu Wang, GDS Optics (United States)
For images taken by a diffraction limited optical system; if the
pixel pitch of the system’s detector is much smaller than thediffraction limit, then the spatial resolution of the images can beenhanced by a method called nearest neighbor pixel modified
optical transfer function. This method rewrites the point spreadfunction in terms of the nearest pixels, and then develops a
modified optical transfer function using the Shift Theory of
Fourier Transform. Theoretical simulation shows that this method
is able to enhance resolution of single frame images beyond
the diffraction limit. Initial experiment results were in good
agreement with the simulation. We have applied this method to
two of NASA’s space images, with many hidden details appearing
in the processed images.

10020-27, Session 6

Colour image encryption using affine
transform in fractional Hartley domain(Invited Paper)
Anil K. Yadav, Phool Singh, Kehar Singh, The Northcap
Univ. (India)
A novel scheme for colour image encryption using the fractional
Hartley and affine transforms is proposed. An input colour image
is first decomposed in its RGB (red, green and blue) components.
Each component is bonded with a random phase mask (RPM)
and then subjected to a fractional Hartley transform followed
by affine transform. Thereafter, a second random phase mask
is applied to each component before the final transformation
by inverse fractional Hartley transform resulting in componentwise encrypted image. Finally, the components are combined
to give a single channel colour encrypted image. The processof decryption is just the reverse of encryption. The scheme
is validated with numerical simulations performed on colour
image of Lena of size 256x256 pixels using MATLAB 7.14. The
use of affine transform along with fractional Hartley transform
adds to the security. The scheme is evaluated for its sensitivity
to parameters of the fractional Hartley and affine transforms.
It is found to be highly sensitive to encryption parameters by
analysing the plots of correlation coefficient (CC), mean-squarederror (MSE) and peak signal-to-noise ratio (PSNR). Also, it isevaluated for its robustness against the usual noise and occlusion
attacks. The proposed scheme is found to be secure and robust
owing to multiplicity of encryption parameters introduced
through the type of transform used.

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10020-28, Session 6

A multi-image super-resolution via hybrid
registration with depth information
Shi Lei, Tsinghua Univ. (China)
Multi-image super-resolution (MISR) reconstructs a highresolution image from a set of low-resolution images of the same
scene. Precise alignment of the input images is an essential partof MISR. However, it is a great challenge to align corresponding
images electively and efficiently. To address this problem, in thispaper we propose a novel hybrid method to precisely registera set of low-resolution images of different views employing
the corresponding depth information. Utilizing the geometricmapping relationship between depth and position in real world,
depth information is employed to find the corresponding
position in the reference image. A high-resolution image isthen reconstructed using cubic interpolation. Our algorithm iscompared to several multi-image super-resolution algorithms
using six groups of images from HCI database. Results andanalysis show that our method performs better than others
registration methods.

10020-30, Session 6

Experimental research on showing
automatic disappearance pen handwriting
based on spectral imaging technology
Yi Su, National Police University Of China (China); Lei Xu,
Yi Su, Institute of Forensic Science (China); Ningning Liu,
People’s Public Security University of China (China)
At present, more and more criminals utilize the automaticallydisappeared pen for economic fraud?so that investigators cannot
get a direct evidence of the disappearance of writing. However,
the existing technology has unsatisfactory effect in term ofcompletely disappeared handwriting. In this research, according
to the principle of imaging spectrometer, and combined with thedifference of absorption and reflection in various substances indifferent bands to identify the potential handwriting which left
on the surface of different papers, that provides a new method
for the inspection of disappeared handwriting. This paper adopt
the visible spectrum imaging technique to inspect disappeared
handwriting made by different disappeared pens in the same
object or by the same disappeared pen in different objects. Goodreveal effects could be obtained in both cases. Compared withthe video spectral comparator and sodium hydroxide solution
traditional methods, it is more simple, convenient, efficient andhas higher sensitivity. Meanwhile, as the optical nondestructive
testing, it can be used before the other methods, improving theinspection efficiency and offering important evidence for thedetection of the disappeared handwriting cases.

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Conference 10021: Optical Design and Testing VII
Wednesday - Thursday 12–13 October 2016
Part of Proceedings of SPIE Vol. 10021 Optical Design and Testing VII

10021-201,

Freeform optics opening up a bright
future for imaging instrumentation
Jannick P. Rolland, R.E. Hopkins Ctr. for Optical Design
and Engineering (United States) and NSF/IUCRC Ctr.
for Freeform Optics (United States) and The Institute of
Optics, Univ. of Rochester (United States)
Freeform surfaces in optical system design have alreadytransformed the lighting industry and have started to
revolutionize the imaging industry following recent advances thatempower innovation in optical instrumentation. In the context
of imaging, an historical highlight about freeform optics will befollowed with a discussion of key concepts and discoveries in
optical aberration theory that are currently guiding the designof freeform imaging systems for manufacturing with nanometerclass accuracy. Freeform manufacturing, enabled by maturing
techniques that include polishing, ion beam finishing, diamondmachining, milling, and magnetorheological finishing, will be
discussed. Building on simultaneous theoretical as well as rapid
technical advances across industries from design to assembly,
three design case studies will be discussed to highlight the
emerging benefits of freeform optics in imaging systems as wellas the design for manufacture process. With the emergence ofhigh definition displays and sensors, together with the constantquest for more compact and higher performance optical imaging
technologies across a wide range of applications, freeform optics
opens the path for a rich space of solutions that will enable thescience of tomorrow.

10021-202,

Innovative large wide-field astronomical
telescope: LAMOST
Xiangqun Cui, Nanjing Institute of Astronomical Optics& Technology (China) and National Astronomical
Observatory (China)
LAMOST, Large Sky Area Multi-Object Fiber Spectroscopic
Telescope, is one of the most innovative telescope configurationsin the world with the both wide field-of-view and the large
aperture, four-thousand optical fibers, and sixteen spectrographs
equipped. LAMOST has the capability to observe and capturetens of millions of spectra of celestial objects such as stellar,
galaxies, and quasars.

10021-1, Session 1

Efficient stimulated Raman scattering in
hybrid liquid-silica fibers for wavelength
conversion (Invited Paper)
Sylvie Lebrun, Lab. Charles Fabry, Institut d’Optique(France); Minh Châu Phan Huy, Philippe Delaye, Institutd’Optique Graduate School (France); Gilles Pauliat, Lab.
Charles Fabry, Institut d’Optique (France)
For nearly 10 years, we have developed a new kind of fiber
wavelength shifters based on Stimulated Raman Scattering in theliquid filling the hollow core of photonic crystal bandgap fibers
or Kagome fibers. The liquid choice, the design of the photonic
microstructure, the fiber length and diameter give us enoughdegrees of freedom to realize efficient and versatile shifters,
each being optimized for a specific wavelength shift. Connecting

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such a fiber device to a fixed wavelength laser allows deliveringa new wavelength. With the same laser, another wavelength
can be readily obtained by connecting another shifter. Using
various microlasers delivering 532 nm sub-nanosecond pulsesof about 1 ?J, we already built a full series of shifters to reachany wavelength among: 556 nm; 561 nm; 582 nm; 595 nm; 612
nm; 630 nm; 650 nm; 667 nm; 772 nm. Other wavelengths could
be reached by designing new shifters. In this presentation, we
will detail how we design and optimize these new devices toreach the targeted wavelength with high conversion efficiencies(up to 80% of the initial photons are converted at the desired
wavelength), narrow linewidths (typically less than 0.5 nm) andtransverse single mode operation.

10021-2, Session 1

Diffractive optical elements for multidimensional subdiffraction-limit spot
generation: design, demonstration, andcharacterization (Invited Paper)
Yusuke Ogura, Jun Tanida, Osaka Univ. (Japan)
We present diffractive optical elements (DOEs) for generating
wavelength-multiplexing and three-dimensional (multidimensional) arrays of subdiffraction spots, which are smaller
than the single diffraction limit spot. This method is based on
the use of propagating light, and its superior features, including
spatial parallelism and remote accessibility to matter, canbe utilized in applications. In design, special constraints are
introduced into the Gerchberg-Saxton algorithm to control thephases of spots and to disperse light energy to a surroundingarea. In each iteration, the phase distribution of a wavelengthmultiplexing DOE is synthesized from the phase distributions
obtained tentatively for the individual wavelengths. As an
example, a two-wavelength two-plane DOE was investigated.
The design result showed that expected spot arrays weregenerated for two wavelengths on the individual output planes.
We constructed an experimental system with a spatial light
modulator and demonstrated that the generated spot arrays werein conformity with the design result. Spot sizes were reduced toless than 80% of that of the diffraction limit spot. Characteristicsof this type of DOEs were also evaluated by numericalcalculation. For example, the result shows that the focal depth isextended in subdiffraction-limit spot generation. We believe that
this study contribute to expand application fields of DOEs.

10021-3, Session 1

The development of an adaptive optics
system and its application to the
biological microscope (Invited Paper)
Masayuki Hattori, Yosuke Tamada, National Institute for
Basic Biology (Japan)
The improvement of the optical devices in this decade, suchas the MEMS-SLM (Micro Electro Mechanical Systems-Spatial
Light Modulator) and wave front sensor with micro lens device,
is making adaptive optics commonly available. It also gives the
new basis of the design of adaptive optics with the improved
accuracy and the compactness. We have developed an adaptive
optics bench from such a point of view, and the application
to the optical microscope has attained effective results in theobservation of the live cell samples. In this presentation, ourrecent results will be shown. The result includes analysis of blurby the fine structures in biological sample and result of the image
correction by the adaptive optics.

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Conference 10021: Optical Design and Testing VII

10021-4, Session 1

Hybrid high-speed organic electro-optic
modulator
Feng Qiu, Kyushu Univ. (Japan)
Inside optical transmission systems, electro-optic (EO)
modulators are one of the vital building blocks. Among different
types of materials used to construct modulators, EO polymer
can offer intrinsic advantages such as a large EO coefficient(r33), high bandwidth, low dielectric constant and loss, andexcellent compatibility with other materials and substrates. Here,
we present several novel designed modulators based on the
EO polymer / titanium dioxide (TiO2) hybrid structure 1-2. They
includes: (1) vertical-stacked structure; (2) EO polymer covered
TiO2 nano-line; (3) Compact ring resonators; (4) EO polymer
filled slot waveguides. We give the design principle, describe thedevices’ fabrication process, and demonstrate the outstanding
optical properties of the fabricated devices.

10021-5, Session 1

In-depth performance analysis of anovel R-ORMS (remote optical rainfall
measurement sensor)[1] Ozolinsh M and Muizniece K (2015).Front. Psychol., 6:337[2] ARCTIC 39N FAMILY. http://www.varioptic.com/products/
variable-focus/arctic-39n/

Muhammad Hassan Bin Afzal, Primeasia Univ.
(Bangladesh)
A novel rainfall measuring sensor concept titled R-ORMS isbeing developed and proposed in this article. This specificsensor R-ORMS designed on the basis of tipping bucket rainfall
accumulation concept integrated with hydreon sensor’s highly
sensitive rain intensity measurement process. This article
systematically covered the comparative performance analysis
between following three rain gauges such as R-ORMS, tipping
bucket and hydreon sensor according to sensing principle,
resolution, rainfall measurement, and function of data counteror data logger and battery shelf life. It is clearly observed that,
R-ORMS performs much better compare to other techniqueswith better resilience. A comprehensive comparative study
been carried out to evaluate the durability and feasibility of
three techniques for rainfall measurement such as standard rain
gauges, proposed R-ORMS, tipping bucket based hydreon sensor.
These three methods are compared based on sensing principle,
resolution, rainfall measurement, and function of data counteror data logger and it’s battery shelf life. The R-ORMS designed
in such pattern that can overcome the common drawbacks ofall standard rain gauges. Some rain gauges are combined withwind speed detecting sensor, temperature detecting sensor
but R-ORMS purely designed to measure the total rainfall
by considering both accurate wind speed and temperaturedetection. This proposed sensing technology performs muchbetter than other available rain gauges by providing accurate
rainfall measurement.

10021-6, Session 1

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Aberration vignetting phenomena and its
visualization in wide angular objectives(Invited Paper)
Marina Letunovskaya, Irina L. Livshits, Igor S. Potemin,
Dmitry D. Zhdanov, Sergey Okishev, ITMO Univ. (RussianFederation); Heidi Ottevaere, Vrije Univ. Brussel (Belgium)
The term “vignetting” stands for a defect in which the brightnessof the image decreases toward the periphery compared to its
center.
There are different nature of vignetting, depending on which we
differ geometrical, mechanical and aberration.
Vignetting depends on the field angle and it is most important
for the wide angle objectives.
Aberration vignetting is produced by the pupil aberrations(mainly coma and distortion) and in some cases could be useful
to compensate the fall of relative illumination from center to theperiphery.
As a result of the action of different aberrations, aberration
vignetting could be both positive and negative. So it ispossible to compensate other types of vignettings and provide
uniform illumination along the image plane, this is hardware
compensation.

In spite that in modern devices the fall of relative illumination
could be corrected by software, hardware compensation isimportant as it provides real time action.

Maris Ozolinsh, Kristine Muizniece, Univ. of Latvia (Latvia);
Janis Berzinsh, “Barona Optika” (Latvia)
Chromostereopsis is a visual illusion whereby an impressionof depth is conveyed in two-dimensional color images.
Chromostereopsis can be sight and feel also in “Virtual Reality”
adapters, that induces the appearance of colour dependant

10021-7, Session 2

The requirement of obtaining uniform illumination in the image
plane is especially important for cartography both aerial andunderwater, lithography, and many other applications.

Chromostereopsis in “virtual reality”
adapters with electrically-tuneable liquidlens oculars

66

depth sense and, finally, combines this sense with the source
conceived depth scenarium. Previously we have investigatedhuman tolerance to induced chromostereopsis, that depends
on observer’s pupillary distance, age, near heterophoria andused correction type - typical binocular vision parameters[1].
Our studies are devoted to investigation the induced
chromastereopsis when using “Virtual Reality” adapters together
with mobile devices as smartphones. We did observationof composite visual stimuli presented on the high spatial
resolution screen of the mobile phone placed inside a portable“Virtual Reality” adapter. Separated for the left and right eyes
stimuli consisted of two areas: a) identical for both eyes color
chromostereopsis part, and b) additional conventional color
neutral random-dot stereopsis part with a stereodisparity basedon the horizontal shift of a random-dot segment in images
for the left and right eyes, correspondingly, and the observer
task was to equalize the depth sense for neutral and coloredstimuIi areas. Such scheme allows to determine actual observed
stereopsis disparity value versus eye stimuli color difference.
Additional to standard application in our adapter the tuneable“Varioptic” liquid lens oculars were incorporated additionally, thatallowed stimuli eye magnification, vergence and disparity values
control electrically[2]. At standard observation conditions foradapter with +2D ocular lenses for mobile blue-red stimuli , thechromostereopsis sensitivity was detected S?2.1[arcmin/(Labcolor difference)].

The article presents a method of physically accurate simulationof the light propagation in optical devices. Method is basedon stochastic ray tracing technics and can be applied to theimaging of three-dimensional objects under complex illumination
conditions. These solutions were used for the analysis andvisualization of the aberration vignetting effect. The article iswww.spie.org/pa·

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Conference 10021: Optical Design and Testing VII

illustrated with a number of visual examples of these phenomena
for different objectives like fish-eye lenses and eyepieces.

10021-8, Session 2

Single-pixel imaging by Hadamardtransform and ghost imaging and its
application for hyperspectral imaging(Invited Paper)
Yasuhiro Mizutani, Osaka Univ. (Japan); Kyuki Shibuya, The
Univ. of Tokushima (Japan); Hiroki Taguchi, Osaka Univ.
(Japan); Tetsuo Iwata, The Univ. of Tokushima (Japan);Yasuhiro Takaya, Osaka Univ. (Japan); Takeshi Yasui, The
Univ. of Tokushima (Japan)
In this paper, we report on comparisons of single-pixel imagings
using Hadamard Transform (HT) and the ghost imaging (GI) in
the view point of the visibility under weak light conditions. For
comparing the two methods, we have discussed about qualities
of images based on experimental results and numerical analysis.
To detect images by the TH method, we have illuminated the
Hadamard-pattern mask and calculated by orthogonal transform.
On the other hand, the GH method can detect images byilluminating random patterns and a correlation measurement.
For comparing two methods under weak light intensity, we
have controlled illuminated intensities of a DMD projector about
0.1 in signal-to-noise ratio. Though a process speed of the HT
image was faster then an image via the GI, the GI method has anadvantage of detection under weak light condition. An essential
difference between the HT and the GI method is discussed aboutreconstruction process. Finally, we also show a typical applicationof the single-pixel imaging such as hyperspectral images byusing dual-optical frequency combs. An optical setup consistsof two fiber lasers, spatial light modulated for generating patten
illumination, and a single pixel detector. We are successful todetect hyperspectrul images in a range from 1545 to 1555 nm at
0.01nm resolution.

10021-9, Session 2

See-through head-mounted display withgeometrical waveguide: a review (Invited
Paper)
Qichao Hou, Dewen Cheng, Yongtian Wang, Beijing
Institute of Technology (China)
See-through Head-mounted displays (HMDs) are widely usedin many field such as military, scientific research, assembly,
medical treatment, navigation and entertainment. In recent
years, researchers have introduced freeform optics, scanningtechnologies, holographic waveguide and geometricalwaveguide into the system of the see-through HMDs. Among
those technologies, the geometrical waveguide has tremendous
advantage to achieve high resolution, ultra-thin thickness, lightweight and full-color display. This talk reviews three types ofultra-thin geometrical waveguide applied in see-through HMDs.
In see-through HMDs, waveguide acts as a pupil expender, thewaveguide can be divided into two sections: input-coupling
structure and output-coupling structure. Input-coupling structure
is similar in different geometrical waveguide, whereas, outputcoupling structure varies much and directly determines theperformance of see-through HMDs. Three types of outputcoupling structures will be reviewed in this talk, partiallyreflective mirrors array, trapezoidal microstructures and triangularmicrostructures, separately. Each kind of waveguide has its
merits and demerits. The first type is easy to fabricate andcan achieves an FOV of 36o with a thickness less than 2 mm,

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whereas, the energy efficiency is relatively low; The second typehas a really high energy efficiency, but the inverted trapezoidal
microstructures are difficult to manufacture; The last typeimproves the manufacturability and has an acceptable energy
efficiency, but the mainly drawback is that a high refraction
material is needed which makes it expensive.
The working principle of each output-coupling structure will be
described in this paper, and then, we will give conclusions andrecommendations for future work.

10021-10, Session 2

A novel type of high-resolution dualchannel Kirkpatrick-Baez microscope
Qing Xie, Baozhong Mu, Yaran Li, Tongji Univ. (China)High resolution X-ray microscope is one of the essential
diagnostic methods for ICF physical experiments. In thecompressing phase, the target radiates wide brand X-ray during
several nanoseconds. Using the streak camera combined with
X-ray imager can measure time-resolved and high spatial
resolution details of the target’s ablation-front trajectory,
imploding velocity and nonuniformity in compressing process.
These diagnostic results will provide significant evidence tosupport the study about the energy absorption and inner surface
Rayleigh-Taylor instability theory of the target, which is important
for the target designing. It’s urgently necessary to provide
a microscopy system with high spatial resolution at several
micrometers and in a large view field with enough light gathering
power.
We designed a new type of X-ray microscope which can image
separately at 2.5 keV and 4.3 keV energy points with high spatial
resolution in large view field. This microscope is based on X-ray
Kirkpatrick-Baez optical structure. In the tangential direction,a bi-mirror reflective form is investigated to reduce off-axis
aberration and extend the view field with efficient resolution. In
the sagittal direction, a spherical mirror is zoning coated with
two kinds of multilayers to choose X-ray at different energy
points. Meanwhile, using reflective mirror has also a function of
focusing light to improve the gathering power effectively. The lab
experiments show that, the spatial resolution can achieve 5?m ata large view field of 600?m. This system, combined with a streak
camera, is also well applied in the implosion trajectory and RT
instability experiments.

10021-11, Session 3

The angular divergence control ofpartially-coherent beams using a phaseonly liquid spatial light modulator (Invited
Paper)
Xiaolong Ni, Changchun Univ. of Science and Technology(China)In order to reduce the complexity and cost of partially coherent
optical system, increase the convenience of partially coherent
laser beam application, in this paper, we presents a method tocontrol the coherence width and angular divergence of laser
beam complexly, using a phase-only liquid spatial light modulator.
First, the basic theory and method to control the coherence
width and angular divergence of laser beam using a liquid crystal
spatial light modulator are introduced; Then, the experiment totest the coherence width and angular divergence controlling
accuracy are carried out. The experiment results show that, fora partially coherent laser beam with the coherence width anddivergence angle are 0.9mm, 7.5mrad and 1.5mm, 3.8rad, theerror of coherence width is less than 5%, the root-mean-squareerror of the degree of coherence are 0.027386 and 0.031314,#PhotonicsAsia

67

Conference 10021: Optical Design and Testing VII

and the peak-to-valley are 0.084658 and 0.089103, the error ofdivergence angle is less than 10%, the root-mean-square errorof the degree of coherence are 0.032478 and 0.043186, andthe peak-to-valley are 0.091201 and 0.102130. This method cancontrol degree of coherence width and angular divergence with ahigh accuracy.

intensity of the transmitted beam, thereby enabling the detectionof the reversed domains. We also simulated the nonlinear effectusing a quadratic-soliton model, an associated fundamental
beam, and a SH beam interaction.

10021-12, Session 3

An integrated solution for compressionmolded glass lenses

Multi-tool design and analysis of an
automotive HUD (Invited Paper)

Bo Tao, Ye Yuan, Xinlin Zhou, Hua Chen, Wuhan Univ. of
Science and Technology (China)

Bruce R. Irving, Steve Mulder, David M. Hasenauer,
Synopsys, Inc. (United States)
Design and analysis of an optical system is often amultidisciplinary task, and can involve the use of specialized
software packages for imaging, mechanics, and illumination.
This paper will present a case study on the design and analysis
of a basic Heads Up Display (HUD) for automotive use. The
emphasis will be on the special requirements of such a visualsystem and on tools and techniques needed to accomplish thedesign. The first section will present an overview of the imaging
design using commercially available imaging design software.
Topics addressed include modeling the windshield, visualizing
the imaging performance, using constraints and free-form
surfaces to improve the system, and design/analysis methods formeeting specific visual performance specifications. The second
section will address the use of a CAD program to design a basic
mechanical structure to support and protect the optics. Thissection will also discuss some issues and limitations involvedin translating data between a CAD program and an opticalprogram. Typical issues that arise include the precision of opticalsurface prescriptions, surface and material properties, and the
management of large data files. In the final section, the combined
optical and mechanical package will be considered, using an
illumination design program for stray light analysis. This analysis
will be aimed at finding, visualizing and quantifying unexpected
ray paths. Techniques for sorting optical ray paths by path length,
power, and elements or materials encountered will be discussed,
along with methods for estimating the impact of stray light on
optical system performance.

10021-13, Session 3

Masaki Hisaka, Osaka Electro-Communication Univ.
(Japan)Optical processing using counter-propagating, pulse-shaped
spatial solitons to control the molecular structure deep inside
the optical material is investigated. A counter-propagating
femto-second Ti:sapphire pulsed laser focused at the surface ofa ferroelectric crystal such as a Ce-doped Sr0.75Ba0.25Nb2O6(SBN75) single crystal induces a pulse-shaped, second-harmonic(SH) spatial soliton beam associated with the self-focusing
fundamental laser. The counter-propagating SH beam collided
with the collision position deep inside the crystal, resulting in
the formation of a locally reversed crystal domain at the collision
point. This collision process can be controlled using external
threshold controls of electric field and crystal temperature. The
depth position can be controlled by an optical delay in one
optical path. Several domains at different axial positions can bereversed locally. The non-linear interaction between the soliton
collision and the approximate periodic reversed domain of arandom ferroelectric domain structure induces a change in the

SPIE Photonics Asia

In compression glass molding, residual stresses, refractive
index variation and geometric deviation are inevitable, and canaffect the optical performance of a molded glass lens, result in
substantial amount of aberrations. In order to achieve optimal
performance of molded glass lenses, residual stresses, refractive
index variation and geometric deviation have to be taken into
account simultaneously and be kept in a reasonable level. In
this research, an integrated procedure of modifying molds withannealing step was proposed to reduce geometric deviation,refractive index variation and residual stresses. Geometricdeviation predicted by the finite element method simulation
was used to provide feedback to modify the model geometry
design. Then, a post molding annealing step was followed.
Residual stresses and refractive index variation before and after
annealing step were measured. Residual stresses were measured
and reconstructed by using a circular polariscope. Refractive
index was measured and reconstructed by using an optical setup
based on Mach-Zehnder interferometer. Measurement results
confirmed that this post molding step is beneficial for lensdesign. The residual stresses and refractive index variation werereduced and controlled. This study demonstrated a suggestion
for compression glass lens to achieve better performance while
maintaining low cost.

10021-15, Session 3

Two-dimensional analytical modeling ofa linear variable filter for spectral ordersortingCheng-Hao Ko, Yueh-Hsun Wu, Symphony Chakraborty,
Sheng-Yu Tsai, Chi-Tsung Hong, National Taiwan Univ. of
Science and Technology (Taiwan); Bang-Ji Wang, JihRun Tsai, Chiu-Der Hsiao, National Space Organization(Taiwan)Optical processing deep inside opticalmaterials using counter-propagating
pulse-shaped spatial solitons (Invited
Paper)

68

10021-14, Session 3·

A two dimensional thin film thickness model based on thegeometry of the commercial coater which can calculate more
effectively the profiles of LVFs has been developed by isolating
the substrate plane as an independent coordinate (called local
coordinate) from the geometrical coordinate (called global
coordinate) whereas the rotation and translation matrix areused to establish the coordinate transformation between local
coordinate and global coordinate and combine the characteristic
vector with the step function to build a borderline on the surfaceof substrate in the local coordinate which can conclude that the
local mask will block the deposition or not.
The height of the local mask has been increased from 1mm up to
40mm in the proposed model and two dimensional simulations
are developed to obtain a thin film profile deposition on thesubstrate inside the evaporation chamber of the commercial
coater to achieve the specific request of producing LVF zone
width in a economical way than the previously reported.

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Conference 10021: Optical Design and Testing VII

10021-16, Session 3

Application of Q-type aspheric surface
in the design of Wynne-Dyson projection
lensCheng-Fang Ho, Wei-Jei Peng, Wei-Yao Hsu, Instrument
Technology Research Ctr. (Taiwan)
ITRC dedicates in high precision optics for more than 40
years and focuses in lithography optics for projection system
recently. The first project of the lithography optics in ITRC isan i-line Wynne-Dyson projection lens for 3D-ICs applications.
The Wynne-Dyson projection lens is a classical design for unity
magnification projection system. We take the advantages of theestablished benefits of Wynne-Dyson lens and modify it. ITRC‘s
Dyson lens is a 0.16 NA system with unity magnification, which isdesigned in double telecentricity and long working distance. The
projection lens comprises three lenses and one concave mirror.
Two aspheric surfaces are deployed in lens 1 and concave mirror.
A lens with aspheric surfaces can correct for aberration anddeliver a higher performance with fewer lens elements, therefore
it has advantages of compact and light. However, aspheres are
more difficult to fabricate and higher cost than spherical surface.
In order to control the testability and manufacturability of theaspheric surface, the Q-type aspheric surfaces are applied inour design phase and manufacture process. We optimize forboth performance and manufacturability by Q-type asphericsurfaces. Not only a testable and manufacturable asphere canbe approached but also an additional benefits of less sensitiveand cost-effective to manufacture to the required specification.
In this paper, the Q-type aspheric surfaces and slope constraint
are applied to a Wynne-Dyson projection lens, and then it iscompared to a design using standard power series asphericsurfaces. We estimate and compare the testability of bothtype aspheric surfaces by the departure from best-fit-sphereand fringe density of interferometry. Furthermore, subaperture
stitching interferometer system (ASI, from QED technologies)is also applied for testability comparison. The tolerance andsensitivity are also discussed. Finally, the results show adiffraction limit approached lens with testable aspheric surface
is designed using Q-type aspheric surface. One of the asphere is
150 um departure from best-fit-sphere in 226 mm clear aperture,that can be tested by subaperture stitching interferometersystem (ASI). The alignment tolerance of lens in decenter and tilt
can be controlled in the range of ±30 micron and 20 arc-second,
respectively.

10021-17, Session 4

Direct design of laser-beam shapers,
zoom-beam expanders, and combinations
thereof (Invited Paper)
Fabian Duerr, Hugo Thienpont, Vrije Univ. Brussel(Belgium)
Laser sources have become indispensable for industrial materials
processing applications like surface treatment, cutting or
welding; but also for medical applications like corneal surgery toname a few examples. Many of these applications pose different
requirements on the delivered laser irradiance distribution. Someapplications might not only favor a specific irradiance distribution(e.g. a flat-top) but can additionally benefit from time-varying
distributions.
We present an overview of a recently developed design
approach that allows direct calculation of virtually any refractive
or reflective laser beam shaping system. The derived analytic
solution is fully described by few initial parameters and does
allow an increasingly accurate calculation of all optical surfaces.
Unlike other existing direct design methods for laser beam

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shaping, there is almost no limitation in the number of surfacesthat can be calculated with this new approach. This is ofparticular importance for optical designs of dynamic systems
such as variable optical beam expanders that require four (ormore) optical surfaces. Besides conventional static beam shapers,
we present direct designs of zoom beam expanders, and as anovelty, a class of dynamic systems that shape and expand the
input beam simultaneously. Such dynamic zoom beam shapers
consist of a minimal number of optical elements and provide
a much more compact solution, yet achieving excellent overall
optical performance throughout the full range of zoom positions.
All presented ray tracing results confirm the high accuracy ofthe derived solutions and highlight the potential of this design
approach for various beam shaping applications.

10021-18, Session 4

Design of aspheric multifocal contact lens
using spline curve (Invited Paper)
Lien T. Vu, National Taiwan Univ. of Science andTechnology (Taiwan)
This paper presents a solution for the design of asphericmultifocal contact. The aspheric multifocal contact lenses consistof a zonal aspheric surface to increase add power values andreduce dependence on pupil diameter. However, the refractive
power distribution is continuous over a selected range but notsmooth, the visual acuity is still limited. In this research, themulti-aspheric curve on the optical surface profile of the asphericmultifocal contact lens is replaced by a single freeform spline
curve. A cubic spline curve is optimized to obtain the smoothconnection of the different vision correction zones and still satisfy
the power distribution of the aspheric multifocal contact lens.
The result shows that the contact lens using a cubic spline curve
could provide not only a smooth lens surface profile but also asmooth power distribution. This method can be extended to thedesign of multifocal contact lens with complex requirementsof the power distribution. The proposed contact lens is easilytransferred to CAD format for analysis or manufacture. Resultsof this study can be further applied for progressive contact lensdesign.

10021-19, Session 4

Design and verification of a flat-field
aberration-corrected concave blaze
grating for hyperspectral imaging
Cheng-Hao Ko, Sheng-Yu Tsai, Yueh-Hsun Wu, Chi-Tsung
Hong, National Taiwan Univ. of Science and Technology(Taiwan); Jih-Run Tsai, Bang-Ji Wang, Chiu-Der Hsiao,
National Space Organization (Taiwan)
A flat-field aberration corrected concave blaze grating for 4001100nm is designed and fabricated. An optical system is setup tomeasure the focused spot size, spectral resolution and diffraction
efficiency to evaluate the performance of aberration-correctedconcave grating. The blaze grating reaches a diffraction efficiencyof 70%. For an input point source at z = 0, the focused verticalspot size is 50µm, which indicates a 50µm spatial resolution at
the image plane. The focused horizontal spot size is 300µm,
which converts to a spectral resolution of 6nm. The design
methodology can be applied to an Offner type hyperspectral
imager with a free-form convex grating and variable line spacing
to achieve high efficiency and high spatial and high spectral
resolving power.

#PhotonicsAsia

69

Conference 10021: Optical Design and Testing VII

10021-20, Session 410021-31, Session Post

Aspheric and freeform surfaces testwith non-null subaperture stitchinginterferometry

Spatial distribution of current density andthermal resistance of high-power AlInGaN“vertical” and “face-up” light-emitting
diodesDong Liu, Lei Zhang, Yongying Yang, Tu Shi, Jian Bai,
Yibing Shen, Zhejiang Univ. (China)
A non-null subaperture stitching interferometry (NSSI) is
proposed for steep aspheric and free form surfaces testing.
A partial null lens (PNL) is employed as an alternative tothe transmission sphere, to generate different aspherical
wavefronts as references. In NSSI, aspheric surfaces are tested
with annular subapertures while free form surfaces withirregular ones. For aspheric surfaces in NSSI, the coveragesubaperture number would thus be reduced greatly for the
better performance of aspherical wavefronts in matching the
local slope of aspheric surfaces. For free form surfaces, irregularsubapertures are employed to reduce subaperture number andtake full advantage of resolution of interferometer due to thesurface asymmetry. A multi-subaperture simultaneous reverse
optimizing reconstruction (MSROR) method based on systemmodeling and ray tracing is proposed for full aperture figure
error reconstruction, instead of various mathematical stitchingalgorithms. All the subaperture measurements are simulated
simultaneously with a multi-configuration model in a raytracing program, including the interferometric system modelingand subaperture misalignments modeling. With the multiconfiguration model, full aperture figure error would be extracted
in form of Zernike polynomials from subapertures wavefront databy the MSROR method. This method concurrently accomplishes
subaperture retrace error and misalignment correction, requiring
neither complex mathematical algorithms nor subaperture
overlaps. A numerical simulation exhibits the performance of
the NSSI, which demonstrates its high accuracy in testing steep
aspheric and free form surfaces. Test results of an aspheric in
NSSI are shown to be in good agreement with those of Zygo
Verifire Asphere interferometer while results of a bi-conic surface
in NSSI are identical with those of Taylor Hobson contourgraph.

10021-21, Session 4

Design of freeform unobscured reflective
imaging systems using CI method
Tong Yang, Tsinghua Univ. (China); Wei Hou, Tsinghua
University (China); Xiaofei Wu, Guofan Jin, Jun Zhu,
Tsinghua Univ. (China)

SPIE Photonics Asia

Despite the continuous improvement of luminous efficiency ofmodern light-emitting diodes (LED), especially based on AlInGaN
quantum-wells system, self-heating and heat dissipation remain
important and often critical for the proper functioning of suchdevices. This paper presents a comprehensive analysis of theelectroluminescence (EL) and current distributions in connection
with thermal resistance in high-power “vertical” and “face-up”
AlInGaN light emitting diodes. The study was carried out using
a combination of high-resolution EL mapping techniques giving
information on the lateral distributions of near-field light emission
intensity and thermal transient measurements for evaluation ofthermal resistance of LEDs and its elements. It was shown thatthe “vertical” LEDs with the upper n-contact and a relatively thickn-GaN contact layer maintain better uniformity of the current
distribution up to currents greater than 1A, and accordingly havebetter energy efficiency (conversion efficiency and output opticalpower). Also, more uniform current distribution and the resulting
absence of significant thermal gradients improve reliability
and prolong service life. A good correlation was establishedbetween the current distribution and thermal resistance of LEDs.
Localization of current near the contact pads at high current
levels results in the increase of thermal resistance because of
the reduced cross section for heat flow from the active region
to the radiator. The slope of current vs. thermal resistance curveat the transition region from small to large currents can beused to estimate the dependence of LED’s efficiency and thenonuniformity of the current density and temperature distribution
on current and temperature.

10021-32, Session Post

In this paper, we demonstrated the design method of freeform
unobscured reflective imaging systems using the point-by-point
Construction-Iteration (CI) method. Compared with other pointby-point design methods, the light rays of multiple fields anddifferent pupil coordinates are employed in the design. The whole
design process starts from a simple initial system consistingof decentered and tilted planes. In the preliminary surfacesconstruction stage, the coordinates as well as the surface
normals of the feature data points on the freeform surface canbe calculated point-by-point directly based on the given objectimage relationships. Then, the freeform surfaces are generated
through a novel surface fitting method considering both thecoordinates and surface normals of the data points. Next, an
iterative process is employed to significantly improve the image
quality. In this way, an unobscured design with freeform surfaces
can be obtained directly, and it can be taken as a good starting
point for further optimization. The benefit and feasibility of thisdesign method is demonstrated by several design examples ofhigh-performance freeform unobscured imaging systems. All
these systems have modulation-transfer-function (MTF) curves
which are closed to the diffraction-limit.

70

Andrei V. Aladov, Submicron Heterostructures for
Microelectronics, Research and Engineering Ctr., RAS(Russian Federation); Vladimir D. Kuptsov, SaintPetersburg State Polytechnical Univ. (Russian Federation);
Anton E. Chernyakov, Aleksandr L. Zakgeim, Submicron
Heterostructures for Microelectronics, Research andEngineering Ctr., RAS (Russian Federation); Vladimir P.
Valyukhov, Saint-Petersburg State Polytechnical Univ.
(Russian Federation)·

Single camera stereo vision recognization
method for Parts’ pose on CMM
Fengshan Huang, Yamin Qin, Hebei Univ. of Science andTechnology (China)
Objective: In order to recognize parts’ pose on Coordinate
Measuring Machine (CMM) correctly and fast, a single camera
stereo vision recognization method based on the translationof (CMM) is proposed, and its principle, the pose parameterssolution and recognization procedure are studied. Method :According to the double cameras stereo vision principle, aimage of the part to be measured is captured by the CCD
camera, which is driven by CMM along the its X or Y axis, on
two different position correspondingly. Thus, the part’s single
camera stereo vision measurement is realized with the proposed
matching method on two images of the same feature point to bemeasured on the part, and each feature point’s 3D coordinatesin the camera coordinate system can be obtained. Then, using
the camera calibration parameters, each feature point’s 3D
coordinates in the machine coordinate system can be calculated.
At last, combining with each feature point’s 3D coordinates inwww.spie.org/pa·

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Conference 10021: Optical Design and Testing VII

the part CAD coordinate system, the part’s pose parameters canbe solved. Result&Conclusion:The recognization system is set
up, and the experiment is conducted?Experiment result showsthat the recognization method discussed above is correct andpractical, and the recognization time of is 1.818s which meets thereal-time measuring requirement .

10021-33, Session Post

Study on the characteristics of a novel
optical phased array based on waveguide
JiaYu Ye, Lijing Li, Wen Chen, BeiHang Univ. Institute of
Optics and Electronics (China)
A novel scheme of optical phasea array(OPA) based on waveguide is represented in this paper. Fiber paths is main design ofsystem, the single mode fibers are used as transmission paths,
photonic crystal fibers(PCF) are adopted as the output array,
LiNbO3 wave-guide is used as the phase modulator. The system
configuration have been given in the paper, performance ofmain device such as LiNbO3 wave-guide and PCF array are
analyzed. According to the theory of OPA and electro-opticaleffect of LiNbO3 wave-guide, the feasibility of system havebeen demonstrated.By adjusting the phase shift of each LiNbO3
wave-guide, the beam deflection have been observed. Simulation
experiments have been implemented to study the influence of
its structure parameter on output diffraction characteristics.
The results show that the inter-elements distance, the quantityof fiber core and arrangement of fiber core affect the beamscanning quality including full width at half-maximum(FWHM),
output intensity distribution and normalized amplitude
distribution. The grating lobes can be suppressed by smaller
distance, the beam scanning accuracy is improved by more unitsof fiber core. Then two-dimension arrangements of fiber core isanalyzed. By adjusting the arrangements of the fiber core, thecoupling coefficient and the coupling length between two fibercore in the PCF array are changed, which conduct the different
output amplitude distribution. So the structure parameter of PCF
array is main factor to the beam steering. With the developmentof craft for PCF, the research result will provide assistance for thedesign of OPA in the future.

Improved algorithm of ray tracing in ICF
cryogenic targets
Rui Zhang, Yongying Yang, Tong Ling, Zhejiang Univ.
(China); Jiabin Jiang, Zhejiang Univ. (China)
The high precision ray tracing inside inertial confinement
fusion (ICF) cryogenic targets plays an important role in thereconstruction of the three-dimensional density distribution
by algebraic reconstruction technique (ART) algorithm. The
traditional Runge-Kutta methods, which is restricted by theprecision of the grid division and the step size of ray tracing,
cannot make an accurate calculation in the case of refractive
index saltation. In this paper, we propose an improved algorithmof ray tracing based on the Runge-Kutta methods and Snell’s lawof refraction to achieve high tracing precision. On the boundaryof refractive index, we apply Snell’s law of refraction and contact
point search algorithm to ensure accuracy of the simulation.
Inside the cryogenic target, the combination of the Runge-Kutta
methods and self-adaptive step algorithm are employed forcomputation. The original refractive index data, which is used tomesh the target, can be obtained by experimental measurement
or priori refractive index distribution function. A finite differential
method is performed to calculate the refractive index gradientof grid nodes, and the distance weighted average interpolation
methods is utilized to obtain refractive index and gradient ofeach point in space. In the simulation, we take ideal ICF target,
Luneberg lens and Graded index rod as simulation model tocalculate the spot diagram and wavefront map. Compared thesimulation results to Zemax, it manifests that the improved
algorithm of ray tracing based on the fourth-order Runge-Kutta
methods and Snell’s law of refraction exhibits high accuracy.
The relative error of the spot diagram is 0.2%, and the peak-tovalley (PV) error and the root-mean-square (RMS) error of the
wavefront map is less than ?/35 and ?/100, correspondingly.

10021-36, Session Post

An improved NAS-RIF algorithm for image
restoration
Weizhe Gao, Xi Zhao, Jianhua Zou, Xi’an Jiaotong Univ.
(China); Rong Xu, Xi’an Satellite Control Ctr. (China)

10021-34, Session Post

Stray light analysis on helicopter opticallanding guidance system
Li Yangyang, YiFan Huang, Li LIn, Beijing Institute ofTechnology (China)
Shipboard helicopter optical landing guidance system can ensure
the safety of landing when the helicopter completed missions.
Stray light has a great influence on positional accuracy of the
optical landing guidance system. In order to improve the imaging
quality of the optical system, the sources of stray light in opticallanding guidance system were studied in this paper. Moreover, theeffects of stray light on the system were analyzed in detail.The
model of the optical landing guidance system was established in
the TracePro software, 16 different off-axis angles were selected
to carry out the ray tracing. Through modeling and simulation,
the irradiance of stray light in the imaging plane and the point
source transmittance (PST) of the system were obtained, they
were used to evaluate the level of stray light. Results show that
PST of the optical landing guidance system can achieve a level of
10-5~10-8 when the off-axis angle is equal to or greater than 50°.
At the same time, the solar stray light energy that gets to image
plane can achieve a level of 10-4W/m2. So the optical landing
guidance system can work regularly in this range.

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10021-35, Session Post

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Space optical images are inevitably degraded by atmosphericturbulence, error of the optical system and motion. In order to
get the true image, a novel nonnegativity and support constants
recursive inverse filtering (NAS-RIF) algorithm is proposed torestore the degraded image. Firstly?the image noise is weaken
by Contourlet denoising algorithm. Secondly, the reliable object
support region estimation was used to accelerate the algorithm
convergence. We introduce the optimal threshold segmentation
technology to improve the object support region. Finally, anobject construction limit and the logarithm function were added
to enhance algorithm stability. Experimental results demonstrate
that, the proposed algorithm can increase the PSNR of therestored images, improve the quality of the restored images. The
convergence speed of the proposed algorithm is faster than thatof the original NAS-RIF algorithm.

10021-37, Session Post

Optimization technique of wavefront
coding system based on ZEMAX
externally-compiled programs
Libo Han, Yuejin Zhao, Liquan Dong, Ming Liu, Xiaohua
Liu, Beijing Institute of Technology (China)#PhotonicsAsia

71

Conference 10021: Optical Design and Testing VII

Wavefront coding technique as a means of athermalization
applied to infrared imaging system, the design of phase plate is
the key to system performance. This paper apply the externallycompiled programs of ZEMAX to the optimization of phasemask in the normal optical design process, namely defining theevaluation function of wavefront coding system based on theconsistency of modulation transfer function (MTF) and improving
the speed of optimization by means of the introduction of
the mathematical software. User write an external program
which computes the evaluation function on account of thepowerful computing feature of the mathematical softwarein order to find the optimal parameters of phase mask, andaccelerate convergence through generic algorithm(GA), then use
dynamic data exchange (DDE) interface between ZEMAX andmathematical software to realize high-speed data exchanging.
The optimization of the rotational symmetric phase mask andthe cubic phase mask have been completed by this method, thedepth of focus increases nearly 3 times by inserting the rotational
symmetric phase mask, while the other system with cubic phasemask can be increased to 10 times. The maximum operating
temperature of optimized system range between -40?-60? andthe consistency of MTF is better within this range. Results showthat this optimization method can be more convenient to definesome unconventional optimization goals and fleetly to optimize
optical system with special properties due to its externallycompiled function and DDE, there will be greater significance forthe optimization of unconventional optical system.

10021-38, Session Post

Research on characteristic of radiometric
imaging quality for space-borne camera
with super-wide field of view

10021-39, Session Post

Multifocal intraocular lens to correct
presbyopia
Lai Jiang, Yongji Liu, Xiaolin Wang, Nankai Univ. (China);
Zhaoqi Wang, Nankai University (China)
Due to the loss of the flexibility of the crystalline lens, presbyopia
is the most common vision dysfunction for adults after 40. To
correct presbyopia, this paper presents a design of a multifocal
intraocular lens(MIOL), which can give extended clear vision
range both in photopic vision(3mm pupil diameter) and in themesopic vision(4.5mm pupil diameter). With a pseudophakic
eye model, a multi-configuration with object distance covering afull range for normal visual task from 8m to 0.4m were applied.
The surfaces of MIOL are aspherical diffractive surface. MIOL was
divided into two regions: the inner zone was optimized when the
pupil diameter was 3mm and the outer zone was optimized when
the pupil diameter was 4.5mm. Finally, we got a 22 diopters(D)MIOLwith a central thickness of 0.652mm and an optical diameterof 4.5mm. By evaluating the modulation transfer function, we
got optical performance of the pseudophakic eye with thisMIOL. When the pupil diameter of pseudophakic eye was 3mm,
MTF at 50c/mm and 100c/mm were above 0.4 and 0.15 for theobject distance from 8m to 0.4m. When the pupil diameter ofpseudophakic eye was 4.5mm, MTF at 50c/mm and 100c/mm
were above 0.25 and 0.09 for the object distance from 8m to
0.4m.The visual acuity was above 0.9 for the whole visual range
at both two pupil diameters. Therefore it is safe to say that the
new MIOL design provides good optical performance for wholevisual range under both the photopic vision and the mesopic
vision.

10021-41, Session Post

Huan Yin, Aerospace DongFangHong Satellite Co.,
Ltd. (China) and Anhui Institute of Optics and Fine
Mechanics (China) and Univ. of Science and Technology
of China (China); Qingshan Xu, Xiaoqing Wu, Anhui
Institute of Optics and Fine Mechanics (China); Lin Zhu,
Anhui Institute of Optics and Fine Mechanics, Chinese
Academy of Sciences (China) and University of Scienceand Technology of China (China); Bai Zhaoguang, Zhu
Jun, Lu Chunling, Di Guodong, Wu Bin, Aerospace
DongFangHong Satellite Co., Ltd. (China)

Simulation of the BSDF measurement
capabilities for various materials with
GCMS-4 gonio-spectrophotometer

In order to ensure the radiometic imaging quality for the spaceborne camera with super-wide field of view, we put forward a
new method, with which the apparent spectral radiance for any
field of view can be precisely calculated. Firstly, building theimaging model for the space borne camera, and the parametersof the orbits and attitudes of satellite, the line of sight for the
given field of view, the characteristics of different ground objects,
the state of the atmosphere, et al.. Secondly, calculating thegeometrical observation parameters for the given line of sightof the space borne camera. Finally, using the radiative transfer
model to calculate the value of the apparent spectral radiance.
Then, we use this method to calculate the apparent spectral
radiance for the space borne camera with the FOV of 75°basedon freeform mirror on a small remote sensing satellite. And
the results shows that the difference of the apparent spectral
radiance between the center of the FOV and the edge of the FOV
can be 26.9% at the reference of the apparent spectral radiancefor the central image pixel, when the satellite takes the imagingof the area of North Atlantic. And we should greatly consider thecharacteristic of the radiometric imaging quality for the spaceborne camera with super-wide field of view.

Dmitry D. Zhdanov, Igor S. Potemin, ITMO Univ. (RussianFederation); Vadim G. Sokolov, M. V. Keldysh Instituteof Applied Mathematics (Russian Federation); Alexey
A. Garbul, S.I. Vavilov State Optical Institute (RussianFederation); Alexey G. Voloboy, Vladimir A. Galaktionov,
M. V. Keldysh Institute of Applied Mathematics (RussianFederation)
For the physically accurate lighting simulation of various typesof objects it is necessary to consider the optical properties ofthese objects, which are usually defined by means of measuring
the Bi-directional Scattering Distribution Function (BSDF) using
gonio-spectrophotometer.
However the simulation results (image rendering or lighting
calculations) are to a certain extent differed from those actuallyobserved picture or photometric measurement result. One of
the main reasons for this discrepancy is the inaccuracy of BSDF
measurements for particular sample. The magnitude of error
depends on both the characteristics of gonio-spectrophotometerused for measurement and the combination of optical propertiesof the sample surface and material. In particular, in case of
BSDF measurements for the mirror like sample, the error will be
determined mainly by the angular size of detector, which hasa finite size, unlike infinitesimal angle of specular reflection. In
case of the sample with volume scattering material, some part of
scattered light misses the detector and thus not included in themeasurement results.
In this paper, the authors analyzed the accuracy of BSDF shapemeasured for later use of measurements in special software
for photorealistic visualization and virtual prototyping. Visual

72

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Conference 10021: Optical Design and Testing VII

and numerical analysis were done. In the first case we look at
the sample image rendered under specified lighting conditions,replacing its properties on the measurement results andvisually estimate the similarity (or difference). In the secondcase we compare the results of simulation of spatial or angularradiance distribution with results of corresponding radiometricmeasurements.

10021-42, Session Post

Image amplification-based superresolution reconstruction procedure
designed for wavefront-coded imaging
systemZhao Hui, Xi’an Institute of Optics and Precision
Mechanics, CAS (China); Caihui Zong, Univ. of Chinese
Academy of Sciences (China) and Xi’an Institute of
Optics and Precision Mechanics, CAS (China); Jingxuan
Wei, Xidian Univ. (China); Xiaopeng Xie, Xi’an Institute of
Optics and Precision Mechanics, CAS (China) and Univ. ofChinese Academy of Sciences (China)
Wave-front coding, proposed by Dowski and Cathey in 1995, is a
widely known powerful technique which is capable of extending
the depth of focus (DOF) of incoherent imaging systems. Since
then, many studies have been conducted but the possibility ofusing wave-front coding to obtain super-resolution has rarely
been investigated. By adding a suitably designed phase mask
to the aperture plane, the point spread function (PSF) becomesalmost invariant regardless of the defocus value.
Compared to the PSF of conventional imaging systems, the PSF
corresponding to wave-front coded imaging systems has a muchwider effective width. However, benefiting from its very large
PSF generated by the suitably designed phase mask, wave-front
coding could also be used to achieve super-resolution without
replacing the current sensor with one of smaller pitch size which
has many limitations for digital imaging systems.
In this paper, an image amplification based super-resolution
reconstruction procedure has been specifically designed
for wave-front coded imaging systems and a simple Cooke
triplet-based prototype system was established to verify theeffectiveness of the procedure. As a result, the effectiveness ofthe procedure has been tested by experiment. For instance, for a
focal length of 50 mm and f-number 4.5, objects within the range[5 m, ∞] are clearly imaged with the help of wave-front coding,which indicates a DOF extension ratio of approximately 20. The
proposed super-resolution reconstruction procedure produces
at least 3? resolution improvement, with the quality of thereconstructed super-resolution image approaching the diffraction
limit.

10021-43, Session Post

Development of miniature high-collimatedsolar simulator
Pengsong Zhang, Beijing Institute of Spacecraft
Environment Engineering (China); Danyi Wang, Beijing
Institute of Spacecraft Environment Engineering (China);
Bolun Zhang, Linhua Yang, Beijing Institute of Spacecraft
Environment Engineering (China)
The solar simulator is used to simulate the outer space solar
radiation characteristics. The beam angle of so-called highcollimated solar simulator is consistent with that of the outerspace solar radiation, which is widely used in the ground test andaccuracy calibration of sun sensors. Commonly the irradiance canReturn to Contents

Follow us on:achieve a solar constant if the collimation angle of solar simulator
is between 1° and 2°. However, due to the restriction of the designof the solar simulator, the irradiance is only about 0.1 to 0.3 solar
constant when the collimation angle is 32’.
This study optimizes the energy efficiency of optical integrator
and the collimator system using theoretical calculations andthe optical simulation software. The difficulty to get thereal collimation angle and high solar radiation at the sametime is overcome. So the veritable simulation of space solar
characteristics is possible. The irradiation on target surface
should possess the characteristics of real solar radiation, solar
angle, spectral distribution, irradiation stability, uniformity.
The miniature high collimated solar simulator discussed in thisstudy is mainly composed of optical system, mechanical system,
electronic control system and cooling system. The coaxial
optical system with vertical light Xenon lamp is used. After being
converged by ellipsoidal condenser, the beam from Xenon lamp
is deflected to the optical integrator by the reflecting mirror, andthen the field lens of optical integrator images the ellipsoidal
condenser on the projector lens of optical integrator, while theprojector lens images the field lens at infinity. The collimatinglens images the field lens to the irradiation surface, so realizes
accurate collimation beam simulation. In addition, the optomechanical system ensures reliable position of optical system,and the electronic control system provides the current requiredby Xenon lamp to control the irradiance, and the cooling system
is used to cool the optical system and opto-mechanical system.
As a result, an irradiance of 0.8 solar constant at the collimation
angle of 32.2’, with 4.65% irradiation uniformity, and 1.93%/h
irradiation stability in ?200mm irradiation surface are realized in
the miniature high collimated solar simulator developed in thisstudy, which effectively overcomes the technical problem to get
the real solar angle and high irradiance at the same time, andprovides a reliable test platform for the high precise calibration of
the sun sensor in the satellite control system.

10021-44, Session Post

Full-field calibration and compensationof lateral chromatic aberration based on
unwrapped phase
Xiaohong Liu, Shujun Huang, Hebei Univ. of Technology(China); Zonghua Zhang, Hebei Univ. of Technology(China) and Univ. of Huddersfield (United Kingdom);Feng Gao, Xiangqian Jiang, Univ. of Huddersfield (United
Kingdom)
Optical measuring technique, such as 3-D shape measurement
and machine vision have been widely studied in academics andapplied in industries due to its advantages of non-contact, fastacquisition and high accuracy. Cameras are the dispensabledevices in these techniques, especially color cameras can capturecolor texture and shape data simultaneously. However, images
captured by color camera have the phenomenon of chromaticaberrations (CA) and lead to lower precision. Therefore, it is vital
how to compensate for CA of a color camera.
This paper presents a novel method to full-field calibrate lateral
CA between color channels by using unwrapped phase data.
Closed circle sinusoidal fringe patterns having the optimum
three-fringe numbers are generated and displayed on a liquid
crystal screen consecutively through red, green and blue
channels. These closed fringe patterns are captured by a color
camera. The wrapped phase and unwrapped phase of each pixel
can be calculated by using four-step phase shifting algorithm
and optimum three-fringe number method, respectively. The
pixel deviations produced by lateral CA are computed bycomparing the obtained absolute phase data between red, blue,and green channels in polar coordinate system and calibration isaccomplished in cartesian coordinate system. Lateral CA between#PhotonicsAsia

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Conference 10021: Optical Design and Testing VIIcolor channels of the color camera can be compensated by using
the calibrated data. Simulated and experimental results show thevalidity of the proposed calibration method.

10021-47, Session Post

10021-45, Session Post

Analytical calculation of light scatteringfrom randomly rough Gaussian surfaces
according to slope probability

A design of panoramic lens system torealize the projection from the local
annular object field to rectangle image
field by using freeform surfaces
Xuqi Bian, Tao Ma, Jun Zhang, Soochow Univ. (China)
Since the early 1980s, people around the world began to study
the Panorama Imaging System. Panoramic Imaging System canbe defined as an optical system whose field of view is greaterthan 180° or equal to 360° in the vertical or horizontal direction.
Nowadays, a panoramic annular lens (PAL) applies in aerospace,robotics vision, industrial pipeline endoscope and corporate
video conferencing. A cylinder-to-plane projection which called
the Flat Cylinder Perspective(FCP) is adopted in PAL. The FCP
projected the three-dimensional cylindrical field object onto a
two-dimensional annular image plane. The optical system has
fade zone in the center of detector. Based on the structure of the
PAL system, this paper shows that an annular lens is designedwith free-form surfaces. In the designed optical system, thelocal annular object field of view is projected onto a rectangularimage plane. The annular lens has a wide field of view of 180° in
horizontal direction and a field of view of 40° in vertical direction.
The design of the annular lens can maximize the use of area andhave no fade zone in rectangular detector.

10021-46, Session Post

Measurement of optical return loss basedon optical time domain
Qiang Sun, Ji-song YAN, Zhi-hui Zhang, Qiang HAN,
Dong-sheng Wang, The 41st Institute of China Electronics
Technology Group Corp. (China)
As laser communication technologies and dense wavelengthdivision multiplexing (DWDM) systems evolve rapidly, thebandwidth of optical fiber communication is much broader than
before. To ensure the stable propagation, we should characterize
all the optical components, including connectors, couplers,
switches and so on. Among the component characteristics,
backreflection contributes to overall power loss, degrades
laser performance and interferes with voice and video signal
processing. Optical return loss (ORL) can be used to describe thecharacteristic of backreflection. Several measurement principles
and methods are introduced to measure ORL. Among them,
the technique based on optical time domain is widely used.
The technique can be divided into two categories, one is using
optical time domain reflectometer (OTDR), and the other is using
optical reflection discrimination (ORD). This paper will describe
the differences between these two methods in measurement
principle, sensitivity and measurement result. OTDR methodmeasures the backscatter level of the fiber media itself and thereflection peak level of reflective events along the fiber link.
It offers an estimate of the strength of a reflection at a given
distance based on its peak height. OTDR method is suitable forcharacterizing long distance fiber links with sufficient space
between the multiple reflections. ORD method measures theincident and reflected optical powers of reflected events. It
can eliminate the influence of the backscatter signals of thefiber media itself, so the measurement result can reach up to
80dB. ORD method is typically optimized for measuring shortlength optical links like patch cords, pigtails, and other discrete
components. Conclusions of this paper can be the guidance74

for selecting the proper optical return loss meter for ORL
measurement.

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Zhen Gang Yan, Xi’an Modern Control Technology
Research Institute (China); Keding Yan, Xi’an Univ. ofTechnology (China); Liang Xue, Shanghai Univ. of ElectricPower (China); Shouyu Wang, Jiangnan Univ. (China)
As light scattering from randomly rough surfaces is of great
importance in wide fields such as remote sensing, polarized
imaging and target identification, etc., both experimental andnumerical approaches are used to describe the details of thelight scattering process. Among these approaches, numericalcalculations can simulate the scattering distribution withoutcomplex experimental setups and complicated operations,thus they become important tools in light scattering studies.
Method of moments and Kirchhoff approximation methods
are representatives of these approaches, as they can provide
extremely accurate light scattering, however, they still sufferfrom the long time-consuming and large calculation load.
These disadvantages limit their future applications in dynamic
measurements and high speed detections. Here, in order toovercome these disadvantages, analytical calculation of lightscattering from randomly rough Gaussian surfaces according toslope probability is presented in this paper. Compared to otherlight scattering numerical approaches, the proposed techniqueuses the statistical parameters of randomly rough surfaces
directly without computing the ensemble average from numerous
scattered fields, which can obtain light scattering parameterswith high accuracy, but much less time consuming. Additionally,
not only the light scattering distributions can be obtained, thepolarization parameters as Mueller matrix can also be retrieved,
indicating the proposed method can provide more details of
the randomly rough surface information. We believe the paper
provides a useful approach for light scattering study and offers
potentiality in real time light scattering testing.

10021-48, Session Post

Three-dimensional illumination system for
tomographic particle image velocimetry
Fen Zhang, Yang Song, Xiangju Qu, Yunjing Ji, Zhenhua
Li, An-zhi He, Nanjing Univ. of Science and Technology(China)Tomographic particle image velocimetry (Tomo-PIV) is a new
developed technique for three-component three-dimensional(3C-3D) velocity measurement of the flow field based on the
optical tomographic reconstruction method , and received
extensive attention of the related industries at home and abroad.
Three-dimensional light source illuminates tracer particles offlow field is a critical application for tomographic particle image
velocimetry. Three-dimensional light source not only determines
the size of measurement volume which corresponding to thescope of application, but also has a great influence on the image
quality.In this work, we proposed a rectangular light amplification
system based on prisms combination and two reflectors.The
rectangular light amplification concept is verified experimentallyby measuring the cross section size of the illuminated lightsource.The system can be optimized through the basis oftheoretical model research and provides an estimation of some
important system parameters. A 60mm*25mm cross section ofrectangular three-dimensional light source can be obtained bywww.spie.org/pa·

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Conference 10021: Optical Design and Testing VII

using the rectangular light amplification system .The results show
the feasibility and advantages of the system.

10021-49, Session Post

Design of precise assembly equipment oflarge optical components
Pei Guoqing, Xu Xu, Xiong Zhao, Weifeng Du, Yan Han,
Ye Lang, Zhou Hai, Xiaodong Yuan, China Academy ofEngineering Physics (China)
High-energy solid-state laser is an important way to achieveinertial confinement fusion research. With the development ofhigh power laser technology, the optical components of modern
high-energy solid-state laser has become larger and larger. Laser
fusion facility includes thousands of various types of large opticalcomponents. To make sure the device works safely and reliably,
these large optical components should be installed with highprecision and high efficiency. Currently the assembly of large
optical components is by man’s hand which is in low level ofautomation and labor-intensive.
The large optical components are very fragile, heavy andexpensive. We analyzed the actual operating conditions andtechnical principles of the assembly of large optical element.
According to the characteristics of the precision assembly oflarge optical components. We designed a new kind of grasping
device which are used to complete the assembly of large opticalcomponents. Flange, vacuum chuck, chuck installation andconnection components, the clamping cylinder and translation
cylinder, vacuum pump, filter, solenoid valves, vacuum line
were designed. The layout of pneumatic system is arranged.
We simulated the impact of the grasping device on the PVvalue and the RMS value of the large optical components whichindicated that the deformation of the large optical components
were within a reasonable range. The structural strength of thegrasping device’s key parts were analyzed which indicated thatthe strength of the main support plate was enough to keep thedevice safely. An experiment was performed to illustrate thereliability and precision of the grasping device.

10021-50, Session Post

On freeform configuration to improvesystem resolution
Hua Liu, Luoyang Institute of Electro-Optical Equipment(China)Freeform system theory and its influence on aberration andcontrol, is the basis to develop such a system design, which
has application value in engineering aspects. The principle
approach, modeling, and error analysis are analyzed, and thesystem configuration based on freeform is advanced in algorithm
analysis. For to improve the resolution of the imaging system,
and achieve the theoretical limit, we introduced the technology
principle of super resolution restructure from the point of viewon theory and engineering. Several methods to realize highresolution restructure configurations are introduced based ontheoretical analysis and engineering practice. Then, three kindsof restructure technologies, that prototype, micro scanning andsub pixel are described, and how to decrease their shortcomings
are discussed in detail. Furthermore, to improve the band widthby reconstruction without the spectral alias in super resolution
technologies, a new coding technology combining a opticalencoding and the sub pixel is proposed. With the global method,
the bandwidth has been amplified by ten times as compared withthat of traditional ones. Simulation results show that the system
can meet the application requirements in MTF, REA, RMS andother related criteria. Compared with the conventional design,
the system has reduced in volume and weight significantly.

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Therefore, the determining factors are the prototype selection
and the system configuration combined optical, electronic andsignal processing technologies, and as an important developing
trend.

10021-51, Session Post

Slope error tolerance analysis for candela
distribution of total-internal-reflection
collimating lens
Tao Luo, Gang Wang, Sun Yat-Sen Univ. (China)
The total internal reflection (TIR) lens is one of the most widelyused collimating optical devices for LED with small beam angles
and high CLIs. Little work is concerned with how the slope-error
distribution impacts the performance of certain LED collimators,
especially the angular candela distributions.
This paper presented a general concentration standard index(GCSI) which is introduced as a metric for analyzing the luminous
intensity at certain angle, both locally and globally.
Firstly, a Three-Dimensional (3D) slope error tolerance model for
TIR lens is constructed as the extended work of the 2D model
proposed by the authors, and then the local concentration
standard index (GCSIL) for various angles and locations on TIR
curve are calculated.
Secondly, the slope error sensitivities for luminous intensity for
different angels is derived by integration from GCSIL with all
positions at the TIR curve and how the slope error impact on the
angular candela distribution can be obtained.
Thirdly, the slope error impact on the Beam angle (the Full Widthat Half Maximum luminous intensity (FWHM)) and the Filed
Angle (the Full Width at 10% Maximum luminous intensity) , arealso considered by this theory. The results revealed that the Beam
Angle is decreased at first and then increased with the increased
slope error, whereas the Filed angle is monotonically increasing
with the slope errors.
According theory has been well demonstrated with Monte Carloray tracing due to RMS uniformity as low as 1.8% for Beam angle
and 2.23% for Filed angle.

10021-52, Session Post

calibration research of focal length
measurement using Talbot interferometer
Hongying Fan, Hao Zhao, Hao Chen, Zhewei Jiang, Jing
Jia, Southwest Institute of Technical Physics (China)
In this paper, the math model is built for focal length
measurement using an interferometer based on the Talbot effectand the Moiré technique. From this model, a series of methods
is presented to calibrate primary systemic parameters of whichmeasurement uncertainty composes mainly. These parameters
include the distance between the first grating and the tested
optical system, the distance between the two gratings, theangle between the grating ordinate and the camera ordinate,
the angle of two gratings, the angle of moiré fringes, and therate of two grating pitches. The calibrating procedure of acertain interferometer has been practised, getting a certain
result of measurement uncertainty of 2% (k=2) in the scaleof 500 meters. An experiment designed for validating themeasurement uncertainty is described. A knife-edge instrument
also with the measurement uncertainty of 2% (k=2) is applied
to affirm the real focal spot of 30 meters to 500 meters. The
experiment shows that the measurement results of calibrated
Talbot interferometer and that of knife-edge instrument satisfy
the comparison equation. As a result, the analysis of themeasurement uncertainty is rational, the method is practicable,
and the measurement results are traceable.
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Conference 10021: Optical Design and Testing VII

10021-53, Session Post

Simultaneous null test of primary mirror
and three mirror in off-axis three mirror
Yajun Niu, Jun Chang, Weilin Chen, Benlan Shen, Beijing
Institute of Technology (China)
The null test of off-axis mirror plays a very important role in offaxis three mirror design. The detection device depends on either
complex detection optical system designs or high-precision nulllens design. Both can only test one off-axis mirror and are not
non-universal. In order to increase the detection efficiency, weinnovatively propose a simultaneous null test method of primary
mirror and three mirror in off-axis three mirror. The simultaneousnull test device is composed of a zoom null lens and a special
computer generated hologram (CGH) plate. The special CGH
plate has two sub-regions which are corresponding to the two
off-axis mirror. The simulation result of an off-axis three mirror
detection example show that the simultaneous null test method
is feasible.

10021-54, Session Post

10021-56, Session Post

Polarization properties of cat’s eye
retroreflector with three-dimensional
Jones matrix method

Measurement for diffraction efficiency of
convex gratings
Peng Liu, Xinhua Chen, Jiankang Zhou, Zhicheng Zhao,
Quan Liu, Chao Luo, Xiaofeng Wang, Weimin Shen, Minxue
Tang, Soochow Univ. (China)

Yuegang Fu, Yahong Li, Wenjun He, Jiayuan Liu,
Changchun Univ. of Science and Technology (China)
We presents the geometrical performance analysis of Cat’s-eye
retroreflector (CER) in this paper, including the relationship torefractive index, normalized incident height and divergenceangle, which provides tips for optimizing the design of CER.
Furthermore, the polarization property of CER plays a critical role
in related engineering application. For example, when it is used inpolarization interferometer, it’s polarization property will reduce
the signal-to-noise ratio. If CER is applied in laser resonator, thepolarization degree of emitted laser is directly influenced, evenproducing the phenomenon of depolarization. In this paper,
we have studied a detailed three- dimensional polarization ray
tracing of CER based on the three-dimensional Jones matrix
and vector Snell’s law, and the layouts of output polarization
state, retardance and diattenuation of CER in the exit pupil havebeen investigated. The calculated results have showed that the
maximum retardance is 0.3°, the maximum diattenuation is 0.027,
which have had almost no influence on the output polarization
state. Finally, We have made some simulations of the output
polarization states of CER with different input polarization states.
For example, horizontal Linear, 45° linear, circular and ellipticalpolarization state have been analyzed by using simulation
software FRED. The simulation results have indicated that theoutput polarization state remains unchanged with different
input polarization states of CER, which is consistent with thetheoretical analysis. Therefore, CER can be equivalently viewed asa polarization maintaining component.

10021-55, Session Post

Dong Li, Chao Bi, Yajun Jiang, Jianlin Zhao, Northwestern
Polytechnical Univ. (China)
By using the total reflection prisms with the reflectivity close to
one hundred percent instead of the stack of alternated highindex and low-index multi-dielectric layers, the total reflection

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Imaging spectrometers with convex gratings which can offer fast
apertures and small volume systems synchronously have received
a great deal of attention both in China and abroad, because of
the increasingly development of convex grating manufacturetechniques. They can be applied as remote sensing instrumentsin the areas of mineral exploration, agriculture, forestry,
environment hazards assessment, urban study and so on.
As one of the most important properties of convex gratings,
diffraction efficiency has a direct impact on energy transmission
characteristics of imaging spectrometers. Compared with planegratings, convex gratings are formed upon convex substrates that
results in different measurement methods of diffraction efficiency
which have been rarely reported in China.
In this paper, a new measuring system for diffraction efficiency
of convex gratings and its principle are proposed and described.
This system mainly consists of a stable light source, relay system,
Offner spectrometer, and data-processing system. By using thissystem, the intensity of diffraction signals over an extended
spectral range from a convex grating can be detected during
one exposure cycle. After setting up the measurement system
and accomplishing the laboratory spectral calibration, thediffraction efficiency of a convex grating with an aperture of 35mm, curvature-radius of 72mm and a grating period of 5 ?m istested. In the end, the comparison and error analysis between thetheoretical calculations and the testing data are carried out toprovide the technical basis for the further manufacture of convex
gratings and imaging spectrometers.

10021-57, Session Post

Characterization on the effect of linear
stress birefringence in a total reflection
prism (TRP) ring resonator

76

prism (TRP) ring laser gyroscope can motivate the ongoinginterest in inertial navigation systems (INS) community andpromote an increase in the service life and a reduction in thestart-up time of a laser gyroscope. However, the TRP resonator
put forward higher requirements on the co-planarity of the beamreflective point on the four prisms. The resonator consisted of theprisms is the core component of the gyroscope whose precision
can be affected by the slightly residual stress and the errors ofstructure parameters during the processing and adjustment of
the resonator and prisms, etc. In this paper, based on the theory
of Jones matrix and the condition of eigenmode self-consistency,
we analyze the effect of linear stress birefringence of prism on
the beam polarization (described with the ellipticity and lossof the eigenmodes) and null drift (described with the output
frequency difference of the eigenmodes) in a TRP resonator. The
results show that the linear stress birefringence of prisms cancause larger polarization ellipticity for both CW (clockwise) andCCW (counter clockwise) beams, which has nothing to do with
the nonplanar angle. Meanwhile, the direction of stress has someinfluence on beam polarization ellipticity and null drift. These
interesting results are useful for the designing and optimizing thestructure of super high precision TRP ring laser gyroscopes.

·

Research on detecting plankton based on
darkfield microscopy
Buyu Guo, Jia Yu, Ocean Univ. of China (China)
Plankton is an important part of the marine life, which plays asignificant role in studying the change of global climate and themarine ecological environment. However, once plankton leaveswww.spie.org/pa·

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Conference 10021: Optical Design and Testing VII

the original living environment, it is extremely vulnerable todeath and the refractive index of plankton is highly close to therefractive index of the ocean. This makes it very difficult to detectplankton by the bright field microscopy.
This problem can be resolved by the darkfield microscopy,
which allows only oblique rays from every azimuth to “strike”
the specimen and let the field of view appear dark. Meanwhile
the darkfield microscopy with high resolution can help to detect
the plankton in a smaller size. To achieve accurate and effective
detection of plankton, we build the Underwater Darkfield
Microscopy Detection System. This system is composed of twoparts: light cabin and receiver cabin that are connected througha cable. The battery is located in the light cabin to generatehollow light cone for illuminating. The receiving compartment
includes microscopic imaging amplification unit and storage unit,
capturing the image by CCD.
We start by collecting samples from the coast of Qingdao andthen use the resolution board to confirm the performance andresolution of the underwater darkfield microscopy detection
system. We detect plankton from the collected sample to obtain
their shape information. The resolution of our system is about
181lp/mm.

10021-58, Session Post

Design, assembly, and metrology of an oilimmersion microscope objective with long
working distance
Wei-Jei Peng, Wen-Lung Lin, Hui-Jean Kuo, Cheng-Fang
Ho, Wei-Yao Hsu, Instrument Technology Research Ctr.
(Taiwan)
The design, fabrication, assembly, and optical metrology for an
oil-immersion microscope objective with long working distance
employed in a lattice light-sheet microscope are presented.
In this application, the orthogonal excitation and detection
objectives are dipped in an oil medium. The excitation objective
focuses incident laser beam to excite fluorescence on specimen
for collecting by detection objective. The excitation objective
in our study is custom-designed to meet the requirement
specification of oil-immersion, long working distance, andnumerical aperture (NA) of 0.5, etc. To produce an acceptable
point spread function (PSF) for efficient excitation, theperformance of the objective needs to be close to diffraction
limit. Therefore modulation transfer function (MTF) at high spatial
frequency should be kept after assembly. It is difficult because
the tolerance is much more sensitive at higher spatial frequency.
Consequently, tolerance budget must be considered in the designphase, the criterion of optical design is based on as-built optical
performance in our study for ensuring quality after fabrication
and assembly. Furthermore, the opto-mechanical design andassembly method are also discussed. Afterward, the objectivewith five spherical lenses was fabricated and assembled. In
optical metrology, the focus of the objective is immersed in
the oil, so it leads to measured result sensitive to the depth ofoil medium. For solving the issue, we made an index-matchinglens to replace oil for ensuring accuracy measurement andavoiding complex mechanical adjustment. Finally, the measured
optical performance of the excitation objective in our study canaccomplish the requirement specification and successfully used
in a lattice light-sheet microscope.

10021-59, Session Post

Tilt displacement range testing for apiezoelectric deformable mirror

at Shenzhen, Tsinghua Univ. (China); Fan Fan, Heng Li,
Beijing Institute of Technology (China)
In our previous works, we presented a zoom system and image
stabilization design based on deformable mirrors (DMs).
According to the high bandwidth and free edge characteristicsof the piezoelectric deformable mirror (PDM), we tested thesystem’s image-stable capability. We found the PDM could realize
some tilt displacements while keeping a certain stable surface
shape, it could obtain higher image stabilizing precision when
integrated with the traditional mechanical image stabilization
systems. In the design of the image stabilization system, the
PDM’s tilt displacement range is a key factor for consideration.
So in this paper, we carried out a tilt displacement range testing
experiment by using the OKO’s 37-channel PDM. We measured
and analyzed the variation of the tilt displacements in opticalimage stabilization process, and calculated the maximum tilt
angle as the PDM surface shape was stabilized. We built anexperimental platform consisting of a fixed target, an imaging
system based on PDM, and a CCD camera. We used the
ZYGO interferometer as an evaluation instrument to measure
the surface shape stability. When the PDM surface had a tilt
displacement, the image point of the fixed target on the camera
sensor shifted correspondingly. The tilt angle of the PDM could
be obtained by calculating this shift. The results showed thatthe maximum tilt angle of the PDM was 0.2mrad. The paper also
analyzed the experiment errors when concerning about the offaxis error of the PDM deflection center.

10021-60, Session Post

Optical design of Offner-Chrisp imaging
spectrometer with freeform surfaces
Lidong Wei, Jinsong Zhou, Juanjuan Jing, Lei Feng, Yacan
Li, Academy of Opto-Electronics, CAS (China)
Imaging spectrometers are novel radiation sensors that provide
a collection of spectral images of inhomogeneous scenes. The
Offner-Chrisp spectrometer is the preferred optical configurationin many spectroscopic imaging applications because it has
several advantages over other similar instruments. However,the diffraction grating makes the Offner-Chrisp imaging
spectrometer asymmetric in the meridional plane, and theastigmatism becomes the dominant residual aberration.
Moreover, the images of different wavelengths are not flat
along the slit can decrease the imaging quality and difficult forassembly.
Freeform surfaces enable imaginative optics by providing
abundant degrees of freedom for an optical designer ascompared to spherical surfaces, and offer many advantages inimaging application, e.g. superior image quality, compact andlightweight designs. An Offner-Chrisp imaging spectrometerwith freeform surfaces is designed in this paper. The imaging
spectrometer works at the wavelength range from 200 to
1000nm. The freeform surfaces are used to reduce the residual
aberration over the large wavelength range and achieve a large
flat field simultaneously. The design starts from a sphere OffnerChrisp system, and then the freeform surfaces are applied
to optimize the initial configuration by the use of an opticalsoftware package. Different types of freeform surfaces are
considered to evaluate their potential, e.g. anamorphic aspheres,
Q-polynomials of Forbes, X-Y polynomial and Zernike polynomial.
Benefits from the freeform surfaces, the residual aberrations arewell corrected, especially in the UV region and a flat field over
the wide wavelength range is also obtained. The image quality
is near diffraction limits. For evaluating the manufacturabilityof the freeform surfaces system, the aspheric departures ofeach freeform surface are also evaluted which meet the current
manufacturing capacity.

Dongdong Wang, Qun Hao, Yong Song, Beijing Instituteof Technology (China); Xuemin Cheng, Graduate School

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Conference 10021: Optical Design and Testing VII

10021-63, Session Post

Design of a holographic waveguide with L
configuration
Guangxin Xiang, Wenqiang Li, Luoyang Institute ofElectro-Optical Equipment (China)
In order to decrease the complexity to design and manufacture
the gratings of single plate with single reflecting surface, an
L-shape two-dimension extended configuration with single
plate is given in the paper. This configuration consists of two
specular reflecting surfaces and three holographic gratings ofwhich period and the groove orientation are totally same, whichmakes gratings design and fabrication easier. According to thecalculation and analysis to the optical path of configuration, thedimension of the turning grating is no larger than 40mm?40mm.
The simulation result demonstrates the display configurationis reasonable and correct and can realize the display effectwith 30°?30° field of view and ?30mm large exit pupil. Thisconfiguration can be applied to an Augmented Reality Display(AR) or a Head-Mounted Display (HMD).

10021-65, Session Post

Design and Analysis of Conical Diffraction
Imaging Spectrometer with High Spectral
Resolution
Qiao Pan, Qinghan Liu, Zhicheng Zhao, Weimin Shen,
Soochow Univ. (China)
Owing to the use of CCD linear image sensor of rectangle
pixels, the spectral dispersive width of spectrometer is usuallymuch longer than the spatial one, sometimes up to dozens ofor hundreds of times. In this case, traditional in-plane Offner
mounting is no longer satisfied because of dramatic increasing
astigmatism and distortion. To meet these special needs,
conical diffraction Offner mounting, one kind of off-plane
Offner mountings, in which the incident light plane parallel tothe direction of the grooves of the grating, is presented. Wave
aberration theory is applied when analyzing the initial parameters
related to the structure of spectrometer. Consequently, an
optimal design is proposed later by utilizing the formal results, ofwhich the focal ratio is 4 at the spectral region of 400?1000nm
while slit length 500?m and dispersive width 21mm. To evaluate
the overall image quality changing along with the angles between
incident and diffractive plane, the entrance slit length and thespectral width, the merit function and spectral response function
are considered under no obvious changes in the spectrometer’s
total volume. At the end of the design instance, comparative
analyses between in-plane and conical diffraction Offner
mountings are presented as well. Finally, conclusions are given
about the application scopes of these two configurations.

10021-67, Session Post

Afocal three-mirror anastigmat withzigzag optical axis for widened field-ofview and enlarged aperture
Qi Li, Han Lin, Yangming Jin, Weimin Shen, Soochow Univ.
(China)In order to improve the detection accuracy and range of new
generation of Forward Looking InfraRed (FLIR) system for
distant targets, its optical system, which usually consists of a fore
afocal telescope and rear imaging lenses, is required to has wide
spectral range, large entrance pupil aperture, and wide field ofview (FOV). In this paper, a new afocal Three-Mirror Anastigmat(TMA) with widened field of view and high demagnification issuggested. Its mechanical structure remains coaxial, but it has
zigzag optical axis through properly and slightly decentering andtilting of the three mirrors to avoid its secondary obscuration due
to the third mirror as FOV increase. Compared with conventional
off-axis TMA?the suggested zigzag-axis TMA is compact, easyalignment and low-cost.
The design method and optimum result of the suggested afocal
TMA is presented. Its initial structural parameters are determinedwith its first-order relationship and primary aberration theory.
Slight and proper decentration and tilt of each mirror is leaded in
optimization so that its coaxial mechanical structure is held but
attainable FOV and demagnification are respectively as wide andas high as possible. As an example, a 5.5-demagnification zigzagaxis afocal TMA with a wavelength range, an entrance pupil
diameter, and FOV respectively from 3 um to 12 um, of 320mm,
and 2?4 degrees and with real exit pupil, is designed. Its imaging
quality is diffraction limited. It is suitable for fore afocal telescopeof the so-called third generation FLIR.

10021-68, Session Post

10021-66, Session Post

Design of refractive fore-optics with wide
field-of-view and waveband for miniature
imaging spectrometer
Jingchao Mao, Minyi Xu, Qinghan Liu, Weimin Shen,
Soochow Univ. (China)
With the development of UAV remote sensing technology?
compact high-resolution imaging spectrometer will be more
and more popular. It is urgent to design and develop fore-optics
with wide field of view for miniature broad spectrum imaging
spectrometer which can improve the efficiency of remote sensing
and get wider coverage. The refractive system has high luminous

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flux and it is conducive to manufacture and assemble. Our focus
is on the correction of secondary spectrum and meeting therequirement of imagery telecentricity which is appropriate forlinear pushbroom imaging system. Based on the third-orderaberration theory, it calculates the power of individual elementsof the objective lens with minimized longitudinal chromaticaberration in a broad spectral range. Moreover, this paper derives
equations to calculate the radii of curvature of superachromatic
optical system with a required value of spherical aberration andcoma. Finally, optimized refractive SWIR fore-optics working in
1-2.5?m with effective focal length (EFFL) of 11mm is reported. Its
full field, F-number are respectively 40°, F/2.8. The system has
many advantages such as simple and compact structure?near
diffraction-limited imaging quality?small secondary
spectrum?and imagery telecentricity. Especially it consists ofspherical surfaces that can greatly reduce the difficulty and costof manufacture and test, which is applicable for SWIR imaging
spectrometer with wide field of view.

SPIE Photonics Asia·

Assembly and alignment of highresolution spaceborne optical system
Wang Kai Guo, Min Wang, Feng Lin, Fujian Normal Univ.
(China)Based on a high-resolution spaceborne optical system
researched and developed independently, this paper puts
forward a method called detecting instrument and computer
aided separated assembly and alignment. It uses a variety ofhigh-precision detecting instruments to test the parameters of
optical components and system, and then select the qualified
component to match in groups. Adjust the main errors what
are the air gap error between lenses and the eccentric error in

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Conference 10021: Optical Design and Testing VII

assembly. Divide the optical system into some small lens groups
and their residual error can be compensated by adjusting the air
gap between lenses. Use the detecting instrument to measure
the MTF after assembly and alignment. The result shows that the
optical system meets the design requirements and its pixels are
more than 20 million. This alignment method is also suitable forother high-resolution coaxial optical system.

10021-70, Session Post

Optical design of a dual-channel twofocal-length system by utilizing azimuth
property of PAL structure
Chen Xu, Dewen Cheng, Yongtian Wang, Beijing Instituteof Technology (China)
An approach to design a dual-channel two-focal-length lens
based on the panoramic annular lens (PAL) structure is presented
in this paper. The method of establishing the second channel toeliminate the blind area has been explored in some documents,and mostly it is achieved by utilizing the front surface of the PAL
block. But in this paper, we modified the PAL block and divided it
into two channels according to their different azimuth direction.
These two channels have different focal lengths. Thus, by rotating
the system around its axis, optical step-zoom effect can beobtained. Finally, a dual-channel system with a zoom ratio of 3?
is designed, of which the wide-angle channel has a field-of-view(FOV) of 60° (radial) ?90° (azimuthal) and the long focal length
channel has a FOV of 20° (radial)?20° (azimuthal). These twochannels share the same stop surface, relay lens, and the image
sensor. And a thin glass plate with diffractive structure is placed
before the image plane to further correct aberration and obtaina common back focal length for the two channels. This system
may have applications in many fields, such as surveillance, robot
vision, and foveal imaging.

10021-71, Session Post

Study of 700mm-diameter primary mirror
based on topology optimization andsensitivity analysis
Xin Wang, Xiaoying He, Lei Feng, Juanjuan Jing, Jinsong
Zhou, Academy of Opto-Electronics, CAS (China); Wei
Wang, Xi’an Institute of Optics and Precision Mechanics,
CAS (China); Yacan Li, Academy of Opto-Electronics,
CAS (China); Wei Lidong, Academy of Opto-Electronics,
Chinese Academy of Sciences (China) and Academy of
Opto-Electronics, CAS (China)
The primary mirror is an important optical component of spacecamera. It’s performance related to the optical image quality,
and it’s weight directly affects the camera weight. The traditional
method of designing primary mirror relies on much experience,and many design parameters obtained by empirical formulas. The
method lacked precise theory, and the performance of the result
is unstable. Therefore, the method of designing primary mirror
should be optimized. For this study, a primary mirror made of
SiC with a diameter of 700mm was conceptual designed in themethod of topological optimization firstly. The design goal is to
fully guarantee the quality of the structural strength and also theshape of mirror surface under the premise of minimum weight.
The structure of topology optimization has completely met thedesign requirements. But due to the topological optimizationis conceptual design, which cannot determine the specific sizeof configurations. In order to further enhance the performanceof the mirror, sensitivity analysis is carried out to determine theoptimum thickness of the back muscles. Divided back tendons

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into three categories according to the distribution location. The
sensitivity of primary mirror stiffness to the three categories
tendons was analyzed, and then the optimum thickness of thetendons was found. Finally, the optimum primary mirror fully
satisfied the required optical performance was designed, which
has better mechanical performance and the lighter weight. A
companion between the optimum primary and traditional primary
was made and the results showed that, the optimum primary has
higher lightweight ratio increased by 5%, higher modal frequency
increase by 81Hz.The maximum deformation under gravity parallelto the optical axis reduced by 48nm, PV of the mirror surface
reduced by 8.1nm and RMS reduced by 3.1nm. Put forward thetarget of temperature control through the thermal analysis.
All the result data indicates that this optimization method in thepaper is reasonable and effective, which gives a reference to theprimary mirror design in the future.

10021-72, Session Post

Wavefront sensing for sparse aperture
imaging system based on sub-aperturephase diversity
Junliu Fan, Quanying Wu, Jun Wang, Suzhou Univ. of
Science and Technology (China); Baohua Chen, Soochow
Univ. (China)
The phase diversity wave-front sensing (PDWFS) technique is aposteriori image-based wave-front sensing method which has
been successfully implemented to the Hubble Space Telescope, itutilizes two images collected simultaneously whose pupil phasediffers from each other in a known manner, typically the focus
diversity. Here, we introduce a new method of implementing
phase diversity on sparse aperture imaging system that utilizes
control of the sub-apertures. Instead of adding defocus phase to
the image, intentional piston or tilt errors are introduced to one
sub-aperture with respect to the others, the objective function is
firstly derived for the sparse aperture imaging system, then thegenetic algorithm is used to minimize the objective function toestimate the errors of the sub-apertures. Digital simulations are
conducted for varying amounts of diversity and levels of noise.
The performance of sub-aperture phase diversity is evaluatedby comparing with the conventional focus diversity. The results
show that the sub-aperture phase diversity performs better thanthe conventional focus diversity at low noise level, while focus
diversity performs better at high noise level, in the computationalburden aspect, the sub-aperture phase diversity takes lessiterations than conventional focus diversity and therefore
achieves higher computational efficiency. Sub-aperture phase
diversity may be an useful alternative if the primary focus phase
diversity method fails.

10021-73, Session Post

Depolarization of laser beam propagating
through atmosphere based on multiple
Rayleigh scattering model
Zhang Dai, Electronic Engineering Institute (China);
Hao Shiqi, Lei Wang, Qi Zhao, Electronic Engineering
Institute (China) and State Key Lab. of Pulsed Power Laser
Technology (China)
An analytical formula model which is used to describe laser
beam’s depolarization characteristics is solved based on multiple
Rayleigh scattering model. Firstly, by using Stokes vector
to characterize intensity and polarization, while at the sametime using Mueller matrix and rotation matrix to characterizepolarization changing in scattering procedure, a single scattering#PhotonicsAsia

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Conference 10021: Optical Design and Testing VII

model is built. Then, a multiple scattering model is built
considering the effects of atmospheric absorbing and scattering
attenuation. The received light’s Stokes vectors through multiple
scattering procedure are separately solved. At last, on the basisof multiple scattering vectors, the depolarization characteristics
of laser beam propagation through atmosphere are estimatedthough calculating ratio of depolarization and polarizing angle
shifting. The numerical analysis based on analytical conclusionof this paper shows that for a horizontal polarized laser beam,
its ratio of depolarization is about 1% and polarizing angle
shifting is about 0.3? when propagates through atmosphereand arrives into the receiver on the ground and both the above
characteristics have only a small change compared with thechange of cloud’s depth. The findings of these research showthat Rayleigh scattering from atmosphere has a weak effecton the laser beam’s polarization status. The multiple scatteringmodel and Stokes vector analytical formulas raised in the paper
could also be used to study the depolarization characteristics ofellipse polarized laser beam and partially polarized laser beam
propagating through atmosphere. The research findings of thispaper will have theoretical guiding significances in the domain oflaser communication, laser detection and laser imaging.

10021-74, Session Post

Mean likelihood estimation of target
micro-motion parameters in laser
detection
Liren Guo, Yihua Hu, Yunpeng Wang, Institute of ElectricalEngineering (China)First of all,a closed-form expression to evaluate the parameterswhich maximize the cost function is derived based on thethiory of mean likelihood function. Then the compressed
likelihood function is designed to obtain the global maximum,
mainly through exponeniating the cost function and adjust theconstant factor. This compressed likelihood function acts like aprobablity density function that ensures the global convergence.
Finally?the Monte Carlo sampling method is used to generate
the random variables subject to the distribution obtained
from the compressed likelihood function. The parameters areultimately estimated by calculating the circular mean of therandom variables. Simuation and experiment results show that
this method is able to reach the Cramer-Rao Bound and acquire
similar performance as Maximum Likelihood Estimation with lesscomputational amount.

10021-75, Session Post

Research on focusing properties of multivortex phases vector beam loading withdifferent topological charges
XianYi Zhang, Xiaoping Yang, Tianjin Univ. of Technology(China)The inhomogeneous polarization distribution of vector field
makes a great impact on the spatial-temporal evolution and leads
to many novel phenomena and effects, which is different withthe scalar beam, such as that the radially polarized field could
be highly focused into a sharper spot with strong longitudinalcomponent, the azimuthally polarized field could be highly
focused into two-dimension and three-dimension hollow focal
field. In addition, we also can adjust and control the light field,
which mainly involves the polarization and phase control. In thispaper, the phase control of vector beam namely load vortex
phase is researched and simulated.
In this paper, we deduced the focusing field formula of the multivortex phase vector beams loading with different topological

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SPIE Photonics Asia·

charges based on the Richards-Wolf vector diffraction theory.
It is found that when the Gaussian radial vector field symmetricloading double vortex, three vortex and four vortex along the xaxis, it can generate one, two and three optical dark-field in thefocusing field respectively.and it can be used in the multi particle
capture.We loaded different topological charges on the vortex
phases,and adjusted the energy distribution of the focusing spotby changing the topogical charges.This feature can be used in thefield of multi particle manipulation and fine control of laser micro
maching

10021-76, Session Post

Design of photonic crystal Fizeau
interferometer using self-collimation
effectJun Wang, Suzhou Univ. of Science and Technology(China) and Soochow Univ. (China); Xiao Yuan, Soochow
Univ. (China)
A Fizeau interferometer based on the self-collimation effectof two-dimensional air-cylinder photonic crystal (2D PhC)
is demonstrated theoretically. The back ground index of thesquare-type lattice PhC is 3.5 and the radius of the air holes r0= 0.26a, where a is the lattice constant. The structure of PhC
leads to its self-collimation effect, by which the lights propagate
in the interferometer. The Fizeau interferometer includes one
total reflection PhC mirrors and two defect row splitter, shown in
Fig.1. Compared with non-common optical path interferometer(e.g. Michelson and Sagnac), Fizeau is a type of common optical
path interferometer, therefore the machining errors of opticalpaths lead to little influence on the interference intensities. The
equi-frequency contours (EFCs) of the PhC are calculated byusing the plane-wave expansion(PWE) method, and interference
properties are investigated by using the finite-difference timedomain(FDTD) method. The transmission spectra at output
port is in the shape of sinusoidal curves in the frequency range
from 0.26c/a to 0.27c/a shown in Fig.2, whose peak spacing isdetermined by the optical path difference of the interferometer.
For the operating wavelength around 1550nm, the dimensionsof this interferometer are only tens of microns. The proposedinterferometer is sensitive to the refraction index changes in the
optical path, which make it possible to be sensors.

10021-77, Session Post

Light concentrator of the wide field-ofview Cherenkov telescope
Rui Yang, Xiyi Sheng, Bollin Liao, Yunnan Univ. (China)
The Wide Field of View Cherenkov Telescope (WFCT) is an
important components of the project of Large High Altitude AirShower Observatory (LHAASO) in Gamma ray astronomy. WFCT
is mainly constituted by optical reflector and photomultiplier(PMT) array camera located on the focal plane of optical system.
In order to avoid loss of Cherenkov signal resulting from thedead area between circular PMT tubes and invalid fringe of each
PMT, the light concentrator used as front window of PMT arrayis considered to improve detective efficiency. Basing on theedge-ray principle and features of WFCT, four types of single
concentrator, such as circular light cone, hexagonal light cone,
compound parabolic concentrator (CPC) and hexagonal CPC aredesigned and simulated in the non-sequential mode of ZEMAX.
Furthermore, the focusing effect of the light concentrator arraysin practical optical path of WFCT is also simulated in the mixedsequential mode of ZEMAX. The result shows that the hollow
hexagon CPC has good performance in focusing and collecting
light. Moreover, the samples of the hollow hexagon CPC havebeen manufactured and tested. The experiment result turns

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Conference 10021: Optical Design and Testing VII

out that 30% collection efficiency has been promoted with thehollow hexagonal CPC, comparing with the detector without light
concentrator.

10021-78, Session Post

Research on simulation and analysis of theparallax of visual optical system
Qiang Ji, You Long, Xiaoxia Li, Xiaohong Liu, Haijun
Zhang, Liang Zhou, AVIC Luoyang Institute of ElectroOptical Equipment (China)
The features of visual optical system used for the near-eye
display device is that the images at position of human eyes
are formed to infinity. The parallax of visual optical system willaffect the observation comfort and display accuracy in particularsituation. In this paper, we proposed a simulation calculation
program of parallax with tunable accuracy and rapid convergenceaccording to the the theoretical analysis of parallax mechanism.
The autonomic computing of parallax and position accuracy
at any field of view within the range of exit pupil was achievedby such calculation program. The validity and accuracy of thecalculation program were verified by calculating and simulating
the typical off-axis visual parallax optical system.

10021-79, Session Post

The water colority measurement based on
HSV chromaticity
Jun Wang, Yang Pan, Quanying Wu, Fan Wang, Suzhou
Univ. of Science and Technology (China); Fan Jun liu,
Suzhou Univ of Science and Technology (China)
A method of measuring water colority based on HSV
chromaticity (H hue, S saturation, V value) system is proposed.
The measurement system is composed of halogen lamp, sample
cell and spectrometer. The spectrum data of transmission
light captured by spectrometer is used to calculate the XYZ
tristimulus values which is then converted to HSV chromaticity.
The colority and saturation value are studied, which shows agood linear relationship between them. Therefore the colority canbe calculated by the saturation. Since the hue value is acquiredat the same time, the method is adopted to water sample
with different hue. Moreover, the V value is an independent
component, so the instability of light source has no influenceon the measurement. The linear relationship is calibrated in theexperiment, and the colority obtained by the calibrated linear
function coincides with the standard solution.

10021-80, Session Post

Tomato seeds maturity detection system
based on chlorophyll fluorescence
Cuiling Li, Zhijun Meng, Xiu Wang, Beijing Academy ofAgriculture and Forestry Sciences (China)
Seeds chlorophyll fluorescence intensity can be used as seeds
maturity and quality evaluation indicator, in order to judge thechlorophyll content of high and low level in seeds, and further
to judge seeds maturity, chlorophyll fluorescence intensityof seeds epidermis is measured and analyzed. This researchdeveloped a tomato seeds maturity detection system basedon chlorophyll fluorescence including an excitation light source
unit, a fluorescent signal acquisition unit and a data processing
unit. Excitation light source unit was used for tomato seeds
fluorescence excitation, which was made up of high power LEDs,

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Follow us on:radiators and constant current power supplies. Fluorescentsignal acquisition unit consisted of a fluorescence spectrometer,an optical fiber, an optical fiber holder and a narrowband filter.
Data processing unit included a computer. This study harvested
tomato fruits at different ripeness periods and used them
directly to produce seeds of different maturities. This researchused the developed tomato seeds maturity testing system tocollect fluorescence spectral information of tomato seeds ofdifferent maturities, first derivative (FD), Savitzky-Golay (SG)convolution smoothing methods were utilized to pretreat
fluorescence spectrum data. Principal Component Analysis (PCA)
method was adopted to reduce the dimensions of spectral data,
extract principal components, and it was combined with linear
discriminant analysis (LDA) to establish discriminant model oftomato seeds maturity, discriminant accuracy was above 90%.
Research results showed that using chlorophyll fluorescence
spectroscopy is feasible for seed maturity detection, and thedeveloped tomato seeds maturity testing system has highdetection accuracy.

10021-81, Session Post

Effect of mixed atmosphere on theproperties of InGaZnO thin-films
Chenghan Li, Li Wang, Beijing Univ. of Technology (China)
The effect of oxygen and argon on amorphous indium-galliumzinc-oxide(IGZO) thin films is investigated. IGZO ceramic target
was prepared by mixing the In2O3, Ga2O3, and ZnO powders
at a mol ratio of 0.8:0.05:0.15, the target obtained by solid-state
reactions in atmospheric pressure, pulsed laser deposition(PLD)
method was applied to grow amorphous IGZO films. IGZO thinfilms on Al2O3 substrates in a mixed atmosphere of Ar and O2
at fixed 10Pa working pressure. X-ray diffraction (XRD) patterns
show that both films with an amorphous structure independentof the atmosphere composition. The transmitted spectrum showsa clear Burstein-Moss shift dependent on the change of mixed
atmosphere. The average transmittance in visible wavelengths ofall films is higher than 90%. The maximum carrier mobility was
found to be 10.42 cm2 V?1 s?1 in thin film with mixing the Ar andO2 gas ratio of 1: 3

10021-82, Session Post

Space-time adaptive system: architecture
method and operation support
Hua Liu, Luoyang Institute of Electro-Optical Equipment(China)Along with the development on the artificial intelligence,
augmented reality of academic research and business, to therequirement of the multidisciplinary integrated is becoming
more deeply. Space-time adaptive methods, and their expansionof the aspects of application and operation platform, areextending from the traditional space-time system design to thestructured devices, augmented reality, virtual reality, artificial
intelligence and open Internet and so on, while with the physicalsystem, social system more closely together. This kind of system
configuration, development method and running environment
has some typical characters, such as open, dynamic and difficult
to control, and requires that the software and hardware systems
need to have a certain degree of adaptive capacity. That is to
say that software and hardware systems should be able to takethe initiative to perceive the change of the environment and thedemand, and adjust their own structure and behavior, according
to this with continued low offering services to meet users expect(or even exceed). In this report, based on the holographic beam
tracing technology, the core technology system on real scene wasbuilt, which can not only provide realistic reappearance effect,#PhotonicsAsia

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Conference 10021: Optical Design and Testing VII

but also confirmed a practical application. By predicting theframework of reproduction and how to apply the tracing process,the key problems of technology are analyzed, summarized andpredicted. In recent years, the space-time adaptive softwareand hardware system of related theory, method, technology andapplication is getting attention of academia and industry. We set
up the space-time adaptive theory based on space photoelectric
control method of the purpose is to integrated our research andideas in the development of space-time adaptive system method
and the latest achievements in aspects of operation support andto promote further work.

10021-83, Session Post

Fumin Wang, Meng Shi, Nan Chi, Fudan Univ. (China)
Visible light communication (VLC) is one of the hottest research
directions in wireless communication. It is safe, fast and freeof electromagnetic interference. We carry out the visible light
communication using DFTS-OFDM modulation mode through theheadset port to and take equalization technique to compensate
the channel. In this paper, we first test the feasibility of the DFTSOFDM modulated VLC system by analyzing the constellationand the transmission error rate via the headset interface ofthe smartphone. Then we change the peak value of the signal
generated by the AWG as well as the static current to find thebest working point. We tested the effect of changing the upsample number on the BER performance of the communication
system, and compared the BER performance of 16QAM and
8QAM modulation in different equalization method. We also
do experiment to find how distance affect the performance ofthe communication and the maximum communication rate thatcan be achieved. We successfully demonstrated a visible light
communication system detected by a headset port of a smart
phone for a 32QAM DFTS-OFDM modulated signal of 27.5kb/sover a 3-meter free space transmission. The light source istraditional phosphorescent white LED. This result, as far as weknow, is the highest data rate of VLC system via headset port
detection.

10021-84, Session Post

An interactive VR system based on fullbody tracking and gesture recognition
Xia Zeng, Xinzhu Sang, Duo Chen, Peng Wang, Nan Guo,
Binbin Yan, Beijing Univ. of Posts and Telecommunications(China)Most current virtual reality (VR) interactions are realized with thehand-held input device which leads to a low degree of presence.
There has been other solutions using sensors like Leap Motion
to recognize the gestures of users in order to interact in a morenatural way, but the navigation in these systems is still a problem,
because they fail to map the actual walking to virtual walking
only with a partial body of the user represented in the synthetic
environment. Therefore, we propose a system in which users canwalk around in the virtual environment as a humanoid model,
selecting menu items and manipulating with the virtual objects
using natural hand gestures. With a Kinect depth camera, oursystem tracks the joints of the user, mapping them to a full virtual
body which follows the move of the tracked user. The movementsof the feet can be detected to determine whether the user is inwalking state, so that the walking of model in the virtual world
can be activated and stopped by means of animation control in

SPIE Photonics Asia

10021-22, Session 5

The optical legacy of Imperial College
London (Invited Paper)
Tina E. Kidger Webb-Moore, Kidger Optics Associates(United Kingdom)

Demonstration of DFTS-OFDM andequalization technology using in VLC
communication via the headset port ofandroid device

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Unity engine. This method free the hands of users comparing totraditional navigation way using hand-held device. We use thepoint cloud data getting from Kinect depth camera to recognize
the gestures of users, such as swiping, lifting and manipulating
virtual objects. Combining the full body tracking and gestures
recognition using Kinect, we achieve our interactive VR system inUnity engine with a high degree of presence.

·

The Industrial Revolution, incubated primarily in the UK,
generated an increasing need for highly skilled technical people.
Throughout the 19th century, technical instruction increased
dramatically and the formation of schools specializing in scienceand technology grew simultaneously. In England, there was much
motivation in favour of a national prestige center for science andtechnology centered in London. Central among the motivating
forces was Queen Victoria’s husband, Prince Albert. Although
there were already existing specialist science and technology
institutions in major English cities, the growth of superior
institutions in other countries within Europe, especially Germany
and the Charlottenburg area of Berlin (e.g., the Berlin TechnicalHigh School), encouraged important English dignitaries tobecome more competitive with continental Europe. As a result of
this strong continental motivation several science and technology
institutions were built in the South Kensington part of London
during the latter half of the 19th century. Imperial College,
founded at the start of the 20th century, was a culmination andconsolidation of several of these 19th century English institutions.
Optical science and technology was an early beneficiary of thefounding of Imperial College.
One important way to experience the development and influenceof Imperial College in the discipline of optics is through its
exceptional scientists and engineers. We look at the people who
were instrumental in the founding of Imperial College London
in the late 19th and early 20th century, who saw the need for auniversity which would advance technical training. The reasonsfor the formation of the Optics Section in1917 followed in 1919
by the first course in technical optics in Britain to be set up at
Imperial College. This paper seeks to highlight IC’s founders
and early scientists who made this happen and illustrates theconsiderable permeation of their contributions throughout
international optics today.

10021-23, Session 5

Illumination analysis of LAPAN’s IR
microbolometer
Bustanul Arifin, Andi M. Tahir, Irwan Priyanto, Indonesia
National Institute of Aeronautics and Space (Indonesia)
We have since 2 years ago been doing a research in term of an
IR Micrometer Bolometer which aims to fulfill our office, LAPAN,
desire to put it as one of payloads into LAPAN’s next microsatellite project, either at LAPAN A4 or at LAPAN A5. Due to thelack of experience on the subject, everything had been initiatedby spectral radiance analysis adjusted by catastrophes sources inIndonesia, mainly wild fire (forest fire) and active volcano.
Based on the result of the appropriate spectral radiancewavelength, 3.8 – 4 ?m, and field of view (FOV), we, then,went through the further analysis, optical analysis. Focusing
in illumination matter, the process was done by using Zemax
software. Optical pass Interference and Stray light were two

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Conference 10021: Optical Design and Testing VII

things that become our concern throughout the work. They
could also be an evaluation of the performance optimization ofillumination analysis of our optical design.
The results, graphs, show that our design performance isclose diffraction limited and the image blur of the geometrical
produced by Lapan’s IR Micro Bolometer lenses is in the pixel
area range. Therefore, our optical design performance is relatively
good and will produce image with high quality. In this paper, theIllumination analysis and process of LAPAN’s Infra Red (IR) Micro
Bolometer is presented.

10021-24, Session 5

Balancing deflection angles in the designof LED refractive optics with two freeform
surfaces
Sergey V. Kravchenko, Kseniya Andreeva, Mikhail A.
Moiseev, Leonid L. Doskolovich, Image Processing
Systems Institute (Russian Federation)
The use of LEDs in the modern lighting devices makes the
problem of designing secondary optics quite relevant. For the
purpose of street, industrial and emergency lighting opticalelements with two free-form surfaces are usually used. In
this study the method for computation of such LED optics is
proposed. In this approach the optical element surfaces aredesigned sequentially: firstly the inner surface is computed andthen the outer one. At the beginning of each surface computationa piecewise smooth solution should be designed. Such a surface
generates discrete intensity distribution that approximates thecontinuous one. In order to compute piecewise smooth solution
we propose to utilize the supporting quadric method. After wehave had piecewise smooth surface the smooth one is obtainedby fitting NURBS-spline on it. Such a method allows controllingthe balance of deflection angles between the inner and outersurfaces. It has been proven that in the case of point source,
the maximal efficiency is obtained when each surface performs
the half of the required ray deflection. As an example, theoptical element with equal ray deflection part in each surface
generating intensity distribution for ME1 class roadway lighting isdesigned. The simulation results of the luminance and illuminancedistribution confirm good quality of the proposed method.

10021-25, Session 5

Analytical design of reflective opticalelement generating a prescribed intensity
distribution
Egor V. Byzov, Samara State Aerospace Univ. (RussianFederation) and Image Processing Systems Institute(Russian Federation) and LED Optics Design LLC (RussianFederation); Evgeny S. Andreev, Mikhail A. Moiseev, Image
Processing Systems Institute (Russian Federation) andSamara State Aerospace Univ. (Russian Federation) and
LED Optics Design, LLC (Russian Federation); Leonid
L. Doskolovich, Nikolay L. Kazanskiy, Image Processing
Systems Institute (Russian Federation) and Samara State
Aerospace Univ. (Russian Federation)
In this paper a new kind of source-target map for design mirrors
generating prescribed two-dimensional line-shaped intensity
distributions is presented. Line-shaped means that distribution
is defined in region with a high aspect ratio, obtained fromthe line by direct replacement for each point on the segment
perpendicular to the reference. This map is a generalizationof the mapping, used in the well-known problem of reflective

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optical elements design generating one-parameter intensity
distributions. Design examples show high performance of the
proposed method, including for areas with a small aspect ratio.
For rectangular and elliptical intensity distributions with angulardimensions from 80°x20° to 40°x20° the relative standard error
does not exceed 8.5%

10021-26, Session 5

Visual analysis of the computer simulation
results for both imaging and non-imaging
optical systems
Boris K. Barladian, M. V. Keldysh Institute of Applied
Mathematics (Russian Federation); Igor S. Potemin,
Dmitry D. Zhdanov, ITMO Univ. (Russian Federation);
Alexey G. Voloboy, Lev Z. Shapiro, Ildar V. Valiev, Elisey D.
Birukov, M. V. Keldysh Institute of Applied Mathematics(Russian Federation)
Typical simulation results of the computer systems of the virtual
prototyping and realistic rendering are images generated on thevirtual sensors of various kinds. As a rule, these images represent
two-dimensional distribution of the light values in Cartesian
coordinates (luminance, illuminance) or in polar coordinates(luminous intensity). Using virtual sensors allows making the
calculation and design of different kinds of illumination devices,
providing stray light analysis, synthesizing of photorealistic
images of three-dimensional scenes under the complex
illumination generated with optical systems, etc.
Based on rich experience in the development and practical usingof computer systems of virtual prototyping and photorealistic
rendering the authors formulate a number of basic requirements
for the visualization and analysis of the results of light simulations
represented as two-dimensional distribution of luminance,
illuminance and luminous intensity values. The requirements
include the dynamic range compression, pseudo color imaging,visualization of the spherical panorama, regression analysis,
the analysis of the image sections and regions, analysis of pixel
values, the image data export, etc. All those requirements weresuccessfully satisfied in designed software component for visual
analysis of the light simulation results. The module “LumiVue” isan integral part of the “Lumicept” lighting simulation system andthe corresponding plug-in of the CATIA computer-aided design
product.
A number of visual examples of analysis of calculated twodimensional distribution of luminous intensity, illuminance andluminance illustrate the article. The examples are results ofsimulation and design of lighting optical systems, secondary
optics for LEDs, stray light analysis, virtual prototyping andphotorealistic rendering.

10021-27, Session 6

Self-mixing interferometry and its
applications (Invited Paper)
Yanguang Yu, Yuanlong Fan, Bin Liu, Univ. of Wollongong(Australia)
This paper reviews the self-mixing interfereometry (SMI) in
terms of its operation principle, the features of SMI signals
and its configuration. Self-mixing refers to a phenomenon that
occurs when a small fraction of the light emitted by a laser isbackscattered or reflected by an external target and re-enters
the laser active cavity, thus leading to the modulation of thelaser output power. This is a remarkably universal phenomenon,
occurring in lasers regardless of type. A few application examples
are presented based on the research work done in our group,#PhotonicsAsia

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Conference 10021: Optical Design and Testing VII

including SMI sensing for measuring displacement, material
parameters and laser parameters. An SMI with the laser operating
at the relaxation oscillation is also introduced which has potential
for achieving more sensitive sensing.

Measurement of optical systemaberrations based on randomly-encodedhybrid grating
Jiabin Jiang, Tong Ling, Yongying Yang, Rui Zhang,
Zhejiang Univ. (China)
A lateral shearing interferometer based on randomly encodedhybrid grating (REHG) is proposed to measure the opticalsystem aberrations. According to the theory of Fraunhofer
diffraction, the REHG is designed to be a combination of arandomly encoded binary amplitude grating and a phasechessboard. Compared with the conventional cross-grating
lateral shearing interferometer, the REHG is more suitable forthe general aberration testing since no order selection mask
is needed. Collimated beam for aberration measurement will
converge after passing through the optics system under test.
Then the quadriwave lateral shearing interferogram containing
the wavefront aberration information is then recorded by the
CCD. By selecting its +1 order of the Fourier spectrum in both X
and Y directions, the shearing wavefronts in both two orthogonal
directions can be obtained employing phase unwarping
algorithm. Zernike polynomials are used as basic functions for theoriginal wavefront, and the coefficients of Zernike polynomials
can be obtained with shearing wavefronts. In the experiment,
we employed a REHG with a grating pitch of 240 um to test acemented doublet optics with an aperture of 50mm and a focal
lengths of 90mm. The test results showed the peak-to-valley(PTV) aberration is 0.242?while the root-mean-square (RMS)
is 0.064?. The test results by the REHG are very close to theresults by the ZYGO GPI interferometer while the error of PTV
is 0.003?and the error of RMS is 0.007?. The measurement of
optical system aberrations by REHG can reach high precision andexhibit good immunity to environmental disturbance. The REHG
can be applied to the optical testing of beam quality, opticalsystem aberration and biomedical research.

SPIE Photonics Asia·

An eight-channel Kirkpatrick-Baez
microscope for plasma diagnostic
Yaran Li, Baozhong Mu, Qing Xie, Qiushi Huang, Zhanshan
Wang, Tongji Univ. (China); Jianjun Dong, Zhurong Cao,
Shenye Liu, Yongkun Ding, China Academy of Engineering
Physics (China)

10021-28, Session 68410021-30, Session 6

Kirkpatrick-Baez (KB)-type x-ray microscope proves to be anadvantageous tool for plasma diagnostic in inertial confinement
fusion (ICF) experiments. We have designed, manufactured
and tested an 8-channel KB-type x-ray microscope for use at
the Shenguang-?(SG?) laser facility. The reflecting elementsare 3 pairs of concave spherical mirrors accurately arranged toreflect and focus x-ray emitted from laser plasma. Customized
substrates and specially-made pyramid was fabricated andtested in order to materialize its strict optical design. The single
superpolished substrate (<5 Å r.m.s roughness) has dimensionsof 30?10?8mm and is coated with a C/W periodic mutilayer,
providing high reflectivity at specific grazing incident angle at
8 keV. Laboratory results show its spatial resolution is ~3?m atbest focus and better than 5?m over a 300-?m-diam region
which agrees well with ray tracing. Combined with X-ray framing
camera, the time evolution of the imploded target has also beenrecorded at SG? with a time interval of 80ps. The eight-channel
KB microscope proves to be a high-resolution, high-throughput
x-ray imaging system. This article provides detailed information
about the optical design, assembly method and experimental
results of the microscope.

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10022 Holography, Diffractive Optics, and Applications VII

10022-1, Session 1

Common-path digital holographic
microscopy and its applications (Invited
Paper)
Jianlin Zhao, Jianglei Di, Northwestern Polytechnical Univ.
(China)Digital holographic microscopy (DHM) has become a novel toolwith advantages of full field, non-destructive, high-resolution
and 3D imaging, which captures the quantitative amplitude andphase information of microscopic specimens. Its applications
are manifold and include biological microscopy, microstructures
metrology, and so on. It’s a well-established method for digitalrecording and numerical reconstructing the full complex fieldof wavefront of the samples with a diffraction-limited lateral
resolution down to a few hundreds of nanometers depending on
the numerical aperture of microscope objective. Meanwhile, its
axial resolution through axial direction is less than ?/50 due tothe interferometric nature in phase imaging.
In this paper, we summarize the principles of DHM, discuss
some key technologies in its optical-mechanical design, analyze
traditional optical configurations including Mach–Zehnderinterferometer and Michelson interferometer, and apply thistechnology to measure microlens arrays, laser mark and pit,
microcantilevers, MEMS devices, and so on. Besides this,to significantly increase the stability of the interferometer,
common-path configurations with a piece of glass plate, calcite
crystal or Lloyd mirror are introduced in DHM to make up acompact experiment system. Meanwhile, dual-wavelength
technique and some numerical algorithms are also employed
to improve the measurement accuracy. Experiment results ofpollen and osteoblast cells show the feasibility of the proposed
configuration.

10022-2, Session 1

Super-resolution imaging in opticalscanning holography using structured
illumination (Invited Paper)
Zhenbo Ren, Edmund M. Y. Lam, The Univ. of Hong Kong
(Hong Kong, China)
As a specific digital holographic microscopy system, opticalscanning holography (OSH) is an appealing technique thatmakes use of the advantages of holography in the applicationof optical microscopy. In OSH system, a three-dimensional
object is scanned with a Fresnel zone plate in a raster fashion,and the electrical signals are demodulated into a complex
hologram by heterodyne detection. Then the recorded light
wavefront information contained in the hologram allows one todigitally reconstruct the specimen for multiple purposes such as
optical sectioning, extended focused imaging as well as threedimensional imaging. According to Abbe criterion, however,akin to those conventional microscopic imaging systems, OSH
suffers from limited resolving power due to the finite size of theobjective lens and the aperture, i.e., low numerical aperture. To
bypass the diffraction barrier in light microscopy, various superresolution imaging techniques have been proposed. Among thosemethods, structured illumination is an ensemble imaging conceptthat modulates the spatial frequency by projecting additional
well-defined patterns with different orientation and phase shiftonto the specimen. Computational algorithms are then applied toremove the effect of the structure and to reconstruct a superresolved image beyond the diffraction-limit. In this paper, weReturn to Contents

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introduce this technique in OSH system to scale down the spatial
resolution below the diffraction limit. The performance of the
proposed method is validated by simulation and experimental
results.

10022-3, Session 1

Imaging characteristics of selfinterference digital holography withstructured illumination
Ying Han, Yuhong Wan, Beijing Univ. of Technology(China); Hongqiang Zhou, Beijing University ofTechnology (China) and Institute of Information Photonics
Technology (China); Fan Wu, Tianlong Man, Beijing Univ.
of Technology (China)
Self-interference digital holography enables hologram-recordingof object illuminated with spatially incoherent light by special
beam splitting methods. Among them, Fresnel incoherent
correlation holography(FINCH) has great potential of superresolution microscopic imaging. In order to achieve the goal ofsuper-resolution, some techniques have been proposed, such as
dual-lens FINCH, FINCH combined with confocal imaging systemand so on. Structured illumination microscopy(SIM) is a kind of
method that can achieve super-resolution imaging and opticalsectioning imaging simultaneously. By introducing a sinusoidal
fringe patterned light, it can record high frequency information
beyond the diffraction limit of a system to achieve superresolution imaging. In this paper, the imaging characteristics of
FINCH with structured illumination are investigated in detail.
The super-resolution imaging principal of FINCH with structured
illumination are firstly demonstrated. The effects of structured
light pattern, including the period, modulated direction andmodulation depth of sinusoidal pattern on imaging lateralresolution are also investigated. The resolution improved whenincreasing the frequency of sinusoidal pattern until it is equal
to the cut off frequency of the system, and by increasing themodulation depth, the resolution also become better. The
image reconstructed from two(like 0°and 90°) and four(like 0°,45°, 90°and 135°) pattern orientation is shown in the paper at
the same time. This work offers great reference for 3D superresolution microscopy in the near future.

10022-4, Session 1

Digital in-line holographic microscope
based on the grating illumination withimproved resolution by interpolation
Shaodong Feng, Mingjun Wang, Jigang Wu, Shanghai Jiao
Tong Univ. (China)High resolution is always a pursuing target in the imaging
field, as a newprospective technique in imaging applications,digital in-line holography has become a very active field forcompactness, more information and low-cost. However, forcompact system, the resolution is often limited by sensor
pixel size. To overcome this problem, we propose an iterative
reconstruction method with data interpolation based on thegrating illumination. In our method, the Talbot self-image ofa Ronchi grating is exerted in the sample plane as a priori
constraint which lead to the convergence of the iteration, theiteration between the sample plane and the sensor plane canprovide some extra information with interpolation in the sensor
plane based on the a priori constraint, furthermore, the iteration#PhotonicsAsia

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
reconstruction can also eliminates the twin-image to improve
the image quality. Numerical simulation has been conducted toshow the effectiveness of this method. In order to make a further
verification, we have developed a lensless in-line holographic
microscope with a compact and wide field-of-view design. In
our setup, the sample was under the Talbot image illumination of
the Ronchi grating, which was illuminated by a collimated laser
beam, and holograms were recorded by a digital imaging sensor.
We can shift the grating laterally to get a wide-field image. We
demonstrated the resolution of our imaging system by using the
USAF resolution target as a sample, and the results shown the
resolution improvement of the image.

10022-10, Session 1

Processing of digital holograms:
segmentation and inpainting

10022-6, Session 2

Noise reduction performance of thecompressive digital one-shot in-line
holographic tomography (Invited Paper)

Shuming Jiao, Wenbin Zou, Shenzhen Univ. (China)
In modern holography, a hologram can be acquired, processed,
stored and reconstructed all in digital forms. Various hologram
image processing techniques can be developed with regard
to the specific image properties of digital holograms. In thispresentation, the author will explore two novel hologram image
processing issues, i.e., hologram decomposition and hologram
inpainting.

Hua Zhang, Liangcai Cao, Hao Zhang, Guofan Jin,
Tsinghua Univ. (China)

By hologram decomposition, one hologram can be decomposed
into several sub-holograms and each sub-hologram represents
one individual item in the 3D object scene. In this presentation, a
Virtual Diffraction Plane (VDP) based hologram decomposition
scheme is proposed. By Otsu thresholding segmentation,
morphological dilation and sequential scan labelling, a VDP backpropagated from hologram can be divided into sub-VDPs andeach sub-VDP can be reverted to be a sub-hologram. At thesame time, an alternative VDP cutting approach is proposed as asupplementary method. This automatic hologram decomposition
scheme is further employed for focus distance detection in blind
hologram reconstruction. It is free of “Shading Effect” and has
better accuracy and reliability.
By hologram impainting, a damaged hologram can be restoredby filling in the missing pixels. In this presentation, an exemplar
and search based image inpainting technique is applied for the
restoration of heavily damaged digital off-axis Fresnel holograms.
An intelligent search technique, Artificial Bee Colony algorithm, isemployed to significantly increase the computation efficiency of
the inpainting process. Experimental results reveal that with this
proposed method, the pictorial information in heavily damaged
holograms can be recovered with good fidelity. In addition,
Morphological Component Analysis (MCA) inpainting algorithm is
proposed for hologram restoration when the missing regions arenoise-like separate missing pixels instead of scratch lines or holes.
Three potential application cases of hologram inpainting are
discussed including occlusion recovery, hologram watermarking
and QR code restoration.

10022-5, Session 2

Digital holographic amplification ofmodified Jamin (Rozhdestvensky)
interferograms
Dmitriy V. Venediktov, Sergey A. Pulkin, Saint Petersburg
State Univ. (Russian Federation); Alexander A. Sevryugin,
Ibragim M. Tursunov, Vladimir Y. Venediktov, SaintPetersburg Electrotechnical Univ. “LETI” (RussianFederation)
Digital holography provides a lot of opportunities fortransformation of interferometric information. One can increase
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SPIE Photonics Asia

the interferometer sensitivity by “amplification” of holographic
fringes’ deformations, remove the distortions, imposed byinterferometer elements, provide digital summation or extractionof interferograms, modify the spatial carrier frequency etc.
However, to the moment this technique was applied mainly to theinterferometers, measuring height of distortions, distance to theobject or its movement parameters. We consider the prospectsof applying similar approaches in the case of spectroscopyinterferometery. This idea was investigated in the experimentwith the use of modified Jamin interferometer, working together
with spectrograph (this device is also known as Rozhdestvensky
interferometer). The results of the experiment has shown thatthe use of holographic multiplication simplifies the analysis ofinterferograms, used investigation of fine structure of spectral
lines.

·

Digital holography (DH) is recently applied to reconstruct 3-D
datacube from a 2-D holographic data in the tomographic
imaging. Digital one-shot in-line holography (DOIH) maintains
the space-bandwidth product, compared with off-axis
holography. However, DOIH suffers from intrinsic defects, suchas twin-image restriction and the squared noise. In this work,
compressive sensing (CS) is applied for DOIH in the tomographic
reconstruction to overcome the above defects. The Fresnel
propagation is employed in the algorithm, which keeps the‘incoherence’ condition for CS measurement. The evaluation of
the reconstructed images at different depths prove the validityof compressive DOIH, compared with the traditional backpropagation method. It is demonstrated that compressive DOIH
has the great capability to strip both the squared noise and theconstant noise from the 2-D hologram. The proposed method has
great potentiality for dynamic imaging of moving micro-organic
particles due to the fast sampling rate of DOIH.

10022-7, Session 2

Three-dimensional edge extraction in
optical scanning holography
Yonghong Zong, Changhe Zhou, Jianyong Ma, Wei Jia, Jin
Wang, Shanghai Institute of Optics and Fine Mechanics(China)Edge extraction has found applications in various image
processing fields where extracting the edge or shape of theobject is of great interest, such as in pattern recognition. Whilethe 4-f system with spectrum modulation is usually used for edge
extraction, the objects being processed are in the same planewith little depth of field. In this paper, a new method is proposed
for edge extraction of three-dimensional objects in opticalscanning holography (OSH). OSH is a two-pupil heterodyne
scanning optical system which traditionally uses a delta function
or a point source and a uniform function or a plane wave as its
pupil functions. Isotropic and anisotropic edge extraction of 3D
objects is simulated using spiral phase plates in OSH operating
in an incoherent mode. We propose to use a delta function anda spiral phase plate as the pupil functions to realize isotropic
and anisotropic edge extraction. The interference of these two
pupils creates a time-varying vortex beam which can be used
to two-dimensionally scan an object to record its edge-only
information. The isotropic edge extraction can be achieved bywww.spie.org/pa·

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
using a spiral phase plates with its center on the optical axis. The
anisotropic edge extracted object can be obtained by shifting theoptical vortex in the pupil plane, by using two offset spiral phase
plates of same charge, or by using two oppositely charged spiralphase plates. Our computer simulations show the capability of
extracting the edges of a given 3D object by spiral phase filteringin OSH.

10022-8, Session 2

Resampling masks for noise reduction inphase-shifting digital holography
Wenhui Zhang, Liangcai Cao, Hao Zhang, Song Zong,
Guofan JIn, Tsinghua Univ. (China)
Holographic imaging is degraded severely by the speckle or
incoherent noise. Using multiple holograms to reconstruct
the original image can decrease noise with an undesired time
consumption. One-shot strategy to reduce noise in digitalholography has been widely investigated recently. One hologramis enough for filtering noise by dividing it into sub-holograms
during reconstruction. An image with lower noise can beacquired through the average of the reconstruction results ofthe sub-holograms. Before divided into multiple parts, the zeroorder of the hologram is filtered in the frequency domain. The
reconstruction results would also be subject to the interferenceof the conjugate term. It is difficult to filter the zero-orderaccurately if three orders of the hologram are overlapping. In thiswork, resampling masks on phase-shifting digital holography is
proposed to reduce the noise and filter the zero-order and the
conjugate term of the hologram. The post-propagated complex
amplitude of objects acquired through four-step phase-shifting
digital holography experiment using a phase-only spatial light
modulator is encoded into several parts by resampling masks. A
high quality reconstruction image with lower noise is achieved
through the superposition of the individually reconstruction ofcoded complex amplitudes. Compared to direct reconstructionof the conventional digital holography, the peak signal to noise
ratio of the results can be increased by 10 dB via the proposed
approach and the reconstructed images become smoother.
This method can be used for digital holographic imaging of thebiological samples and microstructures. Experimental results
prove the feasibility of this proposed method.

10022-9, Session 2

Pixel Super-resolution in digital in line
holography
Mingjun Wang, Shanghai Jiao Tong Univ. (China); Wu
Jigang, Shanghai Jiao TOng Univ, (China); Shaodong
Feng, Shanghai Jiaotong Univ. (China)
In this paper, we report a new holographic microscope using
pixel super-resolution algorithm. In our method, a sequence of
low resolution images are acquired by a complementary metaloxide semiconductor (CMOS) sensor in digital in-line holographysystem and the resolution is limited by the sensor pixel size. Thenthe super-resolution algorithm is applied to the low resolution
images toand get the image with much higher resolution thatbeyond the Nyquist criteria.
In our method, we carried outperform both numerical stimulationand experiments to demonstrate our method with US Air Force
Target in experiment to validate our method used as the sample.
The sample is randomly moved in the sample plane and a set ofholograms are captured with by the camera in inline holographic
system. We use two methods to reconstruct the sample image.
Two experiments are done respectively. In the first method,super-resolution algorithm is processed applied with those thelow resolution images holograms to getting the high resolution

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Follow us on:hologram. Then the high resolution hologram is reconstructedwith using auto-forcusing algorithm to get the high resolution
sample image. In the second method, the raw holograms are
directly reconstructed to get a set of low resolution sample
images, and then the super-resolution algorithm is processed
applied to the reconstructed images to get the high resolution
sample image. With comparisonWe observed that theabovementioned two methods can get similar results, the orderof using super-resolution algorithm does not matter a lot to theresolution of reconstructed image in both numerical stimulationand experiments. We believe that the combination of pixel
super-resolution algorithm and digital in-line holography can bevery promising useful in life healthy protection and diagnosis toimplement a compact low-cost microscope with high resolution.

10022-11, Session 2

Measuring a thermal expansion ofthermoelectric materials by using in-line
digital holography
Thanyarat Thong-on, Prathan Buranasiri, King Mongkut’s
Institute of Technology Ladkrabang (Thailand)
In this paper, the measuring a thermal expansion ofthermoelectric material (TE) CuCrO2 was observed by using
digital holography (DH) technique. In the experimental setup,
diode laser, a digital camera and a sample on hot plate were
set in the same alignment, then called in-line digital holography(DIH). A laser beam was expanded and been parallel through athermoelectric sample, which was heated by a hot plate from aroom temperature to 224 °C, then a set of expanded images ofa TE sample were recorded by a digital camera and numericallyanalyzed data by imaging reconstruction. For the result of thisresearch, thermoelectric material was founded infinitesimal
expanding, and its thermal expansion coefficient (COE) was
founded equal to 2.25 ? 10-6 °C-1.

10022-12, Session 3

A head-mounted compressive threedimensional display system withpolarization-dependent focus switching(Invited Paper)
Chang-Kun Lee, Seokil Moon, Byounghyo Lee, Byoungho
Lee, Seoul National Univ. (Korea, Republic of)
A head-mounted compressive three-dimensional (3D) display
system is proposed by combining polarization beam splitter(PBS), fast switching polarization rotator and micro organic
emitting diode with high pixel density. According to thepolarization state of image controlled by polarization rotator,
optical path of image in the PBS can be divided into transmitted
and reflected components. Since optical paths of each image arespatially separated, it is possible to independently focus both
images at different depth positions. Transmitted p-polarized
and reflected s-polarized images can be focused by convex
lens and concave mirror, respectively. When the focal lengthsof the convex lens and concave mirror are properly determined,
two image planes can be located in the intended positions. The
geometric relationship is easily modulated by the replacementof the components. The fast switching of polarization realizes
the real-time operation of multi-focal image planes with single
panel. Since it is possible to conserve the device characteristicof single panel, the high image quality, reliability and uniformity
can be retained. For generating 3D images, the four-dimensional
light field information for compressive 3D display between two
image planes is calculated. Since the display panel with high pixel
density is adopted and two optically separated image planes are#PhotonicsAsia

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
free from diffraction which limits resolution of layered 3D display
system composed of physically stacked display panels, highquality 3D images are reconstructed. Simple optical configurationof the proposed system is integrated in the prototype of thehead-mounted display system.

10022-13, Session 3

Volumetric display with holographic multiphoton excitations (Invited Paper)
Yoshio Hayasaki, Kumagai Kota, Utsunomiya Univ. (Japan)
Developments of three-dimensional (3D) displays are one ofthe dreams. The realization of a future visually sufficient 3D
display will require some technological innovations. Holographic,
stereoscopic head-mounted displays were the good candidates
for producing effective 3D graphics, but they have a limited
observation area and require users to wear special devices.
Volumetric displays that render 3D graphics can be observed
from any surrounding viewpoints without any wear devices.
They are classified into two light-reflecting and light-emitting
types, depending on the characteristics of the voxels. One of thelight-emitting types was based on a laser addressing, which had
a wide viewing angle and no requirement of wiring between thelaser source and the display material.
We developed a volumetric display composed of a femtosecond
laser for two- and multi-photon excitations to display materials,
an LCSLM that displays a computer-generated hologramfor parallel addressing, a 3D beam scanner composed ofgalvanometer mirrors and a varifocal lens for expanding an
addressing area, and display materials. Some types with different
display materials that were solid, liquid, and gas types were
demonstrated. The solid material had multilayer structures
composed of polymer plates with fluorescent dyes for multicolor display. The liquid material was glycerin for bubble display.
The gas matter was an air for an interactive touchable display.
The main purpose of the holographic parallel addressing was
to increase the number of voxels per unit time, but it had an
addition usefulness of the controls of voxel brightness and size.

10022-14, Session 3

Focus-tunable multi-view holographic
3D display using a 4k LCD panel (Invited
Paper)

A focus-tunable multi-view holographic three-dimension(3D) display system with a large size of 22.3cm?12.5cm and a
resolution of 3840?2160 is presented. It is assumed that 3D
image generation by holographic stereograms is similar to thatof multi-view autostereoscopic displays, in that multiple parallax
images are displayed with rays converging to corresponding
viewpoints. If the multiple rays reconstructing the 3D images
point enter the pupil simultaneously, the eyes can focus on thatpoint according to the depth cue. To achieve the purpose, amethod of synthesizing computer-generated holograms (CGHS)
from multiple perspective projections (parallax images) is
adopted in this paper. It does not require calculations of light

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10022-15, Session 3

Vertical viewing angle expansion using
lenticular lens sheet.
SooBin Kim, Hwi Kim, Korea Univ. (Korea, Republic of)
We propose lenticular lens for holographic display. Integral
image displaying has wide viewing angle, but it has not depth
expression. The lenticular lens is a great help in the verticalviewing angle. The asymmetric diffuser has expansion of verticalviewing angle. But, accommodation effect cannot be expectedin asymmetric diffuser. The accommodation effect is importantin hologram display. Our system has accommodation effectof important thing in the hologram display. The resolution islow, but displaying hologram with a narrow field of view will
be a great contribution. We also made a simulation tool foreverything in lenticular lens sheet. For example, the result of theinteraction with spatial light modulator (SLM) and display panel
and the hologram displaying. Our results of simulation shown
demonstration in experimental results for same. But, lenticularlens sheet has critical problem in hologram displaying. It has
interval that is not the field of observation window, it is called
black term effect. We proposed a solution for black term effectto jittering effect. This paper demonstrates that all important
thing in hologram displaying for simulation and experiment.
The ultimate goal of this paper is perfect expansion of verticalviewing angle using lenticular sheet in hologram displaying.

10022-16, Session 3

Qiaojuan Lin, Xinzhu Sang, Zhidong Chen, PengWang, Beijing Univ. of Posts and Telecommunications(China); binbin yan, Beijing University of Posts andTelecommunications, China (China); chongxiu yu, Beijing
University of Posts and Telecommunications, China,
China (China); wenhua dou, School of Computer Science,
National University of Defense Technology (China); liquanxiao, School of Computer Science, National University of
Defense Technology (??)

88

diffraction. The spherical wave was adopted and the wavefront
converging to a viewpoint on the hologram plane. It has theamplitude distribution of a parallax image and the phase
distribution of the spherical wave. The wavefront of all multiple
viewpoint images are calculated, then they are summed up to
obtain the object wave on the hologram plane. A reference lightis used to converge the central diffraction wave and the firstorder diffraction wave from the liquid crystal display (LCD). The
viewing zone of holograms is between the central and first orderdiffraction wave. Because the distance of adjacent viewing points
is smaller than the pupil diameter, therefore, the system provides
smooth and continuous motion parallax. Experiment resultsshows that the proposed display can construct the 3D objects
with focus cues: accommodation and retinal blur.

Optimization of lens shape forautostereoscopic display
Jianshe Ma, Ping Su, Shu An, Graduate School at
Shenzhen, Tsinghua Univ. (China)
Three-dimensional (3D) displays based on binocular parallax are
drawing increasingly interests. Beam-splitting elements, which
present separate images to the viewer’s left and right eyes, play
an important role in auto-stereoscopic display. Lenticular lensarray is widely used as beam-splitting element. However, thecrosstalk caused by the aberration caused by spherical surface
decreases the 3D experience.
This paper devotes to the optimization of lens shape to obtainbetter beam splitting effect. It is determined that the mostviable cross-sectional shape for the lenticular lenses is elliptical.
Firstly, the formula of the surface, which is , is derived based on
the ellipse equation and the requirement of display system. The
semi-major axis is 17.99mm and the semi-minoraxis is 7.38mm.
Then, the crosstalk is defined as the ratio of the disturbing lightintensity to the total light intensity. A math model is constructed
to simulate the imaging process and calculate the crosstalk.
Simulation result shows that the crosstalk is reduced by 20%,
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Conference 10022:
Holography, Diffractive Optics, and Applications VII
spherical. Besides, the minimum line width can be increasedby 30%, which reduces the difficulty of machining greatly. In
conclusion, the optimization of the surface has a significant effecton the improvement of stereoscopic depth and the reduction of
ghost images.

10022-19, Session 4

Optical scanning holography forstereoscopic display (Invited Paper)Jung-Ping Liu, Hsuan-Hsuan Wen, Feng Chia Univ.
(Taiwan)

10022-17, Session 3

High-aperture diffractive lens forholographic printerAlexander Y. Zherdev, Sergey B. Odinokov, Dmitry S.
Lushnikov, Bauman Moscow State Technical Univ. (RussianFederation); Chermen B. Kaytukov, FSUE “STC” Atlas(Russian Federation)
An optical schema of holographic printer for obtaining ofholographic stereograms with increasing angle of view is
proposed. Conventional holographic printers allows to obtainholographic stereograms with angle of view up to 90°. Proposed
schema allows to increase angle of view up to 120°. The opticalschema is based on diffuser and diffraction optical element
namely high-aperture diffractive lens. The experience of usingof composite holographic lens and binary Fresnel zone plate asa high-aperture diffractive lens is described. Samples of highaperture diffractive lens with aperture f/0.3 are obtained andinvestigated. Samples of holographic stereograms are obtainedusing samples of high-aperture diffractive lens.

10022-18, Session 4

Development of scanning holographic
display using MEMS SLM (Invited Paper)
Yasuhiro Takaki, Tokyo Univ. of Agriculture andTechnology (Japan)
Holography is an ideal three-dimensional (3D) display technique,because it produces 3D images that naturally satisfy human 3D
perception including physiological and psychological factors.
However, its electronic implementation is quite challenging
because ultra-high resolution is required for display devices
to provide sufficient screen size and viewing zone. We havedeveloped holographic display techniques to enlarge the screen
size and the viewing zone by use of microelectromechanicalsystems spatial light modulators (MEMS-SLMs). Because MEMSSLMs can generate hologram patterns at a high frame rate, thetime-multiplexing technique is utilized to virtually increase theresolution. Three kinds of scanning systems have been combinedwith MEMS-SLMs; the screen scanning system, the viewing-zone
scanning system, and the 360-degree scanning system. The
screen scanning system reduces the hologram size to enlarge theviewing zone and the reduced hologram patterns are scanned on
the screen to increase the screen size: the color display systemwith a screen size of 6.2 in. and a viewing zone angle of 11° wasdemonstrated. The viewing-zone scanning system increases
the screen size and the reduced viewing zone is scanned toenlarge the viewing zone: a screen size of 2.0 in. and a viewing
zone angle of 40° were achieved. The 360-degree scanningalso increases the screen size and the reduced viewing zone isscanned circularly: the display system which has a flat screenwith a diameter of 100 mm was demonstrated, which generates
3D images viewed from any direction around the flat screen.

Optical Scanning Holography (OSH) is a nonconventional
digital holographic recording technique. In OSH, a heterodyne
structured light is applied to raster scan a 3D object target, andthe scattered light is recorded and demodulated to generate adigital hologram of the 3D object. OSH can be operated in theincoherent mode. The incoherent-mode of OSH is able to record
speckle-free complex hologram of a 3D object. In addition,
multiple lighting effects can be simultaneously recorded in OSH,
and thus the lighting of the hologram can be modified after theholographic recording. Because of the above unique features, theOSH is a good candidate to record a 3D scene for holographic
display.
The shortcoming of OSH is that the scanning procedure is timeconsuming. To solve the problem, we have proposed to use an
asymmetry pupil in OSH system to limit the vertical bandwidthof the hologram, while the horizontal bandwidth is retained.
Consequently, the vertical sampling rate as well as the scanning
time is significantly reduced. Although the horizontal sampling
rate can be much higher than the vertical sampling rate, it is still
limited due to the unsteadiness of the scanner. As a result, theviewing angle is not large enough for optical display. To solve
this problem, we record two OSH holograms with an angularseparation. The two holograms are synthesized to a single
stereoscopic hologram with two main viewing angles. Because
both views can reconstruct full-depth-resolved 3D scenes, theproblem of accommodation conflict in conventional stereogram
is avoided.

10022-20, Session 4

Three dimensional Identification card andapplications (Invited Paper)
Changhe Zhou, Shanghai Institute of Optics and Fine
Mechanics (China)
Three dimensional Identification Card means that there are threedimensional optical techniques are used, the personal image on
ID card is displayed to be three-dimensional, so we can see three
dimensional personal face. The ID card also stores the threedimensional face information in its inside electronics chip, whichmight be recorded by using two-channel cameras, and it can bedisplayed in computer as three-dimensional images for personal
identification. Three-dimensional ID card might be one interesting
direction to update the present two-dimensional card in the
future. Three-dimension ID card might be widely used in airport
custom, entrance of hotel, school, university, as passport for online banking, registration of on-line game, etc..

10022-21, Session 4

Digital holographic imaging and sensing
for biology and sound wave measurement(Invited Paper)
Osamu Matoba, Xiangyu Juan, Kobe Univ. (Japan);Yasuhiro Awatsuji, Kyoto Institute of Technology (Japan)
Since the invention of microscopes, countless studies andresearches have been benefited from the ever-growing
microscopic technology. However, it is still challenging tofully utilize microscopes in various field such as cell imaging.

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89

Conference 10022:
Holography, Diffractive Optics, and Applications VII
One of the difficulties is diverse information often encounter
with biological samples. It is caused by difference imaging
methods that are often incompatible. For instance, fluorescencemicroscopes only provide information of substances tagged byfluorophores. Sometimes it is necessary, and other times we wish
to obtain as many information as possible from a single object.
Since digital holographic method and fluorescence imaging
method are highly utilizable and providing different perspectives
from a single biological object, we combined the two methods in
one system to operate simultaneously. We named it multi-modal
digital microscope. The system reconstructs phase images withextensive depth of field by transmission type Mach-Zehnderinterferometry. Meanwhile, fluorescent intensity is acquired by
epifluorescence microscopic configuration. The two types ofrecording can be synced by using the same trigger.
This invited presentation introduces digital holographic
applications of bio-imaging and voice recording. We explain how
the 4D digital holographic system works. Experiments focus
on the cell reprogramming process by measuring distributionof chloroplasts from the fluorescent perspective, as well as
membranes and nucleuses from the phase perspective. In thesound wave measurement, the temporal phase imaging causedby the propagation of the sound wave is presented. Experimentresult shows the effectiveness of the proposed methods andpresents the further application.

10022-22, Session 4

Temporal speckle method for measuring
three-dimensional surface of large-sizedrough glass
Chao Li, Shanghai Institute of Optics and Fine Mechanics(China) and ShanghaiTech Univ. (China); Changhe Zhou,
ShaoQing Wang, Xin Fan, Shanghai Institute of Optics
and Fine Mechanics (China); Boquan Yang, Shanghai Univ.
(China); Yancong Lu, Shanghai Institute of Optics and Fine
Mechanics (China)
Surface measurement of large-sized rough glass is always the key
point be focused on during the production process. Traditional
3D measuring instrument like three-coordinate measurement
machine, which relies on a sharp probe to contact rough surface,and directly measures the 3D shape. So inevitably there aresome problems of it, such as low efficiency, long measurement
period and limited spatial resolution, especially for large-sizedrough glass. We propose an novel active fast 3D scanning
setup to meet the demand of fast 3D profile measurement for alarge-sized rough glass block. When it comes to rough glass, wehave to face the surface scatting problem, especially for laser
beams. In order to overcome this, band-limited binary random
pattern is introduced. Unlike the original binary random pattern,
the patterns we use are filtered out high frequency and low
frequency parts, called band-limited binary random patterns,
which proved to minimize the influence of scattering combinedwith temporal correlation technique (TCT). In our experiment,a series of N band-limited binary random patterns is used to
encode the surface of the rough glass and two cameras capture
N pairs of images strictly simultaneously as soon as each random
pattern projected. Then at matching procedure, TCT is used toreduce the size of correlation windows to one pixel in spatial
domain and extends the length of the correlation windows to N
pixel in temporal domain. Finally, by using disparities and systemparameters obtained from calibration, 3D reconstruction can beachieved. All the data acquisition process is controlled within 2s
with 0.3mm absolute error or even less.

90

SPIE Photonics Asia·

10022-44, Session Post

Holographic data storage recording
system based on computer synthesis of
Fourier holograms
Sergey S. Donchenko, Sergey B. Odinokov, Vladimir I.
Bobrinev, Alexandr U. Betin, Evgenie Y. Zlokazov, Bauman
Moscow State Technical Univ. (Russian Federation)
In this paper we present a Holographic data storage recording
device, based on computer synthesis of Fourier holograms.
Information is presented as a binary graphic information, andcalculated into grayscale Fourier hologram (CGFH). CGFH are
displayed on spatial light modulator (SLM) and projected via
optical scheme to recording medium with required reduction.
Hologram multiplexing is performed by rotation plane of 1D CGFH
relatively to recording medium. Results of recovering informationfrom holograms, recorded in Holographic data storage recording
device is presented in paper.

10022-47, Session Post

The influence of diffraction gratings relief
distortion on diffraction efficiency during
authentication security holograms
Vasily V. Kolyuchkin, Sergey B. Odinokov, Bauman Moscow
State Technical Univ. (Russian Federation); Ivan Tsyganov,Bauman Moscow State Technical University (RussianFederation)
The method of security hologram quality inspection, in which therelief phase parameters are determined by registering results of
the intensity distribution in diffraction orders, is known. Deviationof a real from the ideal profile, another words phase relief noise,
influence on the accuracy of this method. In the paper, on
the assumption of homogeneity of the phase relief noise, themathematical expressions for evaluating the influence of thephase relief noise on the intensity distribution in the diffraction
orders are represented. Parameters of the correlation functions
approximation describing the phase relief noise are determined.
The dependence of the intensity values from the standard
deviation of the phase relief noise is represented.

10022-57, Session Post

Microsphere microscopic imaging with thecoherent light
Sha Guo, Yunxin Wang, Dayong Wang, Beijing Univ. ofTechnology (China); Qiaowen Lin, Lu Rong, Beijing Univ ofTechnology (China)
The microsphere has great potential to improve the resolution ofimaging system, which can be applied in processing of surfaces
materials and detection of nano-structure etc. The high frequency
information can be collected by the microsphere; meanwhile,
the object can be magnified. The magnification varies with theparameters of the microsphere. Many experimental studies havebeen presented by combining the white light microscopy withmicrosphere and obtained the fine structure of the Blu-ray discand viruses etc. However, the curvature radius of the microsphereis from several microns to tens of microns, so the unavoidable thechromatic dispersion exists in microsphere incoherence imaging,which reduces the image quality. In this paper, the microspheremicroscopy system is designed with the coherent light, in which
the object can be magnified by microsphere and microscopy
objective (MO) twice. The polystyrene (PS) microspheres withwww.spie.org/pa·

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
the diameter of 50?m and 90?m are applied, and their refractive
index is 1.59. The object is a transmission grating with a cycle of
1.2?m separated by a gap of 500nm. The results indicate thatthe grating can be clearly detected, and the magnification of the
microsphere with diameter of 50?m and 90?m is 2.33 and 1.96
respectively. If the microsphere is absent, the resolution of thissystem is 870nm, which demonstrates that the microsphere can
improve the observed resolution from 870nm to 500nm at least.
The proposed microsphere microscopic imaging system with thecoherent light eliminates the chromatic dispersion and has thepotential application in some coherent phase-contrast imaging.

10022-58, Session Post

Generation of speckle vortices by
Archimedes’ spiral micro-holes
Haibin Sun, Shandong Normal Univ. (China) and Taishan
Univ. (China); Tingting Liu, Taishan Univ. (China); Ping Sun,
Shandong Normal Univ. (China)
Speckle plays an important role in optical field. Optical vortices
which exist in random speckle fields usually contain useful phase
information. The distribution of speckle field is determinedby these optical vortices. In order to study speckle vortices
quantitatively, we established a micro-hole array model basedon the law of Archimedes spiral arrangement. Vortex beam
can be generated by random diffuse reflection points (spiralmicro-holes), and the interference between vortex beams cangenerate speckle vortices. In the experiment, the gray imageof Archimedes’ spiral micro-holes is displayed on the screenof spatial light modulator (SLM), and the output optical fieldis captured by a CCD camera. The numerical simulations andexperimental results show that the model can be used togenerate speckle vortices.

10022-59, Session Post

Design and numerical simulation ofa silicon-based linear polarizer withmultilayer metallic nano-gratings
Yu Lin, Jingpei Hu, Chinhua Wang, Soochow Univ. (China)
With the increasing demand for linearly polarized elements withhigh performance in many fields and applications, design andfabrication of sub-wavelength metallic linear polarizer have madetremendous progress in recent years. In this paper, we proposeda novel structure of a silicon-based linear polarizer working in
the infrared (3-5?m) waveband with a multilayer metallic grating
structure. A double-layer metallic grating with a transition layerof low refractive index is fabricated on a silicon substrate. In
contrast to those conventional single layer metallic polarizing
grating, the multilayer polarizing structure has the advantagesof easy fabrication and high performance. Numerical simulation
results show that an extinction ratio of linear polarization can be
up to 60dB and the TM-polarized light transmission is greaterthan 90%. The behaviors and advantages of the proposed
multilayer polarizer are compared with that of a traditional
single-layer metallic grating in detail. The proposed silicon-based
linear polarizer will have great potential applications in realtime polarization imaging with high extinction ratio and hightransmission.

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10022-60, Session Post

Asymmetric propagation ofelectromagnetic waves through nanoscale
spirals
Jingpei Hu, Yu Lin, Xiaonan Zhao, Aijiao Zhu, Chinhua
Wang, Soochow Univ. (China)
Polarization not only represents an intrinsic feature of opticalwaves but also offers an extra degree of freedom to manipulate
light for various applications. In particular, circularly polarized
light has its instant electric field vector directed along a helicaltrajectory and therefore possesses an inherently chiral nature.
Recently, archimedes spiral designs have been utilized to beminiature circular polarization analyzer. S. Yang et al. studied
Archimedes’ spiral groove etched into a gold film can focuses
the circular polarization with an opposite chirality into a solid
spot in the center, while defocusing the circular polarization
with the same chirality into a donut shape. In 2015, S. Grisha etal. designed and implementation of a metasurface-based spiralplasmonic lens that achieves both optimized SPP focusing
and high-contrast, large-collection-area circularly dichroic
focusing. However, the spiral structures can only distinguish the
CPL in mode, not the transmission intensity. In this paper, we
report that normal incidence transmission of different circularly
polarized waves through the 2D Archimedes’ nanoscale spirals
is asymmetric. The structures consist of raised spiral line andtwo layers metal film covered on the substrate and the line.
The device can distinguish the different circularly polarizedwave across the transmission intensity compare with thecommom Archimedes’ nanoscale spirals which just exhibit thebright or dark modes in the light field. We confirmed that thedevice provide about 10% circular dichroism in 3.85um-6.0um
broadband region. The circular dichroism in the wavelength
3.95 um can reach 13%. This ultracompact device could prove
useful for remote sensing and advanced telecommunication
applications.

10022-61, Session Post

High resolution digital holography basedon the point source scanning
Minchao Wang, Dayong Wang, Lu Rong, Yunxin Wang,
Fengpeng Wang, Qiaowen Lin, Beijing Univ. of Technology(China)Digital holographic microscopy has been widely used for theimaging of micro-objects and biological samples. Lensless in-line
digital holographic microscopy is capable of wide field-of-view
imaging, however the spatial resolution of the reconstructed
images is limited by the pixel size of the detector. The relative
position shift between the sample and the detector caneffectively improve the resolution in the traditional sub-pixel
shifting method, but it requires a high precision of translation
stage. Therefore to overcome this problem we propose a method
based on the point source scanning to realize sub-pixel shifting,where by using the geometric relations between point sourceand detector, high precision sub-pixel shifting is achieved easily.
Through moving the point source, multiple holograms with
sub-pixel shifts are captured which are merged together toobtained a hologram by using the synthesizing algorithm, thena phase retrieval algorithm is used to reconstruct the phaseand amplitude distributions of the object. Using 1951 USAF
resolution test target as object, we effectively recover a muchhigher resolution as compared to traditional digital hologram,which is no longer limited by the pixel size of the detector. The
feasibility of the proposed method is demonstrated by simulationand experiments. The proposed method has the advantages ofsimple recording setup and lower precision requirement of the#PhotonicsAsia

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
of Fresnel CGH and Fourier CGH in MATLAB. Secondly, it isolates
the original image and the conjugate image in regeneration of
Fourier CGH by using grater than image coding with matrix of all
zero matrix. Even though the original image and the conjugate
image can be separated, the two of them also prevent us toacquire the original message. For reserving the most valuable
message, we could apply the window function to filter one ofthem. Finally, in the coding of Fourier and Fresnel CGH, this paper
describes several functions to decrease the noise that the original
image is encoded into program. The functions can be available in
Fourier CGH and Fresnel CGH. The simulated result demonstrates
the proposed method has high applicability. This method ofcoding have the potential for applications in encryption.

translation stage. It can obtain the wide field-of-view and highresolution imaging.

10022-62, Session Post

Experimental study of the methodof recording color volume security
holograms on different photosensitive
materials on the base of the diffuser witha narrow indicatrix of laser radiation
Dmitry S. Lushnikov, Sergey B. Odinokov, Vladimir V.
Markin, Alexander Y. Zherdev, Bauman Moscow State
Technical Univ. (Russian Federation); Andrey V. Smirnov,
Krypten (Russian Federation)

10022-64, Session Post

The objective of this paper was to obtain a new type of security
holograms - multicolored holographic stereograms with different
security elements on the photosensitive medium of large
thickness. During work performance the following problems havebeen solved:
1. Reducing the production time of color holograms asholographic stereograms.
2. Improve the quality of images reconstructed from holographic
stereograms.
The work has been divided into the following stages:
1. One-parallax and full-parallax holographic stereograms
production by using one-step and two-step schemes with adiffuser with wide emission indicatrix in a subject branch. Quality
analysis of the obtained holograms.
2. Full-parallax holographic stereograms production by using
two-step schemes without a diffuser in a subject branch. Quality
analysis of the obtained holograms.
3. Production of the holographic diffusor with narrow emission
indicatrix.
4. Full-parallax holographic stereograms production by using
two-step schemes with a diffuser with narrow emission indicatrix
in a subject branch. Quality analysis of the obtained holograms.
All these schemes and holograms were obtained and analyzed.
The disadvantages of schemes without a diffuser are shown inthis article. The scheme for recording of holographic stereograms
using a holographic diffuser with a narrow indicatrix has beendeveloped and described in the article. The high quality ofimages reconstructed from these holographic stereograms areshown. The time of recording such holographic stereograms was
3..5 hours.

10022-63, Session Post

Realization of Fourier and Fresnel
computer-gengerated holography basedon MATLAB
Computer-generated hologram(CGH) could be widely used.
The image, which could be considered the original object oftraditional optics, can be divided into two parts. A portion of itis encoded into Fourier CGH, while the remaining is coded into
Fresnel computer generated hologram. Hence, in the processingof message transmission, the possibility of information being
stolen can be greatly reduced. When the image is coded into the
Fourier CGH and Fresnel CGH, and reached the receiving end,
the original image could be obtained by the reconstruction of the
two CGH. This paper presents three important points. Firstly, it
provides the recording and reconstruction of the source program

SPIE Photonics Asia·

Bilali Muhutijiang, Xinjiang Normal Univ. (China); Keqiang
Qiu, Univ. of Science and Technology of China (China);
Taximaiti Yusufu, Xinjiang Normal Univ. (China)
The chirped-pulse amplification system plays a critical role in
the process of achieving high-peak ultrashort pulses. Chirpedpulse amplification technology performance mainly depends
on the pulse compression gratings. Diffraction efficiency isthe critical parameter of the pulse compression gratings, andoptimization of grating shape can achieve higher diffraction
efficiency. If the photoresist grating mask bottom is not clean,
the side walls would not be steep and duty cycle would be too
big or too small, thus multi-layer dielectric grating diffraction
efficiency would decrease. Solving these problems is the key
to improve the diffraction efficiency. In this paper, ashing andoxygen etching methods are used to reduce the photoresist mask
duty cycle, and PDMS pressing method is used to increase theduty cycle of photoresist mask, and aperture up to 100 mm?100
mm. Best photoresist grating mask parameter could be obtainedby effectively combining the above two methods. Based on
above techniques, a number of pulse compression gratings withline densities of 1740 lines?mm was achieved. The diffraction
efficiency at the-1st order was greater than 99% for TE polarized
light. A qualitative judgments for graphic transfer of ion beametching is received through the picture before and after etchingwhich is get from the SEM. These experimental results proved theaccuracy, stability, and success rates of the technique.

10022-65, Session Post

Broadband Plasmonic Metasurfaceenabled Quarter Waveplates with Fencetype Grating
Aijiao Zhu, Jingpei Hu, Chinhua Wang, Soochow Univ.
(China)Guoqiang Lin, Xuechang Ren, Xiamen Univ. (China)

92

Improve the diffraction efficiency of themultilayer dielectric gratings

Metasurface-enabled waveplates have attracted considerable
attentions. Optical metamaterials consist of subwavelength
plasmonic building blocks arranged in two-dimensional
arrays. Compared to conventional bulky waveplates made ofbirefringent optical crystals, two-dimensional metasurfaces
have comparable ability to enhance electromagnetic fields andcontrol light polarization while in an ultrathin, planar platform,
making them attractive for optical system miniaturization andintegration. Metasurface-enabled waveplates typically utilized
arrays of anisotropic resonant building blocks, such as crossed
nanoslits, L-shaped or V-shaped nanoantennas, and so on,which often suffer from narrow bandwidth. Broadband andhigh-performance polarization conversion is in urgent needat this time. Recent years, rod-shaped, metallic nanoantennas

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
demonstrated to have strong, localized, plasmonic resonances
are utilized to control polarization. A broadband opticalmeta-waveplate operating at the near-infrared regime in thetransmission mode has been proposed using plasmonic nanorods
with two orthogonally coupled nanodipole elements. Here we
report a metasurface consisted of cross-shaped Ag nanorods
to make a high-performance quarter waveplate with extreme
bandwidths in the near-to-mid infrared. We tune the wavelengthof plasmonic resonance and the magnitude together withthe phase of polarization of the nanorods by engineering thegeometric dimensions of them. The quarter waveplate is realizedby optimizing the anisotropic response of the metasurface via
changing the sizes of the arms of the crosses. Compared topreviously reported metasurface-enabled waveplates, the phaseretardation of the electric component of the transmitted wave
is exactly equal to ?/2 across a broad wavelength range rather
than merely near the resonant wavelength of the metasurfacebuilding blocks. Simulation results indicate that the polarization
conversion can be realized in the near-to-mid infrared. In
addition, a wavelength-dependent electric field polarization
direction was required for the incident linearly polarized lightin this structure.Our work gives intriguing possibilities for novel
metasurface-enabled optical components with broad operational
bandwidth for photonics devices.

10022-67, Session Post

Virtual viewpoint generation for threedimensional display based on thecompressive light field
Qiao Meng, Xinzhu Sang, Duo Chen, Nan Guo,
Binbin Yan, Chongxiu Yu, Beijing Univ. of Posts andTelecommunications (China); Wenhua Dou, Liquan Xiao,
National Univ. of Defense Technology (China)
Virtual view-point generation is one of the key technologies thethree-dimensional (3D) display?which renders the new scene
image perspective with the existing viewpoints. The threedimensional scene information can be effectively recoveredat different viewing angles to allow users to switch between
different views. However, in the process of multiple viewpoints
matching, when N free viewpoints are received, we need tomatch N viewpoints each other, namely matching CN2=(N(N-1))/2
times, and even in the process of matching different baselines
errors can occur. To address the problem of great complexityof the traditional virtual view point generation process, a noveland rapid virtual view point generation algorithm is presented
in this paper, and actual light field information is used rather
than the geometric information. Moreover, for better making
the data actual meaning, we mainly use nonnegative tensor
factorization(NTF). A tensor representation is introduced for
virtual multilayer displays. The light field emitted by an N-layer,
M-frame display is represented by a sparse set of non-zeroelements restricted to a plane within an Nth-order, rank-M tensor.
The tensor representation allows for optimal decomposition ofa light field into time-multiplexed, light-attenuating layers using
NTF. Finally, the compressive light field of multilayer displays
information synthesis is used to obtain virtual view-point by
multiple multiplication. Experimental results show that theapproach not only the original light field is restored with the highimage quality, whose PSNR is 25.6772dB, but also the deficiencyof traditional matching is made up and any viewpoint canobtained from N free viewpoints.

10022-68, Session Post

Software adaptation requirements
identification based on space light
modulate
Hua Liu, Science and Technology on Electro-optic Control
Lab. (China)
The development of space-time adaptive system is based on theadaptation requirements identification and analysis. It clarifies
what changes the software and hardware will face during
operation and how it needs to deal with them. In space-time
adaptive system requirements analysis and system modeling, theadaptive spatial light modulation control software is based on theneeds of identification and the analysis of real applications,which
will be considered a software of the control object. From theenvironmental awareness and sense of two kinds of feedback
mechanism of demand, it will to identify and analyze theadaptability of software/hardware system requirements. Basedon spatial light modulation theory, the core photoelectric
information control system is explored to build in the complex
environment, and to realize the space-time adaptive systemframework which satisfy the requirements for construction
and operation support. An example is used to demonstrate thefeasibility of the proposed approach.

10022-69, Session Post

Characteristics of the autostereoscopic
three-dimensional LED display based on
diffractive optical elements sheet
Ping Su, Graduate School at Shenzhen, Tsinghua Univ.
(China); Pengli An, Jianshe Ma, Shu An, Liangcai Cao,
Tsinghua Univ. (China)
The autostereoscopic LED display (ALEDD) using diffractive
optical elements sheet as light steering element has been
proposed recently in order to obtain thinner display panel andachieve a better 3D perception. Research on the characteristicof the ALEDD using DOEs sheet is of prime importance to thewidely application of the ALEDD.
In this paper, the effects caused by the assembling errors
between the LED display and DOEs sheet are theoreticallyanalyzed. The mathematical model of the relationship of thedisplay parameters and the 3D display effect is built. Based on
the model, the impact of errors of the parameters on the 3D
display effect is analyzed. An adjusting device fixed onto the
DOEs sheet with 6 degrees of freedom is implemented, andthe impact of the deviations along every direction on the 3D
display effect is studied experimentally. The results show that,the tolerance assembling errors are |?z|≤1mm, and |??x, ??y|≤1°,
respectively. This conclusion will benefit a lot in instructing
the installation of the autostereoscopic three-dimensional LED
display system to reduce the crosstalk and improve the quality of
3D perception. The methodology of this paper also can be usedin most kinds of autostereoscopic displays.

10022-70, Session Post

Experiments of diffractive opticalelements obtained by ion plasma etchingfor aiming and display devices
Sergey B. Odinokov, Hike Sagatelyan, Artem
Solomashenko, Yanina Grad, Polina Malinina, Bauman
Moscow State Technical Univ. (Russian Federation)

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
Diffractive optical elements (DOEs) are used in the information,
aiming and display systems, where the observed signs-symbolic
information is superimposed on the real scene. The use of aiming
and display devices in different climatic conditions requires theprotection of the photosensitive layer. These elements may need
to be physically protected or recorded directly into the glass.
Method of their design and fabrication based on ion plasma
etching are described. The optimal parameters of period andrelief depth are defined and experimental results of DOEs arepresented. These results show that the DOEs obtained by ion
plasma etching can be applied in display systems used in difficult
climatic conditions.

10022-71, Session Post

Tunable nanostructure generation using asurface plasmon resonant cavity
Fuyang Xu, Zhejiang Normal Univ. (China); Chinhua Wang,
Davis Lou, Soochow Univ. (China)
With the developments of the nanoscale science and technology,
the breakthrough of optical diffraction limit has become asignificant issue in lithography. And the phenomena of surface
plasmon polaritons (SPPs) provides another promising approachto achieve sub-diffraction limit nano-patterning.In this paper, we
report a tunable two-dimensional (2D) dot array nanostructure
generation using a metal-insulator-metal (MIM) surface plasmon
resonant cavity formed by top silver layer, photoresist layer andbottom silver layer. Theoretical analysis and numerical simulation
results show that the period of the 2D dot array can be tuned
to generate ultra-deep subwavelength patterns by varying thecavity length with a fixed 2D diffraction-limited mask, and theexposure depth can be extended to the entire cavity. It may
provide a flexible photolithography technique with capability oflarge area, tunable period and deep exposure depth.

10022-72, Session Post

Decoupling refractive index and geometricthickness based on dual-wavelength
digital holography
Weining Chi, Dayong Wang, Lu Rong, Yunxin Wang,
Fengpeng Wang, Beijing Univ. of Technology (China)
The information of phase distribution of an object is a key tocalculate its geometric thickness and index of refraction. Digitalholography has the advantages of three dimensional imaging,
non-contact and flexible digital processing, it has been widelyused in the fields of biomedicine, material sciences and so on.
The phase information of the sample, which is proportional to
the refractive index and thickness, can be obtained by digitalholography. Quantitative phase imaging techniques (QPM) basedon dual-wavelength digital holography has been presented,
which in principle can accurately measure the refractive index
and thickness information of the transparent sample at a given
wavelength by using decoupling algorithm, without priorknowledge of their respective parameters. In this paper, the premagnified digital holographic microscopy setup based on MachZehnder interferometer is used to recording two holograms withtwo different wavelengths respectively. Different wavelengthsof light causes different optical-path-differences (OPD) when
it passes through the transparent samples or the reference
medium, as a result the reconstructed phase distribution of twoholograms is different. The phase distribution of each wavelength
is reconstructed by fast Fourier transform and spectrum filtering
algorithm which is later use to calculate the refractive index
and thickness of the samples by decoupling algorithm. The
experimental system is greatly simplified by using the tunable
laser which provides the opportunity to choose more than one
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SPIE Photonics Asia·

wavelength in order to improve the accuracy of experimental
results. Simulation and experimental results are presented
to demonstrate the feasibility of suggested method with thedecoupling algorithm.

10022-73, Session Post

The measurement of flow speed of onchip micro-fluid by digital holography
Yutong Cui, Zhe Wang, Chan Sun, Zhuqing Jiang, Beijing
Univ. of Technology (China)
In most of the measurement and analysis in liquid, flow speedof the fluid is one of the important parameters, especially in
microfluidic chip imaging. Some published papers point out
that the change of flow rate may be related to the change ofphase information of the fluid. The behavior of micro-fluids ona microfluidic chip is different from common fluidic’ behavior
in that factors such as surface tension, energy dissipation, andfluidic resistance. The flow speed as a basic parameter may be
detected via retrieval of phase information in the fluid. Digitalholographic microscopy is an effective imaging technique that
employs a CCD camera to record holograms and a numericalsimulation diffraction process to achieve imaging reconstructionof one object. In this paper, a method to measure the flow speed
based on microfluidic chip by digital holography in real-time
is presented. The injection pressure of microfluidic device ischanged to create different flow speed in microfluidic channels.
On this basis, the phase distributions within the microfluidic
channels can be reconstructed by using digital holographic
microscopy, and then, the relationship between the fluidic
phase and flow speed could be obtain by measuring the phase
distributions of cross section. In the experiments, the several
liquids of the different concentrations are used to demonstrate
the fluidic speed measurement. In addition, the chip calibration ismade to ensure the validity of the experimental results.

10022-74, Session Post

Real-time measurement of liquid
concentration changing by digitalholography
Chan Sun, Zhe Wang, Yutong Cui, Zhuqing Jiang, Beijing
Univ. of Technology (China)
The microfluidic technology has been widely used in the fieldof biochemical analysis, disease diagnosis, minimally invasive
surgery and environment monitoring. The measurement ofsolution concentration as one of important characteristics
parameters is commonly required, particularly, in the caseof the real time variation of the solution concentration in the
microfluidic system. Digital holography is a high-resolution
imaging technique that employs the CCD as a recording device
and a numerical simulation diffraction process to achieve
amplitude and phase imaging reconstruction of an object. The
digital holographic imaging typically consists of the proceduresof holographic recording and phase reconstruction from therecorded holograms. As we known, the change of refractive index
of a liquid could be related to its phase distribution, and thechange of solution concentration could result in the increase or
decrease of refractive index. Thus, the variation and distributionof solution concentration can be described via its phase image
reconstructed by digital holography. In this paper, a methodof real-time measurement of liquid concentration changing in
Y-type microfluidic chip by digital holography is presented. In
the experiments, salt solutions of different concentrations are
injected into the two channels of the Y-type microfluidic chip asa target object, and then the refractive index of the target canbe yielded from the reconstructed phase image. The experimentwww.spie.org/pa·

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
results show that the real-time changing of liquid concentrationin microfluidic chip can be effectively measured by digitalholographic microscopy.

10022-75, Session Post

A novel three-dimensional display system
based on integral imaging using lightshaping diffusor
Xiaoyu Jiang, Zhiqiang Yan, Xingpeng Yan, Jian Su, Hui
Gao, Academy of Armored Force Engineering (China)
Integral imaging is known as a promising 3D display method for
its ability to reconstruct the light field of the scene. However,integral imaging suffers from low spatial resolution and narrowviewing angle due to the limited spatial bandwidth product of
LCD, which prevents its commercial application. In conventional
integral imaging display, spatial resolution and viewing angle are
two conflicting factors, and previous research mainly focuseson the compromise of the two factors. A novel integral imaging
3D display system with large viewing angle (about 40°) andhigh spatial resolution for HVS is presented. The system iscomposed of a high definition 4K LCD, a macro lens array anda light shaping diffusor. One point of the system different fromconventional integral imaging in which micro lens array is used, amacro lens array (with elemental lens diameter 1cm) is employedin our system to ensure a large viewing angle, however, this may
result in low spatial resolution for HVS. And the other point isa light shaping diffusor is placed in front of the lens array withproper distance, and lifelike 3D reconstruction is obtained. The
context is organized as follows: Firstly, the principle of the system
is explained; Secondly, the configuration and design of thesystem are depicted, also the spatial resolution and viewing angle
are analyzed; Finally, experimental results with full parallax, large
viewing angle and high resolution 3D images are shown to verify
the validity of the proposed system.

Analysis of performance of the direct
search with random trajectory method
applied to the task of minimization of
kinoform synthesis error
Vitaly V. Krasnov, National Research Nuclear Univ. MEPhI(Russian Federation)
Synthesis of diffractive optical elements is one of the vitaltasks of computer optics. Diffractive optical elements (DOE)
are widely used in different areas of science and technology.
Among different kinds of DOE, kinoforms are most effective formany applications. Kinoform is synthesized phase DOE whichallows to reconstruct image by its illumination with plane wave
similarly to hologram. Unlike hologram however, kinoform forms
only one diffraction order containing reconstructed image.
Thus, kinoform has maximum theoretical diffraction efficiency.
Kinoforms are generally used as focusers, wavefront correctors,
optical switches and transducers in image processing systems.
There is no analytical solution to kinoform synthesis problem,
therefore various iterative methods providing relatively small
synthesis error are used. However, with restrictions on quantityof addressable phase levels this error becomes significant. Direct
search with random trajectory (DSRT) method applied to thetask of minimization of kinoform synthesis error is similar to
direct binary search method for binary holograms synthesis. Maindifference is that the used method is designed to process arrayswith multiple phase levels. Synthesis procedure is described asfollows. First, kinoform is generated with conventional method
such as Gerchberg-Saxton. Then, elements of kinoform aresequentially switched to obtain lower synthesis error value. This
process goes on until minimum error value is reached. Analysis
of performance of the DSRT method depending on kinoform size
and number of phase levels is conducted. Results of numericalexperiments are presented.

10022-78, Session Post

10022-76, Session Post

Generation and representation of vector
vortex beams based on metasurfaces
Xunong Yi, Hubei Engineering Univ. (China)
Metasurfaces can be regarded as a class of metamaterials
with a reduced dimensionality. In this work, we present a
method for generating vector vortex beams with metasurfaces.
The metasufaces are designed based on space-varying
Pancharatnam-Berry geometric phase. A Jones calculation is
employed to theoretically analyze the phase and polarizationtransformation from metasurfaces. The experimental results areshown to agree well with the theoretical expectation. Lastly, asa geometrical representation, the hybrid-order Poincaré sphereis proposed to describe the evolution of polarization states oflight wave propagating in metasurfaces. Using the hybrid-order
Poincaré sphere, we can conveniently obtain the polarization
evolution in metasurfaces with special geometry. Similar to thepreviously proposed Poincaré sphere, the hybrid-order Poincaré
sphere can intuitively demonstrate the Pancharatnam-Berryphase due to the change of polarization state. So the hybridorder Poincaré sphere can also become an effective tool toprovide help in designing metasurfaces. Our research deepens
the understanding on the manipulation of polarization and phase
based on Pancharatnam-Berry phase and offer an alternative
method for generating vector vortex beams.

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10022-77, Session Post

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Numerical comparison of scalar and vector
methods of digital hologram compression
Pavel A. Cheremkhin, Ekaterina A. Kurbatova, National
Research Nuclear Univ. MEPhI (Russian Federation)
Digital holography allows reconstruction of amplitude and phase
3D-scenes. For this interference pattern should be formed,
registered by the digital camera and then processed. Currently
images files sizes are equal to tens megabytes. For transfer ofholographic video with movies standard frequency, channel
with capacity of 2-4 Gbit/sec should be used. 10 minutes ofholographic video is more than 1 terabyte. Thus large memory
volumes are required to store holographic video. For speed upof holograms transmission and memory volumes reducing, it ispossible to compress holograms. Compression of the holographic
data is important in different tasks: security systems, registrationof micro and macro objects, tomography, and etc. Standard
methods of compression of digital images (for example, JPEG)
can be used for holograms. However they are less applicabledue to the various facts: intensity sharp changes in holograms
images; holographic registration not only amplitude, but also
phase of wave; and etc. Therefore other types of methods ofholograms compression and quantization were analyzed: scalarand vector ones. In this paper 4 common scalar and vector
methods of holograms compression are considered. Experimentsof compression of digital holograms were numerically carriedout. Two scalar methods were used: nonuniform logarithmic anduniform quantization. Two vector methods were investigated:k-means and k-medians clustering. Compression of hologram file
was achieved primarily by decreasing of hologram quantization#PhotonicsAsia

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Conference 10022:
Holography, Diffractive Optics, and Applications VII

10022-81, Session Postlevels quantity. Quality of objects reconstruction by mentioned
methods, diffraction efficiency and computational resourceswere compared. Dependencies of these values on quantity ofhologram quantization levels are plotted.

A three-dimensional content remapping
method for the auto-stereoscopic display
Can Cui, Xinzhu Sang, Peng Wang, Duo Chen, Nan
Guo, Binbin Yan, Kuiru Wang, Beijing Univ. of Posts andTelecommunications (China); Liquan Xiao, National Univ.
of Defense Technology (China)

10022-79, Session Post

High linearly polarized white-lightemission from LEDs with multilayer
dielectric/metal wire-grid structure
Linghua Chen, Chinhua Wang, Soochow Univ. (China)
We proposed and experimentally demonstrated a linearlypolarized white light from InGaN light-emitting diode with
nano-gratings integrated fluorescent ceramics. By incorporatinga dielectric layer of low refractive index between multilayer
nano-gratings and a fluorescent ceramics of high refractive index,
both high TM transmission (TMT) and high ER can be effectively
achieved across the whole range of white light. An extinction
ratio of higher than 20dB and TMT of 60% were obtained
experimentally for a GaN/fluorescent ceramics integrated white
LED (450nm-650nm) with a multilayer grating of 150nm period.
The fluorescent ceramics integrated structure shows possibilities
of implementing polarized white light LED in a fashion ofcompact, long-life and high performance.

10022-80, Session Post

Optimization design and laser damage
threshold analysis of pulse compression
gratings

10022-84, Session Post

Shuwei Fan, Liang Bai, Nana Chen, Xi’an Jiaotong Univ.
(China)As a milestone in the development of laser technique,chirp pulse
amplification(CPA) technique is widely applid to produce ultrahigh power laser.Pulse compression gratings (PCG),one of CPA
core components, is becoming hot topic. Multilayer dielectric
gratings(MDG) and mixed metal dielectric grating(MMDG),with higher damage threshold(LDT) and higher diffraction
efficiency(DE) compared with metal grating, are gradually used
as compression gratings. Paper’s main work about MDG and
MMDG is as follows:Firstl, thin-film structure with high reflectance, which would
be applied to MDG and MMDG, was designed by combining
characteristic matrix method and global optimization algorithm.
The reflectance of the thin-film was closed to 100% after being
optimized, and the bandwidth was over 200nm.
Second, grating optimization design software based on vector
rigorous coupled-wave and generic algorithm was developed.
The optimization design of MDG and MMDG was studied, which
demonstrated that the highest diffraction efficiency was over
99% and bandwidth of MMDG was to over 200nm, 50nm wider
than that of MDG.
Third, the study on laser damage threshold of thin-film structure
was done by discussing the internal electric field distribution of
the thin-film. With the help of Matlab, the simulation softwareof standing wave field distribution within MDG and MMDG
was developed. The standing wave field of MMDG with threedifferent reflective thin- film structure was calculated. And the
key parameters which affected the electric field distribution werestudied with the aid of the software.

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Generally, there is a depth of field (DOF) constraint for eachkind of auto-stereoscopic display owing to the limited angularresolution, which restricts the depth of display. Device-specificblurring will occur if the depth of object exceeds the DOF
boundary. A novel depth-perception preserved three-dimensional(3D) content remapping method is presented to meet the DOF
constraint of a target 3D display, by using a nonlinear global
operation followed with local depth contrast recovery. Apparent
depth is dominated by the distribution of depth contrast rather
than an absolute depth value. The framework can be divided
into two steps. Firstly, a nonlinear operation is adopted to remap
the reference depth map of image to fit into the DOF limitation.
Secondly, the depth contrast is recovered by decomposing thereference and remapped depth map into multi-frequency bands,
calculating the difference for each band, and then the remapped
depth map is used to add the scaled difference of depth mapof top levels’ frequency bands. A warping-based view synthesis
method is adopted to retarget the light field according to themodified depth map. The experimental results show that themodified light field is sharp while the original perception of depth
is maximally preserved.

Phase extracting and unwrapping
algorithm of electrical speckle shearing
phase-shifting pattern interferometry
Chao Jing, Ping Zhou, Beijing Institute of Environmental
Features (China)
Electrical Speckle Shearing Phase-shifting Pattern Interferometry(ESSPPI) has been used in the fields of non destructive testing(NDT) and stress field analysis as a precise deformation
measuring method. The general fixed-step phase extracting
algorithms of ESSPPI, such as three-step algorithms, four-stepalgorithms, five-step algorithms, and their corresponding errors
are analyzed. It is proved that the phase accuracy of ESSPPIwith different algorithms are mainly affected by linear error ofphase-shifting. Therefore the modified four-step phase-shifting
extracting algorithm that isn’t sensitive to linear error of phaseshifting is adopted in the paper. The filtering algorithm should be
employed to reduce the influences of speckle noise and wrong
data caused by errors during measurement. Then the leastsquares phase-unwrapping algorithm based on fast discretecosine transform (LPABFDCT) is adopted to search the leastsquares solutions between phase difference value of adjacentpixels and unwrapping phase difference value of the pixel andthe real phase distribution caused by object deformation is
obtained. The Electrical Speckle Shearing Phase-shifting Pattern
Interferometric images are captured with four-step phase-shifting
method and the real phase distributing image is achieved withmodified four-step phase-shifting extracting algorithm, denoisingfilter and the least-squares phase-unwrapping algorithm basedon fast discrete cosine transform. It is proved with experimentresults that the real phase distributing images are effective
achieved by mean of combination of average filter and the leastsquares phase-unwrapping algorithm based on fast discretecosine transform.

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Conference 10022:
Holography, Diffractive Optics, and Applications VII

10022-85, Session Post

Boundary perturbation solution of thecircular hollow waveguide
Xue Qin, Yan Wang, Xiaoyan Wang, Xiaona Yan, Huifang
Zhang, Lihua Bai, Shanghai Univ. (China)
A method based on the perturbation of the boundary conditions
on the metallic walls of the waveguide is used for computing
the propagation constant. This method is more direct, effective
and quicker than obtaining the propagation constant from thecharacteristic equation. The expression of propagation constant
includes both the real part and imaginary part. There is a good
agreement between this expression and the result of numericalsimulation from the COMSOL Multiphysics. The result showsthat the HE11 is the perturbation of the TE11, we can obtain
the expression of the HE11 propagation constant relies on the
distribution of the TE11. Moreover, the propagation constant isstudied for the single-mode transmission and the multi-mode wehaven’t considered.

10022-86, Session Post

Experimental study on degree of
coherence for stochastic electromagnetic
fieldsJuan Zhao, Heriot-Watt Univ. (United Kingdom) andSuperD Co., Ltd. (China); Mitsuo Takeda, Utsunomiya Univ.
(Japan); Wei Wang, Heriot-Watt Univ. (United Kingdom)
All optical fields undergo random fluctuation and the degreeof coherence defined as the normalized correlation functionof optical fields has played a fundamental role as an important
manifestation of the underlying random fluctuations. For
randomly varying electromagnetic waves, the usual treatmentof polarization based on the well-known Stokes parametersor polarization matrices is not adequate and a unified theoryof coherence and polarization of random electromagnetic
beams has been proposed by Wolf to elucidate the changes ofpolarization and coherence as the beam propagate.
In this paper, a novel optical geometry is proposed based on thepolar-interference law of electromagnetic beams with its uniquecapability to visualize the mutual coherence tensor directly. Notethe fact that wave equations govern the propagation of mutual
coherence tensor, which can be regarded as a tensor wave.
After retrieval of the complex functions for all the elements ofcoherence tensor from the recorded interferograms, we obtainthe magnitude and the unit direction tensor for the coherence
tensor wave and demonstrate the degree of coherence forstochastic electromagnetic fields with partial polarization andpartial coherence experimentally for the first time.

10022-88, Session Post

Bilayer metasurface for asymmetricpolarization conversion for transmission
and reflection
Joonsoo Kim, Hyeonsoo Park, Byoungho Lee, Seoul
National Univ. (Korea, Republic of)Metasurfaces refer to two-dimensional array of subwavelengthsized nano-antennas which can be designed to manipulate
amplitude and phase of scattered light. Due to their abilities
to control wavefronts, polarization distributions of opticalfields and potential applicability to ultrathin, high numericalaperture optical components, metasurfaces have been attracting

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attention of many researchers. Particularly, there have been
efforts to enhance functionality of individual metasurface
cells by exploiting various degrees of freedom in the nanoantenna design. For instance, various schemes for polarization
multiplexing and a metasurface for simultaneous control ofphase and polarization have been reported. Actually, asymmetrictransmission/reflection characteristics are closely related tomultiplexing since multiplexing can be achieved by combining
the asymmetric scattering behaviors. In the case of polarization
multiplexing, asymmetry in the polarization conversion for two
polarization inputs plays a central role. Similarly, asymmetryin transmittance and reflectance for cross-polarization can be
exploited for two-side multiplexing of metasurfaces.
In this paper, we propose a bilayer metasurface structure withtransmission/reflection asymmetry. We assume that the proposed
metasurface is embedded in homogeneous dielectric medium toensure that the reflection asymmetry is not originated from thesubstrate effect. Firstly, we design a two ultrathin metasurfaces
one of which consists of polarization-sensitive nanoslit antennas
and the other one consists of polarization-insensitive apertures ina way that maximizes the transmission. Then, we cascade the two
surfaces with a thin dielectric gap and observe the transmittance/
reflectance ratio for varying gap thicknesses and antenna
dimensions. The proposed structure is expected to be used fordevelopment of transflective metasurfaces.

10022-89, Session Post

3D polarisation speckle as ademonstration of tensor version of thevan Cittert-Zernike theorem for stochastic
electromagnetic beams
Ning Ma, Juan Zhao, Heriot-Watt Univ. (United Kingdom);
Steen Grüner Hanson, DTU Fotonik (Denmark); Mitsuo
Takeda, Utsunomiya Univ. (Japan); Wei Wang, Heriot-Watt
Univ. (United Kingdom)
Laser speckle has received extensive studies of its basic
properties and associated applications. In the majority of
research on speckle phenomena, these random optical fields
have been treated as scalar optical fields, and the main interest
has been in the statistical properties and applications of theintensity distribution of the speckle patterns. Recently, statisticalproperties of random electric vector fields referred to as
Polarization Speckle have come to attract new interest becauseof their importance in a variety of areas for practical applications
such as biomedical optics and optical metrology. Statisticalphenomena of random electric vector fields have close relevanceto the theories of speckles, polarization and coherence theory.
In this paper, we investigate the correlation tensor for stochastic
electromagnetic fields modulated by a depolarizer consisting ofa rough-surfaced retardation plate. Under the assumption thatthe microstructure of the scattering surface on the depolarizer
is as fine as to be unresolvable in our observation region, we
have derived a relationship between the polarization matrix/
coherency matrix for the modulated electric fields behind therough-surfaced retardation place and the coherence matrix
for free space geometry. This relation may be regarded as
entirely analogous to the van Cittert-Zernike theorem ofclassical coherence theory. Within the paraxial approximation
as represented by ABCD-matrix theory, the three-dimensionalpolarization speckle has been investigated from the correlation
tensor for the generated polarization speckle, indicating a typicalspindle structure with a much longer axial dimension than theextent in its transverse dimension.

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Conference 10022:
Holography, Diffractive Optics, and Applications VII

10022-90, Session Post

10022-92, Session Post

Space telescope using laser beamholography for interferometric image
construction using telescopic apparatus
for celestial objects, space, and also for
construction and spatial mapping, remotesensing in other planets in base plate andother materials, and monitoring devices

Temperature sensor based on Fano andLorentzian resonance lineshapes of aphotonic crystal cavity

Mohammad M. Anwar, Forever Living Products(Bangladesh)
The celestial objects can be visible using any telescope and we
can take the object picture with a telescope and then illuminatethat using laser beam and make a holographic image for thatthat can be seen on the holographic recording device or in any
monitoring device .We may use the holographic apparatus inconnection with any telescope for doing regular holographic
image with the objective lens of the telescope to visualize any
celestial object image like any planets , star, or any planetary
surface or any object studying there , for mapping or remotesensing and also many other purposes for exploring space andcelestial objects even for making 3D map for asteroid belts andits component .The basic instrument may have the same basic
principle as that for producing holography like interference
production from reference beam and scattered beam , but
we can use more complicated things for phase matching andproperly tuning the image very clear using computer softwareand also other technique in geometrical optics.
Introduction:

10022-91, Session Post

Autofocusing through cosine and modified
cosine score in digital holography

Chenyang Zhao, Xuetao Gan, Qingchen Yuan, Jianlin Zhao,
Northwestern Polytechnical University (China)
So far, the well-developed optical temperature sensors are fiberoptic sensors due to the high sensitivity and easy fabrication.
However, they can hardly be used in integrated chips, limiting
their applications in the fields of micro-optoelectronics.
Compared with optical fiber based temperature sensors, silicon
photonic sensors can achieve much higher sensitivity due tothe high thermo-optic coefficient and compatible with thecomplementary metal-oxide-semiconductor (COMS) fabrication
process. Photonic crystal (PC) cavities, as one of the importantchip-integrated photonic architectures, enable the control of lightpropagation and interaction with matter in wavelength-scale.
Using the character of high quality (Q) factors and strong field
confinement, PC cavity can be designed as a sensor to detect the
local index changes in their environment.
We report an ultra-small temperature sensor based on silicon
PC cavity, which employs two resonance line shapes of thecavity, i.e., high Q factor Lorentzian resonance line shape andsharp asymmetric Fano resonance line shape. To achieve thesensitivity with different temperature, the temperature variationis measured by monitoring the shift of the resonant wavelengthand the variations of transmitted intensity in the PC cavity,
which is induced by the thermo-optic effect and the thermal
expansion effect. We have demonstrated that the Fano resonanceof the cavity-based sensor has a similar sensitivity for the
resonant wavelength shift, but a higher sensitivity for intensity
variation, comparing with the Lorentzian resonance sensor. The
demonstrated PC cavity-based sensor offers potential for a
low-cost, high sensitivity homogeneous sensing in single on-chip
integration devices.

Aga He, Wen Xiao, Feng Pan, Beihang University (China)

10022-93, Session Post

Digital holography possesses the ability of numerically refocusing
a scene plane-by-plane from a hologram by selecting different
reconstruction distance, and an automatic focus algorithm isnecessary to quantify the focus degree of the reconstructed
images and determine the focused plane. In this paper, anautofocusing method is proposed that utilizes the cosine score
between the axial neighboring amplitude images. It is based on
the fact that the images near the focus contain more regularfeatures of object than in the defocused region, therefore, theneighboring reconstructed images are more similar to eachother at the focus position than at defocused and a cosine scoreis employed to evaluate such similarity. However, the cosinescores between the axial adjacent amplitude images are so
close that it is difficult to distinguish the extremum. Therefore,a modified cosine algorithm is presented to offset suchproblem on consideration of the correlation of the elements, by
subtracting the inner product term from the denominator of thecosine algorithm. The cosine and modified cosine score based
autofocusing method procedure is first introduced, and then it
is utilized in simulation and real holographic data. In simulation,
it precisely judges out the actual recording distance and thefocus curve shows good focus function criteria, which verifies themethod as an ideal circumstance. In real experiment, it can easily
search out the focus distance from the focus curve, and it shows
good focus judgement ability than most traditional focus metrics
selected. Therefore, the feasibility and validation of the proposed
autofocusing method are proved by simulation and experimentresults.

Application of the Microlens Array in the
projection of the Laser Scanning

98

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Lulu Wang, Xi’an Jiaotong Univ. (China); Min Li, Suzhou
Institute of Nano-Tech and Nano-Bionics (China); Hai Tan,
Changzhou Micro Innovation Technology Co., Ltd. (China);
Peng Zhou, Yu Bai, Wenjiang Shen, Dongmin Wu, Suzhou
Institute of Nano-Tech and Nano-Bionics (China)
Retinal scanning display (RSD) technology, as a new type ofhelmet-mounted display (HMD) technology, has been usedin virtual reality (VR) and augmented reality (AR) area, and it
has gradually become a hot research topic. However, a small
exit-pupil restricts the application of the RSD in the intelligent
head-mount display (HMD). In this paper, we use the microlens
array to solve this problem. We have designed a new process andprepared a circular-type microlens array with 70% fill factor in
the form of a hexagonal close-packed arrangement by melting
photoresist. The aperture size of the lens is 14?m and the period
is 16?m. The gap is coated with a metal film to reflect off thebeam which will not be modulated by the microlens. This canachieve a more uniform exit pupil expansion. An optical systemfor detecting pupil expansion performance was establishedin this paper. Simultaneously, we study the effect of different
defects of the microlens array for the pupil expansion. We also
demonstrate the function of the retinal scanning imaging withthe microlens array. The result shows that the NA and expansion
angle of the microlens array are greater than 0.28 and 33°. Afterthe expansion, the beam uniformity is more uniform, whichwww.spie.org/pa·

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Conference 10022:
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meets requirements for the helmet-mounted display needs, andachieves the goal of near eye display.

10022-94, Session Post

Gravure printing for electrophoretic
e-paper
Li Wang, Gui-Shi Liu, Yu-Wang Xu, Yu-Cheng Wang, Peng
Chen, Bo-Ru Yang, Sun Yat-Sen Univ. (China)
Color microcapsules have been prepared by some corporations
and they are better than the EPD with color filter in color
performance. Theoretically, the color microcapsule EPD without
color filter can be achieved if the color microcapsules could be
patterned in the desired area, respectively. However, it is virtuallydifficult to make these color capsules to be patterned andaligned with corresponding TFT pixels. We propose an interesting
technology with gravure process to achieve color EPD. The
proposed gravure process is as follows: Firstly, a conventional
photolithography was used to make the mother mold with photoresist (SU8) to define the shape and spatial deployment of thecapsules. Secondly, the Poly-Di-Methyl Siloxane (PDMS) was
further poured onto the SU8 mold and cured as a stamp. Thirdly,
the color capsules of EPD were coated with doctor blade. After
dried out the solvent, the spatially patterned EPD capsule withspecific colors are formed. Finally, the patterned EPD capsules
were transferred onto another target substrate with the aid ofcertain adhesive agent. Different color capsules were nested
together by repeating the above steps.
The reason for using SU8 is to make the high aspect ratio
geometry of trench, as well as precisely control the depth of thetrench to accommodate enough capsules to render well-defined
optical performances. While PDMS has better chemical inertness
and low surface energy which facilitate the transfer process.

10022-95, Session Post

Three-dimensional simulation and autostereoscopic 3D display of the battlefieldenvironment based on the particle system
algorithm
Jiwei Ning, Xinzhu Sang, Shujun Xing, Huilong Cui,
Chongxiu Yu, Binbin Yan, Beijing Univ. of Posts andTelecommunications (China); Wenhua Dou, Liquan Xiao,
National Univ. of Defense Technology (China)
In times of peace, the army’s combat training is still very
important, and the simulation of the real battlefield environmentis of great significance. Two-dimensional information has been
unable to meet the demand at present. With the developmentof virtual reality technology, three-dimensional (3D) simulationof the battlefield environment is possible. In the simulation of
3D battlefield environment,in addition to the terrain, combat
personnel, combat tool, the simulation of explosions, fire, smoke
and other effects is also very important, since these effects canenhance the sense of realism and immersion of the 3D scene.
However, these special effects are irregular objects which makes
it difficult to simulate with the general geometry. Therefore,
the simulation of irregular objects is always a hot and difficult
research topic in computer graphics. In the past decades, avariety of simulation algorithms have emerged, so far, the particle
system algorithm for simulating irregular objects is considered
to be the best algorithm and widely used for simulating irregular
objects.Here, the particle system algorithm is used for simulating
effects in the 3D battlefield environment.
In the paper, we researched and designed the simulation
algorithm of the explosions, fire, smoke based on particle system

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and applied it to the battlefield 3D scene. Besides, the battlefield
3D scene simulation with the glasses-free 3D display is carriedout with an algorithm based on GPU 4K super-multiview 3D
video real-time transformation method. In this algorithm, the 3D
scene is represented as the data format of “video + depth”, andthe 3D video is synthesized by super -multi virtual viewpoint
which is generated by view graph and the corresponding depth
map. At the same time, with the human-computer interaction
function, we ultimately realized glasses-free 3D displays ofthe simulated more realistic and immersive 3D battlefieldenvironment. The experimental results show that the algorithms
designed and realized by us are effective and feasible, and will
be widely used for simulation of complex objects and their 3D
display.

10022-96, Session Post

Vertex shading of the three-dimensionalmodel based on ray-tracing algorithm
Xiaoming Hu, Xinzhu Sang, Shujun Xing, Binbin Yan, Kuiru
Wang, Beijing Univ. of Posts and Telecommunications(China); Wenhua Dou, Liquan Xiao, National Univ. of
Defense Technology (China)
Ray tracing is a significant algorithm that can generate very
high quality and extremely realistic images, which can simulate
various physical phenomena like reflection, refraction, shadow
etc. Although the image generated by ray tracing is very
realistic, the rendering process is very time consuming without
any accelerating algorithm. Moreover, the rendering time of thealgorithm is influenced by the resolution of the generated image,
the number of the light source, the number of objects and the
distribution of the 3D scene. As a result, it is difficult to realize
real-time ray tracing of any 3D scene. Here, the optimizationof the entire ray tracing process is presented. With the opensource 3D engine library of OPENSCENEGRAPH, we wield the
ray tracing algorithm to color vertices of a model directly, as
well as a simple patch subdivision whenever needed. In this way,
good lighting effects are achieved and a considerable part ofthe calculation of the time-consuming intersection is effectively
avoided. In the case of high resolution, the efficiency of ray
tracing rendering is improved. At the same time, the results canbe directly saved as a 3D model with a global effect of lightand shadow, which extends the application range of ray tracing.
Due to the direct ray tracing operation in the 3D virtual scene,
the running time of the presented method only depends on
the number of triangular patches in the 3D scene (number ofvertices), the scene distribution and the number of light sources.
It is irrelevant to the screen resolution. In addition, once a 3D
scene rendering is completed, the model’s attitude can beobserved or changed from different angles, which will bring a lotof convenience for interaction and dynamic processing of the 3D
scene.

10022-97, Session Post

Real-time synchronized rendering ofmulti-view video for 8Kx2K threedimensional display with spliced four
liquid crystal panels
Huilong Cui, Xinzhu Sang, Shujun Xing, Jiwei Ning, Binbin
Yan, Beijing Univ. of Posts and Telecommunications(China)A high speed synchronized rendering of multi-view video for
8K?2K multi-LCD-spliced three-dimensional (3D) display system
based on CUDA is demonstrated. Because the conventional
image processing calculation method is no longer applicable#PhotonicsAsia

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
to this 3D display system, CUDA technology is used on 3D
image processing to address the problem of low efficiency. The
8K?2K screen is composed of four LCD screens, and accuratesegmentation of the scene is carried out to ensure the correct
display of 3D contents and a set of controlling and host softwares are optimally implemented to make all of the connected
processors render 3D videos simultaneously. The system which
is based on master-slave synchronization communication modeand DIBR-CUDA accelerated algorithm is used to realize the highresolution, high frame rate, large size, and wide view angle video
rendering for real-time 3D display. Experimental result showsa stable frame-rate at 30 frame-per-second and the friendly
interactive interface can be achieved.
This work is partly supported by the“863” Program(2012AA011902), the National Science Foundation of China(61575025) and the fund of the State Key Laboratory ofInformation Photonics and Optical Communications.

10022-98, Session Post

Three-dimensional scene capturing for thevirtual reality display
Jingsheng Dong, Xinzhu Sang, Nan Guo, Duo Chen,
Binbin Yan, Kuiru Wang, Beijing Univ. of Posts andTelecommunications (China); Wenhua Dou, National Univ.
of Defense Technology (China); Liquan Xiao, Beijing Univ.
of Posts and Telecommunications (China)
A virtual reality shooting and display system based on multiple
degrees of freedom camera is designed and demonstrated.
Three-dimensional scene display and the wide angle display
can be achieved easily and quickly through the construction
with the proposed system. The range of the viewing scene canbe broaden with the image stitching process, and the display inthe demonstrated system can achieve the effect of wide angle
for applications of image mosaic. In the meantime, the system
can realize 3D scene display, which can effectively reduce thecomplexity of the 3D scene generation, and provide a foundation
for adding interactive characteristics for the 3D scene in the
future. The system includes an adjustable bracket, computer
software, and a virtual reality device. Multiple degrees of freedomof the adjustable bracket are developed to obtain 3D scene
source images and mosaic source images easily. 5 degrees
of freedom are realized, including rotation, lifting, translation,
convergence and pitching. To realize the generation and displayof three-dimensional scenes, two cameras are adjusted into aparallel state. With the process of image distortion eliminating
and calibration, the image is transferred to the virtual reality
device for display. In order to realize wide angle display, thecameras are adjusted into “V” type. The preprocessing includes
image matching and fusion to realize image stitching. The mosaic
image is transferred for virtual reality display with its image
reading and display functions. The wide angle 3D scene display isrealized by adjusting different states.

10022-99, Session Post

Research situation and development trendof the binocular stereo vision system
Tonghao Wang, Bingqi Liu, Ordnance Engineering College(China); Ying Wang, Unit 63861 of PLA (China); Yichao
Chen, Ordnance Engineering College (China)
Since the 21st century, with the development of the computer andsignal processing technology, a new comprehensive subject thatcalled computer vision was generated. Computer vision covers awide range of knowledge, which includes physics, mathematics,
biology, computer technology and other arts subjects. It becomes

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more and more powerful, not only can realize the function of
the human eye “see”, also can realize the human eyes cannot. In
recent years, binocular stereo vision which is a main branch of
the computer vision has become the focus of the research in thefield of the computer vision. Binocular stereo vision is a kind of
the computer vision technology that can simulate human eyes todeal with the surroundings directly, which uses two cameras toshoot the same scenes at the same time, the three-dimensional(3D) images are collected. The 3D coordinate information of thescene is obtained automatically by this technology without touch.
In addition, binocular stereo vision also has such advantage as
simple structure, flexibility, reliability, wide range of applicationand so on, so it has been applied to many aspects of social
life, such as 3D reconstruction of image, robot navigation,industrial product testing and so on. In this paper, the binocularstereo vision system, the development of present situation
and application at home and abroad are summarized. With thecurrent problems of the binocular stereo vision system, his own
opinions are given. Furthermore, a prospective view of the futureapplication and development of this technology are prospected.

10022-100, Session Post

Interactive dynamic three-dimensional
scene for the ground-based threedimensional display
Peining Hou, Xinzhu Sang, Nan Guo, Duo Chen, Binbin
Yan, Kuiru Wang, Dou Wenhua, Liquan Xiao, Beijing Univ.
of Posts and Telecommunications (China)
Three-dimensional (3D) displays provides valuable tools formany fields, such as scientific experiment, education, informationtransmission, medical imaging and physical simulation. Groundbased 3D display with dynamic and controllable scene can findsome special applications, such as design and constructionof buildings, aeronautics, military sand table and so on. It canbe utilized to evaluate and visualize the dynamic scene of thebattlefield, surgical operation and the 3D canvas of art. In orderto achieve the ground based 3D display, the public focus plane
should be parallel to the cameras’ imaging planes, and opticalaxes should be offset to the center of public focus plane in bothvertical and horizontal directions. Virtual cameras are used todisplay 3D dynamic scene with Unity 3D engine. Parametersof virtual cameras for capturing scene are designed andanalyzed, and locations of virtual cameras are determined by
the observer’s eye positions in the observing space world. Aninteractive dynamic 3D scene for ground based 3D display isdemonstrated?which provides high-immersion 3D visualization.

10022-101, Session Post

A-star algorithm based path planning forthe glasses-free three-dimensional display
systemBin Yang, Xinzhu Sang, Shujun Xing, Huilong Cui,
Binbin Yan, Chongxiu Yu, Beijing Univ. of Posts andTelecommunications (China); Wenhua Dou, Liquan Xiao,
National Univ. of Defense Technology (China)
A-Star (A*) algorithm is a heuristic directed search algorithm
to evaluate the cost of moving along a particular path in the
search space, which can get the shortest path. Here, path
planning between any two points on the map is carried out. The
STAGE tool is used to manually add way points on the map anddetermine their spatial location. The adjacent waypoint witha waypoint ID is connected by the line segment to form thenavigation graph. A* algorithm can search the navigation graphto find the shortest path from a starting point to the destination.

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
The A* algorithm can restart searching for path from a certain
point, and the complex path can be divided in a plurality offrames. Since the navigation graph consists of the movable space,
it is considered the obstacle formed by static objects in thescene, and collision detection between the character and static
objects is not considered. A-star algorithm based path planning is
experimentally demonstrated on a glasses-free three-dimensional
display equipment, so that 3D effect of path finding can beperceived.

10022-102, Session Post

Electric breakdown of dielectric coatings
for high-voltage display applications
Gatis Mozolevskis, EuroLCDs, SIA (Latvia); Edgars Nitiss,
Univ. of Latvia (Latvia); Arturs Medvids, Riga Technical
Univ. (Latvia)
Smectic liquid crystal is the most promising material for smart
glass application due to infinite bistability and low haze at clear
state. To switch from scattering to transparent state up to 10x
higher voltage is needed than twisted nematics LCDs and is likely
for dielectric breakdown to occur. Thin film with high dielectricstrength and high transparency is required between ITO andliquid crystal.
In this work we have compared electrical and optical propertiesof SiO2 thin films with thickness up to 500 nm coated byflexographic printing and reactive magnetron sputtering
Current-voltage characteristics and dielectric breakdown values
show sputtered coatings to have higher dielectric strength. For
sputtered coatings with thickness >240 nm also self-healing
effect was observed. Self-healing mechanism will be discussed.

10022-103, Session Post

Visual discomfort caused by color
asymmetry in 3D displays
Zaiqing Chen, Xiaoqiao Huang, Chao Zhang, Junsheng Shi,
Lijun Yun, Yunnan Normal Univ. (China)
Color asymmetry is a common phenomenon in 3D displays,
which can cause serious visual discomfort. To ensure safe andcomfortable stereo viewing, the color difference between
the left and right eyes should not exceed a threshold value,
named as comfortable color difference limit. In this paper, wehave experimentally measured the limit of (dis)comfort color
difference by human observers viewing brief presentationsof color asymmetry image pairs. Five sample color points are
selected from the 1976 CIE u’v’ chromaticity diagram to measure
the comfortable color difference limits. As the presentations ofcolor asymmetry image pairs, left and right circular patches arehorizontally adjusted on image pixels with five disparity levels
and six color directions. The experimental procedure was wholly
controlled by the Software. First, one kind of color is randomly
selected from five sample points to fill the circular patch on theright half of the screen. Then, the left stimulus on the left half ofthe screen is randomly filled with a neighboring point color of
the sample point. And then a disparity level is randomly selectedfrom five disparities to move the left and right circular patches
horizontally on image pixels. The subject is asked to report
whether he/she feels visual uncomfortable when the stimulus
is presented. The experimental results showed that comfort
limits for each sample point varied with the disparity and color
direction. To analyze the results, we quantified the comfortable
color difference by drawing ellipses in the chromaticity diagram.
The semi-minor axis of the ellipses ranges from 0.0120 to 0.0301
in terms of the Euclidean distance in the u’v´ chromaticity
diagram and the semi-major axis ranges from 0.0210 to 0.0520.

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The database collected in this study greatly helps 3D systemdesign and 3D content creation.

10022-105, Session Post

The implementation of laser speckle
reduction based on MEMS twodimensional scanning mirror
Tingting Wang, Xi’an Jiaotong Univ. (China); Wenjiang
Shen, Suzhou Institute of Nano-Tech and Nano-Bionics(China); Shengli Wu, The School of Electronic andInformation Engineering, Xi’an Jiaotong University(China); Peng Zhou, Suzhou Institute of Nano-Tech andNano-Bionics (China); Jiahui He, Xi’an Jiaotong Univ.
(China); Huijun Yu, Suzhou Institute of Nano-Tech andNano-Bionics (China)
The laser display, a new display technology, involves optics,
electronics and system design. Laser display has many
advantages, such as wide color gamut, high brightness andlong lifetime. So it has strong potential in the market andimportant research significance in recent years. When laser
light was reflected from a screen surface, a high-contrast, finescale granular pattern would be seen by an observer looking
at the scattering spot. This type of granularity is so-called laser
speckle. This phenomenon is mainly due to the interferenceof the reflected light waves. Laser speckle, which decreases
image resolution and masks the image information, needs to be
suppressed.
With advantages such as miniaturization, mass production,
superior performance at high resonant frequency actuation,
MEMS micro-mirror becomes an ideal core component in many
fields. Compared with other speckle reduction methods, using
MEMS mirror is more efficient, lower cost, and simpler.
In this paper, we design and fabricate MEMS two-dimensionalscanning mirrors. The MEMS mirror has a reflective surface withdiameter of 15mm. This large reflective surface can handle highlaser optical power for projecting images with big lumens. We
design a system to reduce the laser speckle contrast based on
this MEMS two-dimensional micro-mirror. The MEMS mirror isdriven by electromagnetic force. The system will generate a large
number of independent speckle patterns when the laser beam isreflected by the scanning MEMS mirror. The speckle contrast canbe reduced to less than 4% through averaging these independent
speckle patterns.

10022-23, Session 5

Analytical description of quasi normal
modes in resonant metallic nano-grooves
Haitao Liu, Nankai Univ. (China); Fan Yang, Tsinghua Univ.
(China); Hongwei Jia, Nankai Univ. (China); Ying Zhong,
Tianjin Univ. (China)
We report an analytical model of quasi normal mode (QNM)
supported by metallic nano-grooves that form resonant
plasmonic nano-cavities [1]. The QNM is a solution of sourcefree Maxwell’s equations that satisfies the outgoing wave
condition at infinity, and has shown great advantages in providing
analytical descriptions of the frequency response of resonantnano-structures. However, the QNM itself is commonly obtainedwith numerical calculation which conceals its physical origin
and blocks an efficient design. The model shows that the QNM
originates from a resonance of the fundamental mode in eachgroove and their interaction via surface waves launched by eachgroove. Analytical expression for the complex eigenfrequency as#PhotonicsAsia

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
well as the field distribution of the QNM can be derived from themodel. Under external illumination of a plane wave, the legitimacy
for the expansion of scattered field with QNMs is justified withthe complex pole expansion theorem of meromorphic function
under a few assumptions on the scattered field. The expansion
coefficients of QNMs are analytically expressed in the modelwith a finite set of elementary scattering coefficients, which
avoids the calculation of the mode volume of QNMs that have aspatial divergence at infinity. The model also drastically reduces
the computational load of QNMs especially for a large ensembleof grooves for which the brute-force numerical tools are notavailable. The validity of the proposed model is tested against
full-wave numerical results.
[1] F. Yang, H. T. Liu, H. W. Jia and Y. Zhong, J. Opt. 18, 035003(2016).

Hyperbranched-polymer dispersed
nanocomposite volume gratings forholography and diffractive optics

10022-26, Session 5

Yasuo Tomita, Shinsuke Takeuchi, Satoko Oyaizu,
Hiroshi Urano, Taka-aki Fukamizu, The Univ. of ElectroCommunications (Japan); Naoya Nishimura, Keisuke Odoi,
Nissan Chemical Industries, Ltd. (Japan)
We describe the volume holographic recording properties ofphotopolymerizable nanoparticle-polymer composites (NPCs)
that incorporate hyperbranched polymer (HBP) acting astransporting organic nanoparticles. Synthesized HBPs are easy
to disperse in monomer without any substantive aggregation,
so that film samples with good optical quality are available.
It is also possible to control the size and refractive index bychemical treatment. They would behave themselves like hardnano-spheres in monomer. It is also possible to control and add
the optical properties and functionalities of HBPs by means ofchemical treatment of functional end groups. Here we describe
the performance of NPC volume gratings with various HBPs inphotopolymer. These HBPs include hyperbranched poly(ethyl
methacrylate), hyperbranched polystyrene and hyperbranchedtriazine/aromatic units whose refractive indices were 1.51, 1.61
and 1.82, respectively. Their heterogeneity indices showing
the relative size distribution of polymers were estimated by
the gel permeation chromatography to be 1.68, 4.86 and 4.40,
respectively. Each HBP was dispersed in monomer whoserefractive index was so chosen that a refractive index difference
between HBP and the formed polymer was larger. Suchsyrup was further mixed with a green-sensitive photoinitiator
titanocene for holographic recording measurements. We
used a two-beam interference setup to write an unslanted
transmission volume grating at grating spacing of 1 micron andat a wavelength of 532 nm. It is shown that volume NPC gratings
with the refractive index modulation amplitudes as large as
0.008, 0.004 and 0.02 can be recorded at their optimum HBP
concentration of 34, 34 and 25 vol.%, respectively. This resultshows the usefulness of HBP-dispersed NPC gratings for various
holographic applications.

10022-25, Session 5

A printable color filter based on the
micro-cavity incorporating a nano-grating
Yan Ye, Soochow Univ. (China)
A printable color filter based on the micro-cavity incorporating
a nanostructure is proposed, which consists of chromium (Cr)nano-grating, a dielectric layer and aluminium (Al) film. To figureout the influence on the reflection introduced by the nano-

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The simulation results show that for the micro-cavity, the same
resonant wavelength can be induced under different depths ofdielectric layer. Therefore, by introducing different depths forthe same resonant wavelength inside one period into a dielectric
layer, a nano-grating is obtained on top surface of the dielectric
layer. And its reflective spectrum shows that the bandwidth of its
reflective spectrum decreases much more compared to the oneof the spectrum for the micro-cavity. Furthermore, its reflective
efficiency at resonance is more than one time larger than the
one comparing to the reflection of the Cr nano-grating, which is
caused by reflective capability of the Al layer by comparing theircorresponding magnetic amplitude distribution at the resonant
wavelength.
For the micro-cavity can be a byproduct in the fabrication of the
proposed filter, they can be utilized together to realize a colorfuldisplay with different background for an anti-counterfeiting
certificate.

10022-24, Session 5

102

grating, the reflective characteristics of the micro-cavity with orwithout a nano-grating are analyzed by·

A small deployable infrared diffractive
membrane imaging system
Yue Zhang, Beijing Institute of Space Mechanics andElectricity (China)
Diffractive membrane imaging can be widely used in infrared
due to its longer minimum linewidth than used in visible lightand its loose requirement of RMS to fabricate easier and reduce
processing cycle and development cost. A small deployable
infrared diffractive membrane imaging system with 200mm
imaging aperture (actual aperture is 500mm) and 6U dimensions
was designed. The imaging system consists of deployablestructure than supports the infrared membrane under tension.
The imaging wavelength is >1?m, field of view is >1º, anddiffractive efficiency can be >60%. The technology is particularly
promising as a means to achieve extremely large opticalprimaries from compact and lightweight packages.

10022-27, Session 5

Design of soft x-ray varied-line-spacing
grating based on electron-beamlithography near-field lithography
Dakui Lin, Huoyao Chen, Univ. of Science and Technology
of China (China); Stefanie Kroker, Technische Univ.
Braunschweig (Germany) and Physikalisch-Technische
Bundesanstalt (Germany); Thomas Käsebier, FriedrichSchiller-Univ. Jena (Germany); Zhengkun Liu, Keqiang
Qiu, Ying Liu, Univ. of Science and Technology of China(China); Ernst-Bernhard Kley, Friedrich-Schiller-Univ. Jena
(Germany); Xiangdong Xu, Yilin Hong, Shaojun Fu, Univ. of
Science and Technology of China (China)
Soft x-ray varied line spacing gratings (VLSGs), being vital opticalelements for laser plasma diagnosis and spectrometry analysis
are conventionally fabricated by holographic lithography ormechanical ruling. Although soft x-ray VLSGs by holographic
lithography show lower stray light than those from mechanicalruling, the flexibility of density distribution from holographic
lithography is still limited by critical requirement to obtainaspecific wavefront. In order to overcome these issues a method
based on electron beam lithography-near field lithography (EBLNFH) is proposed. This combination simultaneously benefits from
EBL’s flexibility and NFH’s high throughput.

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
In this paper, we will show a newly designed soft x-ray VLSG
with a central groove density of 3600 lines/mm, which is to berealized based on EBL-NFH. First, the optimization of the spatial
distribution of line density and groove profile of the VLSG will beshown. As an important element in NFH, a fused silica mask plays
a key role during NFH in order to obtain a required line density
of VLSG. Therefore, secondly, the transfer relationship of spatial
distribution of line densities between fused silica mask and resist
grating will be investigated in different exposure modes during
NFH. We will propose a formulation about the transfer of line
density to design of the groove density distribution of a fusedsilica grating mask. Finally, the spatial distribution of line densities
between the fused silica mask, which is to be fabrication by using
EBL, will be demonstrated.

10022-28, Session 5

Antireflective subwavelength structures ata wavelength of 441.6 nm for phase masksof near-field lithography
Jinyu Li, Huoyao Chen, Univ. of Science and Technology
of China (China); Stefanie Kroker, Technische Univ.
Braunschweig (Germany) and Physikalisch-Technische
Bundesanstalt (Germany); Thomas Käsebier, FriedrichSchiller-Univ. Jena (Germany); Zhengkun Liu, Keqiang
Qiu, Ying Liu, Univ. of Science and Technology of China(China); Ernst-Bernhard Kley, Friedrich-Schiller-Univ. Jena
(Germany); Xiangdong Xu, Yilin Hong, Shaojun Fu, Univ. of
Science and Technology of China (China)
With the development of micro- & nanofabrication technology,
micro- & nanostructures have been widely used in many fields,
including spectroscopy, coding, sensor, subwavelength element,
etc. With phase masks realized by a combination of electron
beam lithography (EBL), near field lithography (NFH) has
great potential to fabricate versatile nanostructures, because it
combines the advantages of both lithographic methods.
Currently, subwavelength structures attract much attention due
to their various functions, such as antireflection, polarization
beam splitter and filter. In this presentation, aiming at reducing
the interface reflection of a fused silica mask of NFH at awavelength of 441.6 nm and incidence angles of either 0º or 32º.
First, we will compare the difference of antireflection property of
one-dimensional (1D) and two-dimensional (2D) subwavelength
structures with line density of 3600 lines/mm by simulation.
Then, the optimized 1D and 2D subwavelength structureswith 3600 lines/mm will be fabricated by using EBL-NFH
method. Finally, the antireflection property of these 1D and 2D
subwavelength structures will be characterized at the wavelengthof 441.6 nm.
Acknowledgement: The work was supported by the Sino-German
Center for Research Promotion (No. GZ 983) and German
Science Foundation DFG (No. IRTG 2101).

10022-29, Session 6

Fabrication of grating-Fresnel (G-Fresnel)lens by using PDMS based on soft
lithography
Kai Ni, Haifei Hu, Xinghui Li, Qian Zhou, Graduate Schoolat Shenzhen, Tsinghua Univ. (China); Xiaohao Wang,
Graduate School at Shenzhen, Tsinghua Univ. (China) andResearch Institute of Tsinghua Univ. in Shenzhen (China);
Jinchao Zhang, Graduate School at Shenzhen, Tsinghua
Univ. (China)

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Fabrication of a type of hybrid plane optics, GratingFresnel (G-Fresnel) lens, is presented in this research. A
polydimethylsiloxane (PDMS) based soft lithography technology
is employed. PDMS is poured onto the surface of a Fresnel lensand a negative Fresnel mold is formed after its being cured fortwo hours at a temperature of 65?. The formed Fresnel lens moldis peeled off and an anti-adhesion treatment for the Fresnel
surface is performed. Then the PDMS is sandwiched between thenegative Fresnel mold and a grating. After curing the sandwiched
PDMS at 65? for two hours, the Fresnel mold and the grating
are removed and a transmission-type Grating-Fresnel lens is
obtained. Optimization of the Grating-Fresnel lens is primarily
conducted. Two different surface treatment methods have been
proposed to solve the innate adhesion of PDMS layers during
PDMS double casting (PDMS-DC) technique. A fabrication system
is constructed and G-Fresnel with grating line spacing of 1.67
?m (600g/mm) and Fresnel lens with a diameter of 25.4 mm
and a focal length of 25 mm was successfully fabricated. Threedimensional surface profilometry has been performed to examine
the device quality. Measured results show that replicas remainhigh fidelity to its primary master mold. A miniature spectrometersystem was constructed to evaluate the performances of thisfabricated G-Fresnel lens. Experimental results verified thegrating fabrication method is effective and it can provide
comparable resolutions with the spectrometer using concave
grating.

10022-30, Session 6

Electro-optically and all-opticallyaddressed spatial light modulators basedon organic-inorganic hybrid structures
Vera Marinova, National Chiao Tung Univ. (Taiwan) andInstitute of Optical Materials and Technologies (Bulgaria);
Shiuan Huei Lin, Ken Yuh Hsu, National Chiao Tung Univ.
(Taiwan)
Two types of organic-inorganic hybrid structures: electrooptically controlled and all optically controlled, that canbe used as optically addressed spatial light modulator
devices, operating with fast temporal response, high spatial
resolution and in wide spectral range are presented and theirfunctionality demonstrated. Both devices are assembled by
doped inorganic Bi12SiO20 (BSO) crystals (characterized withexcellent photoconductivity and photorefractivity) and strong
birefringence of organic liquid crystal (LC), optimized withselected nanoparticles addition.
The operation principle of electro-optically controlled device
relays on electro-optical control of LC birefringence that allows
spatial modulation of the amplitude or the phase of the incident
beam. Supported by graphene –based electrodes, the proposed
device operates at low driving voltages, high contrast ratio andresponse time of about 100 ms. By projecting a video image
through the device a modulation of the pump light intensity isdemonstrated with the frame rate of 4.5 frames/sec.
Operation principle of all optically controlled device is basedon a surface activated photorefractive effect, photoinduced
in an inorganic substrate, acting as a driving force for LC realignment and refractive index modulation. Such configuration is
simple and easy to fabricate, without need of conductive layers,alignment layers and polarizers -all the processes are controlled
by light. Moreover, all optically controlled device operates at
Bragg matched regime of diffraction, where sub-micron spatial
resolution can be achieved.
Image patterns, optically addressed on the proposed organicinorganic hybrid structures reveal the spatial light modulation
ability and open future potentials for 3D display applications andimage processing.

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Conference 10022:
Holography, Diffractive Optics, and Applications VII

10022-31, Session 6

Polarization holography written byelliptically-polarized wave at a large crossYiying Zhang, Anan Wu, Jinliang Zang, Ying Liu, Xiaodi
Tan, Yong Huang, Guoguo Kang, Beijing Institute ofTechnology (China); Tsutomu Shimura, The Univ. of Tokyo(Japan); Kazuo Kuroda, Utsunomiya Univ. Ctr. for Optical
Research & Education (Japan)
Conventional hologram records information by varying theamplitude and phase. While Polarization holography employs
waves with two different polarization state. In this case,information of amplitude, phase and polarization state arerecorded on the polarization-sensitive materials. Here, weapply the new tensor theory which expresses the response of apolarization hologram as the tensor product or dyadic productto present the process of polarization holography. It breaches
the limit of small cross angle and can be applied to any arbitrary
forms of waves.
In the research of the new tensor theory, we have found somephenomena. For example, when linearly polarized waves areused for recording and reconstruction, faithful reconstruction
and orthogonal reconstruction can be realized by the illuminationof the original and orthogonal reference wave. In the case of
circularly polarized wave, we can also observe the phenomenaof faithful reconstruction and orthogonal reconstruction. In
this paper, we derive the elliptical polarization holography
theoretically to illustrate that both linear and circular polarization
holography are the particular cases of elliptical polarization
holography. Elliptical polarization holography is a more generalcase that can be applied to various conditions.

10022-32, Session 6

Realization of arbitrary full Poincaré
beams on the hybrid Poincaré sphere
Xiaohui Ling, Hengyang Normal Univ. (China); Xunong Yi,
Hubei Engineering Univ. (China); Zhiping Dai, Hengyang
Normal Univ. (China); Cheng-Wei Qiu, National Univ. ofSingapore (Singapore)

A holographic three-dimensional (3D) display in complex
modulation is the ideal 3D display. When observing the hologram,
3D display makes a great 3D images and complex modulationshows clearly and accurately. Method that we used to configure
the complex modulation is a multi-layered SLM(Spatial light
modulator). One method using cascaded amplitude and phase
only SLM and another way is multi-layered double phase SLM.
This system has the advantage of improving the disadvantagesof the conventional SLM. However, there are advantages anddisadvantages with each method. Thus, in this paper, we will
analyze the characteristics of the complex modulation andpresents the expected effects of the respective methods.

10022-34, Session 7

Interference pattern period measurement
at picometer level (Invited Paper)
Xiansong Xiang, Shanghai Institute of Optics and Fine
Mechanics (China) and Univ. of Chinese Academy of
Sciences (China); Chunlong Wei, Changhe Zhou, Shanghai
Institute of Optics and Fine Mechanics (China); Minkang
Li, Yancong Lu, Shanghai Institute of Optics and Fine
Mechanics (China) and Univ. of Chinese Academy of
Sciences (China)
To produce large scale gratings by Scanning Beam Interference
Lithography (SBIL), a light spot containing grating pattern isgenerated by two beams interfering, and a scanning stage is used
to drive the substrate moving under the light spot. In order tolocate the stage at the proper exposure positions, the period of
the Interference pattern must be measured accurately.
We developed a set of process to obtain the period value of
two interfering beams at picometer level. The process includes
data acquisition and data analysis. The data is received froma photodiode and a laser interferometer with sub-nanometer
resolution. Data analysis differs from conventional analyzing
methods like counting wave peaks or using Fourier transformto get the signal period, after a preprocess of filtering andenvelope removing, the mean square error is calculated between
the received signal and ideal sinusoid waves to find the best-fit
frequency, thus an accuracy period value is acquired, this method
has a low sensitivity to amplitude noise and a high resolution of
frequency.

The full Poincaré beam is a kind of beam whose polarization
distribution in its transverse plane covers all possible polarization
states in the traditional Poincaré sphere. We propose thatthe full Poincaré beam with any polarization geometries canbe pictorially described by a hybrid Poincaré sphere whose
eigenstates are defined as a fundamental-mode Gaussian beam
and a Laguerre-Gaussian beam. We further establish a robust andefficient experimental setup to generate any desired full Poincaré
beam on the hybrid Poincaré sphere, via modulating the incident
polarization state of light. Although the polarization geometryof the FPB will change upon propagation owing to its intrinsic
Gouy phase, we can employ two cascaded half-wave plates tocompensate the Gouy phase and obtain a desired full Poincaré
beam in a given propagation distance. Our research provides analternative way for describing and manipulating the full Poincaré
beam and an effective method to control the polarization state oflight and study the polarization singularities of light.

With 405nm laser beams interfering, a pattern period value
around 632nm is acquired by employing this process, fitting
diagram of the result shows the accuracy of the period value
reaches picometer level, which is much higher than the results of
conventional methods.

10022-33, Session 6

The spatial light modulator (SLM) plays more and more importantroles in variety of imaging applications. SLM can be used forbeam shape modification, aberration correction, image edge
enhancement, three-dimension display and so on. However,when the SLM is used as an optical phase modulator in someof practical imaging applications such as fluorescence adaptive
super-resolution microscopy, the imaging performance of theAnalysis of complex modulation withlayered spatial light modulators
SungJae Park, Hwi Kim, Korea Univ. Sejong Campus(Korea, Republic of)104

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10022-35, Session 7

Effect of optical surface flatness
performance on spatial-light-modulatorbased imaging system
Hongqiang Zhou, Yuhong Wan, Beijing Univ. ofTechnology (China); Ying Han, Beijing University ofTechnology (China); Tianlong Man, Fan Wu, Beijing Univ.
of Technology (China)

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
system could be affected by the flatness of the optical surfaceof SLM. Large amount of optical aberrations will be introduced
while the peak to valley (PV) value of the optical surface of
SLM is more than, for example, 10 percent of the wavelength of
the illumination light. Thus the point spread functions (PSF) of
the imaging system will be degrade and further decrease theresolution and signal to noise ratio of the system. In this paper,
we present a method for detecting and correcting the opticalaberrations is introduced by the optical surface flatness of SLM.
The aberrations are measured by capturing the hologram of the
SLM surface using the modified Mach-Zehnder interferometer.
The aberrations information is extracted directly from the phaseof the reconstructed image of the hologram. Then the conjugatedphase is displayed on the SLM to correct the aberration. The
imaging results show the resolution and signal to noise ratioof the system have been improvement by using the proposed
aberration detection and correction method. The effect of SLM
optical surface flatness on imaging characteristics are evaluatedquantitatively.

charge coupled device(CCD). Phase steps are introduced bymoving the grating with a linear stage monitored by a laserinterferometer. A series of interferograms are recorded as
the displacement is measured by the laser interferometer.
Secondly, to eliminate the tilt and piston error during thephase stepping, the iterative least square phase shift method
is implemented to obtain the wrapped phase. Thirdly, we use
the discrete cosine transform least square method to unwrap
the phase map. Experiment results indicate that the measured
wavefront has a nonlinear phase around 0.05@404.7nm. Finally,as the image grating is acquired, we simulate the print-error
written into the photoresist.

10022-36, Session 7

Jili Deng, Changhe Zhou, Shanghai Institute of Optics
and Fine Mechanics (China) and Shanghai Univ. (China);
Xiaona Yan, Shanghai Univ. (China); Chunlong Wei,
Yancong Lu, Shanghai Institute of Optics and Fine
Mechanics (China)

High-density grating pair for displacement
measurement
Changcheng Xiang, Changhe Zhou, Shubin Li, Zhumei
Sun, Shanghai Institute of Optics and Fine Mechanics(China)A novel structure consisting of a high density grating pair for
displacement measurement is proposed. When a laser beam
is incident normal to the closely placed high density grating
pair, efficiencies of transmission diffraction orders will change
periodically along with the relative displacement of the two
gratings in the grating period direction. The period of efficiencychange is due to the grating period, thus measurement of
displacement in the grating period direction can be accomplishedby detecting the power of diffraction orders. Unrelated tointerference of optical waves, this measurement is not sensitive tothe environment fluctuation. Simplified modal method, describing
the diffraction progress with the propagation of several grating
modes, gives simple and clear expressions to predict diffraction
efficiencies of the gratings. With simplified modal method, thegrating pair has been designed to be suitable for application.
Rigorous coupled wave analysis is also applied to calculate theperiodic efficiency change of the designed grating pair structure
to verify the design result obtained by simplified modal method.

10022-37, Session 7

Image grating metrology based on phasestepping interferometry in scanning beaminterference lithography
Minkang Li, Shanghai Institute of Optics and Fine
Mechanics (China) and Univ. of Chinese Academy of
Sciences (China); Changhe Zhou, Chunlong Wei, Wei
Jia, Yancong Lu, Changcheng Xiang, Xiansong Xiang,
Shanghai Institute of Optics and Fine Mechanics (China)
Large-sized gratings are essential optical elements in laser
fusion and space astronomy facilities. Scanning beaminterference lithography is an effective method to fabricate
large-sized gratings. To minimize the nonlinear phase written
into the photoresist, the image grating must be measured
to adjust the left and right beams to interfere in the waist. In
this paper, we propose a new method to conduct wavefront
metrology based on phase-stepping interferometry. Firstly,a transmission phase grating is used to combine the two
beams to form an interferogram which is recorded by a

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10022-38, Session 7

Research on a grating interferometer withhigh optical subdivision based on quasiLittrow configuration

Grating interferometers are widely used in the nanometer
displacement measurement. Compared with displacement laserinterferometers, the grating interferometers are less sensitivity to
the environment, including air turbulence, pressure, and humidity.
Because their measuring scale is grating period, which is morestable than wavelength in practical measurement. However, theresolution of grating interferometers is usually lower than thelaser interferometer. Therefore, in order to improve the resolution
and accuracy of grating interferometer, further study is needed.
As we known, the measuring resolution is determined by theelectronic subdivision and optical subdivision. In this paper, inorder to improve the optical subdivision, we present a gratinginterferometer based on the quasi-Littrow configuration. We
mainly use the plane mirrors to make the measuring lights reflectand diffract between the mirror and grating scale for manytimes. According to the grating Doppler shift, the more times
that measuring light diffracted by the grating scale, the higher
optical subdivision can be obtained. In theory, this kind of gratinginterferometer allows to increase the subdivision infinitely. But
it will be limited by the physical size and diffraction efficiencyof the grating scale in reality. Fortunately, the use of quasiLittrow configuration is very helpful to design and fabricate agrating scale with high diffraction efficiency. As an example,
a grating interferometer with an optical subdivision factor of
1/16 is designed. And the influence of grating motion error isalso analyzed. This work provides a technique to increase theresolution and accuracy of the grating interferometer, whichshould be interesting for high precision measurement.

10022-39, Session 7

Study of a grating interferometer withhigh optical subdivision techniques
Yancong Lu, Changhe Zhou, Shubin Li, Chunlong Wei,
Minkang Li, Xiansong Xiang, Jili Deng, Changcheng Xiang,
Wei Jia, Junjie Yu, Jin Wang, Chao Li, Shanghai Institute of
Optics and Fine Mechanics (China) and Univ. of Chinese
Academy of Sciences (China)
Displacement laser interferometers and grating interferometers
are two main apparatus for the micron-nanometer
displacement measurement over a long range. However, thelaser interferometers, which are based on the wavelength, are#PhotonicsAsia

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Conference 10022:
Holography, Diffractive Optics, and Applications VIIvery sensitive to the environment. On the contrast, the gratinginterferometers change the measuring scale from wavelength tograting period, which is much stable for the measurement results.
But the resolution of grating interferometer is usually lower thanthat of laser interferometer. Therefore, further investigation isneeded to improve the performance of grating interferometer. As
we known, the optical subdivision is a main factor that affects themeasurement resolution. In this paper, a grating interferometerwith high optical subdivision is presented based on the Littrow
configuration. We mainly use right angle prisms accompaniedwith plane mirrors to make the measuring lights diffracted by
the grating scale for many times. An optical subdivision factorof 1/32 can be obtained by this technique. A smaller opticalsubdivision factor can also be obtained, which is only limitedby the size and the diffraction efficiency of the grating scale.
Fortunately, the grating scale can be designed with very highefficiency due to the Littrow configuration, which is very helpful
to increase the optical subdivision. Additionally, the influenceon the measurement results that caused by motion errors ofgrating scale is also analyzed. Compared with traditional gratinginterferometers, this kind of grating interferometer can greatly
increase the measuring resolution and accuracy, which could be
widely used in nanometer-scale fabrications and measurements.

10022-40, Session 8

design and analysis of highly efficientreflective 1*3 splitting grating withtriangular structure
Jin Wang, Changhe Zhou, Jianyong Ma, Yonghong Zong,
Wei Jia, Yancong Lu, Shanghai Institute of Optics and Fine
Mechanics (China)
A highly efficient reflective 1*3 splitting grating with triangularstructure operating in 1.064?m wavelength under normal
incidence for TE polarization is designed. These subwavelength
gratings can be used as important optical elements in inertial
confinement fusion (ICF). For applications in high power laser
systems, an important requirement for the reflective gratings ishigh efficiency. The schematic of the grating with four layers:
SiO2, Au, Cr and SiO2 substrate. The first layer with SiO2 istriangular structure. This highly efficient triangular grating isdesigned by the vector theory. Rigorous coupled wave analysis(RCWA) and Simulated Annealing (SA) algorithm are adopted
to design and analyze the properties. The period and depth
are 1320nm and 350nm respectively. The theoretical efficiency
is nearly about 99%, which is much bigger than the efficiencyof traditional Dammann grating. The deviation of profile could
also influence the efficiency of the 1*3 splitting grating. The
error tolerance is analyzed by rigorous coupled wave analysis,
too. This structure has bigger tolerance, which is convenient for
fabrication. These reflective gratings as splitters should be useful
optical elements in the field of high-power laser as well as otherreflective applications.

10022-41, Session 8

Imaging performance tests of diffractive
optical system
Jianchao Jiao, Yun Su, Baohua Wang, Chao Wang, Yue
Zhang, Jiangao Jin, Beijing Institute of Space Mechanics
and Electricity (China)
Diffractive optical imaging is a new method to realize highresolution imaging from geostationary orbit(GEO). Technicaladvantages of diffractive optical imaging is analyzed in thefield of space optics. For application of super large diameter
space optical system, the system scheme and a new achromatic

106

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method is proposed. An imaging system is developed and tested,
the result of optical system wavefront is 0.169?(RMS), opticalsystem MTF is 0.85, and the imaging system MTF is 0.19. Test
results show the new achromatic method is feasible. The above
conclusions have reference significance for development of superlarge diameter diffractive optical imaging system.

10022-42, Session 8

High beam quality spectral beamcombined diode laser array
Quan Zhou, Changhe Zhou, Chunlong Wei, Shanghai
Institute of Optics and Fine Mechanics (China)
The 2.4 W spectral combined beam of a 19-element 940nm diodelaser array has been demonstrated in our experiment, and theefficiency of beam combining was 87% from free running laserbar. The outputs have been combined into a single beam with adiffraction-limited beam quality in the fast axis and M2< 20 in theslow axis. For high power diode lasers, beam quality was required
in a variety of the applications, such as material processing
and pumping of fiber and solid-state lasers. Spectral beamcombining (SBC) technology has been proved to be a solution
to scale the output power while maintaining the beam qualityof a single element. In the experiment, the laser bar consistedof 19 elements spaced at a 500 ?m pitch, each element was 100?m wide. The array was high-reflection coated on the back facet
and anti-reflection coated on the front facet, with a front facet
reflectivity of <0.5%. The beam combining was based on an
external cavity structure formed between the back facet of thelaser array and the output coupler. All the elements were focusedon a transmission grating by a cylindrical transform lens, and thegrating dispersed beams at a same direction, so all the elements
were spatially overlapped at the output coupler. The grating was
1410 lines/mm with 80% efficiency in -1st order. Because of theoscillation in the external cavity, the combining efficiency could
be higher than the grating efficiency, and even higher than 100%.
Each emitter received its own feedback from the output coupler.
This forced every element to lase at a different wavelength, while
the intensity was enhanced with the spectral beams.

10022-43, Session 8

Facial skin color measurement based on
camera colorimetric characterization
Yang Boquan, Shanghai Univ. (China); Changhe Zhou,
ShaoQing Wang, Shanghai Institute of Optics and Fine
Mechanics (China); Xin Fan, Chao Li, ShanghaiTech Univ.
(China)Color plays an important part in our visual system, the sameis true for Machine Vision system. When we observe humanbeing, his or her face attracts most attention, especially thecolor of the facial skin. Much information can be obtained fromthe color appearance of human face, such as race, age, healthand so forth. As human visual system is sensitive to small color
changes, hence, a subtle change in facial skin structure will resultin noticeable color difference to human. Therefore it is of great
importance to make a relatively objective measurement of facialskin color as well as the color difference of the same face at
different status.
In this paper, a simple but novel approach to measure the color of
facial skin was proposed. A new Skin Tone Color Checker madeof Pantone Skin Tone was designed to correct the color variancecaused by the different spectral sensitivity of cameras. Then astandard color target taken in the same illumination environment
as human face to characterize the camera so as to get a priorknowledge about how camera records color information. A facialwww.spie.org/pa·

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
color measurement procedure was developed in considerationof several previous algorithms, which is specially designed
considering the measurement purpose and experiment condition.
Finally, we compared the results obtained by our procedure
with these by spectrophotometer, and the validity as well as theaccuracy of our algorithm was verified.

Information Processing VIII, 92160Z, 2014; doi:10.1117/12.2061354.
[2] Denis A. Zherdev, Vladimir A. Fursov, “Support plane
method applied to ground objects recognition using modelled
SAR images” Proc. SPIE 9599, Applications of Digital Image
Processing XXXVIII, 95992J, 2015; doi: 10.1117/12.2188531.

10022-48, Session 910022-45, Session 8

Recent progress in holographic wavefront
sensing
Sergey B. Odinokov, Bauman Moscow State Technical
Univ. (Russian Federation); Vladimir Y. Venediktov,
Saint Petersburg Electrotechnical Univ. “LETI” (RussianFederation)
Many areas of optical science and technology require fast andaccurate measurement of the radiation wavefront shape. Today
there are known a lot of wavefront sensor (WFS) techniques,
and their number is growing up. The last years have brought a
growing interest in several schematics of WFS, employing theholography principles and holographic optical elements (HOE).
Some of these devices are just the improved versions of thestandard and most popular Shack-Hartman WFS, while other are
based on the intrinsic features of HOE. These are, for instancethe modal holographic WFS configurations and some others. The
paper presents the review of such techniques and the drawbacksof the demonstrated holographic WFS. Our studies have shownthat it reasonable and promising to shift the holographic WFS
design methods from the use of traditional analogous holograms
to the digital holography, employing the Fourier holography
technique. In the paper we describe the reasons for such
shift and demonstrate the results of numerical simulation andexperimental verification of such an approach.

10022-46, Session 8

Support subspaces construction applied
to object recognition using SAR images
Denis A. Zherdev, Samara Univ. (Russian Federation);
Vladimir A. Fursov, Samara Univ. (Russian Federation) andRussian Academy of Sciences Image Processing Systems
Institute (Russian Federation)
There are growing interest in using SAR images for object
detection and recognition. It can be explained by the low
sensitivity of observed data related to cloud cover, which restricts
the use of visible, near-infrared and radar satellite data. For
example, DARPA made a SAR images dataset (MSTAR) of groundtargets for experiments in object recognition. It is formed byairborne radar in spotlight mode with a resolution of 0.3 m ? 0.3
m with HH polarisation.
The main problem in SAR image recognition consists ofdepending on change of obtained object pose, an object shape,electromagnetic ground plane properties and etc. Therefore, acentral problem is in developing a method and an algorithm withless sensitivity to the changing pose of an obtained object. In thiswork, we suggest and examine an automatic algorithm for image
preparation and object recognition method based on using of
conjugation indices. The proposed recognition method also canbe applied to recognition of different kind of data.

Phase problems in optical imaging andlaser display (Invited Paper)
Guohai Situ, Wei Wang, Shanghai Institute of Optics andFine Mechanics (China)
It is well known that the phase contains more important
information about the field in comparison with the amplitude.
Therefore the imaging of phase is encountered in many branchesof modern science and engineering. Direct measurement of thephase is difficult in the short regime such as the visible light
due to the limited bandwidth of imaging sensors. One must
employ computational techniques to extract the phase from thecaptured intensity. In this talk, we will discuss the phase problems
encountered mainly in optical imaging and laser display. In
particular, we will talk about our previous works on iterative
phase retrieval techniques, and how they can be used to improve
imaging performance such as resolution and signal-to-noise ratio.

10022-49, Session 9

Zoomable three-dimensional computergenerated holographic display based on
shifted Fresnel diffraction
Hao Zhang, Liangcai Cao, Guofan Jin, Tsinghua Univ.
(China)Holographic three-dimensional (3-D) display has the potential
to provide all the depth cues that human eyes can perceive
since it can reconstruct the whole optical wavefront of the 3-D
scene. With the developments of spatial light modulators (SLMs)
and computer-generated holograms (CGHs), both real andvirtual 3-D scenes can be reconstructed dynamically without
the complicated interference recording systems. Layer-based
approaches can accelerate the CGH computing speed by slicing
the 3-D scene into a group of parallel layers according to its
depth map while maintaining the depth information. Fast Fouriertransform (FFT) can be implemented in the wave propagation
simulation between the parallel planes. However, the current
layer-based 3-D CGH algorithms suffer from the sampling
restrictions in the wave propagation simulations between thesliced layers and the hologram plane. In this study, we use
layer-based shifted Fresnel diffraction to simulate the wave
propagation from the sliced layers to the hologram plane withadjustable sampling rates. Shifted Fresnel diffraction can simulate
wave propagation between parallel planes with flexible sampling
rule. By introducing shifted Fresnel diffraction into layer-based
3-D CGH calculation, the holographic display system can zoom
the 3-D images without the optical zoom module. The resolutionsof reconstructed 3-D images can be adjusted accordingly. Opticalexperiments are performed with the help of a phase-only SLM
based holographic display system. The reconstruction results
demonstrate the effectiveness of our proposed method.

The development of ideas presented in [1,2] is continued in thisstudy. In the study, we extend our support plane method to caseof support subspaces, which have sizes higher than two vectors.
[1] Denis A. Zherdev, Vladimir A. Fursov, “Pattern recognition ofelectromagnetic field scattering from anthropogenic objects onunderlying surface” Proc. SPIE 9216, Optics and Photonics for

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Conference 10022:
Holography, Diffractive Optics, and Applications VII

10022-50, Session 9

Wave optic modeling of moire patterns on
curved surfaces and line-defect removal in
the fast-Fourier transform
Jeon Youngjin, Hwi Kim, Korea Univ. (Korea, Republic of)When display products manufactured, several functional
display panels are integrated. These combination of panels
cause unexpected optical problems. Moiré phenomenon is
one of representative issues in the display manufacturing.
In this presentation, we simulate the moiré pattern throughmathematical model based on computational wave optic theory.
Two curved surfaces those have different pattern are integrated
and consist of synthesis of polygons. We observe these panels
by changing the location of the observation. This simulation cancalculate the light field distribution of the deformed polygons.
Also, it is found that line-defects appear when we calculate thepolygon computer-generated hologram(CGH) by the fast Fouriertransform. When we calculate the angular spectrum CGH ofpolygon by the analytic method that based on formula, the exact
angular spectrum of polygon facets can be obtained. However,when we use numerical method that based on fast Fouriertransform, the discrete approximation of the continuous angular
spectrum integral induces some numerical errors. Therefore, tosolve this problem, we propose a partial filtering method of thephase-mismatched angular spectrum components of the polygon
object, where the phase-mismatched partial angular spectrum
components of the borders of the two adjacent triangular facetsis selectively filtered that should be removed when the two
adjacent triangular is connected.

Design of computer-generated hologram
apertures with the Abbe transform
The computer generated hologram (CGH) contains a very large
number of pixels, thanks to the modern fabrication technology
such as the e-beam lithography. According to the Abbetransform, the basic diffraction elements in a binary phase CGH
are the edges in the apertures, which act as an infinitely narrowslit, sending a light fan in the direction perpendicular to the edge
with the fan width inversely proportional to the edge length. The
diffraction pattern of the CGH is then a coherent summation of
all the light fans from all the edges of different orientations andlengths in the arbitrary-shaped apertures of the binary phase
CGH. For the arbitrary-shaped polygonal apertures with straightedges, the diffraction pattern is computed by analytical formulaof the Abbe transform whose computation time is independentof the size of the apertures. We propose to directly design thearbitrary-shaped polygonal apertures in the CGH with arbitrary
shaped triangular and quadrilateral apertures, and perform a
global optimization of the CGH using the Genetic Algorithm withlocal search, followed by an optimization of floating co-verticesof the elementary apertures. The experiments result in highperformance holograms with very low reconstruction error of 2 %for a grayscale image.

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10022-106, Session 9

Providing all depth cues for human eyes without eyewear devices,holographic display becomes one of the most promising display
technologies and is widely studied. However, there are still manybottlenecks limiting the applications of holographic display.
Here, we review our mainly investigation on the fast calculationof computer generated holograms (CGHs), the improvement of
display image quality and other aspects.
To realize dynamic and real-time interactive holographic display,
the CGHs should be acquired with high speed; while, the hugeamount of data in three dimensional (3D) scene slows down thecalculation. The improved look-up table methods are employing
to improve the calculating speed for the point source method,where the tables size are compressed. Polygon-based methods
with affine transformation are proposed. Furthermore, thedevelopment of parallel calculation platforms can realize theacceleration effectively. Moreover, the CGH data storage is also
optimized to achieve effective CGHs calculation and transmission.
There are many ways to improve the display image quality, andseveral algorithms are presented to render the color 3D scene,
where the spatial light modulators (SLMs) are the most common
optoelectronic devices, especially the phase-only liquid crystal(LC) devices. However, the pixelated SLMs have caused many
disadvantages. For overcoming the limitation of LC SLM, theassistant optical systems and devices are introduced to eliminate
the noise, widen the viewing angle, and enlarge the image size.
Different kinds of modulator are studied as well, including photoreduced graphene oxides elements, meta-surface, and quantum
dots material device to improve the display properties.
In summary, it is not only the algorithms, but also the systems
to be improved for the holographic display. The calculation
speed is accelerated, the CGH data storage amount is reduced,
the display effect is improved such as scene rendering, noise
elimination, color display, viewing angle, image size, as well as the

Jae-Hyeung Park, Inha Univ (Korea, Republic of)108

The second topic is the efficient implementation of the texture
map to the object surface. The texture map is the amplitude
distribution over the object surface which is frequently used incomputer graphics for realistic representation. We present anadaptive mesh division method to apply the texture map to thecomputer generated holography without significant increase of
the computational load.

Juan Liu, Beijing Institute of Technology (China)

Yunlong Sheng, Jing Wang, Univ. Laval (Canada)

Recent progress on fully analytic meshbased computer-generated holography(Invited Paper)

The first topic covered in the talk is efficient implementation of
the angular reflectance distribution of the object surface. The
angular reflectance distribution is important as it reveals surface
property of the object. In conventional methods, it has beenrealized by finding phase distribution on each mesh surface.
However, the phase distribution is obtained in discrete form in
the local plane of the mesh, and thus the fully analytic nature isdeteriorated, lowering the reconstruction quality. In this talk, we
present a method that uses convolution in the hologram plane,
which is efficient in calculation and maintains the advantages ofthe fully analytic process.

Review on holographic display and future
research trade (Invited Paper)

10022-51, Session 910022-52, Session 9

Computer generated holography plays a main role in thecontents generation for holographic displays and digital archivingof three-dimensional objects. The fully analytic mesh based
computer generated holography finds exact complex opticalfield for each triangular mesh of the three-dimensional objects
for given sampling interval in the hologram plane without any
approximation, enhancing the quality of the reconstruction. The
mesh based processing rather than conventional point based one
makes it compatible with most computer graphics techniquesand efficient especially for large objects. In this talk, we present
a few recent progress on fully analytic mesh based computer
generated holography techniques.

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Conference 10022:
Holography, Diffractive Optics, and Applications VII
novel micro-/nano- modulators etc. Though there are still issues
stunting the development, with the further study on optics andother fields, it is believed that the real-time full-color holographic
display with high image quality and excellent visual experience
will be realized and applied in daily life in the near future.

10022-55, Session 10

10022-53, Session 10

Chao Zuo, Nanjing Univ. of Science and Technology(China)New explanation for the Talbot effect:
simplified modal method
Shubin Li, Changhe Zhou, Yancong Lu, Shanghai Instituteof Optics and Fine Mechanics (China)
Talbot effect, a classical optical phenomenon, was firstly foundin 1831. Talbot effect has wide applications in modern opticalsystems, especially the Talbot effect of a grating. When thegrating period is larger than the wavelength, the Talbot effect ispolarization-independent and we can use the scalar optics theory
to simulate the Talbot effect. When the grating period is close
to the wavelength, the Talbot effect is polarization dependent
generally. However, the polarization-independent Talbot effectis also existing when the diffraction efficiencies and phasemeet some conditions for a high-density grating. We can use
the simplified modal method to illustrate the Talbot effect of ahigh-density grating, which is a physical method and can offer
us much physical insight about the diffraction process. Based on
this simple method, we will give a new explanation of the Talbot
effect. We hope this theoretical work can boost the practicalapplications of Talbot effect.

10022-54, Session 10

Design and analysis of broadband
diffractive optical element for chromaticaberration correction
ShaoQing Wang, Changhe Zhou, Shanghai Institute of
Optics and Fine Mechanics (China)
A modified direct binary search (MDBS) algorithm is proposed
to design the broadband diffractive optical element (DOE) for
chromatic aberration correction. To speed up the diffracted
field computation, the search tragedy of DOE’s groove heights
is special optimized. To analyze the DOE’s broadband focusing
ability, these focuses of FdC wavelengths are simulated byusing field tracing method, and the achromaticity of the DOE
is also quantified by comparing each wavelength’s PSF to thereference wavelength’s PSF. Moreover, the DOE’s profile is also
exported to user-defined surface to analyze the geometric and
RMS focus in commercial optical design software. As we all
known, DOE’s fabrication errors play an important role on SNR
and diffractive efficiency, the tolerances of fabrication errorsof DOE are numerically studied by adding random errors andusual fabrication errors. In real application, low SNR means that
too much noise light are diffracted, which may form disastrous
ghost spot or ghost line. In order to improve the DOE’s SNR,
the whole DOE is divided to several sub-apertures, and each
sub-aperture’s micro-structure is designed by MDBS separately.
Numerical results show that by this mean the SNR can beincreased, because statistically it’s low probability that all subaperture’s noise light emitted to the same target zone that results
unexpected ghost spot or ghost line. The impact of oblique lightis also simulated and chromatic aberration degrades significantly.
Summarily, besides small focus size, results also show that thedesign offers polarization insensitive, error tolerant, high SNR,
and great design flexibility.

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Multi-modal computational microscopy
with programmable illumination andcoded aperture (Invited Paper)

Computational microscopy is an emerging technology which
extends the capabilities of optical microscopy with the
combination of optical coding and computational decoding.
It provides us with novel imaging functionalities or improved
imaging performance which are diffcult or impossible to achieveusing a conventional microscopic system. Recent advance in LED
lighting and digital display technology provide new opportunities
for active digital illumination and imaging control foradvancing microscopy. In this paper, we report our most recent
developments of computational microscopy with programmable
illumination and coded aperture. We describe several new
approaches for achieving multi-modal computational imaging,including contrast-enhancement imaging, quantitative phaseimaging, light field imaging, and lens-less tomographic imaging,with use of a programmable LED array or a programmable LCD
panel.

10022-56, Session 10

Photorefractive and computational
holography in the experimental generationof single arrays and superposition of
nondiffracting beams
Marcos R. R. Gesualdi, Rafael A. B. Suarez, Indira S. V.
Yepes, Tárcio de Almeida Vieira, UFABC (Brazil); Michel
Zamboni-Rached, Univ. Estadual de Campinas (Brazil)
This work presents the optical generation of nondiffracting
beams via computational holography and, for the first time, via
photorefractive holography. Optical generation of nondiffracting
beams using conventional optics components is difficult
and, in some instances, unfeasible, as it is wave fields given
by superposition of nondiffracting beams. It is known thatcomputational holography and computer generated holograms
implemented in spatial light modulators (SLMs) successfully
generate such beams. With photorefractive holography
technique, the hologram of a nondiffracting beam is constructed(recorded) and reconstructed (reading) optically in a nonlinear
photorefractive medium. The experimental realization of
nondiffracting beam was made in a photorefractive holography
setup using a photorefractive silenite crystal (BSO/BTO) as
holographic recording medium, where the nondiffracting beams(Bessel, Airy, Mathieu and Parabolic), the nondiffracting beamarrays and superposition of co-propagating nondiffracting beams
were obtained experimentally. The experimental results are inagreement with the theoretically predicted presenting excellent
prospects for implementation of this technique for dynamicalsystems at applications in optics and photonics.

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10023 Optical Metrology and Inspection for Industrial Applications IV

10023-1, Session 1

10023-4, Session 1

Precision measurement technology basedon femtosecond frequency comb (Invited
Paper)FPGA-based real-time phase measuring
profilometry algorithm design andimplementation

Weihu Zhou, Academy of Opto-Electronics, CAS (China)

Guomin Zhan, Hongwei Tang, Zhongwei Li, Kai Zhong,Huazhong Univ. of Science and Technology (China)

In the past decade, remarkable advance associated withmeasurement technology of frequency comb have been acquired
owing to rapid development of femtosecond frequency comb.
The frequency comb can produce millions of sharp laser lines in a
precise evenly spaced grid spanning much of the visible and nearinfrared spectrum. It has been widely used in optical metrology,
such as absolute distance measurement, frequency or wavelength
metrology and surface measurement. It also can be used forspectrograph measurement, frequency synthesis and attosecond
pulse generation because of its excellent characteristic in timeand frequency domain. This paper will focus on absolute distancemeasurement technology based on optical frequency comb.
Several kinds of absolute distance measurement methods withfemtosecond frequency comb will be discussed. Meanwhile,
applications of optical frequency comb in time and frequency
transfer, surface tomography measurement will be introduced.

10023-3, Session 1

Phachara Phongwisit, Prathan Buranasiri, King Mongkut’s
Institute of Technology Ladkrabang (Thailand)

Meng Chen, Qun Hao, Yao Hu, Shaopu Wang, Tengfei Li,
Lin Li, Beijing Institute of Technology (China)
Aspheric optical components are an indispensable part ofmodern optics systems. With the constant development ofaspheric optical fabrication technique, high-precision figure
error testing method of the aspheric surfaces is a quite urgent
issue now. We proposed a digital Moiré interferometer technique(DMIT) based on partial compensation principle for aspheric andfreeform measurement. Different from traditional interferometer,
DMIT consists of a real and a virtual interferometer. The virtualinterferometer is simulated with Zemax software to perform
phase-shifting and alignment. We can get the results by aseries of calculation with the real interferogram and virtualinterferograms generated by computer. DMIT requires a specific,
reliable software system to ensure its normal work. Imageacquisition and data processing are two important parts inthis system. And it is also a challenge to realize the connection
between the real and virtual interferometer. In this paper, we
present a software system design for DMIT with friendly userinterface and robust data processing features, enabling us toacquire the figure error of the measured asphere. We choose
Visual C++ as the software development platform and control theideal interferometer by using hybrid programming with ZEMAX.
After image acquisition and data transmission, the system calls
image processing algorithms written with MATLAB to calculate
the figure error of the measured asphere. Finally, we test thesoftware system experimentally. In the experiment, we realize themeasurement of an aspheric surface and prove the feasibility ofthe software system.

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10023-5, Session 1

Elongation measurement using onedimensional image correlation method

Software system design for the non-nulldigital Moiré interferometer

110

Phase measuring profilometry (PMP) has been widely used inmany fields. However, the instruction time delay in the computercaused by numerous repetitive operations greatly limit theefficiency of data processing. To solve this problem, we haveproposed a method of PMP system based on FPGA with theadvantages of pipeline architecture and parallel execution. In
this paper, we design a fully pipelined hardware architecture for
PMP. The entire hardware system on the basis of multi-frequency
heterodyne principle includes rectification, phase calculation,phase shifting, stereo matching and triangulation. Finally, we
analysis experiment results and the factors which may influence
results. The results show that the measurement speed andaccuracy can meet the desired requirements.

Aim of this paper was to study, setup, and calibrate an elongation
measurement by using 1- Dimensional Image Correlation method(1-DIC). To confirm our method and setup correctness, calibration
with other method is required. In this paper, we used a small
spring as a sample to find a result in terms of spring constant.
With a fundamental of Image Correlation method, an image offormed and deformed sample were compared to understand thedifference between deformed process. By comparing the locationof reference point on both image’s pixel and calculate result interm of elongation. After that, elongate and force on samples
were compared to find a spring constant in the same way as
Hook’s law. The results from 1-Dimensional Image Correlationand Hook’s law were different by 5 percent. This method can beapplied to measure the elongation of a small fiber samples morevariously.

10023-6, Session 1

A vision weight method of billet based onlinear structure laser
Fengshan Huang, Yusong Ren, Li Chen, Hebei Univ. of
Science and Technology (China)
In order to upgrade the cut-by-length technology of billet tocut-by-weight, a real-time accumulation vision weight methodof billet based on linear structured laser was proposed, andits principle, measurement model and weighing process werestudied. According to the vision measurement principle oflinear structure laser, the current cross section area of billet wasmeasured and calculated by two vision sensors. Meanwhile, thedistance between the current cross section and the previous
one was acquired by another vision sensor, and the billet
weight between two adjacent cross sections was calculated
and accumulated. Thus, the billet weight passing the measuringwww.spie.org/pa·

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
position was monitored real-timely, and the real-time weight-cut
control of billet was realized. The experimental system was set
up and the weight experiment was carried out with rectangularsolid steel. Experimental results show that the relative error ofweight is1‰, which is far less than 8‰ used in present production
enterprises. This research provides a theoretical reference for therealization of billet cut-by-weight technology.

10023-7, Session 1

Spindle error motion measurement using
concentric circle grating and sinusoidal
frequency-modulated semiconductor
lasersMasato Higuchi, Masato Aketagawa, Thanh Vu, Nagaoka
Univ. of Technology (Japan)
The conventional method of measuring the radial, axial andangular spindle motion is complicated and needs large spaces.
Smaller instrument is better in terms of accurate and practicalmeasurement. A method of measuring spindle error motion
using a sinusoidal phase modulation and a concentric circle
grating was described in the past. In the method, the concentric
circle grating with fine pitch is attached to the spindle. Three
optical sensors are fixed under grating and observe appropriate
position of grating. The each optical sensor consists of asinusoidal frequency modulated semiconductor laser as thelight source, and two interferometers. One interferometermeasures an axial spindle motion by detecting the interference
fringe between reflected beam from fixed mirror and 0th-orderdiffracted beam. Another interferometer measures a radial
spindle motion by detecting the interference fringe between±2nd-order diffracted beams. With these optical sensors, 3 axial
and 3 radial displacement of grating can be measured. Fromthese measured displacements, axial, radial and angular spindle
motions are calculated concurrently. In the previous experiment,
concurrent measurement of 5 axis (1 axial, 2 radial and 2 angular)
spindle motion at 4rpm was described. In this paper, concurrent
measurement of the 5 axis spindle motion at 4000rpm would be
described.

10023-8, Session 2

Phase-shifting interferometry and its
applications (Invited Paper)
Shouhong Tang, Suzhou H&L Instruments LLC (China)
Phase shifting interferometry (PSI) is a highly effective method
for measuring the optical path difference (OPD) between two
reflective surfaces. It has been widely used in applications suchas optical testing and surface profiling due to its outstanding
nanometer accuracy and precision. As technologies, especiallythe digital hardware and software, have rapidly developed inrecent years, the method has found its fresh applications thatare hard to imagine before. For example, it is well accepted tomeasure the flatness, nanotopography, and thickness variationof wafers. This is because PSI is able to meet the measurement
needs as the semiconductor industry progressing down theroadmap to smaller device geometries. The method has many
significant advantages including rapid data acquisition, improving
the measurement sensitivity, and increasing the measurement
accuracy and precision. In this presentation we will givedetails about the principle of PSI, illustrate how to use it, anddemonstrate its advantages with measurement results fromour tools. We will also show the outcome of its applications insemiconductor industry.

10023-11, Session 2

Concentricity calibration ofphotogrammetry retro-reflector target
Hengzheng Wei, Wei Nong Wang, Limei Pei, Guoying Ren,
National Institute of Metrology (China)
Digital Photogrammetry System is widely used in recent years
due to its fully functional, accurate measurement, and noncontact portable feature. Especially it is suitable for large objects
measurement. The measurement is usually carried out with amobile retro-reflector target, which is consists of hemispheres
and reflective signs fixed in the center of the hemisphere. Whenthe center of the sphere and the center point of the reflectors do
not overlap, it will introduce measurement error. Therefore, theconcentricity of target is an important measurement parameterfor the measurement result.
To achieve the concentricity of the target a multisensor
coordinate measurement machine with imaging probe andcontact probe is used. In this combined measurement system
the contact probe measure the sphere center of the target, andimage probing measure the center of reflective sign. An artifact
is designed to evaluate the performance of combined system.
This artifact is defined a sharp edged hole in a metal plate. It is
suitable to measure with touch probe as well as imaging probe.
First the touch probe measures 25 points on the hole and thenwith the imaging probe. With all the points measured by two
kinds of probe the evaluation parameters including combination
size error, form error and location error are calculated. These
parameters are consistent with the ISO standard 10360-8. The
results indicate that there is a big systematic offset between thetwo sensors. To make an improvement a data fusion method
based on a transform with coordinates of hole centers is applied.
It indicates that measurement uncertainty combined system is 5
microns which can meet the target calibration requirements.

10023-12, Session 2

Three-dimensional endoscopic
measurement by uni-axis grating
projection
Geliztle A. Parra Escamilla, Fumio Kobayashi, Yukitoshi
Otani, Utsunomiya Univ. (Japan)
Three-dimensional endoscopic measurement can be archieved byan Uni-axis image guide fiber system to reconstruct the surface.
The surface variation of the samples is retrieved by using fringe
contrast modulation and the technique takes into account thedefocus change and the encoding information on the fringe
contrast of the projected structured light pattern. In the second
part we implement a 2D Fourier Transform filter for remove thebaseline information for increasing the fringes contrast and also
we improved the fitting function for better results in the 3D
reconstruction. Experimental results will be presented.

10023-13, Session 2

A field calibration method to eliminate theerror caused by relative tilt on roll angle
measurement
Jingya Qi, Xian Jiaotong Univ. (China); Zhao Wang,
Junhui Huang, Xi’an Jiaotong Univ. (China); Bao Yu, Xi’an
Jiaotong Univ. (China); Jianmin Gao, State Key Lab. for
Manufacturing Systems Engineering (China)
The roll angle measurement method based on a heterodyne

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111

Conference 10023: Optical Metrology and Inspection
for Industrial Applications IVinterferometer is an efficient technique for its high precision andenvironmental noise immunity. The optical layout bases on apolarization-assisted conversion of the roll angle into an opticalphase shift, read by a beam passing through the objective plate
actuated by the roll rotation. The measurement sensitivity or
the gain coefficient G is calibrated before. However, a relative
tilt between the laser and objective plate always exist due tothe tilt of the laser and the roll of the guide in the field long rail
measurement. The relative tilt affect the value of G, thus resultin the roll angle measurement error. In this paper, a method forfield calibration of G is presented to eliminate the measurement
error above. The field calibration layout turns the roll angle into
an optical path difference (OPD) by a rotary table. Thus, the rollangle can be obtained from the OPD read by a conventional
two-frequency interferometer. Together with the phase shift,
an accurate G in field measurement can be obtained and themeasurement error can be corrected. Besides that, we can alsoenhance the measurement sensitivity by optimizing the tilt of
the objective plate based on the value of the measurement G.
The optical system of the field calibration method is set up andthe experiment results are given. Contrasted with the Renishaw
XL-80 for calibration, the proposed field calibration method canobtain the accurate G in the field rail roll angle measurement.

10023-14, Session 2

The study of fast measurement
hexahedron verticality error by wavefront
interferometer
Peng Shijun, Songtao Gao, Wu Dongcheng, Erlong Miao,
Changchun Institute of Optics, Fine Mechanics andPhysics (China)
We present a method for measuring hexahedral adjacent sidesof the vertical error by wavefront interferometer. The verticalerror of hexahedral adjacent faces is obtained from comparing
the hexahedral prism, which is placed on a stable three-point
support tooling, with wavefront interferometer reference surface
and using the least squares method. Firstly, the measurement
system and measurement experimental procedure is introduced.
Second, the method of least squares vertical evaluation method
is described in detail and a lot of repeatability measurement
experiments have done. Finally, the hexahedral adjacent sides ofthe vertical error are measured both by coordinate measurement
machine and wavefront interferometer. The measurement
results are basically the same, which proved the method of
measuring the results credible. It is found that the measurement
accuracy of the method is better than 0.5sec through analysis ofmeasurement data. This method not only has high accuracy but
also both sides of the adjacent vertical error distribution data canbe obtained directly. And the vertical error distribution data canbe used to guide hexahedral bit error in high precision machining
modification.

10023-80, Session 2

Performance analysis of three-dimensionalsurface profilometry using a MEMS mirror
Yuxin Cheng, Sining Li, Guohang Shan, Harbin Institute ofTechnology (China)
Accurate 3D shape measurement has played an increasingly
important role in various diverse industrial applications, such as
manufacturing, robot vision etc. To achieve a low cost, compact
3D profiling system, a phase shifting scheme with a single MEMS
scanner has been proposed and studied by some international
colleagues. In this paper, we established a mathematical modelfor the 3D profiling system to reconstruct surface contour of112

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the object. A data processing flow chart is designed, and thealgorithm is developed correspondingly, in which some means
to improve accuracy are also taken into consideration. Then,numerical simulation for the whole working processing of the
profiling system is performed according to the theoreticalmodel. The simulation results are analyzed in detail to get the
optimal parameters. In order to verify the feasibility of thescheme, we build an experimental setup and carry out a series ofexperiments. The results show that the RMSE is about 6% and therange resolution is about a few millimeters.

10023-81, Session 2

Quadrant-division technique fordifferential sensitivity optical beammeasurement
King Ung Hii, Swinburne Univ. of Technology, Sarawak(Malaysia)
Optical beams with high collimation degree are requiredin numerous optical applications such as metrology. The
conventional approaches of adapting the double-passand quadruple-pass configurations into a lateral shearing
interferometer for the improvement of collimation testing
sensitivity have shown limitation to increase further thenumber of passes of the test beam in the system due to theirconfigurational constraint. Intrinsically, it is necessary to increase
the number of passes in order to improve the sensitivity of thesystem further.
In this work, we present a technique where the collimating lens
is utilized in a way of four different quadrants in order to allow
further increment on the number of passes of the test beam toeight times. Generally, the quadrant-division approach make useof a collimating lens in four parts of quadrants, namely quadrants
I, II, III, and IV. Instead of aligning the test beam onto the center ofthe collimating lens, the beam is directed onto the first quadrant
and configured to pass the subsequent quadrants. This creates
the first four-pass. Subsequently, a total number of eight passes
can be achieved by reversing the test beam after the first fourpass. Hence, for a defocus introduced, the collimation state of
the test beam can be evaluated at the amplification of eight. In
the simulation experiment, for a beam size of 4 mm in diameter,
the minimum detectable divergence angle of [theta]div.=1.1?103 degrees is achieved. The corresponding minimum detectablewavefront height is found to be (Wo)min = 0.015[lambda].

10023-15, Session 3

Requirements of precision and innovative
manufacturing for ultrahigh precisionlaser interferometry of gravitational-wave
astronomy (Invited Paper)
Wei-Tou Ni, Sen Han, Tao Jin, Univ. of Shanghai for Scienceand Technology (China)
With the LIGO announcement of the first direct detectionof gravitational waves, the Gravitational-Wave Astronomy
was formally ushered into our age. After one-hundred yearsof theoretical investigation and fifty years of experimental
endeavor, this is a historical landmark not just for physics
and astronomy, but also for industry and manufacturing.
The challenge and opportunity for industry is precision andinnovative manufacturing in large size – production of large andhomogeneous optical components, optical diagnosis of large
components, high reflecting dielectric coating on large mirrors,
manufacturing of components for ultra-high vacuum of large
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Conference 10023: Optical Metrology and Inspection
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system, production of high-power high-stability single-frequency
lasers, production of high resolution positioning systems etc. In
this talk, we address and review the requirements and methods
to satisfy these requirements.
Large Optical diagnosis of large optical components requires
large phase-shifting interferometer; the 1.06 ?m Phase Shifting
Interferometer for testing LIGO optics and the recently built 24”
phase-shifting interferometer in Chengdu, China is an extensionof it. High quality mirrors are crucial for laser interferometric
GW detection, so as for ring laser gyroscope, high precisionlaser stabilization via optical cavities, quantum-optomechanics,
cavity quantum electrodynamics and vacuum birefringencemeasurement. There are stringent requirements on the substratematerials and coating methods. For cryogenic GW interferometer,
appropriate coating on sapphire or silicon are require for thermaland homogeneity property. Large ultrahigh vacuum components
and high attenuating vibration system together with an efficientmetrology system are required and will be addressed.

10023-16, Session 3

Illumination fluctuation elimination inphase-shifting technique by use of agray-level transformation based on fringe
histograms
Ruihua Zhang, Hongwei Guo, Shanghai Univ. (China)
Phase-shifting technique has been extensively employed in
optical metrology by taking advantage of high resolution. Most
phase-shifting algorithms assume the background intensity
and modulation at each point of the captured fringe patterns
to be constant during phase shifting, so that these two values
together with the phase, as three unknowns, can be calculated
from at least three phase-shifting intensities. In measurement
practice, however, the background intensities and modulations of
captured fringe patterns do not always keep constant under the
influence of the voltage fluctuations and the unsteadiness of theambient light, so the illumination fluctuation may lead to errors
in the calculated phase, and thereby decrease the measurement
accuracies with phase-shifting technique. To solve this problem,
this paper presents an intensity correction method by use ofa gray-level transformation based on the histograms of fringe
patterns. A fringe pattern containing bright and dark fringes canbe recognized as an image having two classes of pixels following
a bimodal histogram. We segment each fringe pattern by using
the optimal threshold based on maximumizing the inter-classvariances. Noting that the means of the semented classes areinesnsitive to the phase shifts, but change with the illimination
fluctuations, we establish a linear gray-level transformation
function, by which the fluctuations of this fringe pattern inbackground intensities and modulations can be corrected.
Numerical simulation and experimental results demonstrate theproposed method to be efficient and effective in improving thephase measuring accuracies with phase-shifting technique.

10023-17, Session 3

Development of an optical technique formeasurement of centering error of glass
molds for production of ophthalmic lenses
Boonsong Sutapun, Saharat Kaew-aram, Suranaree
Univ. of Technology (Thailand); Armote Somboonkaew,
Ratthasart Amarit, National Electronics and Computer
Technology Ctr. (Thailand)
Manufacturing of plastic ophthalmic lenses requires glass molds
for the casting process. The two molds are held together by a

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sealing gasket ensuring that a defined distance between thetwo molds is maintained. The liquid monomer is filled into themolds and hardens to form a plastic lens when exposed to athermal process for many hours. During the production process,the geometric center of both molds may be displaced fromeach other. The cast plastic lenses from such molds will havethe geometric center decentered from the optical center; as aresult, the lens’ prism diopter could be out of the preset range.
Therefore, to improve the production yield, it is important toinspect the centering error of the assembled molds prior themonomer filling step. In this work, we have been developing an
optical apparatus for measurement of centering error of theassembled glass molds for the production of the ophthalmic
lenses. The working principle of the instrument is based on
a reflection-mode autocollimator with an addition objective
lens to focus at the center of curvature of both inner surfacesof the glass molds. The image reflected from the glass moldsurface is observed by a camera. When a centering error occurs,
the observed image depicts as a circle while the molds arerotated around a reference axis. In this talk, we will present the
instrument design challenges as well as preliminary results.

10023-18, Session 3

An automatic large-scale 3D coordinate
measurement system based on vision
guidance
Zili Zhang, Academy of Opto-Electronics, CAS (China);
Guanghua Wu, Hefei Univ. of Technology (China);
Qiyue Wang, BeiHang Univ. (China); Yan Zhang, Beijing
Information Science & Technology Univ. (China); Weihu
Zhou, Academy of Opto-Electronics, CAS (China)
An automatic large-scale 3D coordinate measurement system
based on vision guidance is presented. With a high-accuracy
total station accomplishing the basic coordinate measurement, acamera mounted on the total station is used to guide it to aim at
the target in the measuring field. The optical axis of the camera
is set to coincide with the collimation axis of the total station
so that the position of the principle point coincide with theposition of the telescope reticle of the total station in the image
obtained by the camera. Calibration is performed to calculate
the relationship between the angular deviation of the collimation
axis from the target and the pixel deviation of the target from thereticle. When the target is in the viewing field of the camera, theimage processing system can identify it automatically and thenangles for the total station to move horizontally and verticallyto aim at it can be calculated according to the pixel difference
between the target and the principle point. Then the total
station will automatically aim at the target and accomplish themeasurement automatically. Thus high-accuracy non-contact
measurement can be accomplished without additional effort
for targeting. The results show that the measurement system
can realize automatic large-scale measurement precisely andefficiently which provides an efficient approach for solving
automatic large-scale measurement problems.

10023-19, Session 3

Spatial intensity correlation properties ofscattered optical vortices
Salla G. Reddy, The Univ. of Electro-Communications(Japan); Ravindra Pratap Singh, Physical Research Lab.
(India)The intensity correlation length of an optical field is now playing
an important role in enhancing the resolution. Here, we control
the spatial coherence properties of a scattered field by changing#PhotonicsAsia

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Conference 10023: Optical Metrology and Inspection
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the mode of the input beam, the area of illumination as well as
the propagation distance. We generate the higher order opticalvortices and scatter them through a ground glass plate. We
focus the input beam on the ground glass using a lens in order
to control the size of the illuminated beam. Then, we analyze thespatial intensity correlation properties of the recorded speckle
patterns. The correlation studies are performed using Matlab. We
find that the intensity correlation length decays faster with theincrease in the order of the vortex. We also determine the change
in intensity correlation length as a function of propagation
distance, area of illumination and the order of an optical vortex.
We present the corresponding experimental as well as the
supported numerical results.

10023-20, Session 3

Fast in-situ tool inspection based on
inverse fringe projection and compact
sensor heads
Steffen Matthias, Markus Kästner, Yinan Li, Eduard
Reithmeier, Leibniz Univ. Hannover (Germany)
Inspection of machine elements is an important task inproduction processes in order to ensure the quality of produced
parts and to gather feedback for the continuous improvement
process. A new measuring system is presented, which is capableof performing the inspection of critical tool geometries, suchas gearing elements, inside the forming machine. To meet theconstraints on sensor head size and inspection time imposedby the limited space inside the machine and the cycle timeof the process, the measuring device employs a combinationof endoscopy techniques with the fringe projection principle.
Compact gradient index lenses enable a compact design ofthe sensor head, which is connected to a CMOS camera and aflexible micro-mirror based projector via flexible fiber bundles.
Using common fringe projection patterns, the system achieves
measuring times of less than five seconds. To further reduce thetime required for inspection, the generation of inverse fringe
projection patterns has been implemented for the system. Inverse
fringe projection speeds up the inspection process by employing
object-adapted patterns, which enable the detection ofgeometry deviations in a single image. Two different approaches
to generate object adapted patterns are presented. The first
approach is based on a virtual master geometry in the form ofa CAD file with tolerance specifications and a ray-tracing modelof the measuring system. The second approach uses a reference
measurement of a manufactured tool master to generate
the inverse pattern. Following the description of the patterngeneration process, the image processing steps required forinspection are demonstrated on captures of gearing geometries.

10023-21, Session 3

Numerical simulation research andapplications on scatter imaging of surface
defects on optical components
Huiting Chai, Yongying Yang, Zhejiang Univ. (China);
Pin Cao, Hangzhou Zernike Optical Technology Co., Ltd.
(China); Chen Li, Fan Wu, Yihui Zhang, Haoliang Xiong,
Zhou Lin, Kai Yan, Wenlin Xu, Dong Liu, Jian Bai, Yibing
Shen, Zhejiang Univ. (China)

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10023-22, Session 4

Plane stitching optical testing in
manufacturing workshop (Invited Paper)
Yingjie Yu, Shanghai Univ. (China); Xin Wu, Shanghai Univ
(China)Subaperture stitching is an effective technology to overcome
the limitation of conventional large aperture interferometers.
The combination of stitching and in-situ measurement
in manufacturing workshop will be an efficient testing
method for fabrication of large optical flat, but still difficultand challengeable. The environmental disturbance is themost troublesome. Commonly commercial phase-shifting
interferometers are not suitable for the vibrating environment.
An in-situ stitching measurement system has been built to
supporting the use of grinding machine, which contain dynamic
interferometer, marble gantry, precision guide and softwaresystem. The dynamic interferometer is mounted in a downlooking configuration on the gantry, which could close togrinding position during measurement and away from it whenprocessing. The software system could scheme the number andposition of the subapertures and control the interferometer toscan them automatically. Meanwhile the data could be stitched
together and reconstruct the full surface of tested flat. In thisprocessing, the systemic error from interferometer, the random
noise from the vibrating environment and the alignment
error from the mechanical guide have been analysed andcorresponding restrained methods have been proposed by somesimulation and experiment. It has been verified that the testing
range of this in-situ stitching measurement system could up to
1200mm?450mm, and flatness accuracy is better than 0.7?m.

10023-23, Session 4

Spin Hall effect of light applied in opticallinear scale
Yasuhiro Mizutani, Kazunori Ueda, Yasuhiro Takaya, Osaka
Univ. (Japan)

The principle of microscopic scattering dark-field imaging (MSDFI) is adopted in surface defects evaluation system (SDES)
for large fine optics. However, since defects are of micron or
submicron scale, scattering imaging cannot be described simply
by geometrical imaging. In this paper, the electromagnetic
simulation model for microscopic scattering imaging, established114

on the basis of vector diffraction theory and Finite-Difference
Time-Domain (FDTD) method, is used to study the scatter lightintensity distribution of rectangular and triangular defects withdifferent sizes in simulations. Standard defects on the criterionboard are evaluated by SDES to study their grayscale distribution
in experiments. Both the simulation and experiment results
are in good agreement. Because of the existence of diffraction
limit, scatter light intensity distributions of micron-scale defects
broaden to different degrees and also have difference in curve
shape. Scatter light intensity distributions of rectangular defects
are might in Gaussian or double-Gaussian shape while those oftriangular defects are might in Gaussian or epsilon-type shape.
Different width extraction methods are adopted in terms ofdifferent curve shapes. Double-Gaussian fitting is applied to
double-Gaussian shape and threshold segmentation is applied
to Gaussian and epsilon-type shape. In terms of scatter lightintensity distributions of Gaussian shape, severe broadening
might lead to confusion and misjudgment, so multiple parametersbesides threshold segmentation should be introduced to extract
actual width. The research findings presented in this paper
provide significant theory references for defect calibration in
optical manufacturing and inspection.

We propose a new concept of a linear scale to detect scale
displacement by using the spin Hall effect of light (SHEL). The
SHEL is a phenomena about a correlation between a spin angularmomentum and an orbital angular momentum of light. When thelinear polarized light reflects on a surface of a dielectric media,
the SHEL divides the light into a right and a left circular polarized

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
light and gives a slightly position changing of the reflected lightabout sub-10-nm scale which can be detected by a techniqueas the weak measurement. On the other hand, it is necessary
to prepare a main scale of a linear scale. We attempt to apply
carbon nano tube (CNT) for the scale. It was shown that the CNT
exhibited giant circular dichroism. By reflection on a dielectricsurface aligned the CNT as a scale, a left circular light of thereflected light generated by the SHEL is absorbed and amountof an optical absorption depends on a position of the CNT. In
this paper, as a first attempt, we have measured the SHEL of a
BK-7 glass plate by detecting a distance of two spitted lights
via the weak measurement. As a results, distance of two beams
generated by the SHEL was about 80nm and further results on
the displacement dependency are presented and discussed.

10023-24, Session 4

Accurate reconstruction in measurementof microstructures using digitalholographic microscopy
Xiaolei Zhang, Xiangchao Zhang, Min Xu, Fudan Univ.
(China)Micro-structured components with salient geometrical featuresdesigned to provide a specular function are widely used in thefield of precision engineering. The measurement of their surface
topographies has become an important issue. Due to the limited
ability of conventional laser interferometry, digital holographic
microscopy has attracted intensive attention for its capability ofmeasuring complex surfaces. However, speckles are inevitablein the recorded interferometric patterns, thereby polluting thereconstructed surface topographies. Thus speckle reduction
comes to be critical for improving the measurement accuracy.
In this paper, a phase-shifting Mach-Zehnder interferometeris built to realize the in-axis digital holographic microscopy.
The anti-aliasing shift-invariant contourlet transform (ASCT)
is used for reconstructing the measured surfaces. By avoiding
subsampling in the scale and directional filtering schemes,
the frequency aliasing and phase distortion can be effectively
solved, consequently overcoming severe degradation of themeasurement quality.
Experimental results of the ASCT reconstruction are compared to
the results of Fresnel integration and Fresnelet on the aspects offeature preserving and speckle removal. The experiments showthat the Fresnel reconstruction leaves conspicuous speckles
and causes image artifacts. Fresnel-wavelets would destruct
curved features. On the contrast, as contours between piecewise
continuous sections have sparse representations in the transformdomain of ASCT, then speckles can be recognized and removed
straightforwardly. Therefore the proposed method has excellent
performance in reconstructing structured surfaces.

10023-25, Session 4

Tip/tilt-compensated through-focus
scanning optical microscopy
Jun Ho Lee, Jun Hyung Park, Kongju National Univ. (Korea,
Republic of)Through-Focus Optical Microscopy (TSOM), proposed andmostly developed by Dr. Ravikiran Attota and his group at NIST,
has been demonstrated to be utilized for 3D inspection andmetrology with nanometer scale lateral and vertical sensitivity
matching a scanning electron microscopy. However, there havebeen sensitivity and instability issues in acquiring throughfocus images since TSOM 3D information is indirectly extracted
from differentiating a target TSOM image from reference TSOM
images. Ryabko proposed motion-free TSOM scanning using the

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chromatic aberration in an imaging optical system and a tunable
light source and taking consideration of optical aberrations of
the measurement setup into the TSOM reference library buildup.
However, we found that both the previous methods still arevulnerable to mechanical or optical instability during z-axis
through-focus scanning process. We are currently forming a
research consortium consisting of four universities (Kongju
National Univ., Seoul Univ., Korea Univ., Incheon National Univ.)
for studying co-technologies for developing develop in-line TSOM
inspection & metrology tools. This paper presents herein two
tip/tilt compensated TSOM optical acquisition methods appliedwith adaptive optics, which are currently under construction. The
first method simply adopts a tip/tilt mirror with a quad cell in a
simple closed loop while the second method adopts a high-orderdeformable mirror with a Shack-Hartmann sensor. The second
version is able to correct high-order residual aberrations as wellas performing through-focus scanning without z-axis movement.
Currently we are building a prototype of the first model and thefirst measurement results will be presented.

10023-26, Session 4

The total spectral radiant flux calibration
using a spherical spectrometer at National
Institute of Metrology China
Weiqiang Zhao, Hui Liu, Jian Liu, National Institute ofMetrology (China)
At present day, in the field of lighting the incandescent lamps arephasing out. The solid state lighting products, i.e. LED, and therelated market are developing very fast in China for its promising
application, due to the energy-saving and the colorful features.
For the quality control and the commercial trade purpose, it
is highly necessary to measure the optical parameters of LED
light sources with a fast, easy and affordable facility. Therefore,
more test labs use the spherical spectrometer to measure LED.
The quasi- monochrome of LED and the V(lambda) of silicon
photodetector mismatch problem is reduced or avoided, because
the spectral total radiant flux (STRF) is measured, and all the
optical parameters are calculate from the STRF. In such a way, thespherical spectrometer calibration requires STRF standard lamps
instead of the traditional total flux standard lamps. National
Institute of Metrology China (NIM) has studied and developed thefacilities for STRF measurement and provides related calibration
services.
This paper shows the STRF standard lamp calibration procedureusing a spherical spectrometer in every-day calibration and its
traceable link to the primary SI unit at NIM. The sphere is of
1.5 m diameter, and installed with a spectrometer and a silicon
photodetector. It also shows the detail of data process, such as
the spectral absorption correction method and the calculationof the result derived from the spectral readings. The STRF
calibration covers the spectra range of 350 nm to 1050 nm, witha measurement uncertainty of 1.8% ~ 3.6% (k=2).

10023-9, Session Post

Error analysis of a self mixing
interferometry operated near relaxation
oscillation region
Yuanlong Fan, Yanguang Yu, Jiangtao Xi, Qinghua Guo,
Roger A. Lewis, Univ. of Wollongong (Australia)
Self-Mixing Interferometry (SMI) is an emerging non-contact
sensing technique for the measurement of various metrologicalquantities. An SMI system is composed of a laser diode (LD) witha photodiode (PD) packaged at the rear of the LD, a lens and an
external target. When the external target moves, a small portion#PhotonicsAsia

115

Conference 10023: Optical Metrology and Inspection
for Industrial Applications IVof light reflected re-enters the internal cavity of the LD, leading
to the modulation of the LD output power. The modulated power
is detected by the PD as an SMI signal, which can be used forextracting useful information and its accuracy strongly depends
on the shape of the SMI signal. It is usually desired that an SMI
system operates in a stable mode, in which case the SMI signal
contains sinusoidal-like fringes or sawtooth-like fringes. However,in some cases, it is inevitably that the system will become
unstable and the SMI signal becomes distorted which could
induce significant measurement errors. This is due to the limit of
the bandwidth of the PD, and the SMI signal detected is actually adistorted version of a waveform containing a very high frequency(usually 2-4GHz). In this paper, in order to achieve a reliable SMI
system in the unstable region, the measurement error is analyzed
by investigating the influence of the bandwidth of the PD on the
shape of SMI signals via numerical simulations on the well known
Lang and Kobayashi (LK) equations. The results presented in thispaper are helpful for designing an accurate SMI system operated
in the unstable region.

10023-10, Session Post

Bin Liu, Ginu Rajan, Yanguang Yu, Jiangtao Xi, Qinghua
Guo, Jun Tong, Univ. of Wollongong (Australia)
Fiber Bragg grating (FBG) based sensors can be utilized invarious applications ranging from strain to temperature to
vibration measurements. Acoustic emission (AE) is a wellknown technique in detecting stress/strain waves generated bystructural defects, allowing continuous structural monitoring
during the service life of an infrastructure. However, measuring
AE signals using FBGs is always a challenge as the strain
induced by the high frequency dynamic signal will be in thenano or pico strain levels. On the other hand, as a non-contact
sensing technique, self-mixing interferometry (SMI) has been
exploited intensively for the measurement of various metrologicalquantities because of the compact structure and quasiinterferometric resolution. This paper combines the techniquesabove and devises a fiber optic strain sensor based on SMI and
FBG for AE measurement. Compared to typical SMI systems,
what makes it different in an FBG-SMI system is that, the strengthof the reflected signal will vary as the FBG vibrates, whichmakes the feedback strength variable. In this work, firstly, themathematical model of SMI has been modified by considering thevariable feedback strength, and simulations have been conductedbased on the modified model. From this model, SMI signals
carrying features of strain applied to the FBG are observed andthe estimated dynamic strain sensitivity is about 0.1µ? which
is suitable for micro-crack monitoring in structures. Then, an
experimental system for AE measurement has been establishedto verify the simulation results. The FBG-SMI sensor presented
in this paper combines the advantages of fiber FGB and SMI,
contributing to a novel system which can be used to measurecrack-induced AE signals to enable the early detection of failureof structures.

10023-52, Session Post

Remote sensing multiple hazardous andtoxic gases by passive open-path FTIR

Dimensional measurement of micro parts
with high aspect ratio in HIT-UOI

In recent years open-path FTIR systems (active and passive) havedemonstrated great potential and success for environment gas·

Micro parts with high aspect ratio have been widely used indifferent fields including aerospace and defense industries, while
the dimensional measurement of these micro parts becomes achallenge in the field of precision measurement and instrument.
To deal with this contradiction, several probes for the micro parts
precision measurement have been proposed by researchers inCenter of Ultra-precision Optoelectronic Instrument (UOI), Harbin
Institute of Technology (HIT). In this paper, optical fiber probeswith structures of spherical coupling(SC) with double opticalfibers, micro focal-length collimation (MFL-collimation) and fiber
Bragg grating (FBG) are described in detail. After introducing
the sensing principles, both advantages and disadvantages ofthese probes are analyzed respectively. In order to improve
the performances of these probes, several approaches areproposed. A two-dimensional orthogonal path arrangement is
propounded to enhance the dimensional measurement abilityof MFL-collimation probes, while a high resolution and response
speed interrogation method based on differential method is used
to improve the accuracy and dynamic characteristics of the FBG
probes. The experiments for these special structural fiber probes
are given with a focus on the characteristics of these probes,
and engineering applications will also be presented to prove theavailability of them. In order to improve the accuracy and theinstantaneity of the engineering applications, several techniques
are used in probes integration. The effectiveness of these fiber
probes were therefore verified through both the analysis andexperiments.

10023-54, Session Post

Simulation of out-of-plane displacement
measurement using vortex beam: onthe base of liquid crystal spatial light
modulator
Haibin Sun, Shandong Normal Univ. (China) and Taishan
Univ. (China); Ping Sun, Shandong Normal Univ. (China)

Zhan Lu, Univ. of Chinese Academy of Sciences (China);
Xiao Zuo Dai, Univ. of Chinese Academy of Science(China); Bei Ma, Univ. of Chinese Academy of Sciences(China)SPIE Photonics Asia

10023-53, Session Post

Hong Dang, Jiwen Cui, Kunpeng Feng, Junying Li, ShiYuan
Zhao, Haoran Zhang, JiuBin Tan, Harbin Institute ofTechnology (China)

FBG-based fiber self-mixing sensor for
acoustic emission measurement

116

pollution remote detection as its higher spectrum resolution, alarge range of spectrum and high spectral flux. However, there
are few reports about FTIR used to detect hazardous and toxic
gases in the case of terrorist acts and chemical accidents in
those places for surveillance, such as public stadium and subway
or train station and highway or chemical plants. In those places,
passive infrared is an emerging method for remote sensing of
hazardous and toxic gases and FTIR is an ideal instrument togive an early warning and situation assessment, which is helpful
for emergency response personnel at site to take appropriate
measures to protect passengers, works and residents. Passive
open-path FTIR remote sense the target gases spectrum dueto the temperature difference with backgrounds. Retrieving themeasured spectrum we can get the gas column concentrationand species by contrast to the standard gas library.

Electronic speckle pattern interferometry (ESPI) is a useful
optical technique for deformation measurements. In ESPI
experiment, object beam and reference beam are always planelight. With the development of optical vortices research, theplane light which usually used as object light or reference light
can be replaced by vortex beam. Vortex beam can be generated
by a reflective liquid crystal spatial light modulator (LC-SLM)

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
which added in the optical path. The gray image of fork hologramis displayed on the screen of LC-SLM, and the generated vortex
beam is used as object light or reference light in out-of-plane
displacement measurement. The interference intensity of theout-of-plane displacement is calculated and analyzed, and theinterference fringe patterns are simulated before and after theobject deformation. By phase shifting method and unwrapping,
the three-dimensional distribution of phase difference isobtained. The simulation results demonstrate the efficacyof the proposed method for the out-of-plane displacement
measurements. Vortex beam can become a powerful method in
micro-measurements.

10023-55, Session Post

Super-resolution confocal microscopy
based on radially-polarized beams andpupil filtering
Zhehai Zhou, Beijing Information Science and Technology
Univ. (China); Jiaxing Liu, Lianqing Zhu, Beijing
Information Science & Technology Univ. (China)High spatial resolution optical measurement methods andtechniques have become a major research topic in modern
measurement areas. Some super-resolution imaging methods
have been proposed to meet the urgent need of high resolution
optical measurement, including 4Pi confocal microscopy,
structured illumination microscopy (SIM), stimulated emission
depletion (STED), Stochastic optical reconstruction microscopy(STORM), photo activated localization microscopy (PALM) andfluorescence photo-activation localization microscopy (FPALM).
However, to some extent, these methods are complicated,
expensive or cumbersome. So we propose a super-resolution
imaging scheme based on a standard confocal microscopy,
and radially polarized beams and pupil filtering are used in thescheme by use of the unique focusing properties of radiallypolarized beams and optical shaping technology. The 3D opticaltransfer function (OTF) and point spread function (PSD) are
derived based on vector diffraction theory, and some simulation
results are presented to verify the feasibility of super-resolution
imaging. Meanwhile, the effects of system structure parameters,such as the size of detector, size of pin-hole, and their position
deviations on imaging performances are analyzed.

reflect the optical properties of an FG diffuser, may be used to
optimally select a diffuser for a particular optical experiment or
numerical calculation.

10023-57, Session Post

A colorful codification method forstructured light measurement based on
the hue of single image
Wei Yin, Haihua Cui, Nanjing Univ. of Aeronautics andAstronautics (China); Chenbo Zhang, Nanjing University of
Aeronautics and Astronautics (China); Xiaosheng Cheng,
Dawei Li, Nanjing Univ. of Aeronautics and Astronautics(China)This paper presents an effective optical metrology by employing
the HSI color space (hue, saturation and intensity) to form thecolor pattern for reconstructing an object with one-shot image.
The color pattern consisting of three sinusoidal fringes withdifferent phase steps encoded in RGB channels is projected by adigital video projector then the deformed pattern is recorded bya color CCD camera. The captured color fringe is transformed to
HSI color space and separated into hue, saturation and intensity
components. As the hue component of the deformed fringe
pattern changes in a linear trend, it is regarded as phase quantity
to reconstruct 3D profile with triangulation principle efficiently
and accurately. For some complex surface, the discontinuities
parts mainly caused by spatially isolated surfaces, height steps
or shadow will induce various error points in the 3D profile oftesting object. It is considered as one of the remaining challenges
faced by phase shifting methods. As these invalid parts do notcontain the pure color information, intensity and saturation
components are applied to establishing a binary map to segment
these invalid parts before reconstruction procedure. Besides,
as some factors will affect the linearity of hue, such as gamma
error and color crosstalk, an effective and simple compensatingprocedure is proposed to correct the hue error. Experiments are
conducted to verify the feasibility of the developed methodology.
In conclusion, this method, this method is proposed to measure
3D shape with one snapshot color fringe pattern which can avoid
phase discontinuities.

10023-58, Session Post
10023-56, Session Post

Experimental investigation of correlation
between surface amplitude parameters offrosted glass diffuser and size of polishinggrit
Dong Wei, Masato Aketagawa, Tomoya Katagiri, Nagaoka
Univ. of Technology (Japan)
Frosted glass (FG) diffusers are used for various purposesin optical experiments and are qualitatively classified basedon the particle size of the grit used to polish them. Moreover,their surface topographies are known to affect their opticalability. However, a quantitative relationship between the surface
topography (especially the surface amplitude parameters) andthe polishing grit size is yet to be established. In the present
study, a contact-type surface roughness measurement instrument
was used to measure the surface amplitude parameters of avariety of commercial FG diffusers. The determined parameters,
which are defined in ISO 4287-1997, were then compared withthe root mean square of the grit size and the quantitative
relationships were investigated. The parameters that were moststrongly correlated with the root mean square of the grit size
were identified. The established relationships, which statistically

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Follow us on:Corner detection and sorting method
based on improved Harris algorithm incamera calibration
Ying Xiao, Yonghong Wang, Xizuo Dan, Anqi Huang, Yue
Hu, Hefei Univ. of Technology (China); Lianxiang Yang,
Hefei Univ of Technology (China) and Oakland Univ.
(United States)
In traditional Harris corner detection algorithm, the appropriate
threshold which is used to eliminate false corners is selectedmanually. In order to detect corners automatically, an improved
algorithm which combines Harris and circular boundary theory ofcorners is proposed in this paper. Firstly, a small threshold is set
in order to make sure all the correct corners will not be missed.
Secondly, traditional Harris algorithm is used to detect integer
corner coordinates and the Forstner algorithm is used to revise
the results and obtain accurate sub-pixel corner coordinates.
Thirdly, by using the circular boundary theory of corners, false
corners within the chessboard pattern of the calibration plate
can be eliminated automatically. Moreover, a corner sorting
method based on an improved calibration plate is proposed.
The plate is designed by adding three circles into the black andwhite chessboard pattern. Using the centers of three circles, a#PhotonicsAsia

117

Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
new coordinate system is established. According to the distance
between corners and the new origin point, background corners
are eliminated and all the remaining corners are sorted in order.
As the location of corners in new system doesn’t change with therotation of plate, sorting result can adapt to complex backgroundand free rotation of the calibration plate. The final cornercoordinates can be used in calibration calculation and all the
intrinsic and extrinsic parameters can be obtained. Experimentresults show that the proposed algorithms can eliminate all false
corners and sort remaining corners correctly and automatically.

different methods. Experimental results suggested that our
method achieve the same precision of the BA method but be
more efficient. Respect to the methods that traditionally takeDirect Linear Transformation (DLT) to get initial solution, ourmethod is more robust and under the condition of poor camera
position configuration it is still able to converge and calculate
positions of the interested points. We also conducted real image
experiment and obtained satisfactory measurement result.

10023-59, Session Post

Influence of irradiance non-uniformity
on IV performance test of photovoltaic
modules

An onsite non-contact dynamic angle
metrology system based on stereo vision

Junchao Zhang, Limin Xiong, Haifeng Meng, Yingwei He,
Bifeng Zhang, National Institute of Metrology (China);
Chuan Cai, Kejia Zhang, Beijing Institute of Technology(China)Jiping Guo, Shenzhen Univ. (China) and Shenzhen
Academy of Metrology and Quality Inspection (China);
Jiping Yu, Shenzhen Academy of Metrology and Quality
Inspection (China); Xiang Peng, Shenzhen Univ. (China);
Ameng Li, Shenzhen Academy of Metrology and Quality
Inspection (China); Xiaoli Liu, Shenzhen Univ. (China)
Angle metrology is an important content in the field of industrial
measurement. And the non-contact metrology method for onsite dynamic angle measurement is becoming more and moredemanded recently. Here we present a dynamical large swing
angle and attitude angle metrology method base on stereo
vision. Firstly, image sequences of the object attached with point
markers are captured synchronously by a calibrated dual camera
stereo system in real time. Secondly, the 3D coordinates of themarkers recorded during the moving cycle are reconstructed.
Finally, the fitted motion curve of the object can be obtainedwith aid of 3D coordinates of the markers, and then the angle
variation is calculated out by a specific algorithm. In this method,the off-plane error of the swing arm (or rotation plate) can also
be obtained. A set of measurement experiments have been
implemented, and the results show that the presented method
is rather suitable for measuring the dynamic angle on-site withadvantage of on-contact . And the measurement error of thesystem can reach to ±0.02°for swing angle measurement and±0.12 °for attitude angle measurement, which can satisfy the
dynamic angle metrology requirement in many cases.

10023-60, Session Post

3D measurement and camera attitude
estimation method based on trifocal
tensorShengyi Chen, Haibo Liu, Linshen Yao, Qifeng Yu, National
Univ. of Defense Technology (China)
An efficient and robust 3D measurement method based on
trifocal tensor is proposed in this paper, which only employs theintrinsic parameters and positions of three cameras to perform
3D measurement and camera attitude estimation simultaneously.
The initial trifocal tensor among the three views is obtainedby using heteroscedastic errors-in-variables (HEIV) estimatorand the initial relative poses of the three cameras is acquiredby decomposing the tensor. Further the initial attitude of thecameras is obtained with knowledge of the three cameras’
positions. Then the camera attitude and the interested points’
image positions are optimized according to the constraint oftrifocal tensor with the HEIV method. Finally the spatial positionsof the points are obtained by using intersection measurement
method. Compared with the traditional method based on Bundle
Adjustment (BA), we inspected the performance of our proposal
method. We took advantage of several sets of simulation data
to investigate the location accuracy and computing time of the118

SPIE Photonics Asia·

10023-61, Session Post

The effect of irradiance non-uniformity on IV performance ofphotovoltaic (PV) module is analyzed. The theoretical calculation
results and the experimental results are in good agreement. The
irradiance, irradiance uniformity and irradiance stability testing
device is established. The accurate measurement of irradiancecharacteristics of solar simulator is realized. Through the actual
test of solar simulator irradiance distribution and the theoretical
calculation of the measurement results, the irradiance distribution
and the monitor cell position effect on IV performance testingof PV modules is analyzed. The analysis result is beneficial toevaluating the performance of the solar simulator.

10023-62, Session Post

Virtual-stereo fringe reflection technique
for specular freeform surface testing
Suodong Ma, Soochow Univ. (China); Bo Li, Nanjing
Institute of Astronomical Optics & Technology (China)
Due to their excellent ability to improve the performance of
optical systems, free-form optics have attracted extensive
interest in many fields, e.g. optical design of astronomical
telescopes, laser beam expanders, spectral imagers, etc. However,compared with traditional simple ones, testing for such kind of
optics is usually more complex and difficult which has been beinga big barrier for the manufacture and the application of these
optics. Fortunately, owing to the rapid development of electronic
devices and computer vision technology, fringe reflection
technique (FRT) with advantages of simple system structure, highmeasurement accuracy and large dynamic range is becoming a
powerful tool for specular free-form surface testing. In order toobtain absolute surface shape distributions of test objects, two or
more cameras are often required in the conventional FRT whichmakes the system structure more complex and the measurement
cost much higher. Furthermore, high precision synchronization
between each camera is also a troublesome issues. To overcome
the aforementioned drawback, a virtual-stereo FRT for specularfree-form surface testing is put forward in this paper. It is able
to achieve absolute profiles with the help of only one single
biprism and a camera meanwhile avoiding the problems of stereo
FRT based on binocular or multi-ocular cameras. Preliminary
experimental results demonstrate the effectiveness of the
proposed technique.

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV

10023-63, Session Post

10023-65, Session Post

Digitization and visualization of virtual
cultural heritage

Evaluation of 3D displacement
components by combining DSCM with
ESPI

Ameng Li, Jiping Guo, Jiping Yu, Shenzhen Academyof Metrology and Quality Inspection (China); Yong Yao,
Harbin Institute of Technology Shenzhen Graduate School(China)In recent years, virtual cultural heritage generated by optics andcomputer graphics methods has become an active researchsubject that has drawn much attention and interest from
communities of optical engineering, computer science andcultural heritage around the world. In this talk, we are going tobriefly introduce some of typical research projects regarding
virtual heritage undertaken and ongoing in the North America,
European Community (EC), Japan and China, from which we cansee that the technology of 3D scanning and interaction with highquality graphics plays a central role in virtual heritage. Thereafter
we present a new optics-graphics platform for automatically
digitizing and presenting the virtual cultural heritage. This
platform is designed with a strategy of using an optical scanning
network arranged as one-dimensional array consisted of a set
of 3D node-sensors. The 3D sensor array works in conjunction
with a motorized controlled turntable in our proposed platformarchitecture. With this dedicated design, we are able to digitize
complete 3D virtual heritage with complex geometry andtopology while the 3D scanning pipeline, including the acquisition
and registration of multiple range images can be implemented ina fully automatic fashion. Furthermore, the texture mapping andblending are also applied for generating photorealistic 3D graphic
models of virtual cultural heritages. The architecture design of
instrument prototype for scanning hardware and the framework
for reconstruction and interaction software are described inthis presentation. Furthermore, some of experiment results for
digitization and visualization of virtual cultural heritage areshown to demonstrate the effectiveness of proposed platform.

Ping Sun, Kai Shi, Shandong Normal Univ. (China);
Mingyong Sun, Shandong Xiehe Univ. (China); Haibin Sun,
Shandong Normal Univ. (China) and Taishan Univ. (China)
Three dimensional (3-D) deformation measurement of an
object has always been required in the evaluation of material
properties. By comparing the changes of the gray intensity ofan object surface before and after deformation Digital Speckle
Correlation Method (DSCM) obtains in-plane deformation. But
strict limitations are taken in measurement such as those thetest object surface must be flat, the speckle patterns have to be
fully developed, the modulation transfer function of the camera
must be taken into consideration, and carefully adjusted focus
is needed. In order to increase the sensitivity of the in-plane
displacement components, the in-plane and out-of plane ESPI
interferometers are combined for 3-D evaluation of deformations.
The combination can obtain three components of displacement
directly without computation. But it is too complicated in
optical arrangement, which affects the measurement precision.
A method for 3-D deformation measurement is presented by
combining DSCM with Electronic Speckle Pattern Interferometry(ESPI). The combination is completed based on a typical ESPI
system, in which the reference light is controlled to turn on or
shut down. The in-plane displacement components are obtainedby using DSCM when the reference light is shut. A phase shifting
ESPI is formed when the reference light is used, which canbe used for the measurement of the out-plane displacement
component. A typical three-point-bending experiment iscompleted. Experiment results show that the three displacement
components can be obtained by the combination effectively.

10023-66, Session Post
10023-64, Session Post

A simple phase-shift ESPI for 3D
deformation measurement
Ping Sun, Xinghai Wang, Shandong Normal Univ. (China);
Haibin Sun, Shandong Normal Univ. (China) and Taishan
Univ. (China)
Electronic speckle pattern interferometry (ESPI) is a widely
employed technique for static and dynamic deformation
measurements. There have been many techniques reported tomeasure the three dimensional displacement of an object. The
complicated optical arrangement affects the measurement
precision. Give attention to the sensitivity of the displacement
components and the simplicity of the optical setup, a simple
setup for 3-D deformation measurement is offered. In thescheme a novel Cube Beam-Splitter, called Non-Cube BeamSplitter (NCBS), is used for 3-D phase-shift ESPI. By using the
NCBS lights from a tested object and lights from a reference
surface can be combined and then interfere each other on a
CCD camera when a laser beam illuminate the test object andthe reference surface simultaneously. When three laser beams
illuminate the test object at different incident angles respectively
before and after deformation, three interference fringe patterns
are formed. Then three phase maps corresponding to threelasers can be calculated by using phase-shift, by which three
displacement components are completed. The principle ofthe method is presented and proved by a typical three-point
bending experiment. Using the NCBS presented and the 3-D
optical setup with phase shifts, three phase components can be
determined effectively. The new setup is simple, less sensitive tosurroundings.

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The calibration of specular gloss metersand gloss plates
Tiecheng Li, Lei Lai, Leibing Shi, Dejin Yin, FangshengLin, Ming Xia, Biyong Huang, Shanghai Institute of
Measurement and Testing Technology (China)
Specular gloss is the perception by an observer of the mirror-likeappearance of a surface. The definition of specular gloss is theratio of luminous flux reflected from an object to that reflectedfrom a gloss reference standard in the specular direction for a
specified reflection angle and specified aperture angles of source
and receptor. Specular gloss is usually measured by a gloss
meter, which can be calibrated by a group of gloss plates ranging
from high to matt gloss values according to ISO 2813:2014 (Paints
and varnishes – Determination of gloss value at 20°, 60° and85°) and JJG 696-2002 (verification regulation of specular gloss
meters and gloss plates). The characteristics of a gloss meter
include measuring range, resolution, stability, zero error, errorof indication, uniformity of illumination, match between lightsource and photo detector. The characteristics of a gloss plateinclude gloss value, roughness and spectral transmissivity of ahigh gloss plate, spectral reflectivity of a ceramic gloss plate,annual variation. Experiments have been performed on different
kinds of gloss meters and gloss plates. The results indicate thatstability of indication may exhibit significant differences among
various gloss meters, which will seriously affect the verification
result. Similar to gloss meters, verification procedure of gloss
plates unavoidably is influenced by roughness and spectral
transmissivity of a high gloss plate, spectral reflectivity of aceramic gloss plate. Therefore, calibration of both gloss meters#PhotonicsAsia

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
and gloss plates should be carefully performed according to theverification regulation in order to reduce the measurement error.

10023-67, Session Post

Numerical calibration of laser line
scanning system with multiple sensors forinspecting cross-section profiles
Jingbo Zhou, Yuehua Li, Fengshan Huang, Lijian Liu, Hebei
Univ. of Science and Technology (China)
Laser line scanners (LLSs) have gained more and more
applications in industry. An interested profile can be easily
obtained through the analyses of laser-object intersection stripe.
But one sensor is inadequate to get a closed cross-section
profile due to the obstacle of the laser light. Thus, multiple LLSs
are integrated as a whole for profile inspection and a numericalcalibration method was also proposed. Firstly, the laser planes
from all the projectors were adjusted to coincide with the target
plane with the aid of a marked rectangular block. After that theorigin of the world coordinate frame was fixed at the centerof the up-corner calibration dot with its X and Y axis coincidewith the target plane. Each sensor camera captured an imageof the same target. The relationship between the pixel andthe world coordinates was established using an interpolation
method via the world coordinates of target dot centers and theircorresponding pixel coordinates. Such that the measured pointfrom all of the sensor cameras have a same world coordinate
frame and a closed cross-section profile can be achieved. This
proposed method neither need to establish the intrinsic, theextrinsic and the distortion models of the camera, nor needto solve the complex optimization equations to determine themodel coefficients. The factors affecting the measuring accuracy
were also analyzed. Finally, a cylinder and a rectangular block
were inspected and their cross-section profiles were successfully
obtained. The comparison with the measuring results fromthe coordinate measuring machine further validates the highaccuracy of the proposed method.

10023-68, Session Post

Uncertainty evaluation of ellipsometer:from instrumentation to material andapplication in Avogadro’s project
Wende Liu, Chi Chen, Qiming Fan, Chu Chu, National
Institute of Metrology (China)
As a flexible tool for characterizing optical and structuralparameters of thin film, ellipsometers have been widely employedin various fields including new-type thin film material such as
solar cells, OLED, and in-situ parameter control applications.
On the other hand, ultra sensitivity enables ellipsometry to be
used in avant-garde metrological problem of precise counting ofsilicon atoms in a macro sphere made of monocrystalline silicon,
which is one of the candidates for redefining Kg unit in the near
future. Sub-atom accuracy (about 0.1nm) is generally required formeasuring the several-nanometer-thick overlayer on the surface
of a highly polished Si sphere. The paper reviews the effort for
setting up a traceable ellipsometer with the uncertainty outlined
to include both instrumentation and material contributions. For
special consideration of the application in Avogadro’s project,some new uncertainties are considered.
It is for a long time, NIST’s standard reference material series
are used by users from all over the world. The ellipsometer set
up by NIST consists of only rotating polarizers, without phaseretarding elements, therefore eliminating possible error from theuncertainty of the phase retardance. The AOI is determined withhigh precision by high-resolution encoders. Therefore, the various

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angles that determine the (Psi, Delta) uniquely are all calibrated
in a traceable manner, which further ensures the traceability of(Psi, Delta).
The idea is applied to the Avogadro’s project, in which the
crystalline silicon atoms in a macro silicon sphere are counted
to give Avogadro’s constant, which is in turn used to define the
SI unit Kg with a desired relative uncertainty of 2E-8. The paper
investigates the use of ellipsometer to measure the outermost
silicon oxide layer, which contributes to both diameter andmass measurement results of the sphere, therefore resulting
in a relatively large contribution to the final uncertainty of
Avogadro’s constant. An uncertainty is outlined according to the
instrumentation analysis here, and future works are envisaged.

10023-69, Session Post

Dynamic 3D shape measurement based on
digital speckle projection and temporalsequence correlation
Ren Chao Xu, Sichuan Univ (China); Fangyan Zhou, Qican
Zhang, Sichuan Univ. (China)
Digital speckle correlation method, as one of opticalmeasurement methods, has been developing from 1980s. The
distributions of the speckle field on objects’ surface before andafter objects’ displacement or deformation are analyzed, andthen the values of displacement or deformation are obtained by
the statistical correlation method. Taking its advantage of nocontact, wide measuring range and simple optical setup, digital
image correlation method has been widely used in many fields
such as mechanics, biomedicine and so on.
Because of the non-periodicity and discrete nature, unnecessaryof phase unwrapping process, the digital image correlation
method shows significant advantages in 3D shape measurement.
Based on digital speckle temporal sequence correlation andspeckle projection, an experimental platform was built tomeasure the dynamic 3D shape measurement in this paper. The
frame rate of high-speed camera was set to acquire modulated
speckle patterns during quartz clock’s pointers’ walking.
Programming was written to implement the algorithm toreconstruct every motion of the clock’s pointers. Beyond that, a
simple Newton’s cradle was established, and the collision course
between three steel balls was reconstructed. These experimental
results show that the method can be used for dynamic 3D shapemeasurement, which has a better effect on the reconstruction of
objects with characteristics of steep variation, isolation and small
details.

10023-70, Session Post

A flexible new method for 3D
measurement based on multi-view image
sequences
Haihua Cui, Nanjing Univ. of Aeronautics and Astronautics(China)Three-dimensional optical measurement is a flexible method toacquire the data of objects. It has been widely applied in various
industries, aerospace, biomedical engineering, and so on. The
paper developed a new flexible and fast optical measurement
method based on multi-view geometry theory. At first, featurepoints are detected and matched with improved SIFT algorithm.
The Hellinger Kernel is used to estimate the histogram distanceinstead of traditional Euclidean distance, which is immunity to theweak texture image; then a new filter three-principle for filtering
the calculation of essential matrix is designed, the essential
matrix is calculated using the improved a Contrario Ransac
filter method. The position of the camera and 3D points arewww.spie.org/pa·

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
considered, Instead of choosing the reprojection error, the firstorder geometrical error is used to estimate the 3D measurement
error. Then, the essential matrix is calculated with the optimized
RANSAC algorithm. The RANSAC algorithm based on the A
Contrario thought is better to measure the reliability of the model
than the traditional method. One view point cloud is constructedaccurately with two view images; after this, the overlappedfeatures are used to eliminate the accumulated errors causedby added view images, which improved the camera’s position
precision, then the different view point cloud are transformed
to the same coordinate with different scale factor. At last, themethod is verified with the application of dental restoration CAD/
CAM, experiment results show that the proposed method is fast,accurate and flexible for tooth 3D measurement.

10023-71, Session Post

A robust real-time laser measurement
method based on noncoding parallel
multi-line
Chenbo Zhang, Nanjing Univ of Aeronautics andAstronautics (China); Haihua Cui, Wei Yin, Liu Yang,
Nanjing Univ. of Aeronautics and Astronautics (China)
Single line 3D measurement is the main method in traditional
3D hand-held laser measurement, whose reconstruction speed
is very slow and cumulative error is very large. Therefore, we
propose a rapid real-time 3D measurement method based onparallel multi-line. Two cameras and a laser that project multiple
laser lines are needed in this method. Firstly, we calibrate thesystem of the two cameras and the laser, obtaining intrinsic
parameters and spatial relations between the two cameras and3D laser plane equations. Secondly, we process the two images
that contain multi-line laser stripes shot by the the two cameras.
In order to match the multi-line laser stripes conveniently, weneed to refine them and then extract their centers accurately.
With the previous calibration results, we transform one points
on the left image laser stripe centers to the right image withtriangulation principle, and get a series of corresponding points
calling An. Then we find the polar lines of An on the right image,a series of intersection points calling Bn can be acquired by
the polar lines and laser stripes on the right image.Finally, we
compare the distance of An and Bn to get the correct match
point within the threshold value range we set. Through the abovemeasurement,we can find match points of other laser stripe
centers on the left image in turn. Experiments of this paper provethat this method is feasible, not only improve the scanning speed
greatly, but also increase the scanning area greatly, which canmeet the demand of more industrial measurement.

10023-72, Session Post

Experiments and error analysis of laser
ranging based on frequency-sweep
polarization modulation
Shuyuan Gao, Hefei Univ. of Technology (China); Rongyi
Ji, Weihu Zhou, Academy of Opto-Electronics, CAS(China)Frequency-sweep polarization modulation ranging method usesa polarization-modulated laser beam to determine the distanceto the target, the modulation frequency is swept and frequency
values are measured when transmitted and received signals are inphase, thus the distance can be calculated through these values.
This method gets a much higher theoretical measuring accuracy
than phase difference method for the prevention of phasemeasurement. However, actual accuracy of the system is limited

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because additional phase retardation occurs in the measuring
optical path when optical elements are imperfectly processed
and installed. In this paper, working principle of frequency
sweep polarization modulation ranging method is analyzed andtransmission model of polarization state in light path is built
based on the theory of Jones Matrix, additional phase retardationof ?/4 wave plate, PBS, and retro-reflector and their impact on
measuring performance is analyzed. Theoretical results show thatwave plate’s retardation error dominates the limitation of ranging
accuracy, while azimuth deviation of wave plate and PBS has little
influence on that, though retro-reflector can profoundly affectthe polarization state of the output beam, symmetry of such
effect to the beam can diminish the ranging error, so it is crucial
to ensure the light points to center of the reflector. According to
the system design index, element tolerance and error correcting
method of system is proposed, ranging system is built andranging experiment is performed. Experiential results show thatwith proposed tolerance and error correcting method, the system
can satisfy the accuracy requirement. The present work has a
guide value for further research about system design and error
distribution.

10023-73, Session Post

High-speed image acquisition technology
in quality detection of workpiece surface
Kaihua Wu, Wenjie Wang, Xuechao Sun, Hangzhou Dianzi
Univ. (China)
High-speed image acquisition technology has a great significanceto improve the effciency of the workpiece surface quality
detection, image quality directly affects the final test results.
Aiming at the high-speed image acquisition of workpiece surface
quality online detection, a workpiece image high-speed online
acquisition method was produced. A high-speed online image
acquisition sequence was designed. The quantitative relationshipbetween the positioning accuracy in the high speed online
image acquisition, motion blur, exposure time and the speedof workpiece was analyzed. The effect between the vibration
between transfer mechanism and workpiece was analyzed. Fast
trigger was implemented by photoelectric sensor. The accurate
positioning was implemented by using the high accuracy timedelay module. The motion blur was controlled by reducing theexposure time. A high-speed image acquisition system wasdesigned based on the high-speed image acquisition method.
The positioning accuracy was less than 0.1 mm, and the motion
blur was less than 1 pixel.

10023-74, Session Post

Research of dimension and density
measurement system for minor artifacts
Yu Gao, Chao Gao, Chongqing Univ. (China)
The measuring object is cylindrical pellets, the system detectspellets’ diameter and height with non-contacting mode, getting
quality through high precision electromagnetic balance, andthen the density can be calculated.The hardware part of themeasuring system consists of size and quality measurement
module. The size measuring module is made of CMOS image
sensor, GaNgreen LED,embedded image processing system andpower source. The system can get pellet’s 2-dimentionnal image
by light projection principle, then CMOS sensor convert theimage signal to electrical signal, so the pellet diameter and heightvalues can be obtained after analyzing and calculating.Monte
Carlo simulation methoddemonstrate that, the use of two sets ofeach other into 90 ° measuring device can obtain more accurate
size values.Quality measurement module is mainly composed ofhigh precision electromagnetic balance.The geometric densities#PhotonicsAsia

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
can be obtained by sing corresponding calculation formula after
software receive these data.

10023-75, Session Post

The research of weld defect detection
based on high precision displacement
sensor10023-78, Session Post

Study of angle measuring error
mechanism caused by rotor run-outs

Kelin Hu, Chao Gao, Chongqing Univ. (China)
Welding is one of the very common process in industrial
production. It is a kind of manufacturing process and technology
which joint mental or other thermoplastic materials by heating,high temperature or high pressure. Welding quality will directly
affect the final quality of workpiece. So during the welding
process, each links have strict standards and welding quality
evaluation has different indicators. Therefore, how to make a
rapid detection for weld defect has become a valuable research.
This topic is aimed at weld defect detection of small workpiece.
The study contains the selection of sensor, design of detection
system, hardware platform, software design, user interface
design, etc. In the end, a set of high accuracy detector of weld
defect will be designed.

10023-76, Session Post

Research of non-contact measurement
method for outline dimensions of somespecial workpiece
In industrial production, machine vision is widely used in a variety
of automated testing industry, because of its characteristics of
non-contact, high precision, fast detection time, etc. This paper
introduces a nondestructive detection system for the outline
dimensions of a kind of special workpiece. For the purposeof controlling the quality of image—an ultra-high-resolution
monochrome CCD image sensor is adopted to capture source
image. Then it’s the image preprocessing, including image
cropping processing, grey scale processing, image denoisingprocessing, etc. Then it is the progress of edge extraction, using
gradient operator to get its contour edge. And then piecewise
fitting methods are used to get the dimensions. This method
achieves once measuring multiple outline dimensions without
moving the workpiece. It has been used in industrial production.
The result sees its practical value for meeting the productionneeds, with the advantages of high accuracy, fast speed and highstability of the measurement system through experiments.

10023-77, Session Post

GPU-accelerated phase extraction
algorithm for interferograms: a real-time
application
Xiaoqiang Zhu, Yongqian Wu, Institute of Optics andElectronics (China)

In a rotating Angle measuring system, Errors of grating sensor,
installation and rotor run-outs will affect angle measuring error.
The error caused by rotor run-outs is usually the biggest andthe hardest to eliminate of them. To improve the accuracy, thetable should be fabricated precisely, thus, the table system will
be complicated and expensive. This paper provides a method
to solve the challenge by using two gratings in the same table,
whose gratings respectively grooved on end face and side face.
The error mechanism of end face and side face caused by axial
and radial rotor run-outs by were deduced, which were tested
by a set of experiments. It can be concluded from the results
showed that end face grating is sensitive when radial rotor
run-outs happens, side face grating is sensitive when axial rotor
run-outs happens. Due to the conclusion, combined type gratings
with one end face grating and one side face grating can be used
to restrain the error caused by Rotor Run-outs of table.

Truncated pyramid artifact for
performance evaluation experiments onlaser line scanner
Sen Zhou, Chongqing Academy of Metrology and Quality
Inspection (China) and Chongqing Univ. (China); Jian Xu,
Tao Lei, Chongqing Academy of Metrology and Quality
Inspection (China)
Non-contact measurement techniques using 3D laser scanninghave the power to deliver tremendous benefits to most notably
manufacturing, and have the advantage of high speed and highdetail output. However, procedures for evaluation and verificationof non-contact laser line scanner have not been well-establishedbecause of many influencing factors like scan depth, incident
angle, probe head orientation and surface properties. A truncatedpyramid artifact representation of five- planar with different
included angles was designed and used to straightforwardly
identify the influence of in-plane and out-of-plane angle, as
well as scan depth on dimensional measurement accuracy ofthe laser scanner. Then, a series of easy, fast and representative
experiments, based on this simple artifact, were performed on
a commercial laser line scanner, and found that the output of
this scanner can be improved for metrology applications after
calibration.

10023-27, Session 5

Optical testing, having the merits of non-destruction and highsensitivity, provides a vital guideline for optical manufacturing.
But the testing process is often computationally intensive andexpensive, usually up to a few seconds, which is sufferable
for dynamic testing. In this paper, a GPU-accelerated phaseextraction algorithm is proposed, which is based on the advanced
iterative algorithm. The accelerated algorithm can extract theright phase-distribution from thirteen 1024x1024 fringe patterns
with arbitrary phase shifts in 233 milliseconds on average using
SPIE Photonics Asia

Dabao Lao, Weihu Zhou, Wenying Zhang, Academy of
Opto-Electronics, CAS (China)

10023-79, Session Post

Qiaoling Feng, Chongqing Univ. (China)

122

NVIDIA Quadro 4000 graphic card, which achieved a 12.7x
speedup ratio than the same algorithm executed on CPU and6.6x speedup ratio than that on Matlab using DWANING W5801
workstation. The performance improvement can fulfill thedemand of computational accuracy and real-time application.

·

Development of a high-sensitive opticalprobe for inner profile measurement ofpipes and holes (Invited Paper)
Toru Yoshizawa, Non-Profit Organization 3D Associates(Japan); Toshitaka Wakayama, Saitama Medical Univ.
(Japan)www.spie.org/pa·

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
The requirements of inner profile measurement of pipes andtubes become recently larger and larger, and applications of innerprofile measurement have rapidly expanded to various industrial
fields such as mechanical, automobile and heavy industries. We
have proposed measurement method by incorporating a ring
beam device that produces a circular beam and have developed
various probe cameras for different inner profile measurement.
To meet request for applying to smaller diameter pipes, we tried
to improve the ring beam light source using a conical mirror anda laser diode. At the same time, we are trying to realize highsensitive probe on the basis of selective compliance applied
method (SCAM). Some applications are shown for industrial
purposes.

10023-28, Session 5

Binocular stereo vision system based onphase matching
Huixian Liu, Hebei Univ. of Technology (China); Shujun
Huang, Hebei University of Technology (China); Nan Gao,
Zonghua Zhang, Hebei Univ. of Technology (China)
The binocular stereo vision is an efficient way for three
dimensional (3D) profile measurement and has broad
applications. Binocular stereo vision directly simulates
the physical structure of human eyes,and has choicenesscharacteristics such as small in size, low cost, little power
consumption and high efficiency. Image acquisition, camera
calibration, stereo matching, and 3D reconstruction are four main
steps. Among them, stereo matching is the most important stepthat has a significant impact on the final result. In this paper,a new stereo matching technique is proposed to combine theabsolute fringe order and the unwrapped phase of every pixel.
Different from traditional phase matching method, sinusoidal
fringe in two perpendicular directions are projected. It canbe realized through the following three steps. Firstly, coloredsinusoidal fringe in both horizontal (red fringe) and vertical (bluefringe) are projected on the object to be measured, and capturedby two CCD cameras synchronously. The absolute fringe orderand the unwrapped phase of every pixel along the two directions
are calculated based on the optimum three-fringe numbers
selection method. Then, based on the absolute fringe order of theleft and right phase maps, stereo matching method is presented.
In this process, the same absolute fringe orders in both horizontal
and vertical directions are searched to find the corresponding
points. Based on this technique, as many as possible pairs ofcorresponding points between two cameras are found to improve
the precision of the measurement result. Finally, through 3D
reconstruction of a certain measuring system, this paper analyses
the reconstruction results. The experimental results show that the
proposed method can meet the requirements of high precision
for industrial measurements.

10023-29, Session 5

Algorithms and applications of distortion
correction and American standard-based
digital evaluation in surface defects
evaluating system
Fan Wu, Zhejiang Univ. (China); Pin Cao, Hangzhou
Zernike Optical Technology Co., Ltd. (China); Yongying
Yang, Chen Li, Huiting Chai, Yihui Zhang, Haoliang Xiong,
Wenlin Xu, Kai Yan, Lin Zhou, Dong Liu, Jian Bai, Yibing
Shen, Zhejiang Univ. (China)
The inspection of surface defects is one of significant sectionsof optical surface quality evaluation. Based on microscopic

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scattering dark-field imaging, sub-aperture scanning andstitching, the Surface Defects Evaluating System (SDES) can
acquire full-aperture image of defects on optical elements
surface and then extract geometric size and location informationof defects with image processing such as feature recognization.
However, optical distortion existing in SDES badly affects theinspection precision of surface defects. In this paper, a distortion
correction algorithm based on standard lattice pattern is
proposed. Feature extraction, polynomial fitting and bilinear
interpolation techniques in combination with adjacent subaperture stitching are employed to correct the optical distortionof SDES automatically with high accuracy. Subsequently, in order
to digitally evaluate surface defects with American standard byusing American military standards MIL-PRF-13830B to judge thesurface defects information obtained from SDES, an American
standard-based digital evaluation algorithm is proposed,
which includes judgment algorithm of surface defects size andjudgment algorithm of surface defects concentration. Amongthem, the judgment algorithm of surface defects concentration
establishes weight region for each defect and adopts the methodof overlap of weight region to calculate defects concentration.
This algorithm takes full advantage of convenience of matrix
operations and has merits of low complexity and fast in
running, which makes itself suitable very well for high-efficiency
inspection of surface defects. Finally, various experiments are
conducted and the correctness of these algorithms are verified.
At present, these algorithms have been used in SDES.

10023-30, Session 5

Global optimization to improve system
resolution
Hua Liu, Luoyang Institute of Electro-Optical Equipment(China)To improve the system resolution is an important aspectof the development of a complicated sensor . In order toimprove the resolution of the imaging system, and achieve thetheoretical limit, we introduced the technology principle ofsuper resolution restructure from the point of view on theory
and engineering. Several methods to realize high resolution
restructure configurations are introduced based on theoreticalanalysis and engineering practice. Then, three kinds of restructuretechnologies, that prototype, micro scanning and sub pixel
are described, and how to decrease their shortcomings are
discussed in detail. Furthermore, to improve the band widthby reconstruction without the spectral alias in super resolution
technologies, a new coding technology combining a opticalencoding and the sub pixel is proposed. With the global method,
the bandwidth has been amplified by ten times as compared withthat of traditional ones. Simulation results show that the system
can meet the application requirements in MTF, REA, RMS andother related criteria. Compared with the conventional design,
the system has reduced in volume and weight significantly.
Therefore, the determining factors are the prototype selection
and the system configuration combined optical, electronic andsignal processing technologies, and as an important developing
trend.

10023-31, Session 5

Signal processing in white-light scanninginterferometry by Fourier transformand its application to surface profile
measurements
Songjie Luo, Huaqiao Univ. (China); Osami Sasaki, Huaqiao
Univ. (China) and Niigata Univ. (Japan)#PhotonicsAsia

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
When some dispersion effects are contained in an interference
signal of white-light scanning interferometer (WSI), it is
impossible to measure a reflecting surface position with anaccuracy of a few nanometers. In this situation it becomes
important to process the interference signal both in position andwavenumber domains by using Fourier transform. Although theinterference signal detected with a WSI is a real-valued function,
its complex-valued function is easily obtained by using Fouriertransform. This complex-valued interference signal (CVIS) of
WSI is very effective for the accurate position measurement.
In this paper a general equation of the interference signal of
WSI with a light source of an arbitrary spectrum and Fouriertransform of the interference signal are derived. Based on theseequations, a method for eliminating the dispersion effect in WSI
is proposed. The phase and amplitude distributions of the CVISof WSI without the dispersion effect are utilized to determine
accurately the position of the reflecting surface. A position ofzero phase nearest to the position of maximum amplitude in thetwo distributions is the position of the reflecting surface.

10023-32, Session 5

Calibration of angle-measurement systemfor direction measurements
Yuri V. Filatov, Eugeni D. Bohkman, Pavel A. Ivanov,Roman A. Larichev, Petr A. Pavlov, Saint Petersburg
Electrotechnical Univ. “LETI” (Russian Federation)
Tasks of space orientation very often should be solved by meansof the non-contact optical measurements of angles between
some directions set in space by mirrors. Such measurements
usually are conducted with the use of theodolites or
tacheometers. Usually the accuracy of these devices is limited by
one arc second or a little bit better. In some tasks the accuracy
should be on the level of one tenth of arc second. The way ofsolving the considered problem is the use of dynamic method of
angle measurements. In this method the high-precision opticalencoder continuously rotates around vertical axes together withthe optical null-indicator (NI). The NI generates pulses at thosemoments of time when the optical beam falls normally on the
mirrors. The intervals between these pulses defines the angles
between mirrors. To measure these angles one has to countthe number of the optical encoder output pulses falling in theintervals. The reference direction in the system is formed by thenormal to the reference mirror, which is fixed on the rotating
platform.
The suggested method together with the resolution and accuracyof the optical encoder on the level of 0,1 arc-sec makes it
possible to provide the required quality of considered kind of
measurements.
Important part of the problem is the calibration of themeasurement system. The report describes the various
procedures of calibration and results of experimental research ofsystem calibration.

10023-33, Session 6

Full-field 3D shape measurement ofspecular surfaces by direct phase to depth
relationship (Invited Paper)
Zonghua Zhang, Yue Liu, Shujun Huang, Zhenqi Niu, Jiao
Guo, Nan Gao, Hebei Univ. of Technology (China)
With the development of Three-Dimensional (3D) optical shapemeasurement technique, it has been widely applied in the fieldsof reverse engineering, biological recognition and digitalization ofcultural relics, etc, because of the advantages of high speed, noncontact, and high measurement precision. However, most of the124

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existing techniques are applied to measure objects with diffusedsurface. There are a large number of transparent, black, andreflective objects in industrial applications. The research of shapemeasurement for these objects is still in the early stage. The main
methods in industry are using coordinate measuring machine orchanging the surface characteristics by spraying paint. Therefore,
it is vital to study a direct optical shape measurement method for
specular objects.
Phase Measuring Deflectometry (PMD) has been developed totest specular free-form surfaces,. This kind of technique needs
to display straight sinusoidal fringe patterns on a screen or to
project the structured pattern onto a ground glass. From anotherviewpoint, the reflected fringe patterns via the tested surface
appear deformed with regard to the slope variation of thesurface and the modulated fringe patterns are recorded by animaging (CCD) camera. Phase information in the deformed fringe
patterns are demodulated to obtain the slope of the measured
specular surface and then 3D shape of the tested surface canbe reconstructed by integrating the gradients. All the existing
PMD methods just measure the local slope of smooth surfaces,
instead of the actual 3D shape, and then a two-dimensional (2D)
integration procedure is necessary to reconstruct the shapefrom the measured derivatives, which is incapable of measuringmultiple discontinuous surfaces.
This paper presents a new PMD method to measure specularsurface. A mathematical model is established to directly relate
phase and depth, instead of phase and gradient. Based on themodel, a hardware measuring system has been set up, which
consists of a beam splitter to change the optical path, and two
LCD screens to display the same sinusoidal fringe patterns.
By using model-based and machine vision method, system 3D
calibration is accomplished to provide the required parametersand conditions. The verification tests are given to evaluate theaccuracy of the developed system and to analyze the error
source. The 3D shape of a specular step and a reflective mirror
has been measured. Experimental results show that the proposed
measurement method can obtain 3D shape of specular objects
with discontinuous surface effectively and accurately.

10023-34, Session 6

Three-dimensional surface inspection for
semiconductor components with fringe
projection profilometry
Fuqin Deng, Harbin Institute of Technology (China);
Yi Ding, Wuhan Univ. (China); Jiangtao Xi, Univ. of
Wollongong (Australia); Yongkai Yin, Shandong Univ.
(China)With the increasing integration level of components in modern
electronic devices, three-dimensional automated opticalinspection has been widely used in the manufacturing processof electronic and communication industries to improve theproduct quality. Three dimensional inspection provides complete
information for high-precision metrology and solution for quality
control and automatic assembly. In this paper, we develop
a three dimensional inspection and metrology system forsemiconductor components with fringe projection profilometry,
which is composed of industry camera, telecentric lens andprojection module. This system is used to measure the height,
flatness, volume, shape, coplanarity and quality checking. The
system calibration includes the camera calibration and projector
calibration, the details are explained in the paper. To detect thediscontinuous parts and sharp changes in the internal surface ofsemiconductor components, we employ the fringes with multiple
spatial frequencies to avoid the measurement ambiguity. To
increase the efficiency of using multiple spatial frequencies, thefringes on two different spatial frequencies are selected based on
the number theories which are developed in our previous papers.
The complete three dimensional information of semiconductor

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
component is obtained by fusing the measurement results fromdifferent views. The inspection specifications such as flatness,height, cross-sectional profile, volume and shape are obtained
to evaluate the quality of semiconductor component, the depth
resolution of our system reaches 5 micrometers. This system
can be further embedded for the online inspection of various
electronic and communication products.

10023-35, Session 6

Measurement uncertainty evaluation of thesix-degree of freedom surface encoder
Xinghui Li, Huanhuan Wang, Ni Kai, Graduate Schoolat Shenzhen, Tsinghua Univ. (China); Xiaohao Wang,
Graduate School at Shenzhen, Tsinghua Univ. (China) andResearch Institute of Tsinghua Univ. in Shenzhen (China);
Qian Zhou, Xiang Xiao, Graduate School at Shenzhen,
Tsinghua Univ. (China)
A six-DOF surface encoder can be used to measure the six
degree of freedom (DOF) displacement of the grating. Indeed,
any measurement result is in general just a point estimate ofmeasured quantity, the “true” value of which remains unknown.
For this reason, one should appraise the dispersion of thevalues about the estimate that could as well be attributed
to the measurand. In metrology, this parameter is called
the measurement uncertainty. In this paper, a measurement
uncertainty of the developed six-DOF surface encoder was
systematically investigated to confirm its feasibility on the
precision positioning of planar motion stage. An expanded
uncertainty of 124.4 nm has been calculated in the measurement
results of testing three-axis translational motions over a range of
2.5 um. Among those error sources, cross-talk errors caused by
misalignment existing in experimental setup were identified tobe the largest error source. A method that is able to identify themisalignment factors was proposed for reduction of the crosstalk errors and correspondingly for improvement of measurement
accuracy. An expanded uncertainty of 3.8 arcseconds has been
calculated in the measurement results of testing three-axis
angular error motions at a motion range of ±30 arcsecond.
Periodic cross-talk error components have been observed in the
angular outputs, which were caused by the polarization leakage
in the optical paths of the diffraction beams. The cross-talk errorsof the surface encoder outputs were identified to be the largest
uncertainty source for the surface encoder. Optimization of the
optical design of the surface encoder has then been proposed toeliminate the cross-talk errors.

10023-36, Session 6

Optimum camera setting on fringe edge
detection
Rima Zuriah Amdani, Eka Pratiwi, Ardi Rahman, Purwo
Wibowo, Ctr. for Metrology LIPI (Indonesia)
Optical has widely used in industry and metrology areas.
Research Center for Metrology (RCM) LIPI as a National
Metrology Institute in Indonesia has important role in traceabilityof the national standard. The application of dissemination
provided with calibration service to industry. Percentages of the
optical calibration order in Length Laboratory RCM LIPI for three
years are over than 10% of the total amount order. The large
requirement of calibration service needs a reliable calibration
system. Otherwise, the calibration system in Length laboratory
has large human error factor. Measurement system of the opticalare using contact method between optical test and standard
with monochromatic lamp. Improvement to the system carriedout with a calibration system using image processing. Fringe

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image that observed using eyes are replaced with camera that
automatically controlled in computer. This research is concerned
to find the optimum setting on camera to get a good result on
detecting fringe edge images. Measurements are set on the fix
distance with variation of focus on the camera. The variation
also set using parameter ISO, aperture and shutter time on thecamera. Detection of fringe image are programmed using octave.
fringe edge images result are analyzed visually. It is obtained thaton focus 0.7 m, ISO 100, aperture f/2.5 and shutter time 5s give a
better result on detecting fringe edge images.

10023-37, Session 6

Monitoring the VOCs in chemical plants
with SOF-FTIR
Xin Han, Anhui Institute of Optics and Fine Mechanics(China)Chemical plant area emit large quantities of VOCs, carbon oxides
and other serious impact on the atmospheric environment andhuman health, in recent years, widespread attention. In thispaper, recent development of SOF-FTIR technique of a chemicalplant in Tangshan area for a period of five days of monitoringmeasurement experiment in the monitoring process, select a
closed path monitoring, audience 6.5KM, analyzed between
selected xylene ( C8H10_1), p-xylene (C8H10_3), p-cresol(C7H8O) as the target component, and nonlinear least squares
inversion gas concentrations and fluxes. Experimental results
show that, SOF-FTIR technology has broad application prospects
in terms of chemical emissions monitoring area, the developmentof relevant policy guidelines for government departments
providing effective help.

10023-38, Session 6

An accurate approach for calibratingrotational angle of camera
Zhenqi Niu, Kuo Liu, Zonghua Zhang, Hebei Univ. ofTechnology (China)
With the advent of the information technology, the color digital
camera and the depth camera are more and more widely used toobtain color and 3D scene information in various fields. However,such cameras can only obtain data in one direction. In order toobtain the scene information of a larger or 360 degree field ofview, the camera needs to move or rotate to collect a series of
2D or 3D data . Especially in a room, the data of the large field ofview can be obtained by the camera rotated around a rotation
axis. In order to obtain the scene information of a larger or 360
degree field of view, it is necessary to accurately know the angleof the camera rotating around a fixed axis that directly affects
the quality of the registration result .
This paper presents a novel method to calibrate the rotated angleof a camera around a fixed axis by using a large scene camera
and two high precise checkerboards. The large scene camera
is fixed and has the same imaging direction as the calibrated
camera. One checkerboard is placed in front of the two cameras
to determine their relative positions. The other checkerboard isrotated to several positions along the camera. At each position,
the big scene camera captures the checkerboard to calibrate theangle of the rotation axis. Experimental results show that the
proposed calibration method can accurately obtain the rotational
angle of a camera around a fixed axis.

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV

10023-39, Session 7

Guohang Hu, Huijie Huang, Shanghai Institute of Optics
and Fine Mechanics (China)

Temporal phase unwrapping algorithms
for fringe projection profilometry: acomparative assessment based on astochastic noise model (Invited Paper)With non-contact, non-destructive and high precision
measurement, the ellipsometer is widely used to detect the
thickness, refractive index and extinction coefficient of the thinfilm. The traditional ellipsometer can only adapt to single-point
measurement. To overcome this disadvantage, the imaging
ellipsometer with microscopy has been developed. The current
commercial imaging ellipsometer can realize 10?m lateral
resolution and 2mm?2mm field of views.

Chao Zuo, Nanjing Univ. of Science and Technology(China)In fringe projection profilometry (FPP), temporal phaseunwrapping is an essential procedure to recover an unambiguous
absolute phase even in the presence of large discontinuities
or spatially isolated surfaces. So far, there are typically threegroups of temporal phase unwrapping algorithms proposed in
the literature: multi-frequency (hierarchical) approach, multiwavelength (heterodyne) approach, and number-theoretical
approach. In this talk, the three methods are compared indetails by analytical, numerical, and experimental means. The
basic principles and recent developments of the three kind ofalgorithms are briefly recalled. Then, the reliability of different
phase unwrapping algorithms is compared based on a rigorous
stochastic noise model developed. Furthermore, this noisemodel is used to predict the optimum fringe period for each
unwrapping approach, which is a key factor governing the phasemeasurement accuracy in FPP. Simulations and experimental
results verified the correctness and validity of the proposed noisemodel as well as the prediction scheme. We will show that themulti-frequency temporal phase unwrapping provides the best
unwrapping reliability, while the multi-wavelength approach is themost susceptible to noise-induced unwrapping errors.

10023-40, Session 7

Li Dong, Haoming Guo, Guiwen Lin, Yong Tian, Jindong
Tian, Shenzhen Univ. (China)
Structured light 3D shape measurement has been wildly used inindustrial component detection, reverse engineering, 3D molding,robot navigation, medical and many other fields. In this paper,
a novel structured light based on spatio-temporal encoding is
proposed. The new designed patterns consist of grey coding andbinary coding in space, which are projected to the measurement
object in sequence to form a unique gray vector temporally forevery pixel. And a decoding algorithm is presented to convert
the unique gray vector to a code value which could be used ascharacteristic information for binocular matching. Comparedwith the temporal phase shift method, fewer patterns are needed
and the time-consuming phase unwrapping and trigonometricfunctions calculation are avoided in this method. An Embedded
system based on DM3730 is set up for to perform the proposed
method, which is a SOC consist of a DSP core and an ARM
core. We packaged the gray vector modulating method into
xDM complaint algorithm which is appropriate for dual corecommunication. The ARM side application realized the controlof the projector and the camera. The DSP algorithm for dataprocess is then called by the application. 3D object measurement
experimental results show the feasibility of the system.

Imaging ellipsometer with large field-ofview
Liyuan Gu, Aijun Zeng, Qiao Yuan, Weilin Cheng, Shiyu Hu,·

10023-42, Session 7

Hybrid probing technique for coordinate
measurement using an optically-trapped
microsphere

Engineered surfaces have been fabricated to provide enhanced
properties such as low friction, anti-adhesive behavior, or low
reflection of light. At micro-scales, surface force highly affects thefunctionality of mechanical parts. So as to reduce surface force
such as friction, micro mechanical parts that have engineered
surfaces are demanded. In order to investigate the functionalityof the textured micro parts, it is necessary to evaluate both thethree-dimensional shape and the surface topography along with
its geometry. Then we propose hybrid probing technique using
an optically trapped micro sphere. Tightly focused laser beam
makes it possible for a dielectric micro sphere to sustain near the
focal point in the air. The dynamic behaviour of the micro spherechanges as the result of the interaction of the surface. Therefore,
the surface is detected by monitoring the micro sphere. This
enables the three-dimensional shape measurement of thesubstrate. On the other hand, Surface topography is imaged withthe lensing effect of the trapped micro sphere. Therefore, thistrapped sphere is used as both a probe for coordinate metrology
and a micro-lens in optical microscopy in this study. This present
investigation deals with the development and fundamental
validation of the hybrid measurement system with the opticallytrapped micro sphere. The measurement result with highperformance was demonstrated using the diffraction grating.

10023-43, Session 7

Research on application of photoelectricrotary encoder in space optical remotesensor10023-41, Session 7

SPIE Photonics Asia

In the experiments, a thin film with non-uniform thickness ismeasured. The experimental result agrees with the measurement
result of the AFM. The usefulness of the imaging ellipsometer isverified.

Yuki Yamaguchi, Osaka Univ. (Japan); Masaki Michihata,
The Univ. of Tokyo (Japan); Yasuhiro Mizutani, Yasuhiro
Takaya, Osaka Univ. (Japan)

Embedded 3D shape measurement
system based on a novel spatio-temporal
encoding

126

In this paper, we present an imaging ellipsometer which has 13?mlateral resolution and 13mm?13mm field of views. In the imaging
ellipsometer, the polarizer-compensator-sample-analyzer (PCSA)
structure is used. The sample is imaged on a CCD by a telecentric
imaging system. The CCD is tilted to satisfy the Scheimpflug
condition. The rotation accuracy of all polarizing opticalcomponents which are controlled by servo motors is smaller than
0.01?. The accuracy of the incidence and reflection angles canreach 0.001° with the stepping motor and the grating ruler. In its
measurement, the light extinction measurement method can beutilized to eliminate the influence of light intensity fluctuation.

Jun Zheng, Yuanyuan Wang, Haoyang Li, Shao-fan Qi,
Zhan-dong Zhang, Beijing Institute of Space Mechanics

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
and Electricity (China)

10023-45, Session 7

In space optical remote sensor, especially for wide swath
detecting, focusing control system for the focal plane, which is
the real-time control and dynamic measurement system, need to
be designed to ensure the best image quality.

Detection algorithm of circular-coded
point in vision measurement

The measuring instrument called a potentiometer, which is usedas position feedback devices in order to create “closed loop”
control, is the simplest and important method of motion control
used in this system. But both electro-mechanical and digitalpotentiometers generally have some limitations, such as poor
tolerances, poor temperature coefficients and a stop resistance.
To resolve these issues as above, this article presents a newmeasuring method with photoelectric rotary encoder, consistingof the photoelectric conversion system and the signal processsystem. For using in the aerospace areas, three aspects of design
should be considered seriously, including reliability, flexibility andsimplicity, without making it complex.
In this focusing control system, the photoelectric conversion
system is fixed with motor axis, which could real-time transformthe angle information into a certain analog code signal. With thesignal process system, after analog - to - digital converting anddata format processing of the certain analog code signal, thefocusing control system can receive the digital precision angle
code which can reflect the current moving position of focal planeby conversion of angle-to-line.
As mentioned above, because of characters such as highresolution, high accuracy, long service life, and easy to maintain,
this photoelectronic and precision angle measurement device is agood match for the focusing control system.

10023-44, Session 7

Application of grey relational analysis onlens distortion correction
Qiyue Wang, BeiHang Univ. (China); Zili Zhang, Academyof Opto-Electronics, CAS (China); Zhongyu Wang,
BeiHang Univ. (China); Weihu Zhou, Academy of OptoElectronics, CAS (China)
High-precision correction for lens distortion is the coretechnology in vision based measurements. The current linear
regression method (LRM) which is based on statistical theory
needs a mass of collinear points to estimate the lens distortion.
However, since the size of image is constant in a certain camera.
The more points mean greater measuring distance and lower
measurement accuracy. In this paper, according to the principleof straight line projection invariance, a lens distortion correction
method based grey relational analysis (GRA) is proposed. The
proposed method utilizes particular grey relational degree ofimage feature points to estimate the distortion coefficientsof lens. The GRA needs less feature points and owns higher
computational precision compared with the LRM. In order tovalidate the validity of proposed method. Computer simulation
and real experiment are conduct. The simulation results indicatethat the proposed method is manifest well in different number offeatures points. In addition, the proposed method also comparedwith other LSM in a real experiment. The rectified images areused to calibrate the camera. The mean reprojection error using
rectified images corrected by our proposed method is 0.127
pixels, which is one third less than 0.368 pixels by LSM. The
results indicate that the measurement precision using proposed
method is superior than LSM. At the meantime, the calibrated
camera is used to construct vision measurement. The mean
measurement error calculated by LSM is 0.173mm nearly twotimes than 0.095mm by GRA. Therefore, the proposed GRA issuperior to LSM under the given experimental condition.

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Ran Chen, Kai Zhong, Zhongwei Li, Huazhong Univ. of
Science and Technology (China)
Distributing coded points on the measured object is a reliable
and common method for achieving optimum target location andaccurate matching of corresponding points among multi-view
images?However, it is difficult to decode the coded point while
the image noise and the projection angle is large. Aiming at
solve this problem, an accurate and stable detection algorithm
was proposed. Firstly, an accurate ellipse detection which can
get sub-pixel locations was adopted to extract targets, andseveral rules according to the target’s shape and size were used
to remove the non-target points. Then, gray scale gradient in
the circular was calculated to find the point whose gray scale ischanging, and the central angle of coded arc will be calculated
to decode the target. Experiments show that the algorithm canidentify and locate coded points accurately, and it is robust to thechange of projection angle and noise.

10023-46, Session 8

An underwater ranging system by using
photoacoustic effect on solid surface
Kai Ni, Kai Hu, Qian Zhou, Graduate School at Shenzhen,
Tsinghua Univ. (China); Lidai Wang, City Univ. of Hong
Kong (China); Xinghui Li, Xiaohao Wang, Graduate Schoolat Shenzhen, Tsinghua Univ. (China)
In this paper, an underwater ranging system based on
photoacoustic effect on solid surface is proposed. Differingfrom the traditional photoacoustic detection system, in this
proposal, a high power blue-green laser beam raying from alaser source that is located underwater, is directly incident on thetarget surface, where the photoacoustic effect on solid surface
occurs and a sound source region is formed. The acoustic signal
spreads outward from the sound source, later it is received byan ultrasonic receiver. According to the time delay between
transmitting laser and receiving photoacoustic signal, and the
speeds of light and sound under the water, the distance between
the target and the detection system can be calculated. Since
efficiency of the photoacoustic conversion on solid surface
is higher than that of sea water under the same conditions,this system can ensure a large measurement range and at thesame time a high spatial resolution. Based on this principle andpreliminary calculation, a resolution of mm when a target is
located at a distance of up to 200 m can be effectively achieved.
Experimental system is constructed to verify the feasibility of thistechnology.

10023-47, Session 8

Rail profile control using laser
triangulation scanners
Yuri V. Filatov, ?lexandr M. Boronahin, Daniil Y. Larionov,Liudmila N. Podgornaya, Roman V. Shalymov, Eugeni D.
Bokhman, Saint Petersburg Electrotechnical Univ. “LETI”(Russian Federation)
Railway state monitoring is needed to ensure the railtransportation safety. A wide range of parameters is a subject ofmonitoring: rail condition characteristics (defects inside rail andon the running surface) and the geometric parameters of track.
The first ones are traditionally controlled using flaw detecting and#PhotonicsAsia

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV
magnetometric systems. The latter are measured by determining
the displacement of each rail section. It is traditionally carriedout by the contact method that has obvious disadvantages.
Therefore, non-contact (optical) methods are used in modern
track condition monitoring systems.
Measurement of track gauge, cross level, longitudinal level andalignment requires knowledge of rails head location in eachsection. Displacement in transverse plane of rail head point
located at a distance of 14 mm below the running surface must
be controlled. It is carried out by detecting of each rail profile
using triangulation laser scanners.
Optical image recognition is carried out successfully in thelaboratory, approaches used for this purpose are widely known.
However, laser scanners operation has several features on
railways leading to necessity of traditional approaches adaptation
for solving these particular problems. The most significant
problem is images noisiness due to the solar flashes and theeffect of “Moon path” on the smooth rail surface. Using of opticalfilters gives inadequate result, because scanner laser diodes
radiation frequency varies with temperature changes that forbid
the use of narrow-band filters. Consideration of these features
requires additional constructive and algorithmic solutions,
including involvement of information from other sensors of thesystem. The specific usage of optical scanners for rail profiles
control is the subject of the paper.

10023-48, Session 8

Non-uniform sampling knife-edge method
for camera modulation transfer function
measurement
Yaxuan Duan, Xi’an Institute of Optics and Precision
Mechanics, CAS (China); Xun Xue, Institute (China)
Traditional slanted knife-edge method experiences large errors
in the camera modulation transfer function (MTF) due to tilt
angle error in the knife-edge resulting in non-uniform samplingof the edge spread function. In order to resolve this problem,a non –uniform sampling knife-edge method for camera MTF
measurement is proposed. By applying a simple direct calculationof the Fourier transform of the derivative for the non-uniform
sampling data, the camera super-sampled MTF results are
obtained. Theoretical simulations for images with and without
noise under different tilt angle errors are run using the proposed
method. It is demonstrated that the MTF results are insensitive
to tilt angle errors. To verify the accuracy of the proposed
method, an experimental setup for camera MTF measurement
is established. Measurement results show that the proposed
method is superior to traditional methods, and improves theuniversality of the slanted knife-edge method for camera MTF
measurement.

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10023-49, Session 8

A precise reference position detection
method for linear encoders by using a
coherence function algorithm
Kai Ni, Xinghui Li, Xiang Xiao, Qian Zhou, Huanhuan Wang,
Graduate School at Shenzhen, Tsinghua Univ. (China);
Xiaohao Wang, Graduate School at Shenzhen, Tsinghua
Univ. (China) and Research Institute of Tsinghua Univ. in
Shenzhen (China)
This paper proposed a new method for reference position
detection with high precision for linear encoders by using a homedesigned scale grating and a coherence function algorithm.
Differing from the traditional methods, in which the reference
position alignment and calibration of reference position wasachieved by detecting the peak of the signal with a negative
pulse at the reference position, the method in this paper nolonger detects the single peak of the signal, but matching andaligning the integral shape of reference position signal throughthe algorithm based on the coherence function. The proposed
method does not require a complex design and precision
manufacturing of reference position. Due to the coherencefunction algorithm, a multi-pulse reference position signals
design is available, which not only reduces the difficulty ofreference position design and manufacturing, but also shortens
the length of reference position area so that the negative effecton the grating diffraction efficiency is limited. What is more,robustness of the reference detection method introduced here isgreatly enhanced. Experimental results show that the accuracyof reference detection can still achieve 2 times of resolution evenunder the low signal to noise ratio (SNR) of 2dB.

10023-50, Session 8

Development of an edge sensor based on
polyview optics and laser triangulation
principle
Yinan Li, Hagen Bossmeyer, Markus Kästner, Eduard
Reithmeier, Leibniz Univ. Hannover (Germany)
Laser line triangulation sensors as non-contact measurement
devices are very desirable in many inspection and measurement
situations. Compared to common sensors like capacitive,
inductive or ultrasonic devices, laser line triangulation sensors
are available with longer working distances, higher resolutions
and accuracy specifications. In different applications and diverse
industry sectors, the sensors are available with a wide variety ofconfigurations and specifications which replace and outperform
older types of contact measurement sensors. However, thecommon laser line triangulation sensors have a geometrical
optics limit for the measurement range and direction. The
measurement range of a single sensor is limited by the rotation
angle between the imaging detector and the projected structured
laser light. The measurement direction is limited by the 180° fieldof view (FOV) of the imaging lens and the 2D detector, whichhave flat light sensitive elements like CCDs or CMOS. For thisreason, to scan samples with great curved surfaces like edges, asingle laser line triangulation sensor is not capable of measuring
the entire form of the object. In this case, an entire 3D edgemeasurement requires either multiple measurements of one
single sensor from different directions or a multi sensor system.
The purpose of this paper is to explain the development of anedge sensor based on in-house designed polyview optics andthe well-known laser triangulation principle. The configuration,
the calibration process and the measurement results of this edge
sensor will be discussed.

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Conference 10023: Optical Metrology and Inspection
for Industrial Applications IV

10023-51, Session 8

Arbitrary optical frequency synthesis
traced to an optical frequency comb
Zihang Cai, Honglei Yang, Yan Li, Haoyun Wei, Tsinghua
Univ. (China)
An arbitrary optical frequency synthesizer with a broad tuning
range and high frequency accuracy is presented. The system
includes an external cavity diode laser (ECDL) as the output laser,an Erbium-doped optical frequency comb being a frequency
reference, and a control module. The optical frequency fromthe synthesizer can be continuously tuned by the large-scaletrans-tooth switch and the fine intra-tooth adjustment. Robust
feedback control by regulating the current and PZT voltage
enables the ECDL to phase-lock to the Erbium-doped opticalfrequency comb, therefore to keep stable frequency output.
In the meanwhile, the absolute frequency of the synthesizer isdetermined by the repetition rate, the offset frequency and thebeat frequency. All the phase lock loops in the system are traced
back to a Rubidium clock. A powerful and friendly software isdeveloped to make the operation convenient by integrating
the functions of frequency setting, tuning, tracing, locking andmeasuring into a LabVIEW interface. The output frequency
tuning span and the uncertainty of the system are evaluated as>4 THz and <3 kHz, respectively. The arbitrary optical frequency
synthesizer will be a versatile tool in diverse applications, such assynthetic wavelength based absolute distance measurement andfrequency-stabilized Cavity Ring-Down Spectroscopy.

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129

Conference 10024:
Optics in Health Care and Biomedical Optics VII
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10024 Optics in Health Care and Biomedical Optics VII

10024-1, Session 1

the flow contrast. Both flow phantom and in vivo animal studies
on cerebral vascular imaging demonstrated that the proposed
angular compounded Angio-OCT can offer a ~50% decreaseof misclassification errors and an improved flow contrast andvessel connectivity. This method is beneficial to facilitating theinterpretation of OCT angiograms in clinical applications.

Self-assembled photonic crystals forbioassay (Invited Paper)
Zhongze Gu, Southeast Univ. (China)
Photonic crystal (PC) is composed of two and more mediums
with periodic nanostructure. The unique optical property andcharacteristic nanostructure of the PC provide effective means
for biological and chemical analyses. In our group, we developed
a series of analytical methods by using self-assembled PC.
1) Label-free detection of biomolecule. By utilizing the volume
and refractive index change of biomolecules in PC,we realizedlabel-free detection and visual detection of biomolecules.
2) Analysis of gas. Mesoporous PC with high specific surface aredeveloped. By using this kind of material, we realized the analysis
of gas molecules with PC.
3) Multiplex detection. One of the key techniques of multiple
biological analysis is to identify different biological events
simultaneously. Biomolecule encoding is the core technique forthem ultiplex detection. By taking advantage of the spectrumencoding ability of the PC, we fabricated the encoding carriers
for biomolecules with low fluorescence background and highstability.
4) PC paper-based chips. We realized the separation of
biomolecules by taking advantage of the periodic nanostructureof PC. Meanwhile, the fluorescent signal for detection wasenhanced due to the stop-band of the PC.
5) Organ chip analysis. We fabricated 3D cells caffolds on
microfluidic chips to simulatethe in vivo environment forcell growth.On-line analysis was also realized with the PC
microcarriers.

10024-2, Session 1

Angular compounded optical coherence
tomography angiography for flow contrast
enhancement
Pei Li, Liping Zhou, Zhejiang Univ. (China); Yuxuan Cheng,
Zhejiang Univ (China); Zhihua Ding, Peng Li, Zhejiang
Univ. (China)
Optical coherence tomography angiography (Angio-OCT) isa promising imaging modality that is capable of providing alabel-free, high-resolution and high-contrast image of biologicaltissue microvasculature. Typically, the blood flow contrast is
implemented by mathematically analyzing the temporal dynamics
of light scattering, and setting a threshold to distinguish the
dynamic blood flow from the static tissue bed. However, highflow contrast is degraded by the residual overlap that results inmisclassification errors between dynamic and static signals instatistical analysis. We have demonstrated that flow contrast canbe enhanced using a novel angular compounded Angio-OCT tofacilitate the interpretation of angiograms. Because a continuous
modulation is induced by the offset that the probing light isaway from the beam center in the typical OCT sample arm,different incidence angles in the probing beam can be encodedin B-scan modulation frequencies. The complex-valued spectralinterferogram is reconstructed by removing the conjugate terms
in the depth space and its Fourier transform along the transversal
fast-scan direction generates a wide conjugate-free B-scanmodulation spectrum in the full space of the spatial domain. By
splitting the modulation spectrum, angle-resolved independent
sub-angiograms are generated and then compounded to enhance

130

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10024-3, Session 1

Optical Image-guided cancer surgery
Xiao Feng Yang, First Hospital of Shanxi Medical Univ.
(China)Design visible and near-infrared LED ring light, multi-channel
band-pass filter, multi-spectral 2 CCD cameras, image fusion
software, we have developed the surgical navigation system withbeam split and fusion the visible and near-infrared fluorescenceby technology integration research, and established the
production process and testing system.
Image-guided cancer surgery has the potential to be a powerfultool in guiding future surgical care. Photoimmunotherapy is atheranostic concept (simultaneous diagnosis and treatment) on
the verge of clinical translation, and is highlighted as an effective
combination of image-guided surgery and intraoperative
treatment of residual disease. Multispectral optoacoustic
tomography, a technique complementary to optical imageguided surgery, is currently being tested in humans and isanticipated to have great potential for perioperative andpostoperative application in surgery.
Phage display and the human non-muscle-invasive bladdercancer cell line BIU-87 were used to identify a peptide. The
isolated phage display peptide (CSSPIGRHC, named NYZL1)
was tested in vitro for its binding specificity and affinity.
Accumulation into xenograft tumors in a nude mouse model was
analyzed with FITC-labeled NYZL1. NYZL1, with strong tumor
homing ability, was identified by in vivophage library selectionin the bladder cancer model. The NYZL1 phage and synthetic
FITC-labeled NYZL1 peptides bound to tumor tissues and cells,
but were hardly detected in normal control organs. Notably,
accumulation of FITC-NYZL1 in bladder tumor cells was timedependent. Biodistribution studies of xenografts of BIU-87 cells
showed accumulation of injected FITC-NYZL1 in the tumors, andthe bound peptide could not be removed by perfusion after 24 h.

10024-4, Session 1

The development of intravascular
photoacoustic/ultrasonic/OCT tri-modality
imaging technology for vulnerable plaqueidentification
Xiaojing Gong, Ji Leng, Riqiang Lin, Liang Song, Shenzhen
Institute of Advanced Technology (China)
The rupture of vulnerable plaques is the major cause of acuteheart attacks and strokes. The accurate diagnosis of vulnerable
plaque is of vital important for the treatment, which depends
on the identification of some key morphological and functionalfeatures, including thin fibrous caps, large lipid-rich cores,
increased inflammation, and vasa vasorum. Current clinicalintravascular imaging modalities, such as intravascular ultrasound(IVUS) and intravascular optical coherence tomography (IVOCT),
are mainly capable of detecting plaque morphological features
such as the overall plaque burden and thin fibrous caps. However,the detecting of lipid pool and inflammation remains challenging

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
for them. Intravascular photoacoustic (IVPA) imaging is capableof imaging the plaque composition and inflammation, benefitingfrom its high sensitivity to optical absorption. Consequently,
the integration of IVPA, IVUS and IVOCT will provide the abilityof acquiring both morphological and physiological information
simultaneously.
In this study, for the first time to our knowledge, a tri-modality
intravascular imaging system is developed, which is capableof photoacoustic, ultrasonic, and OCT imaging with a single
catheter of ~0.9 mm in diameter. As a feasibility study, we
validated the system by photoacoustic spectroscopic imaging
of peri-adventitial adipose tissue excised from a porcine heart
and tri-modality imaging of a stent deployed within a healthy
rabbit aorta segment. These improvements potentially enable
the acquisition of comprehensive macroscopic and microscopic
structural information as well as the functional information,such as plaque composition and inflammation, leading to moreaccurate identification of vulnerable plaques.

10024-5, Session 1

Malignant melanoma and basal cell
carcinoma control with Raman andautofluorescence spectroscopy
Ivan A. Bratchenko, Dmitry N. Artemyev, Yulia A.
Khristoforova, Oleg O. Myakinin, Samara State Aerospace
Univ. (Russian Federation); Alexanrer A. Moryatov,
Sergey V. Kozlov, Samara State Medical Univ. (RussianFederation); Valery P. Zakharov, Samara State Aerospace
Univ. (Russian Federation)
Problem of increased incidence of cancer is known worldwide.
For instance yearly in Russia more than half a million cases ofcancers are registered and the largest amounts of deaths arecaused by melanomas. In this regard optical methods may bevery useful for tissues analysis. They allow one to find chemicalcomposition of tested tissues in vivo and in real time mode.
In this study we present a method of skin neoplasms analysis
based on Raman and autofluorescence effects. Raman signal was
stimulated by 785 nm laser and autofluorescence was stimulated
in visible and NIR regions by two lasers 457nm and 785 nm.
Experiments were approved by the ethical committee of Samara
State Medical University. More than 100 tissue samples were
tested. Raman and autofluorescence spectrums were registeredfor neoplasms and surrounding normal tissues to design an
optical method of malignant tissues detection. For melanomas
and basal cell carcinomas detection proposed method
demonstrated accuracy of 91% and 89% for Raman spectra
and autofluorescence analysis correspondently. Combinationof Raman and autofluorescence spectra analysis leads to theincrease of precise malignancy detection up to 96%.
Proposed method of skin neoplasms optical analysis demonstratehigh potential for malignant melanomas detection Analysis of
autofluorescence spectra is simple and may be used in mass
screening applications, as fluorescecne registration is possible
within a few seconds. Raman spectra registration helps toincrease accuracy of oncological pathologies diagnosis, but
requires more time for spectra collection.

10024-6, Session 1

Quantitative detection of tissue
fluorescence

Normal Univ. (China) and Univ. of Colorado Denver(United States)
Fluorescence is the emission of light from a fluorescence
substance that absorbs light or other electromagnetic radiation,in which the wavelength of emission is the same or different fromthe excitation radiation in the de-excitation. Tissue fluorescenceis divided into intrinsic and extrinsic origins. The method ofsignal collection and data processing of tissue fluorescencemight be divided into two categories: fluorescence imaging
and fluorescence spectroscopy. The quantitative detection oftissue fluorescence is still challenging. In this study, we designed,
built and validated an in vivo tissue fluorescence detection
system based on the absorption and emission spectra of thetarget fluorescent substance. In ex vivo experiment, we utilized
a tissue model by controlling the absorption and scattering
coefficients. We optimized excitation and examined theirradiance with standard light source. In in vivo experiment, byprocessing the acquired fluorescence emission spectra of thefluorescent substance, tissue optical properties (e.g. ?a and ?s),and the calibrated absorption of excitation and emission light,
we could quantitatively calculate the fluorescence intensity.
Further by extracting the fluorescent substance from tissue weverified the accuracy and reliability of fluorescence detection
system. Experimental results show that this approach mightprovide a noninvasive real-time and sensitive method for tissue
fluorescence quantitative detection.

10024-7, Session 2

Nanoprobes for optical bioimaging andlight-enacted therapy (Invited Paper)
Tymish Y. Ohulchanskyy, Shenzhen Univ. (China) andUniv. at Buffalo (United States); Junle Qu, Shenzhen Univ.
(China)
The ability of light to penetrate a tissue is a key to diagnostic(e.g., optical bioimaging) and therapeutic (e.g., light induced
therapy) applications of biophotonics, which is among the mostpromising and actively developing multidisciplinary approaches
that are expected to make a major impact on health care. This
presentation will provide results of our work on multifunctional
nanostructures comprising inorganic and organic materials
to tailor the nanoformulations for optical bioimaging andlight induced therapy. The photoactive nanoplatforms, which
will be presented, include organic polymer and silica-based
nanoparticles, rare-ion doped nanophosphors, magnetic andplasmonic nanoparticles, as well as their hybrids. While providing
optical contrast, the developed nanoplatforms can be also
garnished with other imaging modalities, enabling the integrationof cellular, tissue and whole body imaging and allowing us toemploy a single formulation within multiple imaging techniques.
Coupled with a therapeutic payload and conjugated withspecific targeting agents, these imaging nanoplatforms turn into
theranostics agents which act in the treatment of a disease andprovide for real-time monitoring of the treatment efficacy. As aresult, theranostics nanoparticles, which combine therapeutics
and medical imaging modalities, allow for the “see and treat”
and “see-treat-and see” approaches. The talk will demonstrateexamples of applications of nanoparticles as optically traceable
agents for detection and treatment of cancer and conclude witha discussion on the challenges and opportunities in the field of
optical bioimaging and light induced therapy using photoactive
nanoformulations.

Jian Zou, Wei Gong, Weijun W. J. Li, Fujian Normal Univ.
(China); Qing Ye, Provincial Clinical Medical College
of Fuzhou Medical Univ. (China); Zheng Huang, Fujian

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Conference 10024:
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10024-8, Session 2

reactive sites, hydrogel network structure expands, increasing the
spacing of periodic structure of the colloidal crystal and leading
to the red-shift of the diffraction wavelength, which can bemonitored by fiber optic spectrometer.

A novel handheld linear-array
photoacoustic probe towards clinicaltranslation for sentinel lymph node
mapping

10024-11, Session 2

Chengbo Liu, Mucong Li, Liang Song, Shenzhen Instituteof Advanced Technology (China)

Detection and classification of ebola on
microfluidic chips

Breast cancer is the leading cause of death to women aroundthe world. Sentinel lymph node (SLN) biopsy is currently thestandard of care for staging of this disease. To conduct SLN
biopsy, radioactive tracers and dyes are injected followed by anopen surgery to identify SLN, causing major complication risks.
Photoacoustic (PA) imaging is gaining widespread attention
due to excellent imaging contrast and high resolution for deep
imaging, which has also been demonstrated to be able to identify
SLN after localized administration of PA contrast agents, andtherefore potentially eliminate the usage of radioactive tracers
and invasive open surgery. To perform SLN imaging in clinics,
several research groups tried integrating PA imaging into clinicalultrasound imaging system by applying laser excitation from theside of the handheld linear array ultrasound probe. Simple as it is,
this design suffers from low laser energy utilization efficiency andinconvenient handling of the probe due to the oversize issue.

Xue Lin, Tsinghua Univ. (China); Qin Huang, Yue Kou,
National Engineering Research Ctr. for Beijing Biochip
Technology (China)

In this study, we developed a compact handheld linear array
PA imaging probe based on a novel optical-acoustic co-axial
design. Compared with previously reported probes, our probe
is more clinically friendly and the excitation laser energy is more
efficiently utilized, enabling higher signal-to-noise ratio (SNR) as
well as deeper imaging capability. The performance of the probe
was validated by imaging a rat SLN embedded 2 centimeters
below tissue surface in vivo.
The improved SNR together with reduced probe size suggests
the handheld probe is of great potential to be further translated
for clinical applications.

Boronate affinity structural coloredcontact lens for tear glucose monitor
Panmiao Liu, Zhuoying Xie, Zhongze Gu, Southeast Univ.
(China)Rapid increasing of diabetes mellitus is now global problem
and development of a safe and convenient blood sugar levelmonitoring technology is strongly required. While “finger
pricking” is a relatively painless and commonly used method forblood glucose monitoring today, there are several points to be
improved.
Colloidal crystals, three-dimensional periodic microstructural
materials, have successfully been applied in some chemical andbiological moleculars sensing. In particular, the colloidal crystalhydrogels with three dimensional network structures exhibt
reversible physical dimension changes, such as expansion andcontraction, with the variation of external environment. Thechange will alter the spacing of periodic structure of colloidal
crystal, leading to the variation of diffraction wavelength.
In this research, we present a novel strategy for the glucose
monitor by boronate affinity structural colored contact lens.
Structural colored contact lenses are fabricated by a typicalcommercial contact lenses hydrogel colored by colloidal crystals
paints. Colloidal crystals paints are the close-packed inverse
opal void nanostructure, and also the non-close-packed colloid
particles ordered nanostructure. With the boronate a?nity as thefunctional elements for pre-hydrogel of contact lens, contact lenshydrogel reversibly appeals alternatives to glucose molecules.
As a resualt, when the glucose molecules combine with boronate

SPIE Photonics Asia

10024-12, Session 2

A noninvasive optical technique forstenosis surveillance of a hemodialysis
vascular graft
Boonsong Sutapun, Lawan Sampanporn, Suranaree Univ.
of Technology (Thailand); Armote Somboonkaew, National
Electronics and Computer Technology Ctr. (Thailand)

10024-9, Session 2

132

Point-of-care testing (POCT) for an infectious diseases isthe prerequisite to control of the disease and limitation of its
spread. A microfluidic chip for detection and classificationof four strains of Ebola virus was developed and evaluated.
This assay was based on reverse transcription loop-mediatedisothermal amplification (RT-LAMP) and specific primers for
Ebola Zaire virus, Ebola Sudan virus, Ebola Tai Forest virus
and Ebola Bundibugyo virus were designed. The sensitivityof the microfluidic chip was under 1000 copies per milliliter,as determined by ten repeated tests. This assay is uniquein its ability to enable diagnosis of the Ebola infections andsimultaneous typing of Ebola virus on a single chip. It offers fast
reaction time, ease of use and high specificity. These features
should enable POCT in remote area during outbreaks of Ebola
virus.

·

Prosthetic grafts have been used as a bypass conduit for ahemodialysis in renal failure. The grafts may develop stenosis
and leading to subsequent thrombosis. Frequent monitoringand surveillance of vascular access are important to the careof hemodialysis patients. Early stenosis identification could
enable intervention prior to thrombosis. For surveillance of thegrafts, blood flow and pressure are measured with color-flow
duplex ultrasound and dynamic venous pressure techniques.
These techniques take considerable amount of time and costand require expensive equipment. In this work, we report thefeasibility study of using a near-infrared (NIR) imaging fornoninvasive stenosis surveillance. Optical properties of humanskin and tissues allow NIR light to penetrate deep enough tovisualize the blood vessels. Vascular grafts are made from plastic
that has a large different optical absorption in the NIR from thatof the surrounding tissues. As a result, the graft luminal diameterand shape detection should be possible using the NIR imaging.
In this study, we have developed a phantom with an embedded
polytetrafluoroethylene (PTFE) tubing mimicking human tissue
and a hemodialysis graft, respectively, to evaluate the possibilityof the proposed technique. We found that NIR image can be used
to visualize and differentiate the PTFE tubes with a diameterof 4-8 mm at the depth up to 6 mm. Future work on an invivo vascular graft imaging experiment to explore the clinicalpossibility of the NIR imaging technique will be discussed.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-13, Session 3

Cell counting for in vivo flow cytometry
with unstable background signals (Invited
Paper)
Xunbin Wei, Shanghai Jiao Tong Univ. (China)
The in vivo flow cytometry (IVFC) is a useful technology todetect circulating cells dynamically in living animals, especially inthe study of cell tracking, cancer metastasis. In practice, unstablebackground signals exist in IVFC data due to animals’ respiratory
movement, limb movement and photo-bleaching of tissueauto-fluorescence. Here we developed a processing methodthat could remove baseline drift using interpolation fitting,automatic segmentation and wavelet denoising. Compared withprevious non-correction methods, i.e. the “line-gating” methodor threshold method, this method showed higher sensitivity andspecificity, as well as better Pearson’s correlation coefficient andmean-squared error (MSE).

10024-14, Session 3

Microwave-induced thermoacoustic
imaging system based on flexible
transducer
Zhong Ji, Sihua Yang, Da Xing, South China Normal Univ.
(China)Microwave-induced thermoacoustic (TA) imaging combines theadvantages of high imaging contrast due to electromagnetic
absorption and high resolution of the ultrasound technology,
and it is a potential alternative imaging technique for biomedical
applications, particularly for breast tumor detection. The
traditional TA system uses circular-scanning (CS) to obtaincomplete information to reconstruct a two-dimensional image,
however, it needs a large operating space for rotation of thetransducers and bulk of coupling medium limiting its medical
applications. The linear-scanning (LS) system can overcome
these problems partially but usually lose some information andcause image distortion. In this paper, in order to overcome above
limitations, a TA imaging system with Sample-Cling-Scanning(SCS) model based on a ﬂexible multi-element transducer ispresented. It combines the advantages of both CS and LS modes,
and overcome their limitations. Meanwhile, an adaptive backprojection algorithm is presented to implement this scanningmodel. The experimental results show that the proposed system
combines advantages including shape adaptation, information
integrity, and efficient transmission. These advantages make it apreferred system for TA applications, especially in breast tumor
detection.

10024-15, Session 3

Evaluation of the resolution of acommercial swept source OCT using point
spread function phantom
Wei Gong, Weijun W. J. Li, Kui Dong, Shusen Xie, Zheng
Huang, Fujian Normal Univ. (China)
Optical coherence tomography (OCT) is a useful tool inbiomedical imaging. For structural imaging it is equally important
to improve the resolution of OCT system and to accurately assess
the sizes of structural components of inhomogeneous biologicaltissues from OCT images. Recently, point spread function(PSF) phantoms with randomly distributed nanoparticles in atransparent matrix have been used for evaluating the resolution
and image quality of OCT. In this study, iron oxide particles

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Follow us on:embedded in polyurethane was used as the PSF phantom forobjectively evaluating the resolution of a commercial modelof swept source OCT. The density of iron oxide particles wasapproximately 7500 per mm3. For assessing and comparing
the performance of the OCT system, OCT images of the PSF
phantom were obtained, 3D spatial variations in PSF intensity,and FWHM in the axial and lateral directions in combination withvolumetric representations of individual PSF were analyzed. Test
results suggest that the PSF phantom is a reliable means for theintercomparison of OCT resolution and assessment of the sizes ofsome biological samples.

10024-16, Session 3

Second-generation photoacoustic andoptical coherence tomography probe forin vivo human vasculature visualization
Mengyang Liu, Christoph Sinz, Zhe Chen, Behrooz
Zabihian, Harald Kittler, Wolfgang Drexler, Medizinische
Univ. Wien (Austria)
Both photoacoustic tomography (PAT) and optical coherence
tomography (OCT) are comparatively novel optical imaging
modalities for biophotonics. The combination of a swept source
OCT (SS-OCT) system with an all optical detection PAT system
has been developed and demonstrated from ex vivo embryonic
imaging to in vivo human imaging. While morphologicalvolumes provided by OCT in the optical mean free path hascomplemented the PAT volumes which show the major bloodvessels, PAT’s low spatial resolution makes it not capable ofvisualizing the microvasculature in the first mm in tissue. OCT
angiography, therefore, has been explored in the combined PAT/OCT system to visualize capillaries. The first generation system
uses a probe mounted on a modified microscope boom standand has been shown to be able to apply to different parts ofhuman body. However, the articulated arm and the probe withrecessed sensor holder limits its application in clinics. It requires
high level of patient compliance and the location to be imaged
is restricted. In our second generation design, a homemade
rack with a medical bed has been manufactured along withlimb fastening vacuum pad for human extremity fixation. The
probe can be adjusted in multiple dimensions with accuracy.
The protruding sensor holder design also permits imaging in
flattened regions of skin. With the options to either seat orlay the patient, our second generation PAT/OCT system gives
unprecedented versatility in clinical applications. Both healthy
subjects and patients with skin diseases are imaged using oursecond generation PAT/OCT system to demonstrate its clinicalsignificance.

10024-17, Session 3

All-optically integrated multimodality
imaging system: combined photoacoustic
microscopy, optical coherence
tomography, and fluorescence imaging
Zhongjiang Chen, Sihua Yang, Da Xing, South China
Normal Univ. (China)
We have developed a multimodality imaging system by opticallyintegrating all-optical photoacoustic microscopy (AOPAM),
optical coherence tomography (OCT) and fluorescencemicroscopy (FLM) to provide complementary information
including optical absorption, optical back-scattering andfluorescence contrast of biological tissue. By sharing the same
low-coherence Michelson interferometer, AOPAM and OCT could
be organically optically combined to obtain the absorption andscattering information of the biological tissues. Also, owing#PhotonicsAsia

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
to using the same laser source and objective lens, intrinsicallyregistered photoacoustic and fluorescence signals are obtained
to present the radiative and nonradiative transition process ofabsorption. Simultaneously photoacoustic angiography, tissue
structure and fluorescence molecular in vivo images of mouseear were acquired to demonstrate the capabilities of the opticallyintegrated trimodality imaging system, which can present more
information to study tumor angiogenesis, vasculature, anatomical
structure and microenvironments in vivo.

10024-18, Session 3

Extinction measurement of dense media
by an optical coherence tomography
techniqueToshiaki Iwai, Tomoki Ago, Ryoko Yokota, Tokyo Univ. ofAgriculture and Technology (Japan)
Absorption-scattering imaging by an optical-coherence
tomography (OCT) technique has been investigated forbiological tissues. The Beer-Lambert law as a function of pathlength of the light propagated in a dense medium is applied
to estimate amount of extinction. Since multiple scattering
becomes dominant in the biological tissue, the path-length ofthe light scattered in the tissue cannot be obtained uniquelyand deterministically. Therefore, a total path-length estimated inadvance by the Mote Carlo simulation is applied to the modified
Beer-Lambert law. On the other hand, the OCT image of thebiological tissue can be reconstructed by using only the lightpropagated rectilinearly and retro-reflected from scatters which
preserves its coherence. Therefore, the OCT technique will beavailable to measure absorption and scattering coefficients evenfor the dense medium directly by using the Beer-Lambert law. It,
however, has not yet been experimentally confirmed that the BLlaw is effective for diffusing light by multiple scattering as longas we know. The quantitative verification of BL-law in the OCT
imaging is experimentally conducted in in this study. As a result,
it is shown that the scattering and absorption coefficients can be
successfully estimated for phantoms composed of silica particles
with a given size as a scatterer and ink as an absorber.

10024-19, Session 4

A microflow cytometer with integrated
on-chip optical components for blood cell
analysis (Invited Paper)
Yingying Zhao, Qin Li, Xiaoming Hu, Beijing Institute ofTechnology (China)
In recent years, microfluidic technologies have shown the great
potential in developing portable, point-of-care testing (POCT)
blood cell analysis devices. It is challenging to integrate all freespace detecting components in a single microfluidic platform. In
this paper, a microflow cytometer with integrated on-chip opticalcomponents was demonstrated. To facilitate on-chip detection,
the device integrated optical fibers and on-chip microlens withmicrofluidic channels on one polydimethylsiloxane (PDMS)
layer by standard soft photolithography. This compact design
increased the sensitivity of the device and also eliminated timeconsuming free-space optical alignments. Polystyrene particlesof 4?m, 6?m, 10?m diameter, together with erythrocytes andplatelets, were measured in the microflow cytometer by small
angle forward scatter light. Experimental results indicated thatthe performance of the microflow device was comparable toa conventional cytometer, and also demonstrated its ability todetect on-chip optical signals in a highly compact, simple, truly
portable and low cost format which was perfect suitable for
POCT clinical haematology diagnostics.

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10024-20, Session 4

A weighted optimization method forirradiance distribution planning of port
wine stains with photodynamic therapy
Linhuan He, Xiaoming Hu, Ya Zhou, Beijing Institute ofTechnology (China)
Planning of irradiance distribution (PID) is one of the foremost
factors for on-demand treatment of port wine stains (PWS) withphotodynamic therapy (PDT). A weighted optimization method
for PID was proposed according to the grading of PWS withthe help of a three dimensional digital illumination instrument,
which would improve the treatment efficacy in each session of
PDT. First, the point clouds for three dimensional reconstruction
were filtered to remove the error points and redundant points,
the triangulation was carried out and the lesions was divided into
many small triangular patches. The parameters for optimizationof each triangular patch such as area, normal vector andorthocenter were calculated from the triangulation results. The
weight coefficients were determined by the erythema indexes
and areas of patches. Then, the initial point was calculated basedon the normal vectors and orthocenters to optimize the light
direction. The irradiation can be optimized according to cosine
values of irradiance angles and weight coefficients. Comparing
the irradiance distribution before and after optimization, theproposed weighted optimization method can make the irradiancedistribution match better with the characteristics of lesions, andhas the potential to improve the therapeutic efficacy.

10024-21, Session 4

Macroscopic singlet oxygen modeling forin vivo Photofrin-mediated photodynamic
therapy dosimetry study
Haixia Qiu, Chinese PLA General Hospital (China) andUniv. of Pennsylvania (United States); Michele M. Kim,
Univ. of Pennsylvania (United States); Rozhin Penjweini,
Timothy C. Zhu, The Univ. of Pennsylvania Health System(United States)
Although photodynamic therapy (PDT) is an established modality
for the cancer treatment, the ideal dosimetric predictor for PDT
outcome is still unavailable. As the primary cytotoxic factor
responsible for tumor destruction in the type II reaction, singlet
oxygen (1O2) dosimetry deserves more consideration. In this invivo study, a macroscopic singlet oxygen model was adopted
to evaluate the ability of the calculated reactive singlet oxygen([1O2]rx) as a dosimetric predictor for the outcome of Photofrinmediated PDT. Mice with radiation-induced fibrosarcoma (RIF)
tumor were subjected to PDT of different fluence (50, 135, 200
and 250 J/cm2) under different fluence rate (50, 75 and 150
mW/cm2). Tumor regrowth rate (k) was calculated by fitting
the measured tumor volume to an exponential growth equation.
By incorporating Photofrin concentration and the tissue opticalproperties as well as light dose (fluent rate and fluence) into themacorscopic singlet oxygen model, [1O2]rx was calculated. Then,the tumor cure index was correlated to the calculated [1O2]rx,
the light fluence and PDT dose, respectively. The result showedamong these three metrics, [1O2]rx had the best correlation withthe tumor cure index with the R2=0.93. These preliminary results
suggest that [1O2]rx could serve as a better dosimetric predictor
for predicting PDT outcome.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-22, Session 4

Stage scoring of liver fibrosis using
Mueller matrix microscope
Jialing Zhou, Tsinghua Univ. (China); Honghui He, Ye
Wang, Hui Ma, Graduate School at Shenzhen, Tsinghua
Univ. (China)
Liver fibrosis is a common pathological process of varied chronic
liver diseases including alcoholic hepatitis, virus hepatitis, and soon. Accurate evaluation of liver fibrosis is necessary for effective
therapy and a five-stage grading system (F0-F4) was developed.
Currently, experienced pathologists use stained liver biopsies
to assess the degree of liver fibrosis. However, it is difficult toobtain highly reproducible results because of discrepancy among
different observers. Polarization imaging technique has thepotential of scoring liver fibrosis since it is capable of probing
the structural properties of samples. Considering that the Mueller
matrix measurement can provide comprehensive microstructural
information of the tissues, in this paper, we apply the Mueller
matrix microscope to human liver fibrosis slices in different
fibrosis stages. We adopt the Mueller matrix polar decomposition(MMPD) and Mueller matrix transformation (MMT) parameters
for quantitative analysis. We also use the Monte Carlo simulation
to study the method to remove orientation dependence ofthe Mueller matrix, and analyze the relationship between the
microscopic Mueller matrix parameters and structural changes
during the fibrosis process. The experimental and Monte Carlosimulated results show good consistency. The parameters
corresponding to retardation increase and the distribution of
the fast axis angle becomes more concentrated as the liver
fibrosis getting more serious. The results presented in this paper
indicate that the Mueller matrix microscope and the orientation
independent Mueller matrix parameters can provide additional
information for the detections and fibrosis scorings of livertissues. Thus, it has a good application prospect in liver fibrosis
diagnosis.

10024-23, Session 4

3D printing of tissue-simulating phantoms
for calibration of biomedical opticaldevicesZu Hua Zhao, Ximing Zhou, Shu W. Shen, Guang Li Liu, Li
Yuan, Yu Q. Meng, Xiang Lv, Peng Fei Shao, Erbao Dong,
Univ. of Science and Technology of China (China); Ronald
X. Xu, The Ohio State Univ. (United States)
Clinical utility of many biomedical optical devices is limited by
the lack of effective and traceable calibration methods. This
limitation induces the pressing need for a phantom standard
to calibrate medical optical devices. Optical phantoms thatsimulate biological tissues have been explored for optical device
calibration in clinical settings. Various optical phantoms arefabricated by the methods such as mold casting, spin coating and
3D printing. However, these phantoms can hardly simulate both
structural and optical properties of multi-layered biological tissue.
To address this limitation, we develop a 3D printing production
line that integrates different rapid manufacturing processes forfreeform fabrication of optical phantoms with mechanical andoptical heterogeneities. The production line consists of a threedimensional mobile platform and different modules for spin
coating, light-cured 3D printing and Fused Deposition Modeling(FDM) respectively. With the Polydimethylsiloxane (PDMS),
colorless light-curable ink?and gel wax as matrix materials,
titanium dioxide (TiO2) powder as the scattering ingredient,graphite powder and black carbon as the absorption ingredient,a multilayer phantom with high-precision is fabricated. The
absorption and scattering coefficients of each layer are measured

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by a double integrating sphere system. The results demonstratethat the system has the potential to fabricate reliable tissuesimulating phantoms to calibrate optical imaging devices.

10024-24, Session 4

Effect of surface topographic features on
the optical properties of skin: a phantom
study
Guang Li Liu, Jian Feng Chen, Yilin Han, Zu H. Zhao, Gang
Zhao, Erbao Dong, Univ. of Science and Technology ofChina (China); Ronald X. Xu, The Ohio State Univ. (UnitedStates)Tissue-simulating phantoms are used to validate and calibrate
optical imaging systems and to understand light transport inbiological tissue .Light propagation in a strongly turbid medium
such as skin tissue experiences multiple scattering and diffuse
reflection from the surface. Surface texture and roughness haveconsiderable influence on the optical characteristics of skin.
Surface roughness introduces phase shifts and optical path
length differences for light scattered within the skin tissue andthat reflected from the surface. In this paper, we study the effectof mismatched surface roughness on optical measurement andsubsequent determination of optical properties of skin tissue. A
series of phantoms with controlled surface features and opticalproperties corresponding to normal human skin are fabricated.
The fabrication of polydimethylsiloxane (PDMS) phantoms withknown surface roughness follows a standard soft lithography
process. Surface roughness of skin-simulating phantoms aremeasured with optical stylus profiler. To obtain single layer
equivalent skin tissue ,the thickness (between 9 and 370 ?m)is controlled using a spin coater. The diffuse reflectance of thephantom is validated by a UV/VIS spectrophotometer .The
results show that surface roughness plays an important role inthe determination of optical properties of phantoms .This study
suggests that surface roughness should be considered as animportant contributing factor for the determination of tissue
optical properties.

10024-25, Session 4

Structured light imaging system forcharacterization of tissue-simulating
phantoms
Songde Liu, Yilin Han, Shu Wei Shen, Zu Hua Zhao, Peng
Liu, Kai Qin Chu, Zachary J. Smith, Univ. of Science andTechnology of China (China); Ronald X. Xu, The Ohio State
Univ. (United States)
The pressing need for a phantom standard to calibrate medical
optical devices has made 3D printing of tissue-simulating
phantoms one of the hotspots and difficulties in 3D printing field.
Its difficulties include not only how to print the tissue-simulating
phantoms but also how to characterize them. Measurement
tools such as computed tomography (CT), optical coherence
tomography (OCT), magnetic resonance imaging (MRI), and step
profiler has been used to characterize the phantoms’ internal
structure or external profile; double-integrating sphere system,
frequency domain photon migration technique (FDPM) has beenused to characterize the phantoms’ optical properties. But noneof them can characterize both 3D profile and optical properties
at the same time. To overcome this limitation, we develop a
structured light imaging system which can characterize both
3D profile and optical properties at the same time with thesame set of equipment. The system consists of a hyperspectral
light source, digital light projector (DLP), CCD/CMOS camera,#PhotonicsAsia

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Conference 10024:
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rotational platform, and two polarizers. We choose doubleintegrating sphere system to characterize our system’s ability inreconstruction of optical properties. The results show that thesystem can get a pixel-level optical properties with an error ofwithin 10%. At the same time, an accuracy of submillimeter of 3D
profile can be retrieved from this system. All of this demonstratethat our system has the potential to characterize homogeneousand even heterogeneous tissue-simulating phantoms.

10024-28, Session 510024-26, Session 4

The brain is the most complex and significant organ, but little
is known about the mechanisms of brain function yet. Brainfunctions rely primarily on neuronal networks rather than on
individual neurons, thus we promote the Visible Brain-wide
Networks (VBN) project covering neuron morphology, neuronal
circuits, cyto-architecture and vascular networks, which is thebasis of understanding the brain function.

1040nm femtosecond fiber laser system
for the regain accommodation of thecrystalline lensLifeng Wang, Jiaying Zhang M.D., Chinese PLA General
Hospital (China); Zhiguo Lv, Institute of Physics (China);
Zhiyi Wei, Institute of Physics (China) and Chinese PLA
General Hospital (China); Ying Gu, Chinese PLA General
Hospital (China) and Institute of Physics (China)
Presbyopia is the diminished ability of eyes to focus on near
objects, which happens to every human with growing age.
The origin of the presbyopia is the loss elasticity of the lensdue to the increasing sclerosis. Femtoseocnd laser which has
achieved great success in the refractive surgery, is applied in the
crystalline lens to regain the accommodation of the lens tissues.
We have build an femtosecond fiber laser based on the chirped
pulse amplification technology. An femtosecond fiber oscillatordelivers 1040 nm laser pulses with compressed pulse durationof 150 fs. After three stages of amplification, and compressedby a two-pass configuration grating, femtosecond laser pulses
with pulse energy of 3 ?J, pulse duration of 400 fs at 200 kHz
are achieved. In order to create structure in the crystalline lens,a three dimensional scan system is constructed, which consistsof a telescope, an aspherical lens, a galvanometric scanner and atranslation stage. Since the diameter of the femtosecond is 3 mm,
the telescope and the an aspherical lens are employed to improve
the focus quality. While the galvanometric scanner is used togenerate a two dimensional scan in the crystalline lens, and thetranslation stage where the crystalline lens is mounted adds
another movement direction. The integrated system can performthe three dimensional cut in the crsytalline lens with a foucs of
25 ?m diameter. The whole system is easy to start, insensitive tooutside distortions and can be improved for clinical use.

Simulation study of haze weather basedon particle system
Jiwei Ning, Beijing Univ. of Posts and Telecommunications(China)Since 2013, the haze weather was more and more serious. Haze
weather has produced great harm on human health and traffic
safety. Effectively to predict the interval of the haze weather
pollution, pollution degree, realize the real-time simulation ofhaze weather, for the environment protection, human health,preventing traffic accidents, improving labor productivity andso on all is of great significance. Based on the analysis of thecharacteristics and causes of haze weather, using the particle
system and texture mapping and optical principle , I establishedthe mathematical model for describing the haze weather. Using
OSG (OpenSceneGraph), I has realized the real-time simulation
and analysis of haze weather.

SPIE Photonics Asia·

Qingming Luo, Huazhong Univ. of Science and Technology(China)We obtained the dataset of whole mouse brain with MicroOptical Sectioning Tomography (MOST) system at single-neuron
resolution which directly demonstrates the whole-brain structuralconnectivity. After data collection, we developed a pipeline toreconstruct the complete morphology and long-range projectionof neuron. Meanwhile, from the Nissl-stained dataset, we canalso get the division of brain regions and nuclei based on cytoarchitecture and the blood vessel. Based on the accumulated
dataset, we can perform analysis and simulation, even it isbeneficial to artificial intelligence.
However, we also met many challenges. The big data problem
is the most troublesome one. We need to develop new methodfor data compression and high performance computing. Anotherchallenge is about the highly complex structure, there are large
number of numerous types of neurons, the morphology of someneurons is so intricate. Therefore, we also need to fully optimize
and accelerate the reconstruction algorithm.
The VBN project is aimed at providing a research platform, after
that, we can perform analysis and simulation the complex brain
function from bottom to top, by the method of reductionism.

10024-29, Session 5

Recent advances in fluorescence lifetime
imaging: superresolution, single particle
tracking, and some novel applications(Invited Paper)
Wei Yan, Qianqian Wu, Jing Qi, Shuyi Yuan, Teng Luo,
Shaozhuang Yang, Xiao Peng, Danying Lin, Junle Qu,
Shenzhen Univ. (China)

10024-27, Session 4

136

Challenges of large-scale data processing
for visible brain-wide networks (Invited
Paper)

Fluorescence microscopy is a widely used tool in biomedicine.
Unlike fluorescence intensity, fluorescence lifetime depends onthe micro-environment of fluorophores. There are a number ofparameters that can influence fluorescence lifetime, such as local
viscosity, pH, refractive index, oxygen saturation and protein
binding. Fluorescence lifetime imaging (FLIM) offers the ability
to discriminate between tissue fluorophores on the basis of
their characteristic emission lifetimes. As an established imaging
method, FLIM analysis can provide clues to diseased intracellular
activity at subcellular resolution, further improving diagnostic
accuracy. Recently, FLIM techniques have been broadly applied toimaging and characterization of biological tissues.
This presentation will introduce the principles of FLIM andpresent our recent work in FLIM, including superresulution
FLIM through stimulated emission by depletion (STED), thecombination of lifetime measurement with single particle
tracking, and some applications of FLIM in tissue discrimination.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-30, Session 510024-32, Session 5

Spectral Domain Optical Coherence
Tomography with Extended Depth-offocus by Aperture Synthesis

Lensless quantitative phase imaging basedon ptychographic iterative engine withpartially-coherent illumination

En Bo, Linbo Liu, Nanyang Technological Univ. (Singapore)

Wei Yu, Xiaolin Tian, Xiaoliang He, Shouyu Wang, Cheng
Liu, Jiangnan Univ. (China)

We developed a novel depth-encoded FD-OCT system withan extended depth-of-focus (DOF) using multiple aperturesynthesis. Multiple aperture synthesis can achieve equivalentlateral resolution along an extended DOF by correcting thedefocus-induced wavefront curvature. For a designatedGaussian-shape light source, the lateral resolution is determinedby the numerical aperture (NA) of the objective lens and can beapproximately maintained over the confocal parameter, which
is defined as twice the Rayleigh range. However, the DOF is
proportional to the square of the lateral resolution. Consequently,
a trade-off exists between the DOF and lateral resolution, andresearchers have to weigh and judge which is more important
for their research reasonably. In this paper, we reported a novel
multiple aperture synthesis method for DOF extension. In thisstudy, multiple distinct optical apertures can be achieved byimbedding an aperture synthesis element (ASE) in the sample
arm. Due to the optical path difference between multiple distinct
apertures caused by ASE, multiple images will be aligned alongz-axis vertically. By correct the OPD and defocus-induced
wavefront curvature, multiple images with distinct depths will
be coherently summed together. By correcting the optical path
difference and defocus-induced wavefront curvature, images
with distinct aperture were coherently summed together. Thissystem digitally refocused the sample and obtained a brand newimage with nearly the same lateral resolution over an extended
DOF, which was multiple times more than the confocal parameter
when imaging the polystyrene calibration particles.

10024-33, Session 510024-31, Session 5

Optimization of wide-field large-volume
tomography to accelerate whole-brain
imaging
Qiuyuan Zhong, Xiaoyu Zhang, Zhangheng Ding, Sile An,
Jing Yuan, Hui Gong, Qingming Luo, Britton Chance Ctr.
for Biomedical Photonics (China)
Fast imaging a mammalian brain in 3D at single-axon resolution
is crucial to reconstruct and analyze neural morphology andconnectivity. However, even the latest wide-field large-volume
tomography (WVT) takes more than 3 days to acquire a 3D
dataset of whole mouse brain at a voxel size of 0.32 ? 0.32 ? 2.0?m. So long data acquisition time of whole-brain imaging limits
potential applications of the technology. Here, we optimize thedata acquisition and uploading strategies of the WVT technology,
respectively, to accelerate imaging a whole brain. We optimize
acquisition flow and adjust time distribution in single imagingsectioning circle to decrease total time consume. Automatedexposure adjustment is employed to reduce exposure time
according to signal intensity layer by layer. Different image
compression formats are compared to choose the fit to shorten
image saving time and image size. We also introduce automatedcontour identification to define minimized imaging range
according to brain contour in real time, avoiding redundant dataacquisition and saving. All of these efforts totally improve 20%of the data acquisition time of WVT, from 77 hours to 62 hours.
In addition, we employ real-time data packing to accelerate
data uploading after data acquisition. The data uploading timeis shortened from 12 hours to 5 hours. The optimized WVT
potentially becomes a routine tool of neural connectome andprojectome.

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As an ideal phase microscopic method for imaging with shortwavelength including x-ray and electron beam, Ptychographic
Iterative Engine (PIE) is widely applied due to its advantages.
However, the traditional PIE algorithm requires a purely coherent
illumination. Since the coherency of x-ray and electron beam isalways much lower than that of the laser, it is high of importanceto develop a new algorithm for PIE to enhance its capability
in handling the partially coherence. In this paper, an improved
polyPIE algorithm is developed to realize the high resolution
phase imaging under partially coherent illumination by taking theshape of the illuminating pinhole and the spectral distributionof the light source into the iterative computation. Duringreconstructing the amplitude and phase of the sample, theshape of the pinhole forming the illumination is used as the same
spatial constraint for all the reconstructed probes on the pinhole
plane. With this method, a much high convergence speed andreconstruction accuracy can be achieved as well as a wide view
field. The influence of the spectral width to the reconstruction
accuracy is also analyzed in this paper. When the width of theincoherent illuminating source is smaller than 10% of the central
wavelength, the polyPIE algorithm can accurately reconstruct
the phase and modulus images of the object, otherwise, theconvergence speed and reconstruction accuracy will become
remarkably lower. This method also can be widely used in other
CDI field with partially coherent illumination.

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Determination of the real focal plane withtransport intensity equation and wavefront
propagation method
Xin Meng, Xiaolin Tian, Wei Yu, Jiangnan Univ. (China);
Liang Xue, Shanghai Univ. of Electric Power (China);
Cheng Liu, Shouyu Wang, Jiangnan Univ. (China)
Microscopy combining with transport intensity equation isan effective method which only needs in-focus and defocus
images to retrieve both the phase and the intensity of a sample.
However, in practical TIE measurements, errors are induced
since the position of the in-focus image is chosen artificially.
Halos and blurs decrease the imaging quality as well as theaccuracy in phase measurement. In order to obtain in-focus
quantitative intensity and phase distributions of samples,
numerical wavefront propagation is proposed combining withfocal determination criteria. In our method, three images arecaptured, then amplitude and phase distributions at center plane
are retrieved with transport intensity equation. Using algorithm
based on wavefront propagation, both intensity and phase
distributions at different positions with adjacent interval of 0.1
mm near the chosen center plane can be obtained. To seek the
in-focus position from a series of numerical obtained wavefront,
focal determination criteria based on the cellular duty ratio isdesigned and adopted. In experiment, the real focal plane canbe accurately determined within an wide range from -40 mm
to 40 mm. Additionally, the correlation coefficients between
the intensities of real and numerical retrieved are higher than
0.95 indicating the proposed method not only can catch thereal focal plane, but also provide clear images without any
hardware alterations. It is believed that the proposed method
reduces the dependence of accurate focal plane choosing in#PhotonicsAsia

137

Conference 10024:
Optics in Health Care and Biomedical Optics VII
TIE measurements and owns the potentiality in automatic focal
determination in microscopic imaging.

in-focus location and information can be obtained with highaccuracy and fast speed.

10024-34, Session 610024-36, Session 6

Tissue optical clearing for enhancement ofin vivo blood flow imaging (Invited Paper)

Contrast improvement for swept source
optical coherence tomography image of
sub-surface tissue

Dan Zhu, Huazhong Univ. of Science and Technology(China)The tissue optical clearing (TOC) technique could significantly
improve the biomedical optical imaging depth, but mostcurrent investigations are limited to in vitro studies. For in vivo
applications, the TOC method must provide a rapid treatment
process, sufficient transparency, and safety for animals, whichmakes it more difficult. Recently developed innovative opticalclearing methods for in vivo use show great potential forenhancing the contrast and resolution of blood flow imaging.
This paper gives an overview of recent progress in the use of
TOC for vascular visualization. First, this presentation introducestransparent windows, including various skin windows and acranial window, that permit Laser speckle imaging to monitor
dermal or cortical blood flow, respectively, with high resolution
and contrast. We demonstrate the capability of the combination
method of LSCI and skin optical clearing to describe in detailthe dynamic response of cutaneous vasculature to vasoactive
noradrenaline injection. Moreover, the superior resolution,
contrast and sensitivity make it possible to rebuild arteries-veinsseparation and quantitatively assess the blood flow dynamicalchanges in terms of flow velocity and vascular diameter at single
artery or vein level.

Swept source optical coherence tomography (SSOCT) is an
attractive biological imaging technology due to its advantagesof simple setup and high imaging speed. As the light intensity
attenuated rapidly in high scattering biological tissues, thecontrast of OCT image will drop with depth. In this paper a
new method was introduced to compensate the attenuation ofimaging contrast in SSOCT. The interference signal was divided
into two channels of analog to digital converter (ADC) with asplitting ratio of 1:5. The stronger signal was used to reconstructdeep structure of tissue and the weaker signal was used toreconstruct surface structure of tissue. The low frequencies
in the stronger channel were filtered to make full use of themeasurement range of ADC, the combined OCT image will obtaina higher signal intensity in the imaging range and the contrastof system will be improved. A tape, human nail and porcine
windpipe were used to test capacity of our method. OCT images
obtained by a SSOCT system were reconstructed with twochannels method. Results show the contrast of structures in OCT
images has been improved, especially in deep region.

10024-37, Session 610024-35, Session 6

Large virtual histology using confocal
microscopy

High-speed phase-based auto-focusing
method with transport of intensity
equation and numerical wavefront
propagation
Xiaolin Tian, Xin Meng, Wei Yu, Jiangnan Univ. (China);
Liang Xue, Shanghai Univ. of Electric Power (China);
Cheng Liu, Shouyu Wang, Jiangnan Univ. (China)
As a non-interferometric technique, the transport of intensity
equation (TIE) phase imaging shows great potentials in various
fields. Traditionally, phase retrieval from TIE can be realized only
by capturing single in-focus image and two defocused ones
symmetrically. However, during experimental measurements, thefocal plane is often chosen artificially, which may induce errors
and blurs in retrieved phase and intensity. Though combining
with numerical wavefront propagation and focal determination
criteria, both in-focus position and intensity can be acquired,unfortunately, considering the high-frequency loss in angular
spectrum algorithm, details in the samples are lost which severely
decrease the imaging quality, as well as the retrieved information.
Moreover, with numerical calculations based imaging plane
scanning, a great deal of calculation is needed indicating longtime consuming and low calculation efficiency. In order to acquire
the high-accurate in-focus information, as well as realize fast focal
plane seeking, in this paper, dichotomy method is introduced
which can greatly reduce computing time of focal determination.
Moreover, after obtaining the focal plane, the imaging recorder istranslated to that plane to capture the real intensity distribution
physically. Proved by practical measurements, even the bias
imaging plane is 30 mm away from the real focal plane, thefocal plane can be obtained with the error less than 0.05 mm.
Additionally, the focal seeking efficiency is raised by 50 times
because of the application of the dichotomy method. It isbelieved with this phase based auto-focusing method, both the138

Xinyu Li, Shanshan Liang, Jun Zhang, Sun Yat-Sen Univ.
(China)SPIE Photonics Asia·

JueHyung Kang, Hanyang Univ. (Korea, Republic of);
HongRae Kim, National Cancer Ctr. (Korea, Republic of);
Incheon Song, NanoScope Systems, Inc. (Korea, Republicof); Hyeong Soo Nam, Hanyang Univ. (Korea, Republicof); Hyunjin Kim, S. H. Lee, National Cancer Ctr. (Korea,
Republic of); Young Jae Won, Osong Medical Innovation
Foundation (Korea, Republic of); Yongdoo Choi, Hee Jin
Chang, Kwang-Gi Kim, Dae Kyung Sohn, National Cancer
Ctr. (Korea, Republic of); Hongki Yoo, Hanyang Univ.
(Korea, Republic of)Confocal microscopy was used due to its ability to opticallysection fresh tissue. Confocal images were acquired using a
multichannel confocal microscope setup. The system uses a 20x
objective and a confocal imaging chamber for imaging. Rasterscanning was done using Galvano mirrors for x and y scan.
Hoechst 33342 (Ex.300-410nm/Em.390-620 nm) and Eosin(Ex.300-560nm/Em.510-700nm) were used as fluorescent dyes
to stain nuclei and cytoplasm respectively. 405 nm and 488 nm
lasers were used as excitation light source for each fluorescentdyes. Normal tissues and tumor tissues were collected froma mouse. Normal liver, stomach, lung and kidney tissues wereacquired. Tumor tissues were acquired by grafting SSC7 cell lines
under the skin of the mouse. The acquire tissues were cut into
sizes of around 5x5 mm. Images were acquired simultaneously
and serially to observe any crosstalk between channels. Image
mosaics were created using a mechanical stage. Acquired images
were then stitched together using a stitching algorithm provided
by the National Institutes of Health. It took around 5 minutes toacquire a 9x9 mosaic image which equals to size of around 4x4mm2. H&E colormap was created from the RGB values of a frozen
histology image. Using the H&E colormap, grayscale confocal

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
images were converted to resemble frozen histology. Acquired
confocal images were validated with matching frozen histology.
Using the technique, physicians can examine potentiallymalignant lesions much quickly than the conventional H&E
staining and decide a treatment plan within the surgical room.

diffuse reflectance spectroscopy method for practical liquidcomposition analysis. This research provided a new thinking ofpractical turbid liquid composition analysis.

10024-38, Session 6

Research of transmissive near-infrared
spectroscopy for non-invasive blood
glucose measurement

A frequency domain 4-frame SIM
reconstruction algorithm
Amit Lal, Xiaoshuai Huang, Peng Xi, Peking Univ. (China)
Conventionally, super resolution image reconstruction from
Structured Illumination Microscopy (SIM) is carried out using
nine raw images (Heintzmann and Cremer, 1999; Rego et al.,2012; Shroff et al.,2010; Wicker et al., 2013). Recently, in order
to increase the frame rate, attempts are made to carry out
SIM reconstruction by using reduced number of raw images.
Successful reconstructions of SIM images are demonstrated byutilizing as low as 4 raw images (Orieux et al., 2012; Dong et al.,2015). The reconstruction method employed while utilizing 4
raw images differs from that employed in conventional SIM in
two key aspects: (1) The reconstruction is carried out in spatial
domain. In contrast, conventional 9-frame SIM reconstruction iscarried out in Fourier domain. (2) An iterative algorithm is used
to arrive at the reconstructed image. Conventional 9-frame SIM
reconstruction provides a single-step (closed-form) solution!
These differences raise curious questions, for instance: Is it
not possible to carry out 4 frame SIM reconstruction using
conventional approach in Fourier domain? Or is it that thereconstruction methodology in Fourier domain suffers severe
inherent disadvantages, which justifies preference for spatial
domain reconstruction in published literature? The present work
is motivated by these curious questions.
In this manuscript, we describe a SIM reconstruction algorithm
which utilizes 4 raw images (1 wide-field and 3 SIM images)
and carries out the reconstruction process in Fourier domain.
The reconstruction provides a single-step (closed-form)
solution, just as the case with conventional 9-frame SIM
reconstruction. Subsequently, the operation of devised 4-frame
SIM reconstruction algorithm is tested on simulated raw data forvaried noise levels. Results obtained suggests that for low noiselevel (<10%) 4-frame SIM reconstruction algorithm produces
images comparable to that obtained by conventional 9-frame
SIM reconstruction algorithm; however, the results begin to
deteriorate at higher noise levels.

10024-60, Session Post

Hemoglobin concentration determination
based on near-infrared spatially-resolved
transmission spectra
Linna Zhang, Ling Lin, Gang Li, Tianjin Univ. (China)
Spatially resolved diffuse reflectance spectroscopy method has
been proved to be more effective than single point spectroscopy
method in the experiment to predict the concentration of theIntralipid diluted solutions. However, Intralipid diluted solution
is simple, cannot be the representative of turbid liquids. Bloodis a natural and meaningful turbid liquid, more complicate.
Hemoglobin is the major constituent of the whole blood. And
hemoglobin concentration is commonly used in clinical medicine
to diagnose many diseases. In this paper, near infrared spatiallyresolved transmission spectra (NIRSRTS) and Partial Least
Square Regression (PLSR) were used to predict the hemoglobin
concentration of human blood. The results showed the prediction
ability for hemoglobin concentration of the proposed method
is better than single point transmission spectroscopy method.
This paper demonstrated the feasibility of the spatially resolved

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10024-61, Session Post

Wen-Ming Yang, Ningfang Liao, Yasheng Li, Liwei Shao,
Dehuang Huang, Beijing Institute of Technology (China)
Near infrared (NIR) spectrum can be used to analysis the opticalproperties of human blood components. Non-invasive blood
glucose measurement using NIR transmittance or reflectance isfeasible for diabetic patients to know the level of blood glucosetightly. However, the spectrum changing level caused by uniqueglucose absorption is hard to identify due to other blood
components and low signal-to-noise (SNR). In this work, wedelivered a non-invasive glucose detection system with Fouriertransform spectrometer which will work in fingertips or otherhuman body tissues. The measurement system mainly consistsof a Sagnac interferometer, a refrigerated InGaAs detector, a NIR
LED light source and a Fourier transform spectrum analyzing
system. The InGaAs detector with high quantum efficiency
performing well in the range of 1.0-1.7?m wavelength is used
to acquire transmissive radiation. We have focused on the
explorations on the NIR spectral bands known to be dominatedby the glucose absorption information. Preliminary experiment
investigations were set up to test glucose levels of fingertips andaqueous solutions with different concentrations. SNR of spectral
information recorded in the interference fringes is improved byusing refrigerated InGaAs detector. The analytical modeling of
the interference pattern is based on arithmetic Fourier transformand supported by the curvilineal characterization. Experimental
results show the variation of light intensity among different
glucose concentrations and emphasize the obvious absorptionof glucose in NIR wave-range. This study confirms the suitability
that NIR can be developed in non-invasive glucose measurement.

10024-62, Session Post

Amplitude enhancement by a gold dimer
Xin Hong, Jingxin Wang, Zheng Jin, Dalian Univ. ofTechnology (China)
The unique optical properties such as brightness, non-bleaching,good bio-compatibility make gold particles ideal label candidates
for molecular probes. Due to the strongly enhanced field,
aggregation of gold nanoparticles finds themselves plenty of
applications in bio-imaging. But limited by its small cross-section
associated with nanometer sized particle, it is a big challenge toemploy it in a single molecular detection. The field enhancement
results from the effect of plasmonic coupling between two
closely attached gold nanoparticle under the right excitation
condition. With the aim to apply the gold dimer probe to find themolecules in our recently established optical detection method,
we compared of the amplitude enhancement by the dimer
relative to a single particle. The amplitude distribution undera highly focused illumination objective was calculated, whose
results suggest that at the optimized excitation condition, thelocal field can be enhanced ~190 fold relative a single plasmonic
particle. In consequence, experimental detection was carried out.
Gold dimers were linked together by the hybridization of two
single chain DNAs. Dimer and single particle probes were mixed
together in one detection. Overwhelming contrast between thesetwo kinds of probes were clearly exhibited in the experimental
detection image. This method can provide a way to a highspecific detection in early diagnosis.

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139

Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-63, Session Post

10024-65, Session Post

Wavelength selection based on twodimensional correlation spectroscopy:
application to noninvasive hemoglobin
measurement by dynamic spectrum

In situ hyperspectral microscopy withacousto-optic tunable filter

Shengzhao Zhang, Zhe Li, Gang Li, Ling Lin, Tianjin Univ.
(China)Multispectral imaging systems are effective to acquire spatial andspectral features of biological tissues. There is a great interest in
developing multispectral imaging systems with the capability of
performing in situ tissue diagnosis without the need for sample
excision and processing. To satisfy the need of monitoring
dynamic phenomenon and observing multiple structures of thespecimen simultaneously, we develop a multispectral microscopic
imaging system with an acousto-optic tunable ﬁlter (AOTF).
AOTFs are solid state wavelength tunable optical ﬁlters andcan achieve spectral scanning at very high rates (milliseconds
timescale) without the possibility of error due to gear backslashor other mechanical problems. The system can achieve a spatial
resolution of 100 lines per mm with an effective aperture of 10mm. With the AOTF, the system can work within a wavelength
range from 450 nm to 720 nm in both reflection and fluorescencemodes. And this multispectral imaging system allows fastacquisition of spectral and spatial information of biologicaltissues in the wide field mode (2?2 mm, 10? objective lens).
Biomedical imaging experiments on the taste-goblet and the skintissue of a nude mouse are conducted to test the performance ofthe system. The results demonstrate that the system can provide
high spatial resolution multispectral images of biological tissues.

Lv Yanlu, Jing Bai, Jianwen Luo, Tsinghua Univ. School of
Medicine (China)

Dynamic spectrum (DS) method is one of the noninvasive
approaches to measure the concentration of components inhuman blood based on the application of photoplethysmogram(PPG). One of the targets of the DS method is to predict thehemoglobin concentration in human blood noninvasively. In
previous works, the usually used wavelength in the spectrum
is 600-1100 nm which is regarded as the analysis “window” inhuman tissues. Optimum wavelengths for measurements ofhemoglobin concentration have not been investigated yet. In
order to improve the precision and reliability of hemoglobin
measurements, a method for wavelength selection based on
two-dimension (2D) correlation spectroscopy has been studied
in this paper. By analyzing the 2D correlation spectroscopy
which is generated by the DS data from subject with different
blood hemoglobin concentrations, the wavelength bands which
are sensible to hemoglobin concentrations in DS can be found.
We developed calibration models between the DS data andhemoglobin concentration based on data from 57 subjects. The
correlation coefficient is 0.76 in the test set of the model using
the whole wavelength band (600-1100nm), while in the test setof the model using the selected wavelength band (850-950nm)
the correlation coefficient is 0.92. Results show the feasibility ofwavelength selection utilizing 2Dcorrelation spectroscopy.

10024-64, Session Post

Adaptive photoacoustic imaging quality
optimization with EMD and reconstruction
Chen Zhu, Jianbo Guo, Jie Yuan, Nanjing Univ. (China);
Guan Xu, Univ. of Michigan Medical School (UnitedStates); Xueding Wang, Univ. of Michigan (United States);Paul L Carson, University of Michigan (United States)
Biomedical photoacoustic (PA) signal is characterized withextremely low signal to noise ratio which will yield significant
artefacts in photoacoustic tomography (PAT) images. Since
PA signals acquired through ultrasound transducers are nonlinear and non-stationary, traditional data analysis methods
like Fourier analysis and wavelet analysis cannot give useful
information for further research. In this paper, we introduce anadaptive method to improve the quality of PAT images basedon empirical mode decomposition and reconstruction. PA
signals are adaptively decomposed into several intrinsic mode
functions (IMFs) after a time shifting pre-process. Since noise
is randomly distributed in different IMFs, depressing IMFs withmore noise while enhancing IMFs with less noise can effectively
enhance the quality of reconstructed PAT images. However,searching optimal parameters by means of brute force searchingalgorithms will cost too much time, which prevent this methodfrom clinical application. To find parameters within reasonable
time, Heuristic algorithms, which are designed for finding goodsolutions more efficiently, are adopted in our proposed method.
Two of the Heuristic algorithms, Simulated Annealing Algorithm,
a probabilistic method to yield global optimal solution, andArtificial Bee Colony Algorithm, an optimization method inspiredby the foraging behavior of bee swarm, are selected to search
optimal parameters of IMFs in this paper. The effectiveness of
our proposed method is proved both on simulated data and PA
signals from real biomedical tissue, which might be beneficial for
future clinical PA imaging de-noising.

140

SPIE Photonics Asia·

10024-66, Session Post

Spatially-variant regularization
algorithm based on cluster analysis forreconstruction of fluorescence molecular
tomography
Jiulou Zhang, Yanlu Lv, Jianwen Luo, Tsinghua Univ.
School of Medicine (China)
In fluorescence molecular tomography, the detector sensitivity isdegraded non-linearly with the increase of distance between the
fluorescent targets and detector, because of the absorbing andscattering characteristics of photons transport in heterogeneous
biological tissues. Thus, the relative-quantitation accuracy of
the reconstruction results is reduced when multiple fluorescenttargets with different depths and/or volumes appear randomly inthe tissues. A spatially variant regularization algorithm based oncluster analysis is proposed to improve the reconstruction quality.
The intermediate result is obtained by Tikhonov regularization
algorithm, in which different fluorescent targets and backgroundnoise can be roughly distinguished using the cluster analysis.
Then, small regularization parameter is set to deeper or smaller
fluorescent target and large parameters are allocated to othertargets and background noise. Numerical simulation and physicalphantom experiments are conducted to test the performance ofthe proposed algorithm. The relative-quantitation coefficients of
the reconstruction results are reduced from 0.3846 to 0.0265 and0.3353 to 0.0211 for numerical simulation and physical phantom
experiments, respectively. Furthermore, the corresponding signalto-noise ratios are increased from -8.11 to 20.60 and 1.40 to 2.34.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-67, Session Post

Influence of incident light offset on diffuse
reflectance measurement for curved
object: a Monte Carlo-based study
Chizhu Ding, Huazhong Agricultural Univ. (China)
Diffuse reflectance spectroscopy in the near-infrared (NIR)
spectral ranges is a widely used technique for non-destructive
inspection of biological tissues. The optical properties, such as
absorption and scattering coefficients, can be inversely deduced
from the measured quantities and then be used to speculate
on some related chemical and physical properties of the tissue.
Most studies consider biological tissues as homogeneous semiinfinite turbid media or infinitely-wide planar layered turbid
media. However, the biological tissues have various geometries,
and nearly all of them have curved surfaces. The position anddirection of the incident light relative to the tissue surface affectthe diffuse reflectance. In this work, we study the influence ofincident light offset on the measured diffuse reflectance signals
based on the Monte Carlo (MC) simulation. The MC method
are regarded as golden standard for light propagation in turbid
media and can be used without the limitations of complex
tissue geometries. A model for diffuse reflectance spectroscopy
measurement using optic fiber probe is built. The incident
light is assumed to be an infinitely narrow photon beam. The
tissue under detection is assumed to be spherical describedby its curvature radius. A series of Monte Carlo simulation
are carried out with varying incident positions. Simulation
results are analyzed and discussed to assess the influence on
the measurements for tissues with different curvature radii.
This study may aid in achieving more accurate and effective
measurement without extensive experiments.

10024-68, Session Post

Repetition doubling in a soliton selffrequency shift system for multiphoton
microscopy
Ke Wang, Jiexing He, Shenzhen Univ. (China)
Multiphoton microscopy (MPM) has benefitted tremendously
from the development of fiber-based laser technology, such as
soliton self-frequency shift (SSFS). SSFS enables femtosecond
laser pulse generation with broadband wavelength tunability
that spans hundreds of nanometers and excellent beam quality.
In MPM, signal level is linearly proportional to the repetition
rate of the laser system. As a result, below damage threshold,increasing the repetition rate of the laser system is an efficientmeans of achieving higher signal levels, which in turn could
reduce exposure time. Here we demonstrate a repetition doubling
technique that is well suited in doubling the repetition rate of
the SSFS system. Through polarization separation before andmultiplexing in a photonic-crystal (PC) rod, we could double therepetition rate of the optical solitons generated through SSFS.
The orthogonally polarized solitons have identical spectrum andpulse energy, which could find potential applications in boosting
signal levles in MPM.

10024-70, Session Post

Wavelength-swept fiber laser based on
acousto-optic tuning method
Minghui Chen, Fan Yunping, Zhang Hao, Tao Jianfeng,
Gang Zheng, Univ. of Shanghai for Science andTechnology (China)
In this study, we have demonstrated a wavelength-swept fiber
laser based on an acousto-optic tunable filter(AOTF) as aselective element and a semiconductor optical amplifier(SOA) as
a gain medium in an internal fiber ring cavity. The light derivingfrom one port of the SOA goes through an optical isolator, theAOTF, a fiber coupler and a polarized controller successively,
then it goes back to the other port of the SOA to form a ringcavity. The laser output is from another port of the fiber coupler.
The laser made by this method is mainly used for swept-source
optical coherence tomography(SS-OCT). The application of the
SOA provides a sufficiently broad range of tunability and canensure an increased axial resolution of SS-OCT. AOTF offeres awide tuning range, high switching speed and stable operation
against vibration for the non-mechanical structure. The proposed
wavelength-swept fiber laser ensures a high axial resolutionof tomographic images and has a stable laser ouput. We havediscussed the influence of the SOA injection current to thetuning range of the laser. In the SOA injection current of 280
mA, a continuous wavelength tuning range from 1295 to 1370 nm
centered at a wavelength of 1325 nm is obtained at the sweep
rate of 1.06 kHz. In addition, for quantitative characterizationof the wavelength-swept performance with a AOTF, we havetheoretically and experimentally analyzed the influence of the
fllowing controllable parameters: injection current, output powerand sweeping frequency.

10024-71, Session Post

10024-69, Session Post

Pigmented skin lesion detection using
random forest and wavelet-based texture
Ping Hu, Tie-Jun Yang, Guilin Univ. of Technology (China)
The incidence of cutaneous malignant melanoma, a disease ofworldwide distribution and is the deadliest form of skin cancer,
has been rapidly increasing over the last few decades. Because

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advanced cutaneous melanoma is still incurable, early detection
is an important step toward a reduction in mortality. Dermoscopy
photographs are commonly used in melanoma diagnosis andcan capture detailed features of a lesion. A great variability
exists in the visual appearance of pigmented skin lesions.
Therefore, in order to minimize the diagnostic errors that result
from the difficulty and subjectivity of visual interpretation, an
automatic detection approach is required. The objectives of thispaper were to propose a hybrid method using random forest
and Gabor wavelet transform to accurately differentiate whichpart belongs to lesion area while the other does not belong
to in a dermoscopy photograph, and analyze segmentation
accuracy. Gabor wavelet transform are the mathematical modelof visual cortical cells of mammalian brain and an image can be
decomposed into multiple scales and multiple orientations byusing it. The Gabor function has been recognized as a very useful
tool in texture analysis, due to its optimal localization properties
in both spatial and frequency domain. Texture features based on
Gabor wavelet transform are extracted in different scales andorientations. Then, a random forest classifier consisting of a setof decision trees is used for classification. Experiment results
indicate the following: (1) the proposed algorithm based on
random forest outperforms the state-of-the-art in pigmented skinlesions detection (2) and the inclusion of Gabor wavelet based
texture features can improve segmentation accuracy.

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Multiphoton microscopy for detecting
the depth of tumor infiltration in theesophageal squamous cell carcinoma
Jian Xu, Fujian Normal Univ. (China); Liwei Jiang, Chung
Yuan Christian Univ. (China); Deyong Kang, Xuejing Wu,
Meifang Xu, Fujian Medical Univ. (China); Shuangmu Zhuo,#PhotonicsAsia

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
Xiaoqin Zhu, Fujian Normal Univ. (China); Jiangbo Lin,
Fujian Medical Univ. (China); Jianxin Chen, Fujian Normal
Univ. (China)
Esophageal squamous cell carcinoma (ESCC) is one of themost common malignancies of the gastrointestinal cancers andcarries poorer prognosis than other gastrointestinal cancers.
Patients with early esophageal neoplasia limited to the mucosal
layer can be cured with endoscopic treatment, whereas patientwith more advanced carcinomas may achieve higher long-term
survival rates with appropriate treatment which is established byprimary tumor stage. However, the malignant degree of ESCC
in the esophageal wall is mainly determined by the depth oftumor infiltration. Our aim was to evaluate whether multiphoton
microscopy (MPM) can be used to detect the depth of tumor
infiltration in the esophageal wall. MPM is well-suited for realtime detecting morphologic and cellular changes in fresh tissues
since many endogenous fluorophores of fresh tissues are excitedthrough two-photon excited fluorescence (TPEF) and second
harmonic generation (SHG). In this work, spectral informationand morphological features of epithelial cells, collagen fibers
and muscular tissues were first studied. Then, the morphologicaldifferences between normal epithelial cells and tumor cells were
described. At last, tumor invasion of the mucosa, submucosa,
muscularis propria and adventitia were presented respectively.
These results show that MPM has the ability to detect the depthof tumor infiltration in the esophageal wall of ESCC. In the future,
MPM may be a promising imaging technique for preoperative
diagnosis of the depth of tumor infiltration in the esophageal wallof ESCC.

10024-72, Session Post

Identification of calcifications inintracranial neoplasms using two-photon
excitation fluorescence microscopy
Peihua Lin, Fujian Normal Univ. (China); Xingfu Wang,
Zanyi Wu, Fujian Medical Univ. (China); Na Fang,
Lianhuang Li, Fujian Normal Univ. (China); Dezhi Kang,
Fujian Medical Univ. (China); Jianxin Chen, Fujian Normal
Univ. (China)
Calcifications within brain tumors may be an indicator of a
relatively long survival because a long time is required forthe formation of calcium deposits, and may present a novel
biomarker associated with response and improved outcomeof therapy. In this paper, we describe the use of two-photon
excitation fluorescent (TPEF) microscopy combined second
harmonic generation (SHG) microscopy for high-resolution
imaging that can be applied in identification of intratumoral
calcification. Our results demonstrate that the calcification has
stronger TPEF signal than the area around it and the emission
spectra shows the difference between the two areas clearly.
The TPEF image of calcified region corresponds well with thecorresponding H&E stained image. In this work, we present
that the label-free imaging technique is able to distinguish thecalcified mass lesions in intracranial neoplasms reliably.

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10024-73, Session Post

Smart AQ4N-Cu(II)-DNA@GNPs nanocomplex for tumor-microenvironment
stimuli-responsive synergetic
photodynamic/aggregation-induced
photothermal therapyemotherapy ofhepatocellular carcinoma
Da Zhang, Ming Wu, Xiaolong Liu, Fujian Medical Univ.
(China)In this work, multi stimuli-responsive coordination nansystem
based on di-N-oxide of 1, 4-bis [2-(dimethyl aminoethyl-amino] 5,8-dihydroxyanthracene-9, 10-dione (AQ4N) prodrug and Cu(II)DNA(TLS11a aptamer)-gold nanoparticle were designed. Cu(II)DNA complexes are employed as a binders to guest AQ4N via
C-O and C=O bonds, formed a “host-metal-guest” architecture.
In aerobic cancer cells, the intracellular of GSH dissociate
chlorin e6 labelled-aptamer from GNPs and triggered an
activated fluorescence signal for real-time image and controlled
photodynamic therapy (PDT). AQ4N release was mainly
governed by acid-cleavage of the “guanine-Cu(II)” and “Cu(II)AQ4N”coordination bond, and this is accompanied by a releaseof Cu(II). The latter is immediately induced the electrostatic
aggregates of GNPs and shifted absorption peak to nearinfrared, which could be able to use as NIR-absorbing agentsfor photothermal ablation (PTA). Furthermore, the “on” state
PDT not only leads to serious cell damage but activate AQ4N
converted to cytotoxin (AQ4) in PDT-induced hypoxic microenvironment, achieving synergistic PDT / PTT-chemotherapy
under single laser irradiation in HCC. In summary, Tumormicroenvironment triggered multiple therapeutic stragtegies
may be open up new avenues for programmed and cost-effective
precision medicine in cancer therapy.

10024-74, Session Post

Identification of the boundary between
normal brain tissue and ischemia region
using two-photon excitation fluorescencemicroscopy
Huiping Du, Shu Wang, Fujian Normal Univ. (China);
Xingfu Wang, Fujian Medical Univ. (China); Xiaoqin Zhu,
Shuangmu Zhuo, Jianxin Chen, Fujian Normal Univ.
(China)Ischemic stroke is one of the common neurological diseases,
and it is becoming the leading causes of death and permanent
disability around the world. Early and accurate identification of
the potentially salvageable boundary region of ischemia brain
tissues may enable selection of the most appropriate candidates
for early stroke therapies. Our aim was to evaluate whether
two-photon excitation fluorescent (TPEF) microscopy can beused to identify the boundary between normal brain tissue andischemia region. TPEF microscopy has the ability to noninvasively
visualize the architectures of unstained biological tissues at thecellular level relied on intracellular intrinsic sources. In this work,
TPEF microscopy was used to image the microstructures ofnormal brain tissues, ischemia regions and the boundary region
between normal and ischemia brain tissues. The ischemia brain
tissues from Sprague–Dawley (SD) rats were subjected to 6
hours of middle cerebral artery occlusion (MCAO). Our study
demonstrates that TPEF microscopy has the ability to not only
reveal the morphological changes of the neurons but also identify
the boundary between normal brain tissue and ischemia region,
which correspond well to the hematoxylin and eosin (H&E)
stained images. With the development of miniaturized TPEF

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
microscope imaging devices, TPEF microscopy can be developed
into an effectively diagnostic and monitoring tool for cerebral
ischemia.

10024-75, Session Post

Research on hyperspectral imaging for
tobacco early diseases
Yan Zhang, Guiyang Univ. (China); Pinghe Wang, Univ. ofElectronic Science and Technology of China (China); Yan
Liu, Dan Wu, Guiyang Univ. (China)
There are many kinds of tobacco diseases which seriously
affect the quality and yield of tobacco. To identify diseases oftobacco in early stage is essential to the effective prevention
and treatment of them. Traditional methods such as visible
light image comparison and biochemical analysis are timeconsuming and arduous, which makes it difficult to realize thedetection and prevention of early-stage diseases of tobacco.
Meanwhile, the hyperspectral imaging technology combining
image and spectral information has the advantage to detect asample in a non-destructive and fast way, which offers promise
for its application in the non-destructive detection of earlystage diseases of tobacco. In the reasearch of this paper, thehyperspectral imaging technology was used to detect early-stage
diseases of tobacco. By inoculating tobacco mosaic virus on
Nicotiana tabacum and Nicotiana glutinosa, hyperspectral images
from different time points before and after the inoculation were
dynamically sampled. The images were preliminarily processed tofind the sensitive bands and suspected infected areas of earlystage diseases of tobacco, and then, by identifying the relevantcharacteristic parameters and combining the time-depending
images, a model of early-stage tobacco disease dection method
using hyperspectral imaging technology was established.

10024-77, Session Post

Quantification of collagen distributions in
rat hyaline and fibro cartilages based on
second harmonic generation imaging
Xiaoqin Zhu, Chenxi Liao, Fujian Normal Univ. (China);
Zhenyu Wang, Fujian Medical Univ. (China); Shuangmu
Zhuo, Fujian Normal Univ. (China); Wenge Liu, Fujian
Medical Univ. (China); Jianxin Chen, Fujian Normal Univ.
(China)Hyaline cartilage is a semitransparent tissue composed ofproteoglycan and thicker type II collagen fibers, while fibro
cartilage large bundles of type I collagen besides other territorial
matrix and chondrocytes. It is reported that the meniscus (fibro
cartilage) has a greater capacity to regenerate and close awound compared to articular cartilage (hyaline cartilage). And
fibro cartilage often replaces the type II collagen-rich hyaline
following trauma, leading to scar tissue that is composed ofrigid type I collagen. The visualization and quantification of
the collagen fibrillar meshwork is important for understanding
the role of fibril reorganization during the healing process andhow different types of cartilage contribute to wound closure. In
this study, second harmonic generation (SHG) microscope wasapplied to image the articular and meniscus cartilage, and Fourier
analysis were developed to quantify the collagen distribution.
High-resolution images were achieved based on the SHG signal
from collagen within fresh specimens, and detailed observationsof tissue morphology and microstructural distribution wereobtained without shrinkage or distortion. Fourier analysis of SHG
images was performed to confirm that collagen in fibrocartilage
showed significantly greater organization and directionality
compared to collagen in hyaline cartilage (p < 0.01). Our results

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Follow us on:show that each type of cartilage has different structural features,
which may significantly contribute to pathology when damaged.
Our findings demonstrate that SHG microscopy holds potential
as a clinically relevant diagnostic tool for imaging degenerative
tissues or assessing wound repair following cartilage injury.

10024-78, Session Post

Label-free imaging of rat spinal cords
based on multiphoton microscopy
Chenxi Liao, Fujian Normal Univ. (China); Zhenyu Wang,
Linquan Zhou, Fujian Medical Univ. (China); Xiaoqin Zhu,
Fujian Normal Univ. (China); Wenge Liu, Fujian Medical
Univ. (China); Jianxin Chen, Fujian Normal Univ. (China)
As an integral part of the central nervous system, the spinal cord
is a communication cable between the body and the brain. It
mainly contains neurons, glial cells, nerve fibers and fiber tracts.
The recent development of the optical imaging technique allows
high-resolution imaging of biological tissues with the great
potential for non-invasively looking inside the body. In this work,
we evaluate the imaging capacity of multiphoton microscopy(MPM) based on second harmonic generation (SHG) and twophoton excited fluorescence (TPEF) for the cells and extracellularmatrix in the spinal cord at molecular level. Rat spinal cord
tissues were sectioned and imaged by MPM to demonstrate that
MPM is able to show the microstructure including white matter,gray matter, ventral horns, dorsal horns, and axons based on the
distinct intrinsic sources in each region of spinal cord. In the highresolution and high-contrast MPM images, the cell profile can beclearly identified as dark shadows caused by nuclei and encircled
by cytoplasm. The nerve fibers in white matter region emitted
both SHG and TPEF signals. The multiphoton microscopic
imaging technique proves to be a fast and effective tool for labelfree imaging spinal cord tissues, based on endogenous signals
in biological tissue. It has the potential to extend this opticaltechnique to clinical study, where the rapid and damage-free
imaging is needed.

10024-79, Session Post

A method based on coffee-ring deposition
confocal Raman spectroscopy for analysisof melamine in milk
Zong Tan, Da Chen, Tianjin Univ. (China)
The safety of dairy products was a hot topic in the field of foodsafety and public health. In this work, melamine, which had
caused severe infant kidney damage for the illegal adding into
dairy products for its high nitrogen level, was chosen as thetarget analyte, and a method based on coffeeing effect micro
Raman spectroscopy for detection of melamine in milk wasdeveloped. In this method, the separation and enrichment effectof coffee-ring phenomenon was combined with the micro-region
analysis of micro Raman spectroscopy, in addition, assistedwith chemometric algorithmthe of discrete wavelet transform(DWT) to extract characteristic signal of target analyte fromcomplex and fluctuant noise and background interferences.
Consequently, a desired result was obtained that the LODof melamine in this method was as low as 1 ppm, which was
excellent with a sensitivity improvement of 103 - 104 times
better than conventional Raman method. Furthermore, thesample pretreatment was easy and convenient, and there wasalmost no chemical reagents consumption during the wholeprocess, as well as the detection process could proceeded inan easily available condition and the chosen substrates for theformation of coffee-ring were reusable. Thus, an economical, highefficient and envorinmental friendly method was established and#PhotonicsAsia

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Conference 10024:
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demonstrated a great potential application in safety inspection of
dairy products especially in less developed regions.

10024-80, Session Post

Monitoring the elasticity changes ofhela cells during mitosis by atomic force
microscopy
Ningcheng Jiang, Yuhua Wang, Fujian Normal Univ.
(China); Jinshu Zeng, Fujian Medical Univ. (China); Shusen
Xie, Hongqin Yang, Fujian Normal Univ. (China)
Cell mitosis plays a crucial role in cell life activity, which is oneof the important phases in cell division cycle. During the mitosis,
the cytoskeleton micro-structure of the cell changed and thebiomechanical properties of the cell may vary depending upon
different mitosis stages. In this study, the elasticity properties
of HeLa cells during mitosis were monitored by atomic force
microscopy. The distribution of actin filaments in different mitosis
stages of the cells was also observed by confocal imaging.
Our results show that the cell in anaphase is stiffer than that in
metaphase and in telophase. Furthermore, lots of actin filaments
gathered in cells center area in anaphase, which contributes tothe rigidity of the cell in this phase. Our findings demonstratethat the nano-biomechanics of the living cells could provide a
new index for characterizing cell physiological states.

10024-81, Session Post

Determination of acceptor-to-donor crosssection ratio for two-photon excitation inliving cells
Zexian Hou, Yuhua Wang, Liqin Zheng, Fujian Normal
Univ. (China); Tongsheng Chen, South China Normal Univ.
(China); Hongqin Yang, Shusen Xie, Fujian Normal Univ.
(China)The cross section is a significant parameter for fluorescence
protein and the determination of acceptor-to-donor cross section
ratio for two-photon excitation in living cells is the vital issue for
two-photon excitation FRET quantification. In this study, Helacells were labeled with FPs that acceptor-to-donor concentration
ratio is 1 to 1 and acceptor-to-donor cross section ratio ranged
from 700nm to 950nm was obtained by emission spectral
unmixing with independent excitation crosstalk correction. The
results show that acceptor-to-donor cross section ratio declines
with the excitation wavelength from 700nm to 790nm and thenincreases inversely from 790nm to 950nm, which is consistent
with 2-channel FRET quantification method. This method canquickly determine the cross section without any additionalreferences and could provide a powerful and convenient tool formeasuring acceptor-to-donor cross section ratio by two-photon
excitation in living cells.

10024-82, Session Post

Detection of mast cell secretion by using
surface-enhanced Raman scattering
Juan Li, Ren Li, Liqin Zheng, Yuhua Wang, Shusen Xie,
Juqiang Lin, Fujian Normal Univ. (China)
Acupuncture can cause a remarkable increase in degranulationof the mast cells, which has attracted the interest of researchers
since the 1980s. Surface-enhanced Raman scattering (SERS)
could obtain biochemical information with high sensitivity and

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specificity. In this study, SERS was used to detect the degree ofdegranulation of mast cells according to different incubate time.
Mast cells was incubated with culture medium for 0 h, 12 h and 24
h, then centrifuge the culture medium, decant the supernatant,and discard the mast cell. SERS was performed to obtain thebiochemical fingerprinting signatures of the centrifuged medium.
The spectra data are then analyzed by spectral peaks attribution
and the principal component analysis (PCA). The measured
Raman spectra of the two groups were separated well by PCA.
It indicated that mast cells had secreted some substances into
cultured medium though degranulation did not happen.

10024-83, Session Post

Polymer dots with broadband opticalabsorption (500 nm - 700 nm) and highefficiency photoacoustic conversion for invivo multispectral photoacoustic imaging
Jian Zhang, zhen Yuan, Univ. of Macau (Macao, China)
Multi-spectral photoacoustic (MSPA) imaging can extract
quantitative information of interesting component frommorphological photoacoustic image of targets. A probe with an
optimal optical absorption can be detected by MSPA imaging
with higher sensitivity and specificity. Here we developed aNano polymers dots (P-dots) for MSPA imaging that has ahigh photoacoustic conversion efficiency in a broad opticalabsorbing band (500 nm - 700 nm). Both ex vivo photoacoustic
imaging of phantom and in vivo photoacoustic imaging
experiment demonstrated P-dots has better performance thangold nanoparticles and gold nanorods. In vivo MSPA imaging
experiment was successfully performed in mouse model. The
relative concentration map of P-dots was exactly obtained fromthe background of tissues, which demonstrated the potential useof P-dots in the bio-imaging field based on MSPA imaging.

10024-84, Session Post

Effect of 17[beta]-estradiol on theelasticity of MCF-7 cells by atomic force
microscopy
Yuhua Wang, Liqin Zheng, Hongqin Yang, Shusen Xie,
Fujian Normal Univ. (China)
Estrogen plays an important role in the development andprogression of breast cancer, and it promotes proliferation,
invasion and metastasis of the breast cancer cells. In this paper,
we investigated the effect of estrogen on the elasticity of breast
cancer cells. 17?-estradiol, one of the most active estrogen in thehuman body was applied to MCF-7 living cells and the elasticityof the cells were measured by atomic force microscopy. The force
spectroscopy was performed on the center of the cell and the
Hertz model was used to calculate the elasticity. Furthermore,
the confocal fluorescence imaging was taken to observe theeffect of 17?-estradiol on the actin distribution in the cells. The
results show that the elasticity of the cells is 218.1±54.6 Pa. Afterthe addition of 17?-estradiol, the value declines to 181.7±42.7 Pa.
The elasticity of the cells decreases rapidly, which indicates thatthe cells appear softer responding to 17?-estradiol. In addition,from the confocal imaging, it can be observed that the actin
appears less in the center of the cell and assembles toward thecell edge for 17?-estradiol’s treatment, which may contribute to
the alteration of the cell elasticity. Our findings may deepen our
understanding on the rapid effect of 17?-estradiol to MCF-7 cells.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-85, Session Post

Numerical simulation and analysis of
accurate blood oxygenation measurement
by using optical resolution photoacoustic
microscopy
Tianhao Yu, Qian Li, Lin Li, Xinyu Chai, Chuanqing Zhou,
Shanghai Jiao Tong Univ. (China)
Accuracy of photoacoustic signal is the crux on measurementof blood oxygen saturation in photoacoustic imaging, which is
influenced by factors such as out-of-focus laser, edge of great
vessels, saturation nonlinear effect of optical absorption in
biological tissues. We apply Monte Carlo modeling to stimulateenergy deposition and predict acoustic signals reaching a given
focused surface detector. The stimulation models blood vessels
positioned under particular depth of dermis with different
optical absorption coefficients and focus positions. The spatial
distribution of energy deposition is calculated and imaged,
then turned to stress wave based on the velocity potential. The
results show that acoustic signal attenuation will occur on edgeof blood vessel, which will obviously effect calculation of oxygen
saturation in universal voxel-based method. As for out-of-focus
factor, results show that for great blood vessel, excursion of
100 microns on z direction can bring about error of 5%, which
may influence accuracy of quantitative photoacoustic imaging
in particular with uneven tissue surface. In follow-up phantom
tests, a transparent tube and diluted double-ink mixtures areused to simulate circumstance of blood vessel. We adjust B-scansignals on edge of tube based on specific A-line depth, in which
inverse calculation of ink ratio is more accurate. We also apply
the compensation on photoacoustic signals of in vivo cerebral
blood vessels, in which signals from edge of vessels on different
depths are corrected according to their particular positions.
And this process obviously improve the accuracy of oxygen
saturation calculation. As for optical absorption, photoacoustic
signal amplitude is found to be linearly proportional to the given
coefficient of blood vessel and ink on both stimulation andphantom tests, which can be regarded negligible in OR-PAM
system.

10024-86, Session Post

In vivo noninvasive measurement ofpreprandial and postprandial blood
glucose using optical coherence
tomography
Ying Zhang, Xiyang Zhang, Zhifang Li, Hui Li, Fujian
Normal Univ. (China)
Blood glucose concentration measurement is essential for the
diagnosis and treatment of diabetes. However, conventional
glucose measurement methods are invasive and not suitable forreal-time monitoring. This study demonstrated a noninvasive
blood glucose measurement method using optical coherence
tomography to image human lip in vivo. Optical coherence
tomography (OCT) is a noninvasive and depth-resolved
technique capable of acquiring tissue structure images in realtime. Human lip has very thin skin and is full of blood vessels,
which is appropriate for noninvasive glucose measurement. To
verify the feasibility of OCT for glucose concentration monitoring,
two groups of OCT imaging data were obtained from human lips
of normal people. In one group, OCT images of lip were acquired
from people on an empty stomach. In the other group, the samesites of lip were observed by OCT 2 hours after breakfast. Evident
differences were found from two groups of OCT images that
correspond to preprandial glucose and 2-hours postprandial
glucose, respectively. The relationship between OCT image

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and blood glucose concentration was investigated. The result
indicates that OCT possesses considerable prospects in terms of
noninvasive blood glucose measurement.

10024-87, Session Post

Measuring blood oxygenation of pulsatilearteries using photoacoustic microscopy
Qian Li, Tianhao Yu, Lin Li, Xinyu Chai, Chuanqing Zhou,
Shanghai Jiao Tong Univ. (China)
Heart pumps blood through the blood vessels to provide bodywith oxygen and nutrients. As the result, the blood flow, volume
and oxygenation in arteries has a pulsatile nature. Measuring
these pulsatile parameters enables more precise monitoring ofoxygen metabolic rate and is thus valuable for researches andclinical applications. Photoacoustic microscopy (PAM) is a provenlabel-free method for in vivo measuring blood oxygenation at
single blood vessel level. However, studies using PAM to observe
the pulsatile nature of arteries is lacking. In this paper, we use
optical-resolution PAM (OR-PAM) technology to study the blood
oxygenation dynamics of pulsatile arteries. First, the ability of
our OR-PAM system to accurately reflect the change of opticalabsorption in imaged objects is demonstrated in a phantom
study. Then the system is used to image exposed cortical
blood vessels of cat. The pulsatile nature of blood volume andoxygenation in arteries is clearly reflected in photoacoustic (PA)signals, whereas it’s not observable in veins. By using multiwavelength laser light, the blood oxygenation of pulsatile arteries
can be measured, based on the spectroscopic method.

10024-88, Session Post

Self-assembled dye-doped polymer
microspheres as whispering gallery modelasersXiaogang Chen, Fujian Normal Univ. (China); Hongyi Sun,
Fudan Univ. (China); Hongqin Yang, Fujian Normal Univ.
(China); Xiang Wu, Fudan Univ. (China); Shusen Xie, Fujian
Normal Univ. (China)
Microlasers based on high-Q whispering-gallery-mode (WGM)
resonances are promising low-threshold laser sources for biosensing and imaging applications. In this talk, we demonstrate
a cost effective approach to obtain size-controllable polymer
microspheres, which can be served as good WGM microcavities.
By injecting SU-8 solution into low-refractive-index UV polymer,
self-assembled spherical droplet with smooth surface can becreated inside the elastic medium and then solidified by UV
exposure. The size of the microspheres can be tuned from several
to hundreds of microns. WGM Lasing has been achieved by
optically pumping the dye-doped microspheres with ns lasers.
Experimental results show that the microsphere lasers have highquality factors and low lasing thresholds. The self-assembled
dye-doped polymer microspheres would provide an excellent
platform for the micro-laser sources in on-chip biosensing andimaging systems.

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10024-89, Session Post

10024-91, Session Post

A method to improve the measurement
stability of scattering coefficients in
lip and tongue with optical coherence
tomography

Quantitative optical biomarkers of lungcancer based intrinsic two-photon excited
fluorescence signal
Jingwen Li, Zhenlin Zhan, Hongxin Lin, Xiaoqin Zhu,
Jianxin Chen, Shuangmu Zhuo, Fujian Normal Univ.
(China)Xiyang Zhang, Ying Zhang, Zhifang Li, Hui Li, Fujian
Normal Univ. (China)
Optical coherence tomography (OCT) is a non-invasive imaging
technique that provides real-time two- and three-dimensional
images of scattering tissues with micrometer resolution.
Scattering coefficient is estimated based on the slope of OCT
dependent of depth. However, stability of the OCT signal slope
is dependent on tissue heterogeneity . Our work is to provide
a method of combining post-processing Fourier filtration with
automatic identification of fitting range to reduce the effectof tissue heterogeneity on scattering coefficient, and used fornoninvasive monitoring of glucose concentration in lip andtongue respectively. Axial and lateral resolutions of OCT are 20µm and 15 µm respectively. OCT images were obtained fromlip and tongue before and after breakfast respectively. Results
demonstrate that the method improve the stability and theprecision of measurement of scattering coefficient of lip andtongue. There are obviously different in scattering coefficientof tissue between preprandial glucose and 2-hours postprandial
glucose. These pilot studies show that OCT scattering coefficient
extraction of lip and tongue may be considered as a significant
diagnostic marker. OCT has potential to monitor glucose-inducedchanges in lip and tongue in vivo.

10024-90, Session Post

The optimum measurement precisionevaluation for blood components usingnear-infrared spectra on 1000-2500 nm
Ziyang Zhang, Di Sun, TongShuai Han, Chao Guo, Jin Liu,
Tianjin Univ. (China)
In the non-invasive blood components measurement usingnear infrared spectroscopy, the useful signals caused by theconcentration variation in the interested components, such as
glucose, hemoglobin, albumin etc., are relative weak. Then thesignals may be greatly disturbed by a lot of noises in various
ways. We improved the signals by using the optimum pathlength for the used wavelength to get a maximum variationof transmitted light intensity when the concentration of acomponent varies. And after the path-length optimization forevery wavelength in 1000-2500 nm, we present the detection
limits for the components, including glucose, hemoglobin
and albumin, when measuring them in a tissue phantom. The
evaluated detection limits could be the best reachable precisionlevel since it assumed the measurement uses a high signal-tonoise ratio (SNR) signal and the optimum path-length. From theresults, available wavelengths in 1000-2500 nm for the threecomponent measurements can be screened by comparing theirdetection limit values with their measurement limit requirements.
For other blood components measurement, the evaluation on
their detection limits could also be designed using the method
proposed in this paper. Moreover, we use an equation to estimate
the absorbance at the optimum path-length for every wavelengthin 1000-2500 nm caused by the three components. It could be aneasy way to realize the evaluation because adjusting the sample
cell’s size to the precise path-length value for every wavelengthis not necessary. This equation could also be referred to otherblood components measurement using the optimum path-lengthfor every used wavelength.

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Alterations in the elastic fibers have been implicated in lungcancer. However, the label-free, microscopic imaging of elastic
fibers in situ remains a major challenge. Here, we present theuse of intrinsic two-photon excited fluorescence (TPEF) signal
as a novel means for quantification of the elastic fibers in intact
fresh human lung tissues. We obtained the TPEF images ofelastic fibers from ex vivo the human lung tissues. We found thatthree features, including the elastic fibers area, the elastic fibers
orientation, the elastic fibers structure, provide the quantitative
identification of lung cancer and the direct visual cues for cancer
versus non-cancer areas. We described that the combination of
all three features by using a support vector machine classification
algorithm can provide a more accurate prediction than eachfeature alone in lung diagnosis. These results suggest that the
TPEF signal can be used as the label-free optical biomarkers for
rapid clinical lung diagnosis and instant image-guided surgery.

10024-92, Session Post

Performance evaluation of akinetic swept
sources for both intensity and phasebased OCT angiography
Mengyang Liu, Zhe Chen, Medizinische Univ. Wien
(Austria); Laurin Ginner, Medical University of Vienna(Austria); Michael P. Minneman, Erich E. Hoover, Jason R.
Ensher, Insight Photonic Solutions, Inc. (United States);
Rainer Andreas Leitgeb, Wolfgang Drexler, Medizinische
Univ. Wien (Austria)
As the most successful functional extension of optical coherence
tomography (OCT) nowadays, OCT based angiography (OCTA)
gradually becomes a standard add-on feature for OCT systems.
It is easily implementable in most spectral domain systems andcan yield clinically relevant volumes at the same time whenmorphological volumes are acquired. For OCTA, both intensity
based and phase based algorithms are developed to visualize
vasculature, but phase based OCTA normally does not use swept
source OCT (SS-OCT) due to the consideration of phase stability
issues and trigger jitter problems in most swept sources. In ourwork, we present an OCTA system employing an akinetic swept
source which provides high wavelength stability with a phaserepeatability <2 mrad (measured in terms of standard deviation).
To fully evaluate the akinetic swept sources’ potential for OCTA,
we tested the system using two wavelength ranges, one at 1340
nm with 30 nm bandwidth and the other at 1550 nm with 40 nm
bandwidth. Another akinetic source with 100 nm bandwidth wastested to compare bandwidth’s effects on OCTA. It is proved byour results that this akinetic source enables SS-OCTA without
the need for hardware phase stability control or excessive
post-processing. The impact of higher phase stability of thesources used on the number of tomograms needed for motion
contrast compensation is also discussed. We also compared
the differences of intensity based and phase based OCTA using
akinetic swept sources. In in vivo applications, we demonstrated
that phase based OCTA has better resolvability for humanvasculature in deeper depth range.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-93, Session Post

Effects of large blood vessel on
temperature distribution based on
photothermal coupling interaction model
Zhifang Li, Fujian Normal Univ. (China); Xiyang Zhang,
Zuoran Li, Fujian Normal Univ (China); Hui Li, Fujian
Normal Univ. (China)
In the study, the distribution of light and temperature in
biological tissue over time was studied in some cases of opticalproperties dynamically-changed with temperature using thefinite element method to couple the physical field of biologicaltissue optical transmission with the physical field of biologicaltissue heat transfer. The results demonstrated that the piecewise
dependence of optical properties on temperature for dynamic
photothermal coupling interaction model is consistent with theexperimental results. It could be potential applications for laserintersititial thermotheraphy and laser immunotherapy.

To enhance drug delivery performance of popular drug eluting
balloon(DEB) against re-stenosis after angioplasty, we have an
idea of adjacent use of our unique laser driven thermal balloon ofwhich realize short term and uniform temperature
to modify delivery characteristics. We have already reported
an enhancement effect using this idea, however, detailed
characteristics is unknown. Therefore, we studied balloon
dilatation on the heating drug delivery performance in terms ofvascular circumferential tension using porcine carotid artery wall
ex vivo.
The extracted carotid wall was used and circumferential tensionof 0-30 mN/mm^2 was added.
Heating drug delivery was performed on this carotid wall withthe heated solution of hydrophobic fluorescent Rhodamine B
with 3 ?g/ml in concentration and 60, 70, and 37?. We measured
a defined drug delivery quantity as well as delivery depth by amicroscopic fluorescence measurement on the cross section of
the drug delivered vessel.
In the case of 60, 70?, we found the drug penetration increaseagainst 37? case.
We predict that the collagen thermal denaturation of the vessel
wall may play important role to this penetration.

10024-94, Session Post

The effect of hematoxylin-andeosin staining on the result ofmultiphoton microscopy imaging
Yaping Zeng, Jian Xu, Fujian Normal Univ. (China); Deyong
Kang, Jiangbo Lin, Fujian Medical Univ. (China); Jianxin
Chen, Fujian Normal Univ. (China)
Multiphoton microscopy (MPM) based on two-photon excited
fluorescence (TPEF) and second harmonic generation (SHG)
imaging, has become a powerful, important tool for tissue
imaging at the molecular level. Recently, MPM is also used toimage hematoxylin and eosin (H&E)-stained sections in cancer
diagnostics. However, several studies have showed that theresults of H&E-stained sections are very different from unstained
tissue sections. The unstained tissue could reveal TPEF and
SHG image. But the H&E-stained tissue can only reveal a TPEF
image. Our aim was to evaluate how the dyes affect the resultsof imaging by using MPM. In this paper, MPM was used to image
histological sections of esophageal invasive carcinoma tissues
stained with H, E, and H&E. For comparison, the unstained
esophageal invasive carcinoma tissues were also investigated.
To elucidate the origins of multiphoton signals in histologicalsections, the emission spectroscopic of H, E, H&E, and unstained
tissue were obtained. Our results showed that the tissue stainedwith H, E, H&E could show and enhanced the TPEF signal, even
low power laser could excite it. But only the H stained andunstained tissue reveal the TPEF and SHG signals. The absent
SHG of collagen showed the H&E staining procedure destroyed
the noncentrosymmetric molecular structure of collagen. Besides,
there is leakage of TPEF signal into the SHG channel. Thus, in the
H&E-stained tissue where the SHG signal hardly be observed. In
this work, we reveal the effect of H&E stained on multiphoton
signals. These findings will be useful for choosing suitable
staining method so to improve the quality of cancer imaging anddiagnosis in the future.

10024-95, Session Post

The novel drug delivery to vascular wallusing laser driven thermal balloon: basic
study ex vivo

In the case of 37?, we found the intima surface drugconcentration with 7 mN/mm^2 at 37? was increased as 10-30
times as other tension values. We found surface grooves in thiscase using an electron micrography. Therefore, we think thatthe drug delivery enhancement might be related to the groove
formations of the vessel wall.

10024-96, Session Post

Optimization on source detector distancefor the glucose sensing in a tissue
phantom using near-infrared diffuse
spectraChao Guo, Ziyang Zhang, Tongshuai Han, Di Sun, Jin Liu,
Tianjin Univ. (China)
In the non-invasive blood glucose concentration (BGC) sensing,the measurement based on near infrared spectroscopy has
been a promising technology since it had acquired dozens ofsatisfactory results in short-term glucose monitoring tests.
However, it’s still necessary to improve the measurement
precision because it has challenges of the reduced precision ina long-term test when a lot of variables in the test would exist.
Considering the requirement of multivariable analysis, the signalsof diffuse reflectance spectra should include enough absorption
information from glucose. However, the sensitivity of diffuse
light intensity to the absorption variation at different source
detector separations (SDSs) could be different. We present ananalysis method using Monte-Carlo (MC) simulation and the
diffuse equation for reasonably selecting proper SDS to geta satisfactory glucose measurement precision when there are
multivariable disturbances. In the case of measuring glucose in atissue phantom using the waveband of 1000-1340nm, we show
the SDS optimization result by using this analysis method. The
experiment was designed to measure the diffuse reflectancespectra at 0.1-3 mm with the step of 0.1 mm, and the phantom
solutions with different glucose concentrations and hemoglobin
concentrations are tested. The glucose prediction precision
was evaluated using the root mean squared error of prediction(RMSEP) for the all SDSs of 0.1-3mm, and the SDSs with the lower
RMSEP were selected for use. Moreover, the selected SDSs in theexperiment shows a similar conclusion from the MC simulation.
This work could be referenced to the in vivo BGC measurement.

Kao Suganuma, Rie Homma, Natsumi Shimazaki, Emiyu
Ogawa, Tsunenori Arai, Keio Univ. (Japan)

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147

Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-97, Session Post

phase volume decreased severely with time when erythrocytes
were in Pb ion solution. The quantitative measurement can
provide reference for erythrocyte testing and study, additionally,it also proves that quantitative interferometric microscopy is aneffective tool in cellular observations and measurements.

Assessment of spatial information for
hyperspectral imaging of lesion
Xue Yang, Gang Li, Ling Lin, Tianjin Univ. (China)
Multiple diseases such as breast tumor poses a great threat towomen’s health and life, while the traditional detection method
is complex, costly and unsuitable for frequently self-examination,
therefore, an inexpensive, convenient and efficient method fortumor self-inspection is needed urgently, and lesion localization
is an important step. This paper proposes an self-examination
method for positioning of a lesion.
The method adopts transillumination to acquire the hyperspectral
images and to assess the spatial information of lesion. Firstly,
multi-wavelength sources are modulated with frequency
division, which advantageous to separate images of different
wavelength, meanwhile, the source serves as fill light to eachother to improve the sensitivity in the low-light-level imaging.
Secondly, the signal-to-noise ratio of transmitted images after
demodulation are improved by frame accumulation technology.
Next, gray distributions of transmitted images are analyzed
through gray-level ratio images. The gray-level ratio images
is constituted by the ratio of actual transmitted images andfitting transmitted images of tissue without lesion, which is torule out individual differences. Due to scattering effect, there
will be transition zones between tissue and lesion, and the zonechanges with wavelength change, which will help to identify the
structure details of lesion. Finally, image segmentation is adopted
to extract the lesion and the transition zones, and the spatial
features of lesion are confirmed according to the transition zones
and the differences in the ratio images. Experiment using flatshaped tissue as an example shows that the proposed method
can extract the space information of lesion.

10024-98, Session Post

Phase measurements and analysis onerythrocytes affected by lithium and leadions with quantitative interferometricmicroscopy
Qi Wei, Jiangnan Univ. (China); Keding Yan, Xi’an
Technological Univ. (China); Xiaojun Song, Liang Xue,
Shanghai Univ. of Electric Power (China); Cheng Liu,
Shouyu Wang, Jiangnan Univ. (China)
Compared to traditional intensity and fluorescent based imaging,phase imaging techniques are able to obtain high contrast
sample information often without labeling, thus they can be
widely applied for live cell observations and measurements.
Among these phase imaging techniques, interference based
methods not only can retrieve quantitative phase distributions
compared to those qualitative approaches including phase
contrast and differential interference contrast, but also owns
real time capability and compact system, thus it acts asimportant tool in biological and medical imaging. Taking theadvantages of the quantitative interferometric microscopy, inthis paper, the morphology of erythrocytes affected by metal
ions are measured and analyzed in details. Quantitative phase
distributions of live erythrocytes cultured in 0.9% NaCl solution
with lithium carbonate at Li ion density of 0.1 mM and 0.9% NaClsolution with lead nitrate at Pb ion density of 0.1 ?M, respectively,
were obtained via interferograms capturing by quantitativeinterferometric microscopy and phase retrieval according tofast Fourier transform based algorithm. According to multiple
sample measuring and statistical analysis, it indicates that whenerythrocytes were affected by Li ion, phase volume decreased
as phase distributions of erythrocytes reduced, while cellulararea did not change obviously. However, both cellular area and148

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10024-99, Session Post

Endoscopic optical coherence tomographyusing compressive sensing
Jie Wang, Yang Hu, Jigang Wu, Shanghai Jiao Tong Univ.
(China)Optical Coherence Tomography (OCT) is a widely usedbiomedical imaging modality in clinical diagnosis because of
its advantage of high resolution and being non-invasive. And
endoscopic OCT aims to examine the interior of hollow organs
and structures such as respiratory tract and blood vessels.
Conventionally OCT images are reconstructed by uniform
sampling in both axial and transverse direction of the image. And
the sampling distance must satisfy the Nyquist sampling criteria
to match the image resolution. To shorten the scanning time andreduce the acquisition data, we propose to sparsely sample theaxial scans and use compressive sensing (CS) reconstruction inendoscopic OCT imaging. Since being proposed in 2006, CS havebeen proved to be efficient to reconstruct the full image withrandom part of original information under specific conditions.
Similarly, we can reconstruct the full endoscopic OCT image withrandomly chosen axial scans that are much less than conventional
Nyquist criteria requirement. We have designed and made a
prototype side-imaging endoscopic OCT imaging system todemonstrate our idea. Our endoscopic OCT probe can achieve
circumferential scanning by rotating a reflecting micro-prismfor 360 degrees. Unlike compressive sensing reconstruction insparsely sampled rectilinear images, the sampling distances in
the circumferential images are different for different imaging
depths and require additional considerations. And we study
the ratio of sparse sampling numerically and experimentallythat are required to reconstruct acceptable OCT images. We
have demonstrate that the OCT image acquisition time can besignificantly reduced because of much less acquired data.

10024-100, Session Post

Temperature insensitive prediction of
glucose concentration in turbid medium
using multivariable calibration based on
external parameter orthogonalization
TongShuai Han, Ziyang Zhang, Chao Guo, Di Sun, Jin Liu,
Tianjin Univ. (China)
The measurement accuracy of non-invasive blood glucose
concentration (BGC) sensing with near-infrared spectroscopy
is easily affected by the temperature variation in tissue
because it would induce an unacceptable spectrum variationand the consequent prediction deviation. We use a
multivariable correction method based on external parameterorthogonalization (EPO) to calibrate the spectral data recorded
at different temperature values to reduce the spectral variation.
The tested medium is a kind of tissue phantom, the Intralipid
aqueous solution. The calibration uses a projection matrix to
get the orthogonal spectral space to the variable of externalparameter, i.e. temperature, and then the useful spectral
information relative to glucose concentration has been reserved.
Even more, training the projection matrix can be separated tobuilding the calibration matrix for the prediction of glucose
concentration as it only uses the typical samples’ data withtemperature variation. The method presents a lower complexity

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
than modeling a robust prediction matrix, which can be built
from comprehensive spectral data involved the all variables bothof BGC and temperature. In our test, the calibrated spectra withthe same glucose concentration but different temperature values
show a significantly improved repeatability. And then the glucose
concentration prediction results show a lower root mean squared
error of prediction (RMSEP) than that using the robust calibration
model, which has considered the two variables. We also discuss
the selection of the used typical samples to get a better
calibration. This research may be referenced to the temperature
calibration for in vivo BGC sensing.

10024-101, Session Post

Determination of the reference positionin the near-infrared non-invasive blood
glucose measurement in vivo
Guang Han, Jin Liu, Rong Liu, Kexin Xu, Tianjin Univ.
(China)Position-based reference measurement method is taken as oneof the most promising method in non-invasive measurement ofblood glucose based on spectroscopic methodology. Selecting anappropriate source-detector separation as the reference position
is important for deducting the influence of background change
and reducing the loss of useful signals. Our group proposed a
special source-detector separation named floating-reference
position where the signal contains only background change,that is to say, the signal at this source-detector separationis uncorrelated with glucose concentration. The existence offloating-reference position has been verified in a three layer
skin by Monte Carlo simulation and in the in vitro experiment.
But it is difficult to verify the existence of floating-reference
position on the human body because the interference is more
complex during in vivo experiment. Aiming at this situation, thispaper studies the determination of the best reference position
on human body by collecting signals at several source-detector
separations on the palm and measuring the true blood glucose
levels during oral glucose tolerance test (OGTT) experimentsof 5 subjects. Partial least square (PLS) calibration model isestablished between the signals at every source-detector
separation and its corresponding blood glucose levels. The resultsshows that the correlation coefficient around 2mm is lowest andit can be used as reference for background correction. The signalof this special position is important for improving the accuracy ofnear-infrared non-invasive blood glucose measurement.

10024-102, Session Post

Rotary-scanning optical resolution
photoacoustic microscopy
Weizhi Qi, Lei Xi, Univ. of Electronic Science andTechnology of China (China)
Optical resolution photoacoustic microscopy (ORPAM), one of
the fastest developing photoacoustic imaging modalities, owns
comparable spatial resolution but deeper penetration depth
compared with pure optical microscopic techniques such as
fluorescence confocal microscopy, two-photon microscopy andoptical coherence microscopy. In this letter, we developed a new
ORPAM system without raster scanning of imaging interfaces
or objects. We utilized a two-dimensional (2D) galvanometerscanner together with a scanning lens to realize 2D scanningof the laser beam. A 10 MHz cylindrically focused ultrasoundtransducer was mounted on a motorized rotation stage tosynchronized move with the laser beam. To minimize the loss insignal to noise ratio (SNR), the position of acoustic focus was
optimized to achieve confocal with optical focus. Carbon fibers
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evaluate the lateral resolution of the system. We have achieved
resolutions of 10 ?m in lateral and 70 ?m in axial. Additionally,
we successfully accomplished in vivo imaging of vasculature
network inside mouse ears by using this system. This study
suggests that this new ORPAM system has the potential to be
used in applications where raster scanning of imaging interfaces
or objects is not suitable.

10024-103, Session Post

Fast acquisition of Golgi-stained neuronalmorphology and distribution with
anatomical annotation at single-cellresolution in whole brain
Xiao Chen, Xiaoyu Zhang, Qiuyuan Zhong, Jing Yuan,
Hui Gong, Qingming Luo, Huazhong Univ. of Science andTechnology (China)
Precisely annotating and accurately reconstructing dendritic
morphology of Golgi-stained neurons are prerequisite to cell
type study. However there is no research tool to orientate
Golgi-stained neurons at single cell resolution due to the lackof anatomic reference in existing whole-brain imaging datasets.
Here, we develop a dual-mode micro-optical sectioning
tomography (dMOST) for dissecting and locating brain-wide
Golgi-stained neurons with cytoarchitectonic landmarks atsingle-cell resolution. We introduce a whole-brain real-time
counterstain protocol for staining cytoarchitectonic landmarks
simultaneously during the imaging process. The method
employs a three-working window dichroic mirror to achieve
simultaneous detection of both reflective (for Golgi staining)
and fluorescent (for cytoarchitecture staining) signals. Structural
illumination helps the method to improve imaging throughput
and accelerate whole-brain imaging at single-neuron resolution.
By this system, we acquire a full-volume, dual-color mousebrain datasets of Golgi-stained neurons with single-cell locationreference at a voxel size of 0.32 ? 0.32 ? 1.0 ?m in 88 hours. For
this dataset, we also define different brain regions according to
the cytoarchitecture images, and then analyze the cell densities
of Golgi-stained neurons in different brain regions. These results
show that dMOST can be used as an essential tool for brainwidely anatomizing dendritic morphology at precise anatomicalannotation.

10024-104, Session Post

Unwrapping and aberration compensation
free-phase retrieval method forquantitative interferometric microscopy
Keding Yan, Xiaoning Yu, Xi’an Univ. of Technology(China); Xiaojun Song, Liang Xue, Shanghai Univ. ofElectric Power (China); Shouyu Wang, Jiangnan Univ.
(China)As quantitative interferometric microscopy can provide phase
distributions of biological samples, it is becoming important
detecting tool in cellular observations and measurements in bothbiological and medical fields. However, traditional quantitativeinterferometric microscopy suffers from the complex phaseunwrapping procedure, which needs long time consuming andheavy calculation load and limits its applications in dynamic andhigh speed measurements. Though several methods as dualwavelength algorithm are proposed to accelerate the phaseunwrapping speed, they often need more additional devices
and complicated systems. In order to increase the calculation
efficiency of phase retrieval as well as simplify its procedures,
here, a high speed moire based phase retrieval method is#PhotonicsAsia

149

Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-107, Session Post

proposed which is capable of recovering quantitative phase
distributions in fringe analysis without phase unwrapping or
aberration compensation. Both numerical simulations andexperiments are provided proving that the method not only
can retrieve the high-accurate quantitative phase distributionsof cells, but also raise the calculation efficiency for nearly 100
times compared to traditional phase retrieval since both phaseunwrapping and aberration compensation are not necessary
in the phase retrieval process. It is believed that the proposed
method would be useful in real time phase observations andmeasurements.

An experimental research on highlysensitive pharmacokinetic diffuse
fluorescence tomography of CT scanningmode
Yanqi Zhang, Xin Wang, Limin Zhang, Huijuan Zhao, Feng
Gao, Tianjin Univ. (China)

10024-105, Session Post

Evaluation on the detection limit of blood
hemoglobin using photolepthysmography
based on path-length optimization
Di Sun, Chao Guo, Ziyang Zhang, Tongshuai Han, Jin Liu,
Tianjin Univ. (China)
The blood hemoglobin concentration’s (BHC) measurement using
Photoplethysmography (PPG), which gets blood absorption tonear infrared light from the instantaneous pulse of transmitted
light intensity, has not been applied to the clinical use due to thenon-enough precision. The main challenge might be caused of
the non-enough stable pulse signal when it’s very weak and it
often varies in different human bodies or in the same body withdifferent physiological states. We evaluated the detection limit of
BHC using PPG as the measurement precision level, which can beconsidered as a best precision result because we got the relative
stable subject’s pulse signals recorded by using a spectrometerwith high signal-to-noise ratio (SNR) level, which is about
30000:1 in short term. Moreover, we optimized the used pathlength using the theory based on optimum path-length to get abetter sensitivity to the absorption variation in blood. The best
detection limit was evaluated as about 1 g/L for BHC, and thebest SNR of pulse for in vivo measurement was about 2000:1 at
1130 and 1250 nm. Meanwhile, we conclude that the SNR of pulse
signal should be better than 400:1 when the required detection
limit is set to 5 g/L. Our result would be a good reference to the
BHC measurement to get a desired BHC measurement precisionof real application.

10024-106, Session Post

Evaluation and recognition of aging skin
images with aging by support vector
machineLiangjun Hu, Shulian Wu, Fujian Normal Univ. (China)
Aging is a very important issue not only in dermatology, but also
cosmetic science. Cutaneous aging involves both chronolgicaland photoaging aging process. The evaluation and classificationof aging is an important issue with the medical cosmetology
workers nowadays. The purpose of this study is to assess
chronological-age-related and photo-age-related of human skin.
The texture features of skin surface skin, such as orientationindex, coarse, were analyzed by Fourier transform and Tamura.
And the aim of it is to detect the object hidden in the skin texture
in difference aging skin. Then, Support vector machine wasapplied to train the texture feature. The different age’s states
were distinguished by the Support vector machine model. The
results help us to further understand the mechanism of different
aging skin from texture feature and help us to distinguish thedifferent aging states.

150

SPIE Photonics Asia·

In vivo tomographic imaging of the fluorescence pharmacokinetic
parameters in tissues can provide additional specific andquantitative physiological and pathological information to thatof fluorescence concentration. This modality normally requires
a highly-sensitive diffuse fluorescence tomography (DFT)
working in dynamic way to finally extracts the pharmacokinetic
parameters from the measured pharmacokinetics-associatedtemporally-varying boundary intensity. This paper is devoted toexperimental validation of our proposed direct reconstruction
scheme of instantaneous sampling based pharmacokinetic-DFT:
A highly-sensitive DFT system of CT-scanning mode working
with parallel four photomultiplier-tube photon-counting channels
is developed to generate an instantaneous sampling dataset;
A direct reconstruction scheme then extracts images of thepharmacokinetic parameters using the adaptive-EKF strategy. We
firstly investigate the principle validity of the experiment system
and reconstruction algorithm by designing a dynamic phantom
that can simulate the agent metabolism in living tissues, andthen the application feasibility of the propose methodology inrevealing metabolic rates of the fluorescence agent by imaging
healthy and tumor-bearing mice.

10024-108, Session Post

Accelerating data acquisition of largesized sample by propidium iodide-stained
contour extraction in real time
Xiaoyu Zhang, Qiuyuan Zhong, Jing Yuan, Hui Gong,
Qingming Luo, Huazhong Univ. of Science and Technology(China)Imaging large tissue and organs in 3D is critical to understandbiological process. Due to the contour irregularity of the largesized sample, a cuboid bigger than the sample in size would
be usually defined as imaging range to guarantee the integrityof imaging results. However, this approach has to acquire a lotof redundant data and sacrifice data acquisition time. Here, we
propose to a real-time contour extraction of propidium iodide(PI)-stained sample to define minimized imaging range for largesized sample to shorten data acquisition time. Immersing thesample in PI solution in several minutes before imaging could
stain the sample contour without polluting potential internal
fluorescent labels. Strong contrast of PI-stained contour enables
to extract the sample contour and then define minimized imaging
region in real time. To validate the efficiency of this method, weapply this method to wide-field large-volume tomography (WVT)
imaging. Benefit from this method, we achieve a data acquisitionof a 4-month-old SOM-cre mouse brain at the voxel size of 0.32
? 0.32 ? 2 ?m in 2.1 days, improving 38% from the one without
imaging range adjustment. The imaging mosaics of the dataset
is 0.65M, reducing 48% from the one without imaging range
adjustment. Our method can be generalized to other largesized tissue and organs to accelerate large-scale 3D imaging in
biological research.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-109, Session Post

Differentiation of highly-metastatic
nasopharyngeal carcinoma cells using
multiphoton microscopy
Zhenlin Zhan, Fujian Normal Univ. (China)
Nasopharyngeal carcinoma (NPC) is one of the most common
tumors in Southeast Asia and Southern China. It is often
associated with advanced clinical stage with higher incidence
of invasion and metastasis at the time of diagnosis. Hence, the5-year survival rate of patients with metastatic diseases is lessthan 60%. It is of great clinical value to further understand themetastatic status of cancerous cells and find valuable early
diagnostic markers as well as novel therapeutic strategies. The
primary hypothesis tested in the study was that NPC cells at
different stage of invasion and metastasis can be differentiatedusing multiphoton microscopy (MPM). Based on the developmentof the field of non-linear optics and femtosecond lasers, MPM canprovide real-time detailed information about cell morphology.
In this study, CNE1 and CNE2Z cells were cultured and used
for subsequent experiments. The activity of cell migration andinvasion was measured using Transwell migration and Transwellinvasion assays. At the same time, the morphologic features were
quantified from the multiphoton images. The results of Transwellmigration and invasion measurements showed that the invasion
and migration of CNE2Z cells were significantly enhanced whencompared with that of CNE1 cells. Also, statistically significant
differences in the morphologic features were found between
two kinds of cancer cells. In conclusion, it is feasible to use MPM
to differentiate cancer cells with different stage of invasion andmetastasis.

10024-110, Session Post

Measuring the biomechanical propertiesof actin in single breast cancer cell
Minghai You, Yuhua Wang, Ningcheng Jiang, Shusen Xie,
Hongqin Yang, Fujian Normal Univ. (China)
Biomechanics of cells play an important role in the behavior anddevelopment of diseases. Such forces could have a profoundinfluence on the health, structural integrity, and functionof cells. In this study, we proposed a method to assess theactin biomechanical properties in single breast cancer cellby combining structured illumination microscopy (SIM) withatomic force microscopy (AFM). High resolution optical imageof actin area in MCF-7 cell and its elastography were given.
The result shows that the optical image of actin via SIM could
improve about 40% in resolution than conventional wide field
fluorescence microscopy, which could give a precise local site
for AFM measurement. The elasticity of actin is about in therange of 10~100 kPa. It indicates that optical elastography andbiomechanics methods will aid in the understanding and clinicaldiagnosis of diseases at single cell level.

The research was supported by grant no. 14.575.21.0073, code
RFMEFI57514X0073 of the Ministry of Education and Science of
the Russian Federation

10024-112, Session Post

Parameter estimation and analysis model
selections in fluorescence correlation
spectroscopy
Shiqing Dong, Jie Zhou, Yuhua Wang, Shusen Xie,
Hongqin Yang, Fujian Normal Univ. (China)
Fluorescence correlation spectroscopy (FCS) is a powerful
technique that could provide high spatiotemporal resolution
and detection for the diffusions of biomolecules at extremely
low concentrations. The accuracy of this approach depends
on experimental condition requirements and the data analysis
model. We set up a laser confocal-based FCS system, andused a Rhodamine6G solution to calibrate the system and get
the related parameters. Then, we carried out an experimental
measurement in one component solution to evaluate therelationship between a certain number of molecules andconcentrations. The results showed FCS system was stable andvalid. Finally, a two-component solution experiment was done toshow the importance of analysis model selection. It is valuable forsingle molecular diffusion study in living cells using FCS.

10024-113, Session Post

Estimation of mouse optical structures invivo with the aid of image registration
Wenbo Wan, Feng Gao, Tianjin Univ. (China)

10024-111, Session Post

Childhood lymphoblastic leukemia
adverse drug reactions: study of risk
factors and therapy prognosis by opticalmethods
Andrey Zyubin, Anastasiya Lavrova, Svetlana Babak,
Vladimir Malaschenko, Anastasiya Borisova, Nikita
Opryishko, Immanuel Kant Baltic Federal Univ. (RussianFederation)

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We describe the study of children lymphoblastic leukemia
adverse drug reactions. We use a concentration of adenosine
triphosphate (ATP) as a marker to estimate processes ofhepatotoxic effects and drug resistance, during the therapy,
and show the applicability of confocal microscopy method forrevealing and working with cellar and mitohondrial concentrationof ATP. ATP is involved in the transport of the drug acrossthe cell membrane into the cell. Drug transport osmoticallysensitive and depends on the concentration of ATP. For example,
daunorubicinum, etoposide and vincristine transports into thecell at the concentration of cellular ATP 0.3 mg/l, 0.29 mg/l and0.28 mg/l, respectively. Experimental data from blood cells andits mitohondria was taken with a confocal microscope LSM 700(Carl Zeiss, Germany) using ZEN black Microscope and Imaging
Software Software (CarlZeiss, Germany). The luminescenceintensity value had been recorded.Detection was carried out
in the emission spectrum of lucefireine in the visible range of ~500-700 nm, with an expected maximum of about 536 nm. All
gained data of quantitative values for cellular and mitochondrial
ATP concentration had been calculated and allow us to markthe supposed correlation between the degrees of adverse drug
reactions and ATP concentration value. The model describes
correlation between hepatotoxic effects, drug resistance and ATPcellar and mitohondrial concentration had been created.

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The reconstruction quality in the model-based optical
tomography modalities can greatly benefit from a priori
information of accurate tissue optical-structures. Opticalstructures of tissue highly relies on its anatomical structures,
which can be obtained from anatomical imaging system such as
X-ray computed tomography (XCT). However, since X-ray offers
low soft-tissue contrast, segmentation of the abdominal organs
from XCT images can be problematic. In order to overcome thechallenges, the anatomical-structures of a target mouse areapproximately obtained through registering a standard mouseanatomical atlas, i.e., the Digimouse, to its XCT volume with nonrigid image registration, and the optical-structures of the target#PhotonicsAsia

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
mouse is approximately estimated when literature publishedoptical parameters are assigned to the registered anatomical
structures. Results of numerical simulations reveals that the
Digimouse can be effectively registered to the XCT volumes of
the target mouse, and the registered atlas shows well similarity
with the theoretical anatomical structures of the target mouse.
Result of mouse experiment have further demonstrated that the
proposed method is feasible to estimate optical structures of
the target mouse in vivo, which shows possibility for enhancing
the reconstruction of model-based optical tomography such as
fluorescence molecular tomography.

10024-116, Session Post

10024-114, Session Post

The phase characteristics and substructure shape analysis of a neuron basedon electrical-optical modeling

Novel shadowless imaging for eyes-like
diagnosis in vivo
Ning Xue, Kai Jiang, Qi Li, Tsinghua Univ. School of
Medicine (China); Lili Zhang, Li Ma, National Engineering
Research Ctr. for Beijing Biochip Technology (China);
Guoliang Huang, Tsinghua Univ. School of Medicine(China)Ying Ji, Tingting Hua, Wenbo Tang, Yuanyuan Xu, Yawei
Wang, Jiangsu Univ. (China)

Eyes-like diagnosis was a traditional Chinese medicine
method for many diseases, such as chronic gastritis, diabetes,
hypertension, etc. There was a close relationship between visceraand eyes-like. White-Eye was divided into fourteen sections,which corresponded to different viscera, so eyes-like was thereflection of status of viscera, in another words, it was an epitomeof viscera health condition.
In this paper, we developed a novel shadowless imaging
technology and system for Eyes-Like diagnosis in Vivo, which
consisted of an optical shadowless imaging device for capturing
and saving images of patients’ eyes-like, and a computer linked
to the device for image processing. A character matchingalgorithm was developed to extract the character of whiteeye in corresponding sections of eyes-like images taken by the
optical shadowless imaging device, according to the character ofeyes-like, whether there were viscera diseases could be learned.
A series of assays were carried out, and the results verified thefeasibility of eyes-like diagnosis technique.

10024-115, Session Post

Interstitial optical parameter
quantification of turbid medium based on
CW radiance measurements
Lingling Liu, Limin Zhang, Feng Gao, Huijuan Zhao, Tianjin
Univ. (China)
CW radiance measurements examine the light intensity at fixedsource-detector location from multiple detection directions which
thus is benefit for the noninvasive interstitial optical parameter
quantification. The CW radiance measurements are generally
needed to meet the requirement of small source detector
separation (SDS) and sample as few source-detector locations as
possible. Howerver, the diffuse approximation normally utilized
as a forward model for the recovery of optical parameters has alimitation at small SDS and in media with low albedo, in addition,
at least two source-detector locations are needed to sample.
In this paper, Monte Carlo (MC) simulations aimed at angularradiance are used to simulate experimental measurements andthe Pn approximation is used as the forward model for fitting torecover optical parameters at just one source-detector location.
Over a wide range of reduced albedo of medium between
0.69 and 0.99, the recovery errors of absorption coefficientand reduced scattering coefficient are less than 13.88%, 2.91%
respectively at 2mm SDS. The effects of the maximum angle
used for fitting and noise on optical parameter recovery have152

been further studied respectively in this paper. The results showthat the recovery errors of absorption coefficient and reduced
scattering coefficient are less than 7.43%, 2.58% respctively
when the maximum angle is 140 degree with minimum error
and the recovery errors of absorption coefficient and reduced
scattering coefficient less than 8.02%, 2.58% in 40 dB Gaussian
noisy. Experiments on a liquid phantom with a CW radiancemeasurement system are conducted and the results show thatthe optical parameters can be effectively recovered at just one
source-detector location.

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The research on electrical activity of a neuron has a verysignificant application in many fields, such as bioscience, clinicalmedicine and so on. It is very important to take images of the
sub-structure of a neuron due to that the morphology of which is
closely related to its function and the associated firing status aswell. Quantitative phase imaging is a technology which could get
the morphology information of an object non-invasively and nondestructively in full field at real time. Based on this technology
and optical simulation, a practical simplified model of a neuron
including cell body, axon and dendrite is established in this paperwith considering the relationship of the distribution of ions andthe refractive index of the cell. The related phase images are
gotten by the simulation as well. The optical phase characteristic
analysis of this model is given based on these phase images, thatis, the gradient calculation of the phase distributions and shapeanalysis of the phase diagrams are presented respectively. Thenthe sub-structure boundaries of the sample and the variation
characteristics of refractive index of the object are obtained.
From which, the information of the distribution of ions as wellas the associated firing status of the neuron can be indicatedintuitively to some extent. This work could provide a new method
for the research on firing behavior analysis of neurons or otherbiological cells.

10024-117, Session Post

Dorsal hand vein recognition based on
Gabor multi-orientation fusion and multiscale HOG features
Tuo Han, Zhiyong Wang, Xiaoping Yang, Tianjin Univ. ofTechnology (China)
Kinds of factors such as illumination and hand gestures would
reduce the accuracy of dorsal hand vein recognition.Aiming at
single hand vein image with low contrast and simple structure,analgorithm combining Gabor multi-orientation features fusion
with Multi-scale Histogram of Oriented Gradient (MS-HOG) is
proposed in this paper.With this method,more features will be
extracted to improve the recognition accuracy.Firstly,diagramsof multi-scale and multi-orientation are acquired using Gabortransformation,then the Gabor features of the same scale
and multi-orientation will be fused,and the features of thecorrespondent fusion diagrams will be extracted with a HOG
operator of a certain scale.Finally the multi-scale cascaded
histograms will be obtained for hand vein recognition.The
experimental results show that our method not only improve therecognition accuracy but has good robustness in dorsal hand vein
recognition.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-118, Session Post

10024-120, Session Post

Discrimination of liver cancer in cellularlevel based on backscatter microspectrum with PCA algorithm and BP
neural network

Compact hybrid real-time hyperspectral
imaging system with high effective spatial,
spectral, and temporal resolution

Jing Yang, Univ. of Shanghai for Science and Technology(China)The incidence and mortality rate of the primary liver cancer
are very high and its postoperative metastasis and recurrence
have become important factors to the prognosis of patients.
Circulating tumor cells (CTC), as a new tumor marker, play
important roles in the early diagnosis and individualized
treatment and CTC also have induced the interest of researchers.
This paper presents an effective method to distinguish livercancer based on the cellular scattering spectrum, which is a nonfluorescence technique based on the fiber confocal microscopic
spectrometer. The principal component analysis (PCA) and backpropagation (BP) neural network was utilized to establish an
automatic recognition model for backscatter spectrum of theliver cancer cells. Principal component analysis was applied toreduce the dimension of the cell spectral data which obtainedby the fiber confocal microscopic spectrometer. We establisheda neural network pattern recognition model with 2 input layer
nodes, 11 hidden layer nodes, 3 output nodes. We trained the
network with 66 samples and also tested it. Results showed thatthe recognition rate of the three types of cells is more than 90%,
the relative standard deviation is only 2.36%. The experimental
results showed that the fiber confocal microscopic spectrometer
combining with the algorithm of PCA and BP neural network can
automatically identify the liver cancer cell from the blood cells.
This will provide a better tool for investigating the metastasisof liver cancers in vivo, the biology metabolic characteristics ofliver cancers and drug transportation. Additionally, it is obviously
referential in practical application.

10024-119, Session Post

Analysis of human hairs by femtosecond
laser-induced breakdown spectroscopy
Yuliya S. Biryukova, Sergey S. Golik, Alexey A. Ilyin, Tamara
M. Agapova, Michael Y. Babiy, Far Eastern Federal Univ.
(Russian Federation); Alexander Y. Mayor, Institute for
Automation and Control Processes (Russian Federation);
Nataliya Golik, Institute of Automation and Control
Processes (Russian Federation); Elizabeth Pripatinskaya,
Far Eastern Federal Univ. (Russian Federation)
The time-resolved femtosecond laser-induced breakdown
spectroscopy (LIBS) was used to analyze human hairs. Spitfire
Ti:sapphire amplifier system (Spectra-Physics) was used as asource of femtosecond laser pulses (<45 fs, pulse energy up to5 mJ) and ICCD cameras (PicoStar HR, LaVision and PI-MAX3,
Princeton Instruments) coupled with 2500i or 2300 Acton
SpectraPro spectrographs were used as a detectors. Plasma
was generated by focusing laser radiation directly on the glued
strand of hairs. Gate delays were varied from 0 to 200 ns andkinetic of luminescence of emission lines and background spectra
were obtained in spectral range of 200-750 nm. Measurementsof different social classes were carried out. Correlation between
concentrations of elements (Na, Ca, K, Mg) in hairs was obtained.
It is shown that femtosecond LIBS can be a promising technique
for the analysis of essential and toxic elements in hair and allows
to diagnose disorders of mineral metabolism in the human body.

Filip Roth, Masaryk Univ. (Czech Republic) and IBSmm
Engineering, spol. s r. o. (Czech Republic); Ahmad Abbadi,
Masaryk Univ. (Czech Republic)
Medical endoscopes for image-guided surgery commonly use
standard color image sensors, discarding any more detailed
spectral information. Medical spectroscopy devices with various
spectral working ranges are specialized to specific medical
procedures and in general are not usable for image-guided
surgery due to limitations in spatial or temporal resolution.
In this paper, we present an initial demonstrator of hyperspectral
endoscope, composed of two image sensors with complementing
parameters. Using this hybrid approach, combining sensors withdifferent spatial and spectral resolutions and spectral ranges,
we obtain improved coverage of all the respective parameters.
After digitally processing and merging the video streams, while
maintaining the better features of both, we obtain an imaging
system providing high effective spatial, spectral and temporal
resolution.
The system is based on field programmable gate arrays andprovides real-time video output (60 Hz), which is usable fornavigation during image-guided surgery. The flexible systemarchitecture allows for an easy extension of the processing
algorithms and enables minimal video signal latency.
Physical dimensions and portability of the system are comparable
to standard off-the-shelf medical endoscope cameras. The device
can output both processed video and standard visible light video
signals on one or more video outputs of the system. The resulting
processed video signal obtained from the combined image
sensor data greatly increases the amount of useful information
available to the end user.

10024-121, Session Post

Interferometer immunosensor based on
porous silicon for determining alphafetoprotein
Xiao-yi Lv, Xinjiang Univ. (China)
Alpha-fetoprotein ( AFP) is a kind of plasma glycoprotein
synthesized by human liver in the early stage. An increased levelof AFP in the blood may be a sign of liver cancer. Normal human
AFP protein content is very low, less than 20ng/L.According
to the survey found that in the serum of about 80% patientswith hepatocellular carcinoma, the AFP will increase, generally
in the 8 months before the onset of symptoms of liver cancer
has increased.In this paper,porous silicon based optical FabryPerot cavity structure is prepared as a label-free immunosensor
platform for detecting AFP. After the antigen-antibody reaction,
it is monitored that the red shift of the reflection spectrum of
the immunosensor increases with the antigen concentration.This
research also plays a potential role for the extensive applicationsin immunoassay.

10024-122, Session Post

Label-free and high-sensitive detection
for genetic point mutation based on
hyperspectral interferometry
Rongxin Fu, Qi Li, Junqi Zhang, Ruliang Wang, Xue

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Conference 10024:
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10024-124, Session Post

Lin, Ning Xue, Ya Su, Kai Jiang, Tsinghua Univ. (China);
Guoliang Huang, Tsinghua Univ. School of Medicine(China)Label free point mutation detection is particularly momentous
in the area of biomedical research and clinical diagnosis sincegene mutations naturally occur and bring about highly fatal
diseases. In this paper, a label free and high sensitive approach is
proposed for point mutation detection based on hyperspectralinterferometry. A hybridization strategy is designed todiscriminate a single-base substitution with sequence-specific
DNA ligase. Double-strand structures will take place only if added
oligonucleotides are perfectly paired to the probe sequence. The
proposed approach takes full use of the inherent conformation of
double-strand DNA molecules on the substrate and a spectrum
analysis method is established to point out the sub-nanoscale
thickness variation, which benefits to high sensitive mutation
detection. The limit of detection reaches 4pg/mm2 according to
the experimental result. A lung cancer gene point mutation wasdemonstrated, proving the high selectivity and multiplex analysis
capability of the proposed biosensor.

10024-123, Session Post

Application of CRDS laser breath acetone
analyzer in fat burning
Xiaomeng Zhao, Meixiu Sun, Zhannan Wang, Hao Yang,
Yingxin Li, Chinese Academy of Medical Sciences (China);
Chuji Wang, Chinese Academy of Medical Sciences(China) and Mississippi State Univ. (United States)
Breath acetone is the production in the process of fat
metabolism. Through measuring the breath acetone
concentration, we can track the fat metabolism in healthy
individuals. The method is suitable for the person being reduced
fat, which can eliminate the interference of water and inspire thepower of fat burning. At the same time, it can prevent the riskof personal injury due to the high ketone body. In order to show
the advantage of breath acetone monitoring in fat burning, we
recruit 14 healthy volunteers who are in the process of fat loss.
The breath acetone, urine ketone, weight, BMI and body fat ratein the fasting state for 21 days are recorded, while the dietaryintake calories and the sport consumption calories are recorded
too. The breath acetone is measured by the CRDS laser breath
acetone analyzer.
The experiment results show that the average breath acetone ofvolunteers who loss more weight is higher than those loss lessweight in 21 days. The fasting breath acetone concentration has
the same change trend with weight and body fat rate generally.
While the urine ketone show ++ and +++, the acetone breath
acetone increases dramatically, which has significant statisticaldifferences. The experiment also shows that the fat is consumed
slowly under the common action of reduced diet and increased
sports. When the net calories of volunteers keep in a low levelfor days, the weight and body fat rate would drop slowly, and thebreath acetone increase gradually. However in the process of fat
burning, when the dietary intake of calories increases suddenly,
breath acetone will decrease rapidly in one day, the weight andbody fat rate will rise slowly. So we can fast know the quantitative
and accurate fat burning state by monitoring the fasting breath
acetone, which can help us to adjust the fat loss plan timely,
avoid the injury due to the high ketone body, achieve the purpose
to lose fat in healthy method.

Application study of transport intensity
equation in quantitative phasereconstruction
Xiaojun Song, Shanghai Univ. of Electric Power (China);
Wei Cheng, Chunjuan Wei, Shanghai Univ. of ElectricPower (China); Baodan Bai, Shanghai Univ. of Medicine& Health Sciences (China); Liang Xue, Fenghong Chu,
Shanghai Univ. of Electric Power (China); Weijing Liu,
Shanghai University of Electric Power (China)
In order to improve detection speed and accuracy of biologicalcells, a quantitative non-interference optical phase field method
is proposed in commercial microscope, taking the red blood cells
as the classical phase research objects. This method not only
gives quantitative phase distribution of cells quickly, but alsomeasure a large number of cells at the same time. Three brightfield micrographs were collected in the experiment. Utilizing thetransport intensity equation, the quantitative phase distributionsof red blood cell are gained and agree well with the previous
optical phase models. Analysis shows that the resolution of
introduced system reaches sub-micron dimension. This method
is potential in the use of real-time observing and quantitative
analyzing of cells in vivo.

10024-125, Session Post

Photophysical property of the pyridyl
and pyrimidinyloxy silicon (IV)phthalocyanines and their morphology ofpolymeric nanoparticles
Yiru Peng, Sujuan Pan, Ting Lin, Shijun Wu, Yufeng Jiang,
Di Zeng, Hongqin Yang, Yide Huang, Fujian Normal Univ.
(China)Phthalocyanines (Pcs) are extensively studied by many scientists
because of their interesting optical, electrical properties andgood thermal stability. The unsubstituted Pcs can present
solubility and aggregation behaviour problems for limiting theirapplications. In our study two pyridyl and pyrimidinyloxy silicon(IV) phthalocyanines were synthesized. Their photophysicalproperties were examined by UV-Vis, steady-state and timeresolved fluorescence spectroscopic methods. The positionsof Q band were observed at 670 nm for two phthalocyanines.
Compared with silicon phthalocyanine dichloride (SiPcCl2),
the fluorescence intensities and lifetimes of two pyridyl andpyrimidinyloxy silicon (IV) phthalocyanines increased. In orderto improve biocompatibility and tumor-targeted delivery, thehydrophobic dendritic phthalocyanine were encapsulated bydiblock amphiphilic copolymer poly (N’-benzyl oxygen carbonyllysine)-poly (ethylene glycol)-poly (N’-benzyl oxygen carbonyllysine) (PLL(Z)-PEG-PLL(Z)) to form the polymeric nanoparticles.
The morphology of two nanoparticles were investigated by using
atomic force microscope. The polymeric nanoparticle is sphericalwith a diameter at about 35 nm. The polymeric nanoparticles
would be the promising third-generation photosensitizer (PS) for
PDT.

10024-126, Session Post

Dual-modal in-vivo imaging system
for small animal using individual novel
detector OptX
Ruliang Wang, Tsinghua Univ. (China); Junqi Zhang, Qi Li,
154

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
Rongxin Fu, Ning Xue, Tsinghua Univ. School of Medicine(China); Xue Lin, Ya Su, Tsinghua Univ. (China); Kai Jiang,
Tsinghua Univ. School of Medicine (China)
Multimodal imaging system which always combines imaging
modalities providing structural information with modalities
providing functional information plays an important role inanimal research. A lot of multi-modal imaging system has beenreported and used in different area of biomedical research. Whilemost reported multi-modal imaging systems employ separated
detector for each modality and always have difficulties inmerging multi-modal information.
Herein, we present a novel detector – OptX capable of detecting
both high-energy X-ray and optical wavelength photons. The
design concept of this detector is discussed and a prototype
detector is demonstrated. A dual-modal imaging system basedon this detector is designed and established, which realized
optical molecular imaging and X-ray based imaging. No extra
marker or algorithm is needed for registration and merging two
modalities. Dual-modal imaging is successfully performed withthis imaging system. The performance (resolution and field ofview) of this imaging system is evaluated. The results indicatethat the construction of this OptX detector and a dual-modal
imaging system based on it is feasible.

10024-127, Session Post

2D light scattering label-free cytometry
using light-sheet illumination
Meiai Lin, Xuantao Su, Shandong Univ. (China)
Flow cytometry that measures optical signals from biologicalcells has wide application in many fields such as biomedicine.
Conventionally the cells are labeled with fluorescent dyes toobtain detailed cellular information, which is complex and may
interrupt the cell function. Compared with fluorescent labeling,
two-dimensional (2D) light scattering cytometry is an effective
label-free technology for cell analysis.
Light-sheet technique has been introduced into fluorescencemicroscopy in recent years. Here we adopt the light-sheet
illumination in 2D light scattering static cytometry. The lightsheet restricts the excitation volume near the scatter, thus
reduces background noise. In our cytometer, a cylindrical lens
is used to form light-sheet and a sample chamber is fabricatedfor better excitation of the cells under an inverted microscope.
Two-dimensional light scattering patterns are obtained by acomplementary metal oxide semiconductor (CMOS) detector via
a low numerical aperture (NA 0.4) objective lens.
The thickness of the light-sheet measured in fluorescent solution
is about 10 ?m. Two-dimensional light scattering patterns of
single polystyrene microspheres with 3.87 ?m in diameter are
obtained. The experimental patterns characterized with fringe
structure agree well with the Mie theory simulated ones. We
further demonstrate that the technique developed here can beused for yeast cell size determination. Our results suggest thatthe light-sheet illumination is an effective excitation method forlabel-free cytometry and light-sheet-based 2D light scattering
static cytometry has the potential for cell diagnostics.

10024-128, Session Post

The effect of metal ions on thephotophysical and photochemical
properties of bromo dendrimer metal
phthalocyanines

Kuizhi Chen, Shusen Xie, Hongqin Yang, Fujian Normal
Univ. (China)
Phthalocyanines (Pcs) have attracted great attention becauseof their applications in material science including electrooptical devices, electrochromic display, and photodynamic
therapy (PDT) of cancer. The photophysical and photochemical
properties of Pcs can be modulated by either peripheral
substituents or metal ions co-ordination to central cavity ofhighly conjugated tetrapyrrolic macrocycles. However, because of
the hydrophobic nature of the Pcs ring, Pcs have strong tendency
to aggregate in solution, which limited their applications. To
overcome this problem, the introduction of dendritic wedge
to peripheral positions of phthalocyanines can prevent theformation of aggregation to some extent. The photophysical andphotochemical properties of metal dendritic phthalocyanines
were studied by UV/Vis and fluorescence spectroscopic
methods. The result indicated that the photophysical propertiesof dendrimer zinc (II) phthalocyanine exhibited metal ionsdependence. Compared with the magnesium (II) phthalocyanine,
the intensity of Q band of zinc (II) phthalocyanine was increased
but no obviously position change was observed. Meanwhile,the fluorescence intensity of zinc (II) phthalocyanine exhibited
relatively higher than the magnesium (II) phthalocyanine.
Whereas the fluorescence quantum yield and lifetimes ofmagnesium (II) phthalocyanine was clearly longer than thatof zinc (II) phthalocyanine. The singlet oxygen quantum yieldof zinc (II) phthalocyanine was higher than the magnesium(II) phthalocyanine. This results indicated that the zinc (II)phthalocyanine is a better candidate for photodynamic therapyof cancer.

10024-129, Session Post

Monitoring the changes of mitochondrial
morphology and its metabolism of breast
cancer cells with the treatment of HSP70
inhibitor after heat shock by fluorescenceimaging
Biying Yu, Hongqin Yang, Hui Li, Fujian Normal Univ.
(China)Heat shock (HS) is one of the best-studied exogenous cellularstresses, and all cellular compartments and metabolic processes
are involved in HS response. The heat shock protein (HSP)
expression enhanced during HS mainly localized in subcellularcompartments, such as cytosol, endoplasmic reticulum andmitochandria. The major inducible heat shock protein 70 (HSP70)
modulate cellular homeostasis and promote cellular survivalby blocking a caspase independent cell death through its
association with apoptosis inducing factor. Mitochondria as thecritical elements of HS response that participate in key metabolic
reactions, and the changes in mitochonrial morphology may
impact on mitochondrial metabolism. In this paper, the changesof mitorchondrial morphology in breast cancer cell have beenmonitored in real time after heat shock (43?) by the fluorescenceimaging, and the influence of HSP70 inhibitor on mitochandrial
structures have also been investigated. Then the information of
mitochondrial metabolism which can be characterised by thelevel of the mitochondrial membrane potential has also beenobtained wihout/with the treatment of HSP70 inhibitor. Our data
indicated that the mitochandrial morphology were related withthe mitochandrial membrane potential, and the mitochandrial
membrane potential was influenced significantly with thetreatment of HSP70 inhibitor after HS.

Yiru Peng, Sujuan Pan, Dongdong Ma, Tiantian Zhang,

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-130, Session Post

suggests different brain activity mode in response to posturechange in the elderly subjects compared to young subjects andthis may be useful in assessing the risk of postural instability inaged persons.

Vigilance task-related functional
connectivity revealed by wavelet-based
coherence analysis of near-infrared
spectroscopy signals

Acknowledgements: This project was supported by the National
Natural Science Foundation of China (Grant No. 31371002,
81071223).

Wei Wang, Lingguo Bu, Liwei Xu, Shandong Univ. (China);
Zengyong Li, National Research Ctr. for Rehabilitation
Technical Aids (China)
During a cognitively demanding task such as driving, attention
cannot always be maintained at a high level, as time elapses,
the level of attention progressively diminishes, which impacts
task performance negatively. This study assesses the vigilancetask-related functional connectivity in healthy adults using the
wavelet-based coherence analysis of near-infrared spectroscopy
signals (NIRS). NIRS is a non-invasive method that continuously
monitors brain activity by measuring the absorption of nearinfrared light through the intact skull. A vigilance task was
designed to simulate driver mental load in real-car driving.
Three numbers changed randomly every second on the screen,
the subjects need to immediately step on the brake pedal (i.e.,
within 1.3 s) when the three numbers are different odd numbers.
Continuous recordings of NIRS signals were obtained from theprefrontal cortex (PFC) and sensorimotor cortical areas of 20
young healthy adults (24.9±3.3 years) during 10-min restingstate and 10-min vigilance task state. Wavelet phase coherence(WPCO) was obtained as the NIRS signals were analyzed
by wavelet transform, which reveal possible relationship byevaluating the match between the instantaneous phases of
two signals. WPCO of six channel pairs were calculated in fivefrequency intervals: 0.6–2 Hz (I), 0.145–0.6 Hz (II), 0.052–0.145
Hz, (III) 0.021–0.052 Hz (IV), and 0.0095–0.021 Hz (V). The results
show significant GC (global connectivity) levels in interval I and
FC (functional connectivity) levels in interval III were significantly
lower in the task group than in the rest group, particularly
between the left PFC and bilateral sensorimotor regions.

10024-131, Session Post

Age-related changes in brain functional
connectivity in response to posturechange as assessed by wavelet phasecoherence of NIRS signals

Linyan Xie, Qiaoxi Liu, Changshun Shao, Xuantao Su,
Shandong Univ. (China)
We have recently developed a 2D light scattering static
cytometer for cellular analysis in a label-free manner, whichmeasures side scatter (SSC) light in the polar angle range from79 to 101 degrees. Compared with conventional flow cytometry,
our cytometric technique requires no fluorescent labeling of thecells, and static cytometry measurements can be performed
without flow control. In this paper we present an improved labelfree static cytometer that can obtain 2D light scattering patterns
in a wider angular range.
By illuminating the static microspheres on chip with a scanning
optical fiber, wide-angle 2D light scattering patterns from single
standard microspheres with a mean diameter of 3.87 ?m are
obtained. The 2D patterns of 3.87 ?m microspheres contain bothlarge angle forward scatter (FSC) and SSC in the polar angle
range from 40 to 100 degrees. Fourier analysis of experimentallyobtained 2D patterns from 3.87 ?m microspheres are in good
agreement with Mie theory simulated ones. The wide-angle 2D
light scattering measurements may provide a better resolution
for particle analysis as compared with the SSC measurements.
Two-dimensional light scattering patterns from HL-60 humanacute leukemia cells are obtained by using our static cytometer.
Compared with SSC 2D light scattering patterns, wide-angle
2D patterns contain richer information of the HL-60 cells. The
obtaining of 2D light scattering patterns in a wide angular range
could help to enhance the capabilities of our label-free static
cytometry for cell analysis.

Diffuse reflectance spectroscopy studyof in vitro tissue for nasopharyngeal
carcinoma diagnosis

Postural instability (PI) and falls is commonly seen due to aging
and motor disabilities. Functional connectivity (FC) is broadly
used to evaluate the correlation level between different regions
or within local regions of the human brain. Wavelet phasecoherence (WPCO) can discover possible correlations between
two signals by evaluating how well the two instantaneous phasesfrom the signals are matched. This study aims to assess thedifference in brain functional connectivity in response to posturechange between elderly subjects and young subjects by the
WPCO values of ?[HbO2] signals measured with NIRS method.
The NIRS signals were continuously recorded from the prefrontal
cortex and sensorimotor cortical areas in 17 healthy elderly
subjects and 20 young healthy subjects during 10 min restingstate and 10 min standing state. The WPCO were calculated infive frequency intervals in each channel pair. Two-Way ANOVA
was used to check whether there were significant interactions
between age and posture factors.
In summary, the present study showed that a sit-to-stand posturechange task had significant effect on the FC and the global
connectivity (GC) in the elderly subjects. The present results
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Development of wide-angle 2D lightscattering static cytometry

10024-133, Session Post

Bitian Wang, Shandong Univ. (China); Zengyong Li,
Shandong Univ. (China) and National Research Ctr. for
Rehabilitation Technical Aids (China)

156

10024-132, Session Post·

Zhihong Xu, Xiaosong Ge, Xueliang Lin, Duo Lin, Wei
Huang, Fujian Normal Univ. (China)
Diffuse reflectance spectroscopy is a non-contact, non-invasive,and low-cost optical technique that provides real-time feedback
about the absorptive characteristics and the microstructure
properties of biological tissue. This optical technique shows
the potential for monitoring metabolic status associated withmalignancy transformation. Nasopharyngeal carcinoma is thethird most frequently diagnosed cancer associated with virus
and is the most common male malignancy with a characteristic
regional and racial distribution worldwide. This paper provides an
overview on the applications of diffuse reflectance spectroscopy
in the cancer detection and also investigates the current
screening state of nasopharyngeal malignancies. Futhermore,
the latest research relevant to the diagnosis of nasopharyngeal
cancer in vitro tissue using diffuse reflectance spectroscopy is
introduced. The results of diffuse reflectance spectroscopy aresummarized, showing a significant experimental and clinical value
for further nasopharyngeal carcinoma detection in vivo in the
future.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-134, Session Post

10024-136, Session Post

Photophysical properties of catechol
axially-substituted tetra-[alpha](pentyloxy) titanium (IV) phthalocyanine

Absolute flow velocity measurement bydepth-encoded dual-beam phase-resolved
Doppler optical coherence tomography

Yiru Peng, Xinxin Yu, Huafei Lv, Sujuan Pan, Shijun Wu,
Di Zeng, Yufeng Jiang, Hongqin Yang, Shusen Xie, Fujian
Normal Univ. (China)

Jie Qian, Wei Cheng, Zhaoyuan Cao, Xinjian Chen, Jianhua
Mo, Soochow Univ. (China)

Metal phthalocyanines (MPcs) have been found to be a promising
photosensitizers for photodynamic therapy (PDT) of cancers
and non-cancer diseases. Nevertheless, phthalocyanines aresubstantially limited in clinical applications owing to their poor
solubility, aggregation and insufficient selectivity for cancer
cells. Catechol is an important pharmaceutical intermediate,
important in vivo biological activity. It plays an importantrole in medicine. Using catechol?pyrocatechin?asaxial ligands, utilizing of the pharmaceutical effect of
catechins, could improve the bioavailability, and achievesynergistic therapeutic effect in PDT. To address these issues, anovel catechol axially substituted tetra-?-(pentyloxy) titanium(IV)(TiPc(OC5H11)4-Catechol) was synthesized. The structure
TiPc(OC5H11)4-Catechol was characterized by elemental analysis,
IR, 1HNMR, MS methods. The photophysical properties ofTiPc(OC5H11)4 and TiPc(OC5H11)4-Catechol have been studied
by UV/Vis and steady-state fluorescence spectra. After being
axially substituted with catechin groups, no obviously intensityand position of maximum wavelength in Q-band of
TiPc(OC5H11)4 and TiPc(OC5H11)4-Catechol was observed. The
fluorescence intensity of TiPc(OC5H11)4 is stronger than thatof TiPc(OC5H11)4-Catechol, but the fluorescence lifetime ofTiPc(OC5H11)4-Catechol is a longer than that of TiPc(OC5H11)4.
TiPc(OC5H11)4-Catechol may be considered as a promising
photosensitizer for PDT.

Phase-resolved Doppler optical coherence tomography (PR-DOCT) is a functional OCT imaging technique that can provide
fast and high-resolution depth-resolved measurement on flowin biological materials. However, a common problem withconventional PR-D-OCT is that this technique often measures
the flow motion projected onto the OCT beam path. Without
knowing the projection angle ? between vessel orientationand the OCT beam path, it is hard to obtain the absolute flow
velocity. Moreover, the projection angle is usually missing forin vivo measurement on human blood vessel, which obscuresquantitative study on human blood flow. In this paper, we
proposed a novel dual-beam PR-D-OCT method to measureabsolute flow velocity, which does not require knowing the
projection angle. The sampling beam is divided into two equalbeams and separated laterally before being focused into samples,
which leads to two different incident angles. The images by thetwo beams are encoded to different depths in individual B-scan.
Thus, upon single B-scan, with the Doppler signals measured by
the two beams and the difference between the incident angles of
the two beams, we can calculate the absolute flow velocity. We
validated our approach in vitro on an artificial flow phantom on
our home-built 1060 nm swept source OCT. The flow phantom isa capillary with 400-?m diameter perfused with milk at constant
speed by a syringe pump. Experimental results demonstrated
that our method can provide an accurate measurement of
absolute flow velocity without the projection angle.

10024-135, Session Post

10024-137, Session Post

Functional connectivity analysis using
fNIRS in healthy subjects during
prolonged simulated driving

Integrated acoustic-resolution and opticalresolution photoacoustic microscopyusing a single multifunctional acoustic lensLiwei Xu, Bitian Wang, Wei Wang, Zhian Liu, Shandong
Univ. (China); Zengyong Li, National Research Ctr. for
Rehabilitation Technical Aids (China)

Heng Guo, Lei Xi, Univ. of Electronic Science andTechnology of China (China)

The present research proposed the assessment of cerebral
functional connectivity (FC) during drawn-out simulated driving.
Synergistic mechanisms in relevant brain regions were monitored
by a driving simulator combined with fNIRS technology. 14
subjects were recruited to complete a primary driving tasks
accompanied by a secondary mental task. Wavelet coherence(WCO) and wavelet phase coherence (WPCO) were calculated
in frequency intervals: I, 0.6–2 Hz; II, 0.145–0.6 Hz; III, 0.052–0.145
Hz; IV, 0.021–0.052 Hz; V, 0.0095–0.021 Hz; and VI, 0.005–0.0095
Hz. The connectivity (WCO and WPCO) in intervals I and II was
defined as global connectivity (GC), and that in intervals III–V
was FC. Significantly lower connectivity levels (WCO and WPCO)
were found in intervals I and III in prefrontal cortex (PFC), andsignificantly lower connectivity levels (WCO and WPCO) ininterval IV in motor cortical areas by the end of the driving task.
The results show that the lower GC in interval I in the PFC and thelower FC in intervals III and IV in the PFC and motor cortical areas
are closely related to driving fatigue. A decreased connectivity
indicates decreased cognitive functions in the PFC and reduced
coordination among the PFC and motor cortical areas.
Acknowledgements

With the rapid development of photoacoustic imaging, it has
been widely used in various research fields such as biology,
medicine and nanotechnology. Due to the huge difference
among photoacoustic imaging systems, it is hard to integratethem in one platform. To solve this problem, we propose todevelop a new universal photoacoustic imaging platform that
integrates acoustic-resolution photoacoustic microscopy
and optical-resolution photoacoustic microscopy through amultifunctional liquid lens. This lens takes advantage of an
inherently low acoustic impedance and a tunable focal lengththat was characterized by the infusion volume of the liquid. In
this paper, the liquid lens was used to realize confocal of laser
illumination and acoustic detection for both acoustic-resolution
and optical-resolution photoacoustic microscopy. The homemade polyvinylidene fluoride (PVDF) acoustic transducer hada center frequency of 10MHz and -6dB frequency spectrum
from 4MHz to 15MHz which yielded to an axial resolution of 70?m. The lateral resolutions of acoustic- and optical-resolution
photoacoustic microscopy were evaluated to be 180 ?m and4.8 ?m, respectively. The vasculature of rabbit and rat ears werecarried out respectively to evaluate the performance of acousticand optical-resolution photoacoustic microscopy.

This project was supported by the National Natural Science
Foundation of China (Grant No. 31371002, 81071223).

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-138, Session Post

En-face sectional imaging using singleshot full-field optical coherence
tomography (SS-FF-OCT) based on whitelight-emitting diode (WLED)
Tulsi Anna, National Yang-Ming Univ. (Taiwan); Ting-Wie
Chang, Industrial Technology Research Institute (Taiwan);
Chih-Ming Lai, Ming Chuan Univ. (Taiwan); Wen-Chuan
Kuo, National Yang-Ming Univ. (Taiwan)
Full-field optical coherence tomography (FF-OCT) is aninterferometric technique that utilizes spatially incoherent broadband illumination, using thermal, halogen and xenon arc lamp,
to provide high-resolution en-face sectional images of biologicaland engineering materials1. However, white light emitting diodes(WLED)2 also have potential to be used in FF-OCT systems due
to its higher energy efficiency, longer life time, compact, and also
capable to provide high axial resolution that still to be explored
to its potential in tomographic imaging. This work presents acost-effective Linnik type single shot FF-OCT (SS-FF-OCT)
system comprising a single WLED light source (wavelength range
470-850nm, central wavelength 650nm) and a CMOS device. The
measured axial resolution is 0.9?m. For broader applications, low
NA ≈ 0.1 objectives are used in the present system. The measured
imaging area and lateral resolution are 1.0 x 1.0mm2 and ≈ 4.2?m,respectively.
The en-face sectional imaging is useful to obtain temporal
information within the en-face plane. In this work, to achieve
faster en-face imaging, a single shot Riesz transform (RT)3
demodulation scheme with background subtraction, that
improves the time resolution limited by conventional phaseshifting methods, has been utilized. The detail performance ofpresent SS-FF-OCT system is demonstrated by imaging of fishskin and plant leaves. The present SS-FF-OCT is cost-effective
due to low cost WLED and no phase shifting device, compact,
fast (RT based scheme) and also significantly stable for the phasemeasurement. This system has the potential to be applied indynamical phenomena such as in vivo biological samples.
Reference:
1. W. Drexler and J. G. Fujimoto, Optical Coherence Tomography,
Technology and Applications (Springer, 2008).
2. C. Li, et al., “Non-destructive Evaluation of Polymer Coating
Structures on Pharmaceutical Pellets Using Full-Field Optical
Coherence Tomography,” Jr. of Pharmaceutical Sci. 103,161-166(2014).
3. S. E. Schausberger, et al., “Full-field optical coherence
microscopy with Riesz transform-based demodulation for
dynamic imaging,” Opt. Lett. 37, 4937-4939 (2012).

to image the whole body of adult zebrafish with micro-scale
resolution. However, the method called photoacoustic imaging
that combines all the advantages of the optical imaging andultrasonic imaging provides a new way to image the wholebody of the zebrafish. In this work, we developed a non-invasive
photoacoustic imaging system with optimized near-infrared
illumination and cylindrical scanning to image the zebrafish.
The lateral and axial resolution yield to 80 ?m and 600 ?m,respectively. Multispectral strategy with wavelengths from 690
nm to 930 nm was employed to image various organs inside
the zebrafish. From the reconstructed images, most majororgans and structures inside the body can be precisely imaged.
Quantitative and statistical analysis of absorption for organs
under illumination with different wavelengths were carried out.

10024-140, Session Post

Revealing the cellular metabolism
and microstructural changes in vivo insenescing Acer saccharum leaves using
two-photon FLIM and full-field OCM
Sandeep Chakraborty, Tulsi Anna, Wen-Chuan Kuo, Arthur
E. Chiou, National Yang-Ming Univ. (Taiwan)
Seasonal as well as climate changes have immense effect on bud
burst, leaf color and leaf abscission. Autumn phenology of leaves
is clearly distinguishable in deciduous plant leaves where changesof leaf color occur from green to red (leaf senescence).1 In thiswork, two-photon fluorescence lifetime imaging microscopy(2P-FLIM)2 and full-field optical coherence microscopy (FFOCM)3 were applied to study mitochondrial activity as well asinternal morphological microstructure in senescence of Acersaccharum (Sugar maple) leaves, respectively. Fluorescence
lifetime of reduced nicotinamide adenine dinucleotide [NAD(P)H] was recorded using 2P-FLIM to quantify the cellular
mitochondrial metabolic changes. Compared to the green leaves,the red leaves showed a 19% increase (p < 0.05) in the average
fluorescence lifetime of NAD(P)H, and a 34% decrease (p <0.005) in the free to protein-bound NAD(P)H ratio. This infers asignificant change in mitochondrial metabolic regulation in red
leaves in contrast to green leaves. Additionally, en-face sectional
images at 0.8 µm axial resolution of the green and red color
Acer saccharum leaves via FF-OCM using white LED showed awell-defined morphological microstructure in cuticle and upper
epidermis in red leaves as compared to green leaves where morediffuse internal microstructure was observed. In contrast, surface
scattering was much higher in green leaves than red leaves. Our
approach can potentially be used to correlate mitochondrial
activity with internal microstructural changes in other biologicalsystems.
References
1. L. V. Junker & I. Ensminger, “Relationship between leaf opticalproperties, chlorophyll fluorescence and pigment change insenescing Acer saccharum leaves,” Tree Physiol. 00, 1-18 (2015).

10024-139, Session Post

Whole-body and multispectral
photoacoustic imaging of adult zebrafish

2. W. Becker, “Fluorescence lifetime imaging-techniques andapplications,” J. Microsc. 247(2), 119–136 (2012).
3. W. Y. Oh, et.al., “Ultrahigh-resolution full-field optical coherence
microscopy using InGaAs camera,”Opt. Exp. 14 (2) 726-735(2006).

Na Huang, Lei Xi, Univ. of Electronic Science andTechnology of China (China)
Zebrafish is a top vertebrate model to study developmental
biology and genetics, and it is becoming increasingly popularfor studying human diseases due to its high genome similarity
to that of humans and the optical transparency in embryonicstages. However, it becomes difficult for pure optical imaging
techniques to volumetric visualize the internal organs andstructures of wild-type zebrafish in juvenile and adult stages
with excellent resolution and penetration depth. Even with theestablishment of mutant lines which remain transparent over thelife cycle, it is still a challenge for pure optical imaging modalities

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10024-141, Session Post

Development of an automatic 3D footscanner for customer shoe
Ameng Li, Jiping Guo, Jiping Yu, Shenzhen Academyof Metrology and Quality Inspection (China); Yong Yao,

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
Harbin Institute of Technology Shenzhen Graduate School(China)Shoes are used by everyone, a pair of shoes is very important.
However, due to the existing shoe manufacturers are basicallylimited number of preset shoe size and type, so it is not suitablefor everyone. To solve the above problem, we propose an
automatic foot three-dimensional digital scanner measurement
system. We use the stereoscopic digital cameras with digital
speckle projection, which can quickly obtain single 3d data. We
use a multi-node scanners setup, which can get the complete
three-dimensional data of the foot. We use post-processing
algorithm, which characteristic parameters of the foot for custom
shoes. Our system parameters are: scanning time 30s, scanning
accuracy 0.1mm and automated without user interaction. Our
equipment dimensions: 1200mm X 500mm X 300mm, can beeasily installed in the store. Our system has been widely installed
and used.

10024-142, Session Post

Temporal evolution of liquid-assisted hardbio-tissue ablation with infrared pulsed
lasers under a liquid environment
Faner Chen, Xianzeng Zhang, Fujian Normal Univ. (China)
Liquid-assisted hard bio-tissue ablation with the applicationof infrared pulsed laser takes advantage in precision andcompatibility than others in traditional surgery. The objective of
this study was to monitor the dynamic process of the cavitation
bubble induced by Ho:YAG laser under water environments andidentify the opening time of channel formation between thefiber tip to the target tissue surface. A free-running Ho:YAG laser
was used in the experiment. The wavelength was 2.1 ?m with apulse duration of 350us and pulse energy varied from 500mJ
to 3000mJ. The high-speed camera(PCO.dimax, Germany,
PCO) applied to monitor the whole ablation process was setting
at a frame rate of 60000 frames/s. The results showed thatthe cavitation bubble induced by laser energy experienced aoscillation process including occurrence, expansion, contraction
and subsequent collapse. A channel connected the fiber tip andtarget tissue surface was formed during the dynamic process
and allowed the pulse energy transmitted through the channel
with a relative low absorption and directly interacted with thetarget tissue. The beginning time of channel formation, as wellas the duration of channel opening, as a function of incident
laser energy and water layer thickness were also presented. A
micro-explosion was observed near the tissue surface during the
bubble collapse, which may help to produce a clean cut , reduce
the thermal injury and improve the morphology of ablation crater.
The results in the study will contribute to the interpretation ofliquid-assisted hard tissue ablation.

10024-143, Session Post

A comparative study of metabolicstate of stem cells during osteogenic
and adipogenic differentiations via
fluorescence lifetime imaging microscopy
Sandeep Chakraborty, Meng-Hsin Ou, Jean-Cheng Kuo,
Arthur E. Chiou, National Yang-Ming Univ. (Taiwan)
Cellular metabolic state can serve as a biomarker to indicate
the proliferation efficiency, and differentiation potential of stem
cells into other specialized cell lineages. In this study, twophoton fluorescence lifetime imaging microscopy (2P-FLIM)1
was applied to determine the fluorescence lifetime and theamounts of the auto-fluorescent metabolic co-factor reduced

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nicotinamide adenine dinucleotide (NADH) to elucidate thecellular metabolism of human mesenchymal stem cells (hMSCs)
in adipogenic and osteogenic differentiation processes. 2P-FLIM
provides the free to protein-bound NADH ratio which can serveas the indicator of cellular metabolic state.2 We measured NADH
fluorescence lifetime at 0, 7, and 14 days after hMSCs were
induced for both adipogenesis and osteogenesis. The average
fluorescence lifetime increased significantly at 14 day (p < 0.05)
in adipogenic differentiation while no such increase was observedin osteogenic differentiations. However, the ratio of free toprotein-bound NADH ratio decreased significantly in 7-days (p< 0.05) and 14-days (p < 0.005) in osteogenic differentiations.
In contrast, in the case of adipogenic differentiations, the free
to protein bound NADH ratio did not vary in 7 days, but showedvariance comparable to osteogenic differentiations in 14 days.
Thus, our preliminary results indicated a higher metabolic rate
in both osteogenic and adipogenic differentiation processes,
but a faster metabolic change in osteogenesis as compared toadipogenesis. This approach may be further utilized to study
proliferation efficiency and differentiation potential of stem cells
into other specialized cell lineages.
References
1. W. Becker, “Fluorescence lifetime imaging-techniques andapplications,” J. Microsc. 247(2), 119-136 (2012).
2. A. A. Heikal, “Intracellular coenzymes as natural biomarkers formetabolic activities and mitochondrial anomalies,” Biomark. Med.
4(2), 241-263 (2010).

10024-144, Session Post

Effect of femtosecond laser ablation on
Ca2+ release in the dorsal root ganglion
neurons
Liqin Zheng, Fujian Normal Univ. (China)
The Ca2+ is a ubiquitous second messenger that is responsible
for regulating a wide range of cellular and biological processes,
including cell proliferation and cell death, gene expression,muscle contraction and neurotransmission. The concentration offree intracellular Ca2+ is modulated by the balance between thecytosol and intracellular Ca2+ stores (such as the endoplasmic
reticulum and mitochondria), and the extracellular fluid. The
objective of this study was to assess if femtosecond laser
ablation could affect the intracellular Ca2+ release in dorsal root
ganglion neurons in vitro using confocal microscopy combinedwith special fluorescence probe Fluo-4/AM. The results showedthat relative fluorescence intensity increased significantly after
the axons of DRG neurons was performed with femtosecond laser
ablation. It demonstrated that femtosecond laser ablation could
enhance the intracellular Ca2+ release in the sensory neurons
and might be used to treat pain by modulating intracellular Ca2+
release in DRG neurons.

10024-145, Session Post

Saliva surface-enhanced Raman
spectroscopy for noninvasive opticaldetection of nasopharyngeal cancer
Xueliang Lin, Duo Lin, Zhihong Xu, Xiaosong Ge, Wei
Huang, Fujian Normal Univ. (China)
The early cancer detection is of great significance to increase thepatient’s survival rate and reduce the risk of cancer development.
Surface enhanced Raman spectroscopy (SERS) technique is a
rapid, convenient, non-destructive optical detection method, it
can provide a characteristic “ fingerprint ” information of target
substances, and even achieve single molecule detection. Its#PhotonicsAsia

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
ultra-high detection sensitivity has made it become one of themost potential biochemical detection methods. Saliva, a multiconstituent oral fluid, contains the bio-markers which is capableof reflecting the systemic health condition of human, showing
promising potential as a effect medium for disease monitoring.
Compared with the serum samples, the collection and processingof saliva is safer, more convenient and noninvasive. Thus, saliva
test is becoming the hotspot issues of the noninvasive cancer
research field. This review highlights and discusses current
application progress within the field of SERS saliva test incancer detection. Meanwhile, our guoup’s primary research on
noninvasive differentiation of nasopharyngeal cancer, normal andrhinitis groups using saliva-SERS method is introduced.

single point. In FF-SS-OCT, the motion of the sample during theacquisition can degrade the image quality significantly comparedto the point scanning OCT. The motion distorts the interference
fringe pattern. Even a small motion can be amplified significantly,
which is affected by the A-line acquisition rate and the frequencyof the motion in FF-SS-OCT acquisition. The motion leads tophase changes on interference pattern while sweeping the
wavelengths, thus the motion can be measured by applying
time-frequency analysis on the A-line data. We compensated theimage degradations by correcting the motion-induced phaseshift. Here, we present a system integration of FF-SS-OCT withsurgical microscope. Also, we present an algorithm to measure
and compensate the sample motion.

10024-146, Session Post

10024-148, Session Post

The effect of axial ligands on the quantum
yield of singlet oxygen of new silicon
phthalocyanine

High-resolution three-dimensional integral
imaging using Fourier ptychography

Zhe Chen, Minjiang Teachers College (China); Zhenzhen
Chen, Dongdong Ma, Sujuan Pan, Yiru Peng, Fujian Normal
Univ. (China)
Phthalocyanines (Pcs) are regarded as one of the importantorganic materials. Pcs have attracted considerable attention
over the last decades for their applications in material science.
They have been used in electro-optical devices, solar cells,
liquid crystals, optical data storage, electrochromic display, andphotodynamic therapy (PDT). However, many applications are
restrained by their limited solubility in common organic solvents
and water. Moreover, because of the π–π interaction between
planar aromatic structures, Pcs have a strong tendency to form
insoluble aggregates. Aggregation is an unfavorable propertyof Pcs since it can reduce the possibility of generation singlet
oxygen quantum yield, leading to lower their PDT effecicy.
In this paper, we designed and synthesized a novel series ofaxially di-substituents silicon phthalocyanines with different
electron-donating or electron withdrawing properties. The effectof axially substituent groups on the quantum yield of singlet
oxygen of the phthalocyanine were using the chemical capture
method, the ability to take the measurement of absorbance at
412 nm DPBF change in intensity is measured to generate singlet
oxygen. These complexes singlet oxygen quantum yields are
high, sodium dodecylbenzenesulfonate axially substituted silicon
phthalocyanine singlet oxygen quantum yield higher than othercompounds.

Leilei zhang, Juan Zhang, Muyang Zhang, Xing Zhao,
Yanmei Liang, Nankai Univ. (China)
Integral imaging is a promising technology for three dimensional(3D) imaging in which depth information was recorded inimage arrays. For some applications, such as guided surgery,micro-3D biological imaging, reconstructed images with highresolution were demanded. The quality of reconstructed images
significantly depended on the resolution of the multi-view
elemental images ?EIs?. Low-resolution EIs lead to the mismatchof the corresponding imaging points (CIPs) and decrease theprecision of reconstructed images.
Fourier ptychography (FP) is a recently developed superresolution technique which shares its roots with ptychography.
FP is the improvement of the aperture synthesis technique andthe phase retrieval technique, which acquires image arrays bymulti-angle illumination and reconstructs a high resolution image
in the frequency domain.
In this paper, we report an integral imaging scheme by exploringa LED array to provide multi-angle illumination and by using
a lens array to generate the image array. FP procedure was
firstly carried out to recover a super-resolution integral image,then phase matching method was used to gain CIPs, and finallytriangulation was used to analyze all CIPs in the integral image
and reconstruct the 3D scene. Simulated experiments were donefor 3D objects, where a 5*5 lens array and a 15*15 LED array wereadopted. The reconstructed results proved this method could
obtain high-resolution and more precise 3D images.

10024-147, Session Post

10024-150, Session Post

Motion compensation of full-field sweptsource optical coherence tomography
integrated with surgical microscope

Photo-induced electron transfer between
benzyloxy dendrimer phthalocyanine andbenzoquinone

Chang-Soo Kim, Hyeong Soo Nam, Hanyang Univ.
(Korea, Republic of); Hyunki Lee, Hong Ki Kim, Koh
Young Technology, Inc. (Korea, Republic of); Hongki Yoo,
Hanyang Univ. (Korea, Republic of)

Yiru Peng, Tiantian Zhang, Dongdong Ma, Sujuan Pan,
Shijun Wu, Yufeng Jiang, Di Zeng, Hongqing Yang, Fujian
Normal Univ. (China)

Optical Coherence Tomography (OCT) is a non-invasive opticalimaging method that shows cross-sectional images of biologicaltissue. On the other hand, surgeons examine the surgicalsite in detail using the surgical microscopes during surgery.
Combination of these two technologies would enable to image
the microscopic surface and the tomographic structures ofsurgical site at the same time. Full-field swept-source OCT(FF-SS-OCT) can achieve high-speed three-dimensional
volumetric imaging because it does not need a beam scannerthat is required in a point scanning OCT. However, acquisition
time for A-line is much longer than the point scanning OCT for
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Photo-induced electron transfer (PET) is an important andfundamental process in natural photo-synthesis. To mimic suchinteresting PET process, a suitable donor and acceptor couple
were properly chosen. Dendrimer phthalocyanines and theirderivatives have emerged as promising materials for artificial
photosynthesis systems. In this paper, the electron transfer
between the light harvest dendrimer phthalocyanine (donor)
and the 1,4-benzoquinone (acceptor) was studied by UV/Vis
and fluorescence spectroscopic methods. It was found thatphthalocyanine fluorescence quenching by BQ is via excitedstate electron transfer, from the phthalocyanine to the BQ.
The results show that the fluorescence emission of thesewww.spie.org/pa·

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
dendritic phthalocyanines could be greatly quenched by BQ
upon excitation at 610 nm. The Stern–Volmer constant (KSV) of
electron transfer is calculated. Our study suggests that these
dendritic phthalocyanines are an effective new electron donor
and transmission complex and could be used as a potential
artificial photosynthesis system.

10024-151, Session Post

Design and fabrication of common path
OCT probe with extended depth-of-focus
Jingchao Xing, JunYoung Kim, Hongki Yoo, Hanyang Univ.
(Korea, Republic of)
Optical coherence tomography (OCT) acquires three-dimensional
microstructure of biological samples. Using fiber optic probe,
minimally invasive imaging for hollow organs or deep tissues
is possible. However, using optical fibers in OCT is associatedwith several challenges. First, the path length of a reference arm
and a sample arm should be matched exactly. Any mismatch on
optical fiber length between two arms may lead to a dispersion,
which can reduce sensitivity and axial resolution. Second, thepolarization states of the signal within the fibers need to becontrolled in order to avoid polarization mismatch, which alsodegrades sensitivity. In order to avoid these problems, common
path OCT probes which embeds reference arm in the sample
arm, have been proposed. Here, we present a common path
OCT probe by utilizing a custom designed prism. This prism hasa beam split coating on one side, and the other side is coatedwith an internal reflecting aluminum to generate the reference
signal. To fabricate a common path probe, we aligned this prismat the distal end of an endoscopic imaging probe. Additionally,
to improve the depth of focus (DOF) and lateral resolution ofthis common path probe, we applied a binary phase spatial filter(BPSF) in this probe. The simulation analysis shows that theprobe with the BPSF extended the DOF by a factor of 2.67 from
72 ?m to 192.2 ?m. We tested the performance of this common
path probe by imaging 3M tape and micro-beads phantom. We
anticipate that the common path probe with extended DOF
might be used in various in vivo studies, such as cardiovasculardisease and esophageal disease.

10024-152, Session Post

10024-154, Session Post

Analysis of human biofluids with different
concentrations by Raman spectroscopy
methodDmitry N. Artemyev, Ivan A. Bratchenko, Yulia A.
Khristoforova, Anastasia A. Lykina, Oleg O. Myakinin,
Samara State Aerospace Univ. (Russian Federation);
Tatyana P. Kuzmina, Igor L. Davydkin, Samara State
Medical Univ. (Russian Federation); Valery P. Zakharov,
Samara State Aerospace Univ. (Russian Federation)
Changes in the biofluids (blood plasma, whole blood, protein
fractions) concentration and is among the most important criteria
for early diagnosis and assessment of the oncohematologicaldiseases progression. There is a significant interest in opticalmeasurement that would permit simultaneous analysis of multiple
components in whole blood without the need for conventional
sample processing, such as centrifuging and reagents adding.
The major challenge in an analysis of whole blood samples liesin the presence of numerous low-concentration components.
This work is devoted to study the possibility of plasma proteins(human serum albumin, globulin) concentration control using
Raman spectroscopy (RS) setup. The blood proteins and whole
blood were studied in this research.
Raman spectra were measured by integrated Raman setup.
The setup comprises of thermally stabilized diode laser LML785.0RB-04 (785 nm, 200 mW), commercial Raman probe andspectrograph Shamrock SR-500i-D1-R with deep cooling digital
camera Andor iDus DU416A-LDC-DD with 0.05 nm resolution.
Digital camera was air-cooled up to -70ºC. The acquisition
time was 60 seconds for signal registration from biofluids.
Biofluid samples were located in the aluminium cuvette withdifferent reflector shape. Pure Raman spectrum was achieved by
autofluorescence removal from raw data signal using polynomial
approximation method.
Current research was associated with the determination ofabnormal protein concentrations values in whole blood andblood plasma by Raman spectroscopy. For data processing PLS
regression and PCA were utilized. The root mean squared error(RMSE) and squared correlation coefficient (R2) were calculated
for blood compounds concentrations study.

Study on nasopharyngeal cancer
tissue using surface-enhanced Raman
spectroscopy

10024-155, Session Post

Xiaosong Ge, Zhihong Xu, Xueliang Lin, Wei Huang, Duo
Lin, Fujian Normal Univ. (China)

Shulian Wu, Liangjun Hu, Hui Li, Fujian Normal Univ.
(China)Surface-enhanced Raman spectroscopy (SERS) can provide
detailed molecular structure and composition information,and has demonstrated great potential in biomedical filed.
This spectroscopy technology has become one of the mostimportant optical techniques in the early diagnosis of cancer.
Nasopharyngeal cancer (NPC) is a malignant neoplasm arisingin the nasopharyngeal epithelial lining, which has relatively highincidence and death rate in Southeast Asia and southern China.
This paper reviews the current progress of SERS in the field ofcancer diagnostics, including gastric cancer, colorectal cancer,
cervical cancer and nasopharyngeal cancer. In addition to above
researches, we recently develop an novel NPC detection method
based on tissue section using SERS, and obtain primary results.
The proposed method has promising potential for the detectionof nasopharyngeal carcinoma.

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Quantitative analysis on texture of skindamaged by excessive ultraviolet radiation

Texture feature is significant internal visual features of images. It
includes the arrangement of surface structure and the order ofthe organization internal. The texture feature reflects the qualityof images with phenomenon recurring visual characteristics.
In our study, the images during the process of skin damage
irradiated by excessive ultraviolet radiation in the mouse weremonitored by multiphoton microscopy in vivo. A box-counting
algorithm and gray lever co-occurrence matrix were applied
to determine the collagen texture feature in order to evaluate
the skin damage in different irradiated doses. Then, the neuralnetwork tool was applied to training the texture feature indifferent statues obtaining from skin imaging. The damage
states were distinguished by the NNtool model. The results will
help us to further understand the characters of skin damage
from texture feature, and then the results will demonstrated thatthe distinguish of skin damage from texture with an objective
method.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-156, Session Postand evidence of extensive cell disruption and lysis was foundunder SEM.

Monitoring oxygen saturation and blood
perfusion changes in port wine stains
during vascular targeted photodynamic
therapy

Conclusions: The results demonstrated that benzylidene
cyclopentanone photosensitizer?P2?is a potential photosensitizer
to kill H. pylori.

10024-159, Session Post

Defu Chen, Beijing Institute of Technology (China); Ying
Wang, Ying Gu, Chinese PLA General Hospital (China)
Vascular targeted photodynamic therapy (V-PDT) is believed to
be an effective treatment modality for port wine stains (PWS).
V-PDT uses the light source to activate the photosensitizer which
reacts with molecular oxygen to generate the reactive oxygen
species that can selectively damage the dilated and malformed
blood vessels in PWS. The V-PDT efficacy is largely dependent on
the blood oxygen and photosensitizer concentration levels, which
can be affected by blood perfusion especially for systematic
administration of photosensitizers. The objective of this study
was to investigate the changes in oxygen saturation (StO2) andblood perfusion of PWS during V-PDT. In this study, the StO2 andblood perfusion in PWS immediately before and at 3, 5, 7, 10, 15,
20 min during V-PDT were non-invasively monitored by diffuse
reflectance spectroscopy (DRS) and laser Doppler imaging (LDI),
respectively. Our results showed that there were high inter- andintra-patient heterogeneity in StO2 and blood perfusion of PWS.
Before V-PDT, blood perfusion in PWS could be larger than, or
occasionally equivalent to, that of contralateral healthy skin, butthere was no significant difference in StO2 between them. During
V-PDT, the blood perfusion in PWS first increased, then reacheda peak, followed by a slowly decrease to a relatively lower level.
There was no obvious pattern observed for the changes of StO2
in PWS during V-PDT, and no significant reductions in StO2
were observed. In conclusion, the LDI and DRS are capable ofassessing microvascular response to V-PDT.

10024-158, Session Post

To break the optical diffraction limit, to achieve an improved
resolution, based on studies of single molecule microscopy inthe field of traditional and the modern domain, we develop
the method of continuous zoom multiple configuration, andthe establishment of a micro lens array and core optics as themain component in a system to attempt to establish model by
novel principle on resonance energy transfer and high accuracy
localization by which between the principle and applicationof molecular resonance, as well as single molecule positioning
technology, the system resolution can be improved with alevel of a few nanometers. A comparative study on traditional
design methods and their advantages and disadvantages of theimplementation mechanisms can demonstrate that the dialectical
relationship and their balance is important, among Merit function,
Optimization algorithms and Model parameterization. The effectof system evaluated criterion that Modulation Transfer Function(Modulation Transfer Function, the MTF), Energy concentration(Radial Energy Analysis, REA), diffusion (Spot Diagram, RMS)
and other aspects and other qualitative criteria can support
our arguments. And the results can be used as basis for thedevelopment of new products.

Precision-enhanced fluorescence lifetime
imaging method

Ying Wang, Ying Gu M.D., Leili Wang, Zulin Ye, Chinese
PLA General Hospital (China)
Background: Antibiotics combination therapies are therecoginized key approach to prevent H. pylori infection relateddiseases, such as peptic ulcer, gastric cancer, et al. With thewidespread prolonged use of broad-spectrum antibiotics,
antibiotic resistance rate of H. pylori increased and its eradication
rates decreased notablely. Alternative monotherapy drug or
method to kill H. pylori are needed to be explored. Photodynamic
therapy (PDT) is a new anti-tumor and antibacterial technology.
It has the potential to be a new strategy for the treatment of
H. pylori infection in people at high risk of gastric cancer. In
this study, the antimicrobial activity of a cationic benzylidene
cyclopentanone photosensitizer (P2) against H. pylori wasevaluated.
Methods: Suspensions Helicobacter pylori were incubated with
P2 concentrations (2.5, 5, 10 and 25 ?M) for 30 min followed by
532-nm laser irradiation. Immediately after PDT, the viability of H.
pylori was assayed by CFU counting. All the process was carriedout at 37 °C in a standard microaerobic atmosphere within amicroaerobic bag. The ultrastructure change of H. pylori induced
by PDT was observed under scanning electron microscope (SEM).
Results: The bactericidal effect of PDT increased with theconcentration of P2 increasing. The CFU count of H. pylori
drcreased 2 log, 4 log, 5 log and 5 log at different concentrationof P2(2.5, 5, 10 and 25?M respectively). Loss of structural integrity

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Hua Liu, Luoyang Institute of Electro-Optical Equipment(China)10024-160, Session Post

In vitro photodynamic antimicrobialactivity of cationic benzylidene
cyclopentanone Photosensitizer (P2)against Helicobacter pylori

162

Solutions to improve multiple
configuration system resolution in imaging
sensors·

Hyeong Soo Nam, Min Woo Lee, Hanyang Univ. (Korea,
Republic of); Tae Shik Kim, Woo Jae Kang, KAIST (Korea,
Republic of); Jin Won Kim, Korea Univ. (Korea, Republicof); Wang-Yuhl Oh, KAIST (Korea, Republic of); Hongki
Yoo, Hanyang Univ. (Korea, Republic of)Tissue auto-fluorescence can be used for imaging specificcomponents in biological sample. However, fluorescenceintensity is prone to be distorted because of the difficulty tomeasure absolute value. Accordingly, fluorescence lifetime canbe an alternative strategy and it has been widely used due toits benefit of insensitivity to the intensity. In approaches formeasurements of lifetime using pulse sampling, fluorescentdecay signals are recovered by the deconvolution process of
instrumental response function (IRF). Unfortunately, in theseapproaches to estimate the IRF prior to measurement of a
substance, jitter noise of the pulsed laser and the digitizer may
degrade the precision. Averaging can be helpful for the problem,
but it lowers acquisition speed. In this context, we present a
method for precision enhancement for high speed applicationof fluorescence lifetime imaging system based on simultaneous
acquisition of IRF. It was accomplished by multiple detection
fibers with different lengths to measure signals of IRF andfluorescences of each channel, respectively. This simultaneous
acquisition is insensitive to the jitter noise, thus it can improve
precision of measurement of lifetime. It was validated by tissue
phantoms and ex vivo rabbit atherosclerotic tissue, showing anenhanced precision under 50 picosecond without averaging

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
and correspondence between spectrally-resolved lifetimes andhistopathological sections of tissues, respectively. This strategy
may enable to acquire a molecular information of a biologicalsample in vivo in virtue of its advantage to the availability forhigh speed.

10024-164, Session Post

10024-162, Session Post

Xiao Peng, Yihua Zhao, Shuyi Yuan, Shaozhuang Yang,
Wei Yan, Ming Zhu, Jun Song, Junle Qu, Shenzhen Univ.
(China)Automatic density artefact removal
method for structured illumination
microscopy data
Jie Peng, Anan Li, Huazhong Univ. of Science andTechnology (China); Qingming Luo, Britton Chance Ctr. for
Biomedical Photonics (China); Hui Gong, Huazhong Univ.
of Science and Technology (China)
The reconstruction of exquisite neural network from microscopic
image set is the base of understanding the mechanism of brain.
Structured illumination microscopy (SIM) is one of the imaging
instruments to obtain 3-D image set from a large sample,
e.g. mouse brain. However, to perform high speed for dataacquisition, the RAW tile images from SIM have non-uniform
intensity and contrast, therefore we have to correct the tile
images before structure analysis and visualization of brain.
The correction can be mainly splat into two steps, eliminating
the grid stripes within one coronal layer and uniforming thebrightness values in coronal sequence along the axial direction.
In the first step, polynomials is used to fitting the meanvalue of one coronal layer along transverse and longitudinal
respectively, and the correction factors got from fitting result
are used to remove the grid dark lines. In the second step, Thebackground’s mean value within mouse brain is extracted withthreshold and morphology method, then combined with a preset
brightness value parameter, the correction parameter for every
layer’s brightness is obtained. The automatic method has been
implemented on both single workstation and cluster which
provides a high quality and efficiency data correction approach.

10024-163, Session Post

Tuning the red emission of NaYF4:Yb/Erthrough core-shell nanostructure
Yihua Zhao, Xiao Peng, Shuyi Yuan, Shaozhuang Yang,
Wei Yan, Ming Zhu, Jun Song, Junle Qu, Shenzhen Univ.
(China)Lanthanide doped upconversion nanoparticles (UCNPs) havereceived much attention due to their potential application in
optical devices, sensing, and therapeutics. Compared withconventional organic dyes and quantum dots, the UCNPs
possess following advantages: near-infrared (NIR) excitation, lowcytotoxicity, weak autofluorescence, high chemical stability, andlow photo-bleaching. However, the commonly studied lanthnide
activators such as Er3+ and Tm3+ contain abundant metastable
excited states, and the dominant emission usually does not lies
within the “tissue optical window” (spanning approximately from
650 to 1200 nm). Here, we present a core-shell-shell approachto tune the color emission of typical NaYF4:Yb/Er system. By
embeding NaYF4: Yb/Er between NaYF4 layers, the energy
migration induced energy loss to the crystal lattice in NaYF4:Yb/
Er can be effectively suppressed. Moreover, the cross relaxation
effect can be adopted to induce red color emission, without“concentration quenching effect. The resulting UCNPs show
low cytotoxicity, according to HeLa cell-based MTT assay. In
conclution, we show a novel core-shell-shell approach to boost
both the red color emission and the of luminescence efficiency oftypical NaYF4:Yb/Er system.

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Immunomodulatory effects of NaYbF4:Erbased core-shell-shell upconversion
nanoparticles on RAW264.7 cells

Recently, upconversion nanoparticles (UCNPs) have been
proved to contain excellent optical properties. They haveplayed more and more important role in biological and medical
applications, including imaging and photo-therapy. Therefore,
it is essential to reveal a comprehensive understanding of thecytotoxicity and biocompatibility of the UCNPs, especially theirimmunomodulatory effects [1-3]. In this study, a series of ~30
nm NaYbF4:Er-based core-shell-shell UCNPs, in which size
effect could be harnessed to enhance 654 nm emission, weresynthesized using Ostwald-Ripening strategy. Moreover, thesurfaces of resulting UCNPs were modified with polyacrylic acid
(PAA). In the following, both the bare UCNPs and the PAAmodified NCNPs were applied onto the mouse macrophage
Raw264.7 cells for several biological tests to figure out theirpotential cytotoxicity, including cell viability assay and apoptosis
test. Furthermore, the secretion of TNF-? and IL-6 by Raw264.7
cells with the addition of the UCNPs were tested to analyze theirimmunomodulatory effects. In conclusion, both the bare and the
PAA-modified UCNPs contain low cytotoxicity and stimulatory
effects on immune cells, suggesting promising biologicalapplications.

10024-165, Session Post

Hyperspectral imaging in the visible range
for in vivo skin cancer differentiation
Larisa A. Zherdeva, Ivan A. Bratchenko, Oleg O. Myakinin,
Samara State Aerospace Univ. (Russian Federation);
Alexander A. Moryatov, Sergey V. Kozlov, Samara State
Medical Univ. (Russian Federation); Valery P. Zakharov,
Samara State Aerospace Univ. (Russian Federation)
Study results of hyperspectral imaging (HSI) for in vivo
visualization of skin neoplasms are presented. 53 patients ofoncological center are diagnosed for determining a type of skinpathology by HSI method. Hyperspectral results are comparedwith the histological analysis of a patient samples. The in vivo
tissues diagnostics are approved by the ethical committee ofSamara State Medical University.
The following types of skin neoplasms are investigated:melanoma, basal cell carcinoma, pigmented nevi and benign withdifferent stages of neoplasm growth (I - IV types). The system of
HSI can display the images with spectral resolution of up to 2.1
nm in the range of 450-750 nm and provides the capability toobtain images at a rate of 3 frames per second with a resolutionof 1360x1024 pxl (maximum increase in scanning area is 7x7cm). Frame at each wavelength is stabilized in a time intervalof scanning relative to a selected stationary frame due to adisplacement of the scanning area related with a spontaneous
macro-movements of the patient. The obtained data has beenprocessed in MATLAB R2014a. Backscattering spectra arestimulated by white LED source. Background illumination has
been calculated from approximated spectral images of thesample as a distribution function of the source field.
As a result, the index of optical densities amounts in maximumof hemoglobin and melanin absorption ranges (530-600 and
600-670 nm respectively) and the distribution of index values
in the entire neoplasm area allows to differentiate the type of
pathological tissues.

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-166, Session Post

10024-168, Session Post

Classification for skin cancer using theintensity-based texture-based and fractalbased features with optical coherence
tomography

Facile synthesis of Gd-Cu-In-S/ZnS
bimodal quantum dots with optimized
properties for tumor targeted
fluorescence/MR in vivo imaging

Wei Gao, Ningbo Univ. of Technology (China); Oleg O.
Myakinin, Ivan A. Bratchenko, Dmitry V. Kornilin, Valery
P. Zakharov, Samara State Aerospace Univ. (RussianFederation)

Bingbo Zhang, Weitao Yang, Tongji Univ. (China)

Optical coherence tomography (OCT) is employed in the
diagnosis of skin cancer. Particularly, quantitative image features
extracted from OCT images might be used as indicators toclassify the skin tumors. In the present paper, we investigatedintensity-based, texture-based and fractal-based features forautomatically classifying the melanomas, basal cell carcinomas
and pigment nevi. Our results suggest that the selected
quantitative image features of OCT images could provide useful
information to differentiate basal cell carcinomas and pigment
nevi from the melanomas. Further research is warranted todetermine how this approach may be used to improve theclassification of skin tumors.

10024-167, Session Post

Skin cancer texture analysis of OCT
images based on Haralick, fractal
dimension, Markov random field features,and the complex directional field features
Dmitry S. Raupov, Oleg O. Myakinin, Ivan A. Bratchenko,
Valery P. Zakharov, Samara State Aerospace Univ. (RussianFederation); Alexander G. Khramov, Samara Aerospace
Univ. (Russian Federation)
In this paper, we propose a report about our examining of
the validity of OCT in identifying changes using a skin cancer
texture analysis compiled from Haralick texture features, fractal
dimension, Markov random field method and the complex
directional features from different tissues. Described features
have been used to detect specific spatial characteristics, which
can differentiate healthy tissue from diverse skin cancers incross-section OCT images (B- and/or C-scans). In this work, weused an interval type-II fuzzy anisotropic diffusion algorithm
for speckle noise reduction in OCT images. The Haralick texture
features as contrast, correlation, energy, and homogeneity havebeen calculated in various directions. A box-counting method is
performed to evaluate fractal dimension of skin probes. Markov
random field have been used for the quality enhancing of theclassifying. Additionally, we used the complex directional fieldcalculated by the local gradient methodology to increase of
the assessment quality of the diagnosis method. Our results
demonstrate that these texture features may present helpful
information to discriminate tumor from healthy tissue. The
experimental data set contains 166 OCT-images with normal skinand tumors as Basal Cell Carcinoma (BCC), Malignant Melanoma(MM) and Nevus. All images were acquired from our laboratory
SD-OCT setup based on broadband light source, delivering an
output power of 20 mW at the central wavelength of 840 nmwith a bandwidth of 25 nm. We obtained sensitivity about 96%
and specificity about 99% for a task of discrimination between
MM and Nevus.

Dual-modal imaging techniques have gained intense attentions
for their potential role in the dawning era of tumor early accurate
diagnosis. Chelate-free robust dual-modal imaging nanoprobeswith high efficiency and low toxicity are of essential importancefor tumor targeted dual-modal in vivo imaging. It’s still a crucial
issue to endow Cd-free dual-modal nanoprobes with brightfluorescence as well as high relaxivity. Herein, a facile synthetic
strategy was developed to prepare Gd-doped CuInS/ZnS bimodal
quantum dots (GCIS/ZnS, BQDs) with optimized properties. The
fluorescent properties of the GCIS/ZnS BQDs can be thoroughly
optimized by varying reaction temperature, aging time and ZnS
coating. The amount of Gd precursor can be well controlled torealize the optimized balance between the MR relaxivity andoptical properties. The obtained hydrophobic GCIS/ZnS BQDs
were surface engineered into aqueous phase with PEGylated
dextran-stearyl acid polymeric lipid vesicles (PEG-DS PLVs).
Upon the phase transfer, the hydrophilic GCIS/ZnS@PLVs
exhibited pronounced near infrared fluorescence as well as highlongitudinal relaxivity (r1=9.45 mM-1•S-1) in water with good
colloidal stability. In vivo tumor-bearing animal experiments
further verified GCIS/ZnS@PLVs could achieve tumor-targeted
MR/fluorescence dual-modal imaging. No toxicity was observedin the in vivo and ex vivo experiments. The GCIS/ZnS@PLVs
present great potential as bimodal imaging contrast agents fortumor diagnosis.

10024-169, Session Post

Hyperspectral imaging for skin cancer
diagnosis
Lixin Liu, Xidian Univ. (China); Zhigang Zhao, Junle Qu,
Shenzhen Univ. (China)
Hyperspectral imaging (HSI) technology is an emerging modalitythat combines the advantages of both imaging and spectroscopy
in one device. Although HSI originated for remote sensing, it has
recently developed as a powerful process analytical tool for nondestructive medical imaging and diagnostics with the advantageof acquiring two-dimensional images across a wide range ofelectromagnetic spectrum. During the progression of disease,
the absorption, fluorescence, and scattering characteristics oftissue may change. Therefore, the reflected, fluorescent, andtransmitted light from tissue captured by HSI carries quantitative
diagnostic information about tissue pathology. In this study,
we set up a hyperspectral imaging system for the quantitative
measurement and imaging the normal and cancer skin tissue withhigh spatial and spectral resolution. The approach proposed here
may have potential applications in early disease detection anddiagnosis.

10024-170, Session Post

Principal component prediction in
cartilages by infrared imaging and support
vector machine
Jian-Hua Yin, Nanjing Univ. of Aeronautics andAstronautics (China)
Fourier transform infrared imaging (FTIRI) combined Support

164

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
Vector Machine (SVM) was used to detect the depth-dependent
content variations of principal components, collagen andproteoglycan (PG), in Bovine nasal cartilage (BNC) and articularcartilages. The cartilages were sectioned at 10 ?m thick and driedin air for a couple of hours, and then imaged at 6.25 ?m pixelsize in FTIRI. The infrared spectra extracted from FTIR images
were imported into SVM program to predict the quantitative
distributions of both collagen and proteoglycan in BNC and(osteoarthritic and healthy) cartilage sections. The principal
components distributed homogenously in BNC. The depth
dependence of PG content was obtained and showed obvious
difference between the cartilage sections of osteoarthritis
and health, which is in well agreement with our previous PLS
prediction. Relative to health, PG content decreases clearly in theosteoarthritis. This observation demonstrates that this combined
imaging and SVM approach could be used as a sensitive tool toaccurately predict and resolve the concentration distributions ofmacromolecules in biological tissues.

10024-171, Session Post

Implementation by laser micromachiningof a grid-based visual aid for enhanced
diagnostic microscopy in PAP test
cytological screening
Christos Riziotis, National Hellenic Research Foundation(Greece); Evangelos Tsiambas, 401 General Military
Hospital (Greece) and National and Capodistrian Univ. ofAthens (Greece) and mycolab Diagnostic Labs. (Greece)
Cervical screening based on Papanicolaou (PAP) test has been
proved to be an efficient practice for preventing cervico-vaginal
cancer in high risk Human Papilloma Virus (HPV) infected women.
Introduction of liquid based process, automatization and digital
image analysis has led to a more reliable diagnosis compared toconventional management of the slides. However, microscopy
based diagnosis in Cytology is characterized by a variety ofparameters, including specimens’ adequacy, inhomogeneous
cell density, fixing/staining procedure quality, observation
ability and subjectivity in diagnosis. The paper introduces areal-time screening platform for improved diagnosis in PAP
test slides. The presented solution provides a spatial grid withsequentially indexed segments that can be attached to carrier
microscope slide acting as a calibration and orientation visual aid
to the cytologist during the real-time screening process. Thosegrids were implemented using an infrared femtosecond Laser
Micromachining-FLM system (1064 nm, 1?J) on commerciallyavailable borosilicate glass microscope cover slips. Abnormal
and formerly diagnosed as negative for intraepithelial lesion ormalignancy (NILM) Pap test slides (n=200) were analyzed byconventional and grid-based screening. Grid-based microscopy
led to a more reliable diagnosis compared to the conventionalby identifying an increased number of abnormal and neoplastic/
cancerous cells, and also in shorter screening time. It decreased
borderline ASCUS, AGC diagnosis, increasing LGSIL, HGSIL andin situ AdenoCa detection rates closely related with biopsy withexcellent statistical agreement. The proposed solution offers acalibration and orientation visual aid during the on-site screening
process providing significant advantages compared to expensive
digital imaging techniques.

10024-172, Session Post

Blood vessel damage correlated with
irradiance for in vivo vascular targeted
photodynamic therapy
Jinde Zhang, Tan Zou, Fujian Normal Univ. (China);

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Xiangyu Niu, Fujian Normal Univ. (China); Lisheng Lin,
Buhong Li, Fujian Normal Univ. (China)
Vascular targeted photodynamic therapy (V-PDT) has been
widely utilized for the prevention or treatment of vascular-relateddiseases, including age-related macular degeneration, port-wine
stains and prostate cancer. In order to quantitative assessment
the blood vessel damage during V-PDT, nude mice were
implanted with Titanium dorsal skin window chambers for in vivo
studies. For V-PDT treatment, various irradiances including 50,
75, 100 and 200 mW/cm2 provided by a 532 nm semiconductor
laser were performed with the same total light dose of 30 J/cm2
after the mice were intravenously injection of rose bengal for 25
mg/Kg body weight. Laser speckle imaging and microscope wereused to monitor blood flow dynamics and vessel constriction
during and after V-PDT, respectively. The results show that higher
blood perfusion rate in blood vessels generally resulted in higher
vasoconstriction. In addition, significant difference in blood vessel
damage was found between the lower irradiances (50, 75 and100 mW/cm2) and higher irradiance (200 mW/cm2). This study
suggests that the blood vessel damage induced by V-PDT is
positively correlated with irradiance, and optimized irradiance isrequired to enhance therapeutic efficiency.

10024-173, Session Post

Improving the signal-to-noise ratio in
ultrasound-modulated optical tomography
by a lock-in amplifier
Lili Zhu, Jingping Wu, Guimin Lin, Hui Li, Fujian Normal
Univ. (China)
With high spatial resolution of ultrasonic location and highsensitivity of optical detection, ultrasound-modulated optical
tomography (UOT) is a promising noninvasive biologicaltissue imaging technology. In biological tissue, the ultrasoundmodulated light signals are very weak and are overwhelmed by
the strong unmodulated light signals. It is a difficulty and key toefficiently pick out the weak modulated light from the strong
unmodulated light in UOT. Under the effect of an ultrasonicfield, the scattering light intensity presents a periodic variation
as the ultrasonic frequency changes. So the modulated lightsignals would be escape from the high unmodulated light signals,
when the modulated light signals and the ultrasonic signal areprocessed cross correlation operation by a lock-in amplifier
and without a chopper. Experimental results indicated that thesignal-to-noise ratio of UOT is significantly improved by a lockin amplifier. And the higher the repetition frequency of pulsed
ultrasonic wave, the better the signal-to-noise ratio of UOT.

10024-174, Session Post

Synthesis and application of the
reduction-sensitive drug delivery system
based on water-soluble ZnInAgS quantum
dots
Rong Zhang, Rong Zhang, China Pharmaceutical Univ.
(China)High-quality water-soluble quantum dots had been synthesized
following the one-step method. Furtherly, the impact factors on
the optical properties of quantum dots, which were the feed ratioof S/In and the reflux time, had been concerned emphatically.
By changing the reaction parameters, we made the fluorescenceemission of ZnInAgS quantum dot tunable from green to orange,
and the maximum fluorescence quantum efficiency was up
to 30%. We also carried out the cytotoxic study of ZnInAgS
QDs, compared with the commonly used fluorescent probes#PhotonicsAsia

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
such as CdTe and CdSe, ZnInAgS showed a lower cytotoxicity,which confirmed it was a potential fluorescent material in thebiomedical field. By ligand substitution effect, the dihydrolipoic acid-PEG-FA was modified to the surface of quantum dot
ZnInAgS, as a targeting fluorescent probe, the modified ZnInAgS
could be applied to early diagnosis of cancer. The results of thisstudy indicated that, as a novel composite nano fluorescentprobes, folic acid modified ZnInAgS quantum dots had superior
optical properties and good biocompatibility. Through theinteraction of folic acid and folate receptors on the tumor cell
membrane, the probe could target to the Bel-7402 tumor cellswith high expression of folate receptor, which provided a fast,
intuitive, and effective method for the detection of cell imaging,and played a catalytic role in the research of tumor early
diagnosis.

10024-177, Session Post

10024-175, Session Post

Depth-section imaging of swine kidney byspectrally-encoded microscopy
Jiuling Liao, Wanrong Gao, Nanjing Univ. of Science andTechnology (China)

Non-invasive optical detection of HBVbased on serum surface-enhanced Raman
spectroscopy
Zuci Zheng, Qiwen Wang, Cuncheng Weng, Shangyuan
Feng, Fujian Normal Univ. (China)

The kidneys are essential regulatory organs whose main function
is to regulate the balance of electrolytes in the blood, alongwith maintaining pH homeostasis. The study of the microscopic
structure of the kidney will help identify kidney diseases
associated with specific renal histology change. Spectrally
encoded microscopy (SEM) is a new reflectance microscopic
imaging technique in which a grating is used to illuminate
different positions along a line on the sample with different
wavelengths, reducing the size of system and imaging time.
The feasibility of using SEM for visualizing the morphology ofgastroesophageal biopsy samples and breast cancer specimens
at subcellular resolution has been previously demonstrated. In
this paper, a SEM device is described which is based on a superluminescent diode source and a home-built spectrometer. The
lateral resolution was measured by imaging the USAF resolution
target. The axial response curve was obtained as a reflect mirror
was scanned through the focal plane axially. In order to test thefeasibility of using SEM for depth-section imaging of an excisedswine kidney tissue, the images of the samples were acquired byscanning the sample at 10 ?m per step along the depth direction.
Architectural features of the kidney tissue could be clearlyvisualized in the SEM images, including glomeruli and bloodvessels. Results from this study suggest that SEM may be usefulfor locating regions with probabilities of disease or cancer.

An optical method of surface-enhanced Raman spectroscopy(SERS) was developed for non-invasive detection of hepatitis B
surface virus (HBV). Hepatitis B virus surface antigen (HBsAg) isan established serological marker that is routinely used for the
diagnosis of acute or chronic hepatitis B virus(HBV) infection.
Utilizing SERS to analyze blood serum for detecting HBsAg has
not been reported in previous literature. SERS measurements
were performed on two groups of serum samples: one group for
50 HBV patients and the other group for 50 healthy volunteers.
Blood serum samples are collected from healthy control subjects
and patients diagnosed with HBV. Furthermore, principal
components analysis (PCA) combined with linear discriminant
analysis (LDA) were employed to differentiate HBV patientsfrom healthy volunteer and achieved sensitivity of 80.0% andspecificity of 74.0%.This exploratory work demonstrates that
SERS serum analysis combined with PCA-LDA has tremendous
potential for the non-invasive detection of HBV.

10024-178, Session Post

Development of a new first-aid
biochemical detector
Jingfei Hu, Haiyang Liao, Shilin Su, Hao Ding, Suquan Liu,
Chongqing Univ. (China)

10024-176, Session Post

In vivo multimodal microscope integrating
photoacoustics, two-photon, and secondharmonic generation
Wei Song, Shenzhen Institute of Advanced Technology(China)Recently, we developed a novel photoacoustic microscopy(PAM) with multiple advantages including subwavelength
resolution (~300 nm at 532-nm laser illumination), reflectionmode imaging capability, and natural integration with high-speed
optical scanning mechanism, which is capable of label-freely
imaging optical absorption contrasts in vivo. In order to provide
comprehensive physiological and pathological information of
biological tissue, a multimodal microscope system is further
developed by integrating PAM with two-photon fluorescenceand second harmonic generation (SHG) into one platform. Taking
advantage of the unique imaging mechanisms of these threetechnologies, the multimodal microscope reveal complementary
optical properties simultaneously, including the optical
166

absorption, two-photon excited fluorescence, and SHG. By
imaging mouse ears, PAM visualizes microvessels based on thestrong optical absorption of inherent hemoglobin, two-photon
microscope images nicotinamide adenine dinucleotide (NADH)
and GFP-expressed neurons by acquiring the autofluorescence,and SHG resolves fine structure of collagen fibers, respectively.
The three modalities show automatic imaging registration
because they share the same laser delivery and scanningmechanisms, as well as they have comparable spatial resolution.
The reported results suggest that, by revealing complementary
tissue microstructures in vivo, this multimodal microscopy canpotentially facilitate a broad range of biomedical studies, suchas imaging of the tumor microenvironment and neurovascular
coupling.

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The traditional biochemical detector exhibits poor adaptability,
inconvenient carrying and slow detection, which can’t meetthe needs of first-aid under field condition like natural or manmade disasters etc. Therefore a scheme of first-aid biochemical
detector based on MOMES Micro Spectrometer, UV LED andPhotodiode was proposed. An optical detection structure
combined continuous spectrum sweep with fixed wavelength
measurement was designed, which adopted mobile detection
optical path consisting of Micro Spectrometer and Halogen Lamp
to detect Cl-, Cre, Glu, Hb. The UV LED and Photodiode were
designed to detect K+, CO2, Na+. According to the field diagnosis
and treatment requirements, we designed the embedded control
hardware circuit and software system, the prototype of firstaid biochemical detector was developed and the clinical trials
were conducted. Experimental results show that the sample’sabsorbance repeatability is less than 2%, the max coefficient ofvariation (CV) in the batch repeatability test of all 7 biochemicalparameters in blood samples is 4.8%, less than the clinicalrequirements 10%, the correlation coefficient (R2) in the clinicalcontrast test with AU5800 is greater than 0.98. To sum up, theprototype meets the requirements of clinical application.

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Conference 10024:
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10024-179, Session Post

10024-181, Session Post

RGD peptide conjugated-RhB probe
for detecting the expression of integrin
receptor integrin ?v?3

Retinal image quality and visual stimuli
processing by simulation of partial eye
cataract

Menglu Zhao, Yueqing Gu, China Pharmaceutical Univ.
(China)Maris Ozolinsh, Olga Danilenko, Univ. of Latvia (Latvia)

RGD peptide conjugated-RhB or cRGDyK-RhB can be used as
molecular probes.As the Integrin receptor ?v?3 is capable ofcombining with RGD peptides , when high-expression cells with
Integrin receptor avb3 incubating with RGD peptides which is
conjugated with RhB, the phenomenon that peptides probes areattached to the cell membrane integrin receptor can be detectedby the confocal microscopy.By contrast, the phenomenon is notshown in low-expression cells.Under this condition,this method
can be a fast and convenient way to detect the expression ofIntegrin receptor ?v?3 using RGD peptide conjugated with
RhB probe.Besides,the flow cytometry is also used to certain
the method.Incubating the cells with the peptide probe, mean
flourscence indensity of high-expression cells with Integrin
receptor?v?3 have significantly increased while low-expression
cells with Integrin receptor?v?3 remain the same throughcalculating .Thus,it is proved that the method that using RGD
peptide conjugated with RhB probe to detecting the expressionof Integrin receptor ?v?3 is reliable.

10024-180, Session Post

Cypate-mediated thermosensitive
nanoliposomes for NIR imaging andphoto-thermo triggered drug release
Liwei Lv, Zhihao Han, Yueqing Gu, China Pharmaceutical
Univ. (China)
The more and more excessive treatments and the resulting
serious pain the patients get in the whole period of treatment
call for precise diagnosis and effective as well as comprehensive
treatments. In this work, we developed a kind of multi-functional
photo-thermal sensitive liposomes (PTSL), by doping cypate,with the abilities of near infrared (NIR) imaging, photo-thermo
conversion and singlet oxygen generating, into hydrophobic
layer of the synthesized thermosensitive liposomes (TSL).
Based on the PTSL, a theranostic nanocomposite, DOX@PTSL
was established with doxorubicin (DOX) entrapped into thehydrophilic layer of PTSL. The physico-chemical properties werecharacterized by laser particle size analyzer, transmission electron
microscope (TEM), UV-Visable spectrophotometer, infrared
thermal imager and differential scanning calorimetry (DSC). For
cell experiments, the MTT assay was performd to study the cell
toxicities and the confocal laser scanning microscope (CLSM)
was used to observe the locating properties and dynamics of
DOX@PTSL after incubated with U87 cell lines and irradiated with
NIR laser. The biodistribution, thermal images, and therapeutic
effects of DOX@PTSL on tumor-bearing mice were investigatedin the animal experiments. The size of liposome we synthesized
is 90 to 190 nm while the phase inversion temperature falls
on 43.1°C. And importantly, the drug release can be traggered
by NIR laser, with almost all drugs entering the tumor cells’
nucleus. In general, the DOX@PTSL was demonstrated tumortargeted abilities, enhanced antitumor activities, minimal side
effects and significant improved capability to combat with free
DOX as results of the comprehensive therapeutic effectivenessof chemotherapy, thermotherapy and cypate-mediatedphotochemical internalization.

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We present a technique that allows control of visual stimuli
quality using a polymer dispersed liquid crystal (PDLC) film
placed in the optical pathway of one or both human eyes [1]. All
equipment was incorporated in a “Virtual Reality” adapter. Visual
stimuli were demonstrated on a 5’ mobile phone screen inside
adapter that allowed separation of the left and right eye visual
fields. Contrast of the retina image thus can be controlled by theimage on the phone screen and parallel to that by the AC voltage
applied to PDLC cell. Such optical pathway separation allows
to demonstrate to both eyes spatially variant images, that after
visual binocular fusion acquire their characteristic indications.
As visual stimuli we used different color (two opponents tovision – red-green in Lab color space) stimuli for left and righteyes; and with spatial content that by addition or subtraction
results as clockwise or counter clockwise slanted Gabor gratings.
We performed computer modelling of signal processing in
brain via stimuli input decomposition in luminance and color
opponency components. It revealed the dependence of thepsychophysical equilibrium point between clockwise or counterclockwise perception on eye image contrast and color saturation,and on the strength of the retinal aftereffects. Actual observer
perception experiments when one eye images were deteriorated
by artificial cataract using PDLC approved the shift of mentioned
psychophysical equilibrium point on the degree of artificial
cataract.
[1] Glass Apps, “Glass Apps, Electrochromic Glass vs. PDLC –Smart Glass Technology Comparison.” 2015. http://www.glassapps.com/electrochromic-glass

10024-182, Session Post

Dual modality In vivo imaging of rodent
fundusZhiyu Huang, Peking Univ. (China); Richard Johnson,
Friedrich-Alexander-Univ. Erlangen-Nürnberg (Germany);
Xiaoyun Jiang, Qiushi Ren, Changhui Li, Peking Univ.
(China)Confocal scanning laser ophthalmoscopy (CSLO) and opticalcoherence tomography (OCT) provide complementary
information of the animal fundus. Data acquired by CSLO have
low axial resolution but high lateral resolution providing sharp
images of the retinal structure and vessels, as well as molecularimaging. OCT is capable of creating lateral fundus scans witha high axial resolution. In this work, these two modalities werecombined into one device, to simultaneously examine therodent fundus. To improve the image quality and procedureof the experiment, a home-made contact probe for rodent
animals has been designed and employed in this system. The
animal’s breathing and heartbeat could cause motion artefacts
that influence the image quality, especially when the scanningspeed is low. Hence both systems are capable to perform
real-time imaging, enabling a precise and time-saving position
adjustment of the animal during the experiment. The CSLO scansystem can reach 15 Hz in C-Scan Mode, while the OCT shows
B-Scans with 40 Hz. Our results demonstrated the dual-modality
ophthalmoscope system successfully acquired high-quality
images of the retina of a SD rat. The integrated CSLO and SDOCT gives clear anatomical information with high lateral and axial
resolution in real-time. Due to its modular setup it can be used foranimals with different sizes and can be upgraded with additional
functionalities. In all, it can be used widely for various researches,#PhotonicsAsia

167

Conference 10024:
Optics in Health Care and Biomedical Optics VII
Samara Univ. (Russian Federation); Alexander A.
Moryatov, Sergey V. Kozlov, Samara State Medical Univ.
(Russian Federation); Valery P. Zakharov, Samara Univ.
(Russian Federation)

including, physiology and pathology of fundus diseases, preclinical studies, and visual neuron studies.

10024-183, Session Post

Image segmentation of flow sample in
Fourier domain Doppler optical coherence
tomography
Yong Huang, Shaoyan Xia, Xiaodi Tan, Beijing Institute ofTechnology (China)
In Fourier domain Doppler optical coherence tomography (FDOCT), intensity image and phase image can determine sample
structure and flow condition, separately. To provide threedimensional flow field simulation of sample, we employ the active
contours method combining intensity and phase information for
OCT B-scan images segmentation. In this segmentation process,initial contour of tissue is obtained from the intensity image
by active contours method, then the corresponding region ofphase image is processed. For phase image segmentation, thegray value of linking flow area is used as threshold for achieving
accurate flow region. Thus, the different areas are determined intissue structure.

Pilot study results of autofluorescence imaging for ex vivo humanskin samples with pathological tissues are presented using
hyperspectral registration camera.
457 nm laser and a powerful blue LED at 450 nm with abroadband color filter ss-4 (transmission coefficient in the rangeof 500-690 nm is 0%) are selected as the excitation source ofautofluorescence. The system of hyperspectral imaging candisplay the images with spectral resolution of up to 2.1 nm in
the range of 450-750 nm and provides the capability to obtain
images at a rate of 3 frames per second with a resolution of
1360x1024 pxl (maximum increase in scanning area is 7x7cm). Autofluorescence imaging results are compared with thehistological analysis of samples provided of Samara State Medical
University. The obtained data has been processed in MATLAB
R2014a.
Analysis of the autofluorescent data of skin samples based on
the spectral ranges of 520-580 nm and 620-690 nm due tothe presence of flavins and porphyrins in tissues is performed.
Autofluorescent images obtained by excitation of laser (457 nm)
and LEDs (450 nm) with a broadband color filter are compared.
As a result, the maps of basic fluorophores of skin with neoplasm
are presented, and shown that pigmented melanoma, unlike anormal skin, is characterized by a significant decline of intensity
in the range of 520-580 nm relatively to range of 620-690 nm.

10024-184, Session Post

Microencapsulation of indocyanine green
in perfluorohexane-shelled microbubbles
for application of cancer treatment

10024-39, Session 7

Shuya Han, Zhiqiang Zhu, Univ. of Science and Technology
of China (China); Rong Ma, Second Affiliated Hospital of
Chongqing Medical Univ. (China); Fengjing Zhong, Ting Si,
Univ. of Science and Technology of China (China); Ronald
X. Xu, The Ohio State Univ. (United States)
Indocyanine green(ICG), a fluorescent dye with a near-infrared
spectrum of absorption and fluorescence, has shown promisingprospect in cancer treatment because of its minor toxicity, itsselectively over-heating effect, its release of reactive oxygen
species upon laser irradiation and the penetration of NIR
light. However, ICG is unstable in vivo environment and canbe quickly removed from circulation by the liver to bile juice.
Microencapsulation is a good way to improve the stability of
ICG and to prolong its useful life after injection, which also helps
improve its contrast effect. Perfluorocarbon-based emulsions(i.e.
PFH microbubbles) are promising vehicles for triggered deliveryof payloads thanks to their ability to undergo a phase change
from liquid to gas upon ultrasound activation. Nonetheless,loading hydrophilic agents(i.e. ICG) into PFH emulsions is difficult
due to their insolubility in PFH. Therefore, we use this coaxial
flow-focusing technique to encapsulate ICG solution into PFHshelled microbubbles to overcome these limitations. The effects
of main parameters on the process are studied systematicallyfor enhanced microbubble morphology. In cell culture studies,microbubble treatment with ultrasound activation remarkably
increases cancer apoptosis and inhibits cell proliferation.
Fluorescence imaging is studied after intraperitoneal injection
in mice. Our results suggest that this therapy may be a useful
method for cancer treatment.

10024-185, Session Post

Visualization of pathological tissues using
autofluorescence imaging

Plasmon-enhanced UV lasing in ZnO
whispering-gallery microcavities (Invited
Paper)
Chunxiang Xu, Qiuxiang Zhu, Junfeng Lu, Yueyue Wang,
Zengliang Shi, Southeast Univ. (China)
In recent years, whispering-gallery mode (WGM) lasing fromhexagonal ZnO microrods has drawn much attention due to
its low loss, low threshold and high Q factor. Ones have madegreat efforts to improve lasing performance. Surface plasmons(SPs) as a collective electronic oscillation have been successfully
introduced on a metal-dielectric interface to improve opticalproperties, such as enhanced surface Raman scattering andenhanced fluorescence. The metal decorated WGM microcavity
constructs a more advantageous coupling configuration between
the ZnO interband emission and the surface plasmon (SP)because both of the evanescent waves are mainly confined on
the microcavity surface, where the former reflects totally andinternally at the ZnO/air boundary while the latter is localized
in the metal/ZnO interface. This effective coupling is expected
to contribute to improve the lasing performance, but few
investigations have been reported so far. Here the plasmon
enhanced spontaneous emission and whispering-gallery
mode (WGM) lasing from hexagonal ZnO microrod has been
investigated through decorating metal nanoparticles (such as Al,
Ag and Au) on the cavity surface. About 200-folds and tensfolds enhancement of spontaneous and stimulated emission havebeen observed in our experiments. The lasing threshold and Q
factor have also been improved. The related energy coupling andcharge transfer processes have been investigated systematically.
These results are helpful for designing high efficient optical andphoto-electronic devices.
This work was supported by ‘‘973’’ Program (2013CB932903),
and NSFCs (61275054, 61475035).

Larisa A. Zherdeva, Ivan A. Bratchenko, Oleg O. Myakinin,
168

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-40, Session 7

Utrasound-assisted gold nanoparticle
beacon for the detection of sensibilityof tumor cells to chemotherapy (Invited
Paper)
Qiumei Zhou, Yi Ma, Yueqing Gu, China Pharmaceutical
Univ. (China)
The failure of chemotherapy, a serious problem in anticancer
therapy, is substantially caused by either intrinsic or acquired
gene mutations or overexpression of specific proteins. However,there is currently a lack of selective and effective platforms forthe detection of sensibility of living tumor cells to chemotherapy.
Here, we demonstrate a gold nanopartical beacon (hDAuNP
Beacon) is capable of detecting the mRNA expression of
drug resistance related gene, as well as the responds of tumor
cells to anticancer chemotherapy. In this study, based on therelationship between mRNA expression of resistance gene andtumor drug-resistance, the hDAuNP Beacon was designed,
synthesized and respectively used to detect multidrug resistance
1 (MDR1) mRNA and breast cancer susceptibility gene-1 (BRCA1)mRNA expression in living cells. With the help of ultrasonicwave, which could improve the permeability of cell membranes,
the cellular uptake and the detection sensitivity of hDAuNP
beacon are improved notably. The difference in MDR1 andBRCA1 mRNA expression in living cancer cells can be detected
exactly by hDAuNP beacon assisted with ultrasound. According
to the fluorescent signals in living cells, the sensibility canbe recognized for tumor cells to Doxorubicin, Cisplatin and
Paclitaxel. Furthermore, the expression of p-glycoprotein (P-gp)
was regulated by the antisense DNA sequences of MDR1 hDAuNP
beacon, and the Doxorubicin resistance was reversed by MDR1
hDAuNP beacon. Therefore, hDAuNP beacon may be a new
strategy for the personalized medicine and the precision medical.

10024-41, Session 7

Optofluidic microresonators in biosensing
and imaging (Invited Paper)
Xiang Wu, Fudan Univ. (China); Shusen Xie, Fujian Normal
Univ. (China)
Hollow-core optofluidic microresonators (OFMRs) currently
attract many researchers’ attentions due to their potential
applications in scientific and industrial fields. OFMRs havethe unique capabilities of both the easy integration withmicrofluidics and the excellent optical confinement of optical
microrensonators. The outstanding advantage makes OFMRs as
one of promising optofluidic platform for ultra-sensitive biosensing and high-resolution imaging. In this talk, we first describe
the principle of OFMRs and review the current applications on invitro bio-sensing and imaging. We will present the OFMRs basedon ring resonators and Fabry–Pérot cavities and the applications
on biosensing and imaging. The outlooks of the development andpotential applications on in-vivo bio-sensing and imaging are also
provided.

10024-43, Session 7

Near-infrared fluorescent polymer dotswith durable brightness and long-term
stability for in vivo tumor tracking
Liqin Xiong, Fengwen Cao, Yixiao Guo, Shanghai Jiao
Tong Univ. (China)
In recent years, conjugated polymer dots have gained interest as
a new class of fluorescent probes due to their attractive chemicaland optical features. However, to date, only a few studies onwhole-body imaging of polymer dots in living mice have beenreported, mainly due to the challenges of designing polymer
dots that show strong and narrow-band emissions in the nearinfrared (NIR) region, and their unfavorable in vivo performanceafter systemic injection. To address this problem, we prepared
the NIR-emitting polymer dots by encapsulating the dye NIR775
into the matrix of MEH-PPV dots using a nanoprecipitation
method. The prepared NIR polymer dots exhibited narrowband NIR emission at 778 nm with a full width at half maximum(FWHM) of 20 nm, and displayed a large Stokes shift (>300nm) between the excitation and emission maxima. Moreover,these NIR polymer dots showed long-term colloidal stability
and photostability in water at 4 oC for at least nine months,
and were able to imaging vasculature of xenografted U87MG
tumors in living mice after intravenous injection. We further
use the NIR775 dye-doped MEH-PPV polymer dot system as afluorescent nanoprobe for in vitro HeLa cell labeling and in vivo
long-term HeLa tumor tracking. These synthesized NIR polymer
dots exhibited unique capabilities for in vivo cell tracking, such as
long-term luminescence and photostability, and high sensitivity.
These studies provide a foundation for the development of thewhole-body tumor cell tracking based on the NIR polymer dots
as fluorescent nanoprobes.

10024-44, Session 710024-42, Session 7

Multiple gold-dimer detection from large
scattering background
Xin Hong, Zheng Jin, Dalian Univ. of Technology (China)
Gold nanoparticles exhibit unique plasmonic optical properties
in visible to near infrared band. Especially when two particles
are closely linked, the coupling effect existing at the gap can

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produce a strongly enhanced local field. These properties makegold particles more attractive to be employed as molecular
probes in biomedical related fundamental and clinical researches.
However, in the bio-system exist many large molecules or groups,
whose optical signals can strongly depress the gold particles
into undetectable. With the aim to detect the targets from thecircumstance of scattering disturbance, we employed gold dimer
as molecular probes by taking advantage of their plamonic
coupling effect. The coupling effect of a gold-dimer is associatedwith the angle between the excitation polarization and the dimer
axis ,while the optical signals strength of other large molecules
or groups aren’t sensitive to the polarization direction of theexcitation light. A good match of excitation condition with thedimer axis is crucial to extract the probe from the backgroundnoise. To make the detection without target lose, it requires
each randomly placed dimer axis to be matched with theexcitation. The simulation results show that 45degrees between
the excitation polarization and the dimer axis can produce an
optimum signal. We can detect multiple gold-dimer by observing
the change of optical signals strength in the same place with therotation of the polarization. Thus here, in this paper we proposeda method to extract multiple dimer probes from the large
background noise without target lose.

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Anti-hepatocarcinoma effects ofberberine-nanostructured lipid carriers
against human HepG2, Huh7, and EC9706
cancer cell lines (Invited Paper)
Xiang-ping Meng, Henan Univ. of Science and Technology(China); Hua Fan, Guangdong hinabiotech Co., Ltd.

#PhotonicsAsia

169

Conference 10024:
Optics in Health Care and Biomedical Optics VII(China); Yifei Wang, Jinan Univ. (China); Zhi-ping Wang,
Guangdong Pharmaceutical Univ. (China); Tongsheng
Chen, South China Normal Univ. (China)
Hepatocarcinoma and esophageal squamous cell carcinomas
threaten human life badly. It is a current issue to seek theeffective natural remedy from plant to treat cancer due to theresistance of the advanced hepatocarcinoma and esophageal
carcinoma to chemotherapy. Berberine (Ber), an isoquinoline
derivative alkaloid, has a wide range of pharmacologicalproperties and is considered to have anti-hepatocarcinoma
and antiesophageal carcinoma effects. However its low oral
bioavailability restricts its wide application. In this report, Ber
loaded nanostructured lipid carriers (Ber-NLC) was prepared by
hot melting and then high pressure homogenization technique.
The in vitro anti-hepatocarcinoma and antiesophageal carcinoma
effects of Ber-NLC relative to efficacy of bulk Ber were evaluated.
The particle size and zeta potential of Ber-NLC were 189.3 ± 3.7
nm and ?19.3 ± 1.4 mV, respectively. MTT assay showed that BerNLC effectively inhibited the proliferation of human HepG2 andHuh7 and EC9706 cells, and the corresponding IC50 value was 9.1µg/ml, 4.4 µg/ml, and 6.3 µg/ml (18.3µg/ml, 6.5µg/ml, and 12.4µg/
ml µg/ml of bulk Ber solution), respectively. These results suggestthat the delivery of Ber-NLC is a promising approach for treatingtumors.

10024-45, Session 7

Optical manipulation of nanoparticles
based on whispering gallery mode opticalresonators
Haotian Wang, Xiang Wu, Deyuan Shen, Fudan Univ.
(China)The whispering Gallery mode (WGM) optical resonator enables
a great optical intensity enhancement in a very small volume,
which gives a promising platform for trapping and manipulating
the micro- or nano-particles. The light could be coupled into
the resonator to excite the WGMs using the waveguide placed
close to the resonator or illuminating the resonators directlyin the free-space. In the latter case, more interesting is that a
special optical field distribution called photonics nanojet (PNJ)
is formed even if the resonator is off-resonance. The PNJ also
confines the optical field within a very small region on the
shadow side of the resonator. In this paper, we demonstrate thelocalized optical manipulation of nanoparticles in the resonatorbasing on generating the standing-wave WGM and PNJ. The
locations of the trapped particles are controlled by tuning theincident field. The trapping stability of the nanoparticles underthe Brownian motion is also analyzed. The manipulation systempresented in this paper possess enormous potential in precisely
manipulation of nanoparticles, such as directed nanoassemblyand manipulating single molecules.

proportionally to the photon density of state (DOS) at related
frequency. Therefore, structures that can increase DOS aredesired in SERS applications. Photonic crystal (PC), which has
periodic nanostructures relevant to the length of light, hasphotonic band gaps that forbidden the propagation of light insome frequency range. Therefore, PC has increased DOS at theband edge with respect to homogenous medium and provides
a good candidate medium for the boost of light and plasmonic
materials interactions. In this paper, we integrated plamsonicmaterials with PC to boost SERS signals and discussed thefabrication methods of integration, as well as the factors that
affect SERS signals in the transducing process of biosensors
with respect to high sensitivity, multiplicity and simplicity. Our
results showed that the micro/nano structure of photonic crystal
could be used as a good platform for SERS sensors in biomedical
applications like point of care testing (POCT), bacteria detection,
cell analysis or multiplex bioassays.

10024-47, Session 7

Detection limit improvement for a mobile
lateral flow assay reader
Boonsong Sutapun, Lalita Saisin, Suranaree Univ. ofTechnology (Thailand); Ratthasart Amarit, Armote
Somboonkaew, National Electronics and Computer
Technology Ctr. (Thailand); Oraprapai Gajanandana,
Orawan Himananto, National Ctr. for Genetic Engineeringand Biotechnology (Thailand)
Lateral flow immunoassays are widely used for qualitative
measurement in non-specialize laboratory and in low-resource
settings. Recent developments in the mobile-phone strip
readers have further improved the device’s sensitivity as well asother advantages including quantitative results, reading error
reduction, compact size and simple data handling. We showedthat manually adjusting the camera settings, instead if using
the automatic setting mode, to achieve a full scale bit-depth
can significantly improve the detection limit of the strip reader.
The strip reader was developed based on a CMOS camera and agreen LED light source. Camera parameters including exposure
time, gain, and contrast were manually adjusted until the fullscale of the camera bit depth was achieved. The performanceof the strip reader was evaluated for the detection of the
Acidovorax avenea subsp. Citrulli (Aac), the bacterial fruit blotchof watermelon. We found that the detection limit of the reader
when the optimal camera settings were used was 5x105 CFU/
mL which was 10 times better than the detection limit of thereader utilized the camera automatic mode. This technique canbe readily applied to any existing camera-based strip readers tosignificantly improve the reader’s performance without hardware
modifications.

10024-48, Session 710024-46, Session 7

SERS signals in the transducing process ofbiosensors
Xiangwei Zhao, Zhongde Mu, Bing Liu, Delong Wang,
Zhongze Gu, Southeast Univ. (China)
Raman-scattered photons from a molecule can directly reveal thesignature of vibrational energy states of the molecule and theirintensities can be greatly enhanced by plasmonic nanostructuresor surfaces of plasmonic materials, which leads to high sensitivity.
Therefore, surface enhanced Raman spectroscopy (SERS)
attracts more and more attentions in bioanalysis recently.
The probability of spontaneous Raman scattering is directly

170

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Evaluation of free-radical scavenging
and anti-oxidative capacity of polydatinnanostructured lipid carriers
Xiang-Peng Meng, Henan Univ. of Science and Technology(China); Fan Shi, Guangdong Pharmaceutical Univ
(China); Yifei Wang, Jinan Univ. (China); Zhi-ping Wang,
Guangdong Pharmaceutical Univ. (China); Tongsheng
Chen, South China Normal Univ. (China)
Cellular damage induced by free-radicals like reactive oxygen
species has been implicated in several diseases. 2, 2-azobis(2amidino-propane) dihydrochloride(AAPH) generates two potent
ROS capable of inducing lipid peroxidation: alkoxy radical(RO-)

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
and peroxy radical(ROO-). These radicals are similar to those thatare physiologically active and thus might initiate a cascade of
intracellular toxic events leading to oxidation, lipid peroxidation,
DNA damage and subsequent cell death. Hence naturally
anti-oxidant play a vital role in combating these conditions. In
this study, polydatin loaded nanostructured lipid carriers (PolNLC) was prepared by hot melting and then high pressure
homogenization technique. The effects of Pol-NLC on free
radical scavenging and antioxidative capacity is investigated.
The particle size and zeta potential of Pol-NLC were 113.9 ± 1.1 nm
and ?16.3 1 ± 0.27 mV, respectively. By free radical scavenging
assays, the IC50 value of Pol-NLC were 28.71, 9.83 ?g/mL with
DPPH, ABTS assay respectively, and 0.143 mg ferrous sulfate/1
mg Pol-NLC with FRAP assay. These results indicated that the
antioxidant properties of Pol-NLC hold great potential used as analternative to more toxic synthetic antioxidants as an additive in
food, cosmetic and pharmaceutical preparations for the oxidative
diseases treatment.

10024-49, Session 8

Quantification of reactive oxygen species
for photodynamic therapy (Invited Paper)
Buhong Li, Fujian Normal Univ. (China)
Photodynamic therapy (PDT) is an effective therapeutic modalitythat uses a light source to activate light-sensitive photosensitizers
to treat both oncologic and nononcological indications.
Photosensitizers are excited to the long-lived triplet state, andthey react with biomolecules via type I or II mechanism resulted
in cell death and tumor necrosis. Free radicals and radical ionsare formed by electron transfer reactions (type I), which rapidly
react with oxygen leading to the production of reactive oxygen
species (ROS), including superoxide ions, hydroxyl radicals
and hydrogen peroxide. Singlet molecular oxygen is produced
in a Type II reaction, in which the excited singlet state of thephotosensitizer generated upon photon absorption by theground-state photosensitizer molecule undergoes intersystemcrossing to a long-lived triplet state. In this talk, the fundmental
mechanisms and detection techniques for ROS generation in
PDT will be introduced. In particular, the quantification of singlet
oxygen generation for pre-clinical application will be highlighted,
which plays an essential role in the establishment of robust
singlet oxygen-mediated PDT dosimetry.

10024-50, Session 8

Pdot probes for stem cell labeling andphototherapy (Invited Paper)
Changfeng Wu, Jilin Univ. (China)
Semiconductor polymer dots (Pdots) have been demonstrated
for a wide variety of biological applications. On one hand, thesuperior properties of Pdots have established their enormous
potential in biology and medicine as highly bright probes forcellular imaging and in vivo imaging. However, little is known
whether stem cells can be effectively labeled by Pdots forlong term cell tracking in vitro and in vivo. On the other hand,
semiconductor polymers have been frequently exploited for
amplifying the singlet oxygen generation by taking advantagesof their large absorption coefficient and efficient energy
transfer to the photosensitizers. The energy transfer mechanism
provides new opportunities for designing Pdot platforms forphototherapy. In one approach, photosensitizer molecules
can be physically encapsulated in Pdots by hydrophobic
interactions. The densely packed Pdots comprised conjugatedpolymer and photosensitizer in close proximity that facilitate theamplification of singlet oxygen generation by energy transfer. In
alternative approaches, covalent incorporation of photosensitizer
in conjugated polymers could amplify the singlet oxygen

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generation by energy transfer from the conjugated backbone tophotosensitizers.
In this presentation, we will present several new types of Pdot
probes for stem cell labeling and phototherapy. The hydrophobic
semiconductor polymers tend to form small, stable and denselypacked Pdot probes. The large absorption cross section, highfluorescence quantum yields, and good biocompatibility arepromising for stem cell tracking in vitro and in vivo. The Pdots
coated with a cell penetrating peptide showed remarkableendocytic uptake efficiency as compared to carboxyl Pdots.
The Pdot-labeled stem cells can be traced for 15 generations
in vitro and tracked over weeks in vivo after tail-vein injection.
For PDT applications, incorporation of photosensitizer inside
the Pdots can amplify singlet-oxygen generation by efficientenergy transfer. We developed Pdot photosensitizers and thensystematically characterized the spectroscopic properties,
which showed efficient singlet oxygen generation amplified
by inter-particle energy transfer. The effectiveness of Pdots as
PDT photosensitizer was demonstrated by in vitro assay, whichindicate that the Pdots are able to damage cancer cells under
low Pdot concentration and light dose. Moreover, the PDT effectof the Pdots was further investigated in vivo with tumor-bearing
mice model, and the xenograft tumors were significantly inhibitedor eradicated in certain cases.

10024-51, Session 8

Quantitative photobiomodulation (Invited
Paper)
Timon Cheng-Yi Liu M.D., Ling Zhu, South China Normal
Univ. (China); Quan-Guang Zhang, South China Normal
Univ. (China) and Augusta Univ. (United States)
Photobiomodulation (PBM) has been usually studied withstatistical approaches, but its reproducibility has been very low.
It was reanalyzed with the quantitative difference (QD) in thisstudy. The golden logarithm (GL) was defined as the logarithm tothe base the golden ratio, about 0.618. The QD of two parameters
was defined as the absolute value of the GL of their ratio. The
QD was significant or very significant if it is equal to or larger
than a or b. The a/b of the cellular/molecular/psychological QD,
the organ/tissue QD and the body QD were 0.80/1.27, 0.47/0.80
and 0.27/0.47, respectively. For NeuroThera Effectiveness andSafety Trial of Infrared Laser Therapy for Ischemic Stroke (NEST),the therapeutic effects were of very significance for NEST-1,
of significance for NEST-2, but of no significance for NEST-3
according to organ/tissue QD, which suggested that ischemic
stroke should be classified into two categories: PBM-sensitive
and PBM-resistant. For the well-known randomized clinical trialof acupuncture for chronic knee pain, QD analyses showedneedle, laser, or sham acupuncture significantly changed mostof parameters compared with control at 12 weeks or 1 year. The
mechanism of signal transduction pathway still held because
there were function-specific signal transduction pathways(FSPs) according to molecular QD, and PBM might promote theactivation of one or more FSPs if the observation term is longenough. It was concluded that the quantitative PBM may not onlyof high reproducibility, but also promote the translation of PBM
studies into low level laser/light therapy.

10024-52, Session 8

The florescence detection in the treatmentof CIN with photodynamic therapy
Lifeng Wang, Defu Chen, Naiyan Huang, Ying Gu, Chinese
PLA General Hospital (China)
The cervical intraepithelial neoplasias (CIN) is the abnormal
growth of squamous cells on the surface of the cervix, and is#PhotonicsAsia

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
the potentially premalignant transformation. The photodynamic
therapy (PDT) is a form of phototherapy in which light interacts
with a photosensitizer and singlet oxygen is generated to tokill cells. Compared the traditional cone resection treatment to
the CIN, the PDT method introduces less damage to the cervix
uteri and the function can be reserved. We have performed PDT
treatment to the patients who are intravenously ejected with
Hematoporphyrin, the mount of which is proportional to the massof the patients and irradiated by the 630 nm continues laser. The
florescence spectrum of the Hematoporphyrin can help doctors
to find out the accumulation of the photosensitizer in the lesion
area. Based on a Y-type fiber, we have established a florescence
detection system to record the florescence spectrum of theHematoporphyrin. A 405 nm continuous laser is transmitted ina fiber to simulate the Hematoporphyrin, and the fluorescencewith central wavelength at 630 nm and 690 nm is transmitted
by another fiber and detected by a spectroscope. A band filter isused to eliminate the 405 nm laser and gather the florescence at
maximum amount. The intensity of the fluorescence significantly
decreased after the radiation, which means the photosensitizer isconsumed by the 630 nm laser but a few amount is still left in thelesion area.

10024-53, Session 8

In vitro photodynamic inactivation effectsof cationic benzylidene cyclopentanone
photosensitizers on clinical fluconazoleresistant candida albicans planktonic cells
and biofilms
Shaona Zhou, Ying Wang, Zulin Ye, Ying Gu, Chinese PLA
General Hospital (China)
Background: An increasing prevalence of Candida infections
has emerged with the wide use of immune-suppressants andantibiotics. Photodynamic inactivation (PDI) as a new approach
to treat localized Candida infections is an emerging andpromising field nowadays. This study evaluated the efficacyof photodynamic therapy using two new Cationic benzylidene
cyclopentanone photosensitizers(P1 and P2) against strains ofclinical fluconazole–resistant Candida albicans.
Methods: Suspensions and biofilms of Candida species wereincubated with P1 and P2 concentrations (0.25~50 ?M) for 30 min
followed by 532-nm laser irradiation. For planktonic suspensions,viability of cells was assayed by CFU counting. For biofilms, themetabolic activity was evaluated by XTT.
Results: In PDI of a planktonic culture of clinical fluconazole–
resistant Candida albicans, P2 showed the higher efficacy. Afterincubation with 25 µM of P2 for 30 min and irradiation with 532nm laser (36 J/cm2), the viability of C. albicans planktonic cells
decreased by 3.84 log10. For biofilm cells, a higher light dose of
75 mW/cm2 was necessary to achieve 97.71% metabolic activity
reduction.
Conclusions: The results of this investigation demonstrated thatbenzylidene cyclopentanone photosensitizer?P2?is an efficientphotosensitizer to kill C. albicans. Moreover, single-species
biofilms were less susceptible to PDT than their planktonic
counterparts.

Hospital (United States); Ying Gu, Chinese PLA General
Hospital (China)
Background: With the increasing emergence of multidrugresistant (MDR) bacterial strains, there is a pressing need for thedevelopment of alternative treatment for infections. Antimicrobial
blue light (aBL) has provided a simple and effective approach.
Methods: We first investigated the effectiveness of aBL (415 nm)
inactivation of USA300 (a Methicillin-resistant Staphylococcus
aureus strain) both in the planktonic and biofilm forms. The
survival of the bacteria in suspensions was determined byserial dilution and that of the biofilm-embedded bacteria wasdetermined by bioluminescence quantification. Using a mousemodel of thermal burn infected with USA300, we further
assessed the effectiveness of aBL for treating localized infections.
Bioluminescence imaging was performed to monitor in real time
bacterial viability in vivo.
Results: In vitro study showed that, for the planktonic counterpartof the bacteria or the 24-h-old biofilms, an irradiance of 55 mW/
cm2 for 60 min resulted in a 4.61 log10 or 2.56 log10 inactivation,
respectively. In vivo study using infected mouse burns
demonstrated that a 2.56-log10 inactivation was achieved after
100-mW/cm2 irradiation for 62 min.
Conclusions: aBL is a potential alternative approach for treating
Methicillin-resistant Staphylococcus aureus infections.

10024-10, Session 9

Implantable multifunctional
optoelectronic neural probe
Xing Sheng, Tsinghua Univ. (China)
Understanding neural structures and functions is important toresolve the mystery of the complex brain. Recent progresses inthe development of genetically encoded actuators and indicators
have given birth to versatile and powerful tools for monitoringand manipulating neuronal activities both temporally andspatially, using optical methods. Here we present an integrated
optoelectronic probe system based on high performance,
microscale photonic devices including LEDs and photodetectors,
which can be implanted deeply into the brain and provides
new insights on interactions between light and neural systems.
A gallium indium nitride (GaInN) blue LED, a gallium indium
aluminum phosphide (GaInAlP) yellow LED, as well as a gallium
arsenide (GaAs) photodetector are combined and interconnected
on a flexible thin-film polymer substrate, forming an injectableneedle. New techniques including epitaxial liftoff and transfer
printing are developed to fabricate and assemble these thinfilm microscale inorganic semiconductor devices onto theorganic substrate. The blue LED serves as a light source toexcite the genetically encoded calcium indicator GCaMP6. The
photodetector with a specifically designed band selective opticalcoating is used to probe the GCaMP6 fluorescent signal withhigh sensitivity. The yellow LED allows us to activate the chloride
pump halorhodopsin, which inhibits local neural activities.
Compared to other light sources like optical fibers, external lightsources and detectors, these deeply injected photonic devices
will provide collimated, localized and precise light generation anddetection. By using such an integrated optoelectronic system, we
hope to realize close loop monitoring and manipulation of neuralactivity in vivo.

10024-54, Session 8

Antimicrobial blue-light inactivationof methicillin-resistant staphylococcus
aureus: in vitro and in vivo study
Yucheng Wang, Chinese PLA General Hospital (China) andNankai Univ. (China); Tianhong Dai, Massachusetts General

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Conference 10024:
Optics in Health Care and Biomedical Optics VII

10024-55, Session 9

Wavelet phase coherence analysis
of cerebral tissue oxyhemoglobin
concentrations and arterial blood pressure
signals in subjects with sleep deprivation
Lingguo Bu, Jianfeng Li, Fangyi Li, Heshan Liu, Shandong
Univ. (China); Zengyong Li, Shandong Univ. (China) andNational Research Ctr. for Rehabilitation Technical Aids
(China)There are occupational risks in sailors due to long term work inthe sea, especially cardiovascular and cerebrovascular diseases.
Sleep deprivation is one of the risk factors in sailors. This study
aims to assess the relationship between spontaneous oscillations
in changes in cerebral tissue oxyhemoglobin concentrations(Delta [HbO2]) and arterial blood pressure (ABP) signals insubjects with sleep deprivation using wavelet phase coherence
analysis (WPCO).
Total 20 healthy subjects (including 10 male and 10 female, age:25.5 ± 3.5 years) were recruitedfrom Shandong University anddivided into two groups: one was without deprivation group(Group A) and the other was with 24 hour sleep deprivationgroup (Group B). Continuous recordings of near-infrared
spectroscopy (NIRS) and ABP signals were obtained fromsimultaneous measurements in each subject during the rest andtask, respectively. The coherence between Delta [HbO2] and ABPoscillations in six frequency intervals (I, 0.6–2 Hz; II, 0.145–0.6 Hz;
III, 0.052–0.145 Hz; IV, 0.021–0.052 Hz; V, 0.0095–0.021 Hz; andVI, 0.005–0.0095 Hz) was analyzed using wavelet coherence
analysis.
At rest, the WPCO in intervals III was significantly lower in GroupB than in Group A (F = 4.367, p = 0.044 for III). In task, Group B’s
WPCO in intervals IV was significantly higher than Group A (F =8.045, p = 0.007 for interval IV). The results suggest that waveletbased coherence analysis of NIRS signal can provide a method toassess the risks of cardiovascular and cerebrovascular diseases insailors with sleep deprivation.

10024-56, Session 9

Quantitatively differentiating
microstructural variations of skeletal
muscle tissues by multispectral Mueller
matrix imaging
Yang Dong, Honghui He, Chao He, Tsinghua Univ. (China);
Hui Ma, Graduate School at Shenzhen, Tsinghua Univ.
(China)Polarized light is sensitive to the microstructures of biologicaltissues and can be used to detect physiological changes.
Meanwhile, spectral features of the scattered light can also
provide abundant microstructural information of tissues. In thispaper, we take the backscattering 3?3 linear polarized Mueller
matrix images of bovine skeletal muscle tissues during the 24hour experimental time, and analyze their multispectral behavior
using quantitative Mueller matrix parameters. In the processesof rigor mortis and proteolysis of muscle samples, multispectral
frequency distribution histograms (FDHs) of the Mueller matrix
elements can reveal rich qualitative structural information,and their corresponding four central moment parameters
can be used as quantitative indicators for the characteristic
microstructural features of tissues. In addition, we analyze thetemporal variations of the sample using the multispectral Mueller
matrix transformation (MMT) parameters. The experimental
results indicate that the different stages of rigor mortis andproteolysis for bovine skeletal muscle samples can be judged by

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Follow us on:these MMT parameters. Contrast mechanism of the multispectral
Mueller matrix imaging for skeletal muscle tissues is revealed
by Monte Carlo (MC) simulations based on the sphere-cylinder
birefringence model. The relationship between the multispectralfeatures of the MMT parameters and the microstructures ofthe samples is studied. The results presented in this work showthat combining with the multispectral technique, the FDHs,
central moments and MMT parameters can characterize themicrostructural variation features of skeletal muscle tissues. The
techniques have the potential to be used as tools for quantitative
assessment of meat qualities in food industry.

10024-57, Session 9

Accurate assessment of liver steatosis in
animal models using a high-throughput
Raman fiber-optic probe
Kevin C. Hewitt, Ian P. Alwayn, Dalhousie Univ. (Canada);
Haishan Zeng, Hanna C. McGregor, Michael A. Short, BC
Cancer Research Ctr. (Canada); Samia B. Fashir, Heidi
Sapp, Javad G. Rad, Dalhousie Univ. (Canada)Due to the shortage of healthy donor organs, steatotic livers
are commonly used for transplantation, placing patients at
higher risk for graft dysfunction and lower survival rates. Raman
Spectroscopy is a technique which has shown the ability to
rapidly detect the vibration state of C–H bonds in triglycerides.
The aim of this study is to determine whether conventional
Raman spectroscopy can reliably detect and quantify fat in an
animal model of liver steatosis. Mice and rats fed a methionine
and choline-deficient (MCD) and control diets were sacrificed onone, two, three and four weeks’ time points. A confocal Raman
microscope, a commercial Raman (iRaman) fiber optic probe
and a highly sensitive Raman fiber optic probe system, the latter
utilizing a 785 nm excitation laser, were used to detect changes
in the Raman spectra of steatotic mouse livers. Thin layer
chromatography was used to assess the triglyceride content ofliver specimens, and sections were scored blindly for fat content
using histological examination. Principal component analysis(PCA) of Raman spectra was used to extract the principal
components responsible for spectroscopic differences with
MCD week (time on MCD diet). Confocal Raman microscopy
revealed the presence of saturated fats in mice liver sections.
A commercially available handheld Raman spectroscopy probe
could not distinguish the presence of fat in the liver whereas
our specially designed, high throughput Raman system could
clearly distinguish lobe-specific changes in fat content. In the left
lobe in particular, the Raman PC scores exhibited a significant
correlation (R2 = 0.96) with the gold standard, blinded scoring byhistological examination. The specially designed, high throughput
Raman system can be used for clinical purposes. Its application
to the field of transplantation would enable surgeons todetermine the hepatic fat content of the donor’s liver in the fieldprior to proceeding with organ retrieval.
Next steps include validating these results in a prospective
analysis of human liver transplantation implant biopsies.

10024-58, Session 9

Polarized light imaging for nondestructive quantitative assessment ofvulvar lichen sclerosis
YingJie Qu, Ximing Zhou, Yu Q. Meng, Li Yuan, Yao Qiu,
Peng Liu, Wenqi Ren, Ming Z. Sun, Univ. of Science andTechnology of China (China); Shufang Chang, Chongqing
Medical Univ. (China); Ronald X. Xu, The Ohio State Univ.
(United States)#PhotonicsAsia

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Conference 10024:
Optics in Health Care and Biomedical Optics VII
Vulvar lichen sclerosis (VLS) is a chronic skin disorder ofextragenital skin with an increasing risk of developing vulvar
cancer, which often goes undetected for years. Hyperkeratosis
and areas of sclerosis often occur, which leads to the structuralchanges of the affected area. One of the underlying causes is
associated with the decrease and homogenization of collagenfibers causing the changes of fiber orientation. However, few
method is available for quantitative detection of VLS. Clinician’s
examination is subjective and may lead to misdiagnosis. Polarized
light imaging is a potentially effective method for noninvasive
detection of VLS. In this paper, we studied the optical propertiesof vulvar tissue and developed a polarized light imaging systemfor quantitative assessment. First, a five-layered optical model
was proposed for simulating Mueller matrix of vulvar tissue. Thena polarized light imaging system was developed for noninvasive
detection of the order of alignment of the fibrous structure intissues,?or structural anisotropy ,and the orientation of the fibers
via the analysis of Mueller matrix. Thus, structural anisotropy andfiber orientation quantification can be achieved for the superficial
layer with optical sectioning. We demonstrated on the VLS
optical sectioning that this polarized light imaging method had atechnical potential for non-destructive quantitative assessmentof VLS.

10024-59, Session 9

Hyperspectral-stimulated Raman
scattering imaging of cholesteryl ester
accumulation: new avenue to diagnosis ofhuman prostate cancer
Jun Du, Beihang Univ. (China); Ping Wang, Huazhong Univ.
of Science and Technology (China); Shuhua Yue, BeiHang
Univ. (China)
Most prostate cancers (PCa) are slowly growing, and only theaggressive ones require early diagnosis and effective treatment.
The current standard for PCa diagnosis remains histopathology.
Nonetheless, for the differentiation between Gleason score 6(low-risk PCa), which can be left without treatment, and Gleason
score 7 (high-risk PCa), which requires active treatment, theinter-observer discordance can be up to 40%. Our previous
study reveals that cholesteryl ester (CE) accumulation induced
by PI3K/AKT activation underlies human PCa aggressiveness.
However, Raman spectromicroscopy used in this study could
only provide compositional information of certain lipid droplets(LDs) selected by the observer, which overlooked cell-to-cellvariation and hindered translation to accurate automateddiagnosis. Here, we demonstrated quantitative mapping of CE
level in human prostate tissues using hyperspectral stimulated
Raman scattering (SRS) microscopy that renders compositional
information for every pixel in the image. Specifically, hundreds of
SRS images at Raman shift between 1620-1800 cm-1 were taken,
and multivariate curve resolution algorism was used to retrieve
concentration images of acyl C=C bond, sterol C=C bond, andester C=O bond. Given that the ratio between images of sterol
C=C and ester C=O (sterol C=C/C=O) is nonlinearly proportional
to CE percentage out of total lipid, we were able to quantitatively
map CE level. Our data showed that CE level was significantly
greater in high Gleason grade compared to low Gleason grade,and could be a factor that significantly contributed to cancer
recurrence. Our study provides an opportunity towards moreaccurate PCa diagnosis and prediction of aggressiveness.

174

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Conference 10025:
Advanced Sensor Systems and Applications VII
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10025 Advanced Sensor Systems and Applications VII

10025-1, Session 1

Fiber Bragg grating-based temperature
sensor for neutral gas in capacitivelycoupled plasmas (Invited Paper)
Zigeng Liu, Daoman Han, Xinpu Zhang, Yongxin Liu, Wei
Peng, Younian Wang, Dalian Univ. of Technology (China)
In this paper, a fiber Bragg grating (FBG) has been utilizedin capacitively coupled plasmas (CCP) for thermometry ofneutral gas. The FBG was put into the single-frequency anddual-frequency power argon plasma respectively, which ismanufactured by ourselves. We studied the effects of highfrequency and low frequency power on radial distribution ofneutral gas temperature. The result shows that the neutral gas
temperature is higher than the room temperature by 10 ~ 120? in
CCPs and shows significant non-uniformity in space. The neutral
gas temperature increases with the increase of high frequency
power due to the enhancive collisions with Ar+ ion density. The
neutral gas heating is mainly caused by the elastic collisions of
Ar+ ion with neutral atoms when traversing the sheath region
after Ar+ ion gaining substantial energy. However, the presence oflow frequency power will decrease the neutral gas temperature.
Particularly, we eliminated the effect of iron bombardment on
neutral gas temperature by the temperature measurement ofplasma sheath near the electrode. The temperature sensitivity of
proposed FBG is 10.4pm/?, which is calibrate by a programmabletubular furnace. With features of immune to electromagnetic
interference, high precision, and spatial resolving power, the FBG
is a commendable candidate for CCP or other radio-frequency
plasmas thermometry in both laboratory and industry.

10025-2, Session 1

Simultaneous measurement of
temperature and strain based oncomposite long-period fiber grating
Chengguo Tong, Zhanjing Bao, Cuiting Sun, Xudong Chen,
Jiang He, Tao Geng, Harbin Engineering Univ. (China)
Long period fiber grating is a kind of transmission type opticalfiber grating. Due to the advantages such as low insertion
loss,wide bandwidth, low-level reflection, high sensitivity, low costand ease of compactness, LPFGs have been widely applied in
optical fiber sensing and optical fiber communication.
The Mode coupling of LPFG is the coupling between the fibercore mode and the cladding mode in the same transmission
direction.If the ordinary LPFG is combined with bitaper or taper,
we can effectively change the original LPFG’s transmission
spectrum to obtain the composite LPFG, which can stimulate
new resonant peaks in the original wavelength-dependenttransmission loss of the gtating basis, thus applying to the dualparameter simultaneously measuring field.
We report a novel all-fiber narrow-bandwidth intermodal
Mach–Zehnder interferometer (MZI) based on a long-period
fiber grating (LPFG) combined with a fiber bitaper.The LPFG iswritten by high-frequency CO2 laser pulses, and the bitaper isconnected in series with the LPFG, forming the Mach–Zehnderinterferometer (MZI). Experimental results indicate that the MZI
has good temperature sensitivity, The temperature sensitivity ofthe two loss peaks are 55.35pm/°C and 48.18pm/°C respectively.
The strain sensitivity of the two loss peaks are 3.35pm/?? and-4.925pm/?? respectively.By using the different temperature andstrain response characteristics of the loss peaks , the temperatureand strain measurement can be realized simultaneously. theReturn to Contents

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proposed device has good repeatability and stability, which
would be a promising candidate for precise dual-parameter
sensing application.

10025-3, Session 1

Temperature insensitive measurements ofdisplacement using fiber Bragg grating
sensors
Shuang Yang, Anhui Institute of Optics and Fine
Mechanics (China) and Univ. of Science and Technology
of China (China); Jun Li, Anhui Institute of Optics andFine Mechanics (China); Shengming Xu, Miao Sun, Anhui
Institute of Optics and Fine Mechanics (China) and Univ.
of Science and Technology of China (China); Yuquan Tang,
Anhui Institute of Optics and Fine Mechanics (China);
Gao Gang, Fengzhong Dong, Anhui Institute of Optics
and Fine Mechanics (China) and Univ. of Science andTechnology of China (China)
Optical fiber Bragg grating (FBG) displacement sensors play
an important role in various areas due to the high sensitivity todisplacement. However, it becomes a serious problem of FBG
cross-sensitivity of temperature and displacement in applications
with FBG displacement sensing. This paper presents a methodof temperature insensitive measurement of displacement via
using an appropriate layout of the sensor. A displacement sensor
is constructed with two FBGs mounted on the opposite surface
of a cantilever beam. The wavelengths of the FBGs shift with ahorizontal direction displacement acting on the cantilever beam.
Displacement measurement can be achieved by demodulating
the wavelengths difference of the two FBGs. In this case, thedifference of the two FBGs’ wavelengths can be taken in order
to compensate for the temperature effects. Four cantilever
beams with different shapes are designed and the FBG strain
distribution is quite different from each other. The deformationand strain distribution of cantilever beams are simulated by using
finite element analysis, which is used to optimize the layout of
the FBG displacement sensor. Experimental results show thatan obvious increase in the sensitivity of this change on thedisplacement is obtained while temperature dependence greatly
reduced. A change in the wavelength can be found with theincrease of displacement from 0 to 10mm for a cantilever beam.
The physical size of the FBG displacement sensor head can be
adjusted to meet the need of different applications, such as
structure health monitoring, smart material sensing, etc.

10025-4, Session 1

Sensing behavior of smart CFRP
embedded with FBG and its application instay cables
Feng Li, Xu Sun, Weigang Zhao, Shijiazhuang Tiedao Univ.
(China); Feng Shen, Nanjing Fenghui Composite Co., Ltd.
(China)A smart CFRP bar embedded with FBGs was developed throughan online manufacturing process. Sensing characteristics ofthe smart CFRP bar was investigated under static and fatigue
loading. A sensitivity coefficient of 1.19 pm/?? and a limiting
strain of about 8000 ?? were obtained. And the smart bar has
remained a good sensing behavior after 2 million cycles. Then,#PhotonicsAsia

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Conference 10025:
Advanced Sensor Systems and Applications VII
an application of the smart bar was carried out in the cable force
monitoring. Super tension test and field test were carried out on
the smart stay cable. The results show that the smart cable canrepresent the overall stress and successfully track its changes.

10025-5, Session 1

Tao Wang, Tiegen Liu, Kun Liu, Junfeng Jiang, Zhe Yu,
Meng Xue, Tianjin Univ. (China)
Tilted fiber Bragg gratings (TFBGs) have been demonstrated tobe accurate refractometers as they couple light from the fibercore to the cladding and TFBGs have been used in many field,
such as refractive detection, TFBG-SPR sensor and temperaturedetection. In our experiment, a tapered TFBG is manufactured bytapering the grating section of TFBG through a hydrogen-oxygen
flame brushing technique. The character of the tapered TFBG
was studied. The result shows that the tapered TFBG maintains
the similar feature as the original TFBG, they both have thecladding modes and core mode. The refractive sensitivity of thetapered TFBG and the original there is only a slight differencein the range of 1-1.4027. However, after tapered, not only the
Bragg wavelength of the TFBG shifts but also the full width
half-maximum (FWHM) of the core mode and cladding modeschange. The FWHM of the core mode of the tapered TFBG is265pm and the FWHM of the core mode of the original TFBG
is 120pm. The FWHM of the core mode of the tapered TFBG is
more than twice than the FWHM of the core mode of the original
TFBG. Thus we can use the low resolution spectrum analyzer inthe tapered TFBG refractive sensing system to get the similar
refractive sensitivity as in the TFBG refractive sensing systemwith high resolution spectrum analyzer. So the whole cost of thesensing system falls without sacrificing the feature of the system.

10025-6, Session 2

Interrelation of the effects caused by therotation of the whispering gallery modes
resonator (Invited Paper)
Anna D. Dmitrieva, Yurii V. Filatov, Egor V. Shalymov,
Vladimir Y Venediktov, Saint Petersburg Electrotechnical
Univ. “LETI” (Russian Federation)
Whispering gallery modes are specific eigenmodes of a field(sound, electromagnetic etc) inside an axially symmetricalresonators with smooth edges. ?ptical whispering gallery modes
resonators are characterized by unique properties: ultrahighquality factor, small amount of the modes and small size. It allows
to use them in compact high-precision measuring devices. In
particular these resonators can be used in the composition ofgyros. For today all researches, devoted to the application of
the whispering gallery modes resonators in gyros, deals onlywith one of induced by the rotation effects (Sagnac effect or the
influence of centrifugal forces on the resonator size). In this work
we study the interrelation of the effects caused by the rotation of
the whispering gallery modes resonator. Also in work is presented
the way of angular speed measurement of due to simultaneoususe of Sagnac effect and the influence of centrifugal forces on
the resonator size.

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Temperature effect on refractive index
sensing performance of a U-shape tapered
plastic optical fiber
Chuanxin Teng, Jilin Univ. (China); Ning Jing, North
University of China (China); Fangda Yu, Jilin Univ (China);
Jie Zheng, Jilin Univ. (China)

Optical fiber refractometer based on
tapered tilted-fiber Bragg grating

176

10025-7, Session 2·

A refractive index (RI) sensing probe based on a U-shape tapered
plastic optical fiber (POF) is proposed since the sensitivity
could be enhanced by cascading of bend and tapered POF
geometry. Recently, RI sensors based on POFs attract muchattention of researchers due to the POFs with some uniqueadvantages compared with glass optical fibers (GOFs), but thethermo-optic coefficient of POFs is an order of magnitude higher
than the one of GOFs. Therefore, the temperature influence to
the RI sensing probe was investigated experimentally in thispaper. It is found that the changes in light propagation loss inthe probe induced by temperature are of the same order ofmagnitude as those induced by measured RI changes, so thereis clearly a temperature dependence issue. The temperaturedependence loss and temperature dependence RI deviation of
the sensing probe were measured (at the wavelength of 635nm) in temperature of 10-60 °C over an RI range of 1.33-1.41.
By extracting pure temperature dependence of the sensing
probe alone, the influence of temperature to the sensor wascharacterized.

10025-8, Session 2

Thermal sensing performance of thenested fiber ring resonator
Changqiu Yu, Yundong Zhang, Yong Feng Wu, Hui Li, Tuo
Zhang, Yuan Ping, Harbin Institute of Technology (China)
We compare the temperature sensitivity between the nested
fiber ring resonator (NFRR) and the nested fiber ring resonator
coupled Mach-Zehnder interferometer (NFRRCMZI) undersame intensity scheme. Utilizing the transfer matrix theory, their
thermal performances were analyzed. Theoretical results indicatethat temperature sensitivity of the NFRR is almost twelve times
higher than that in NFRRCMZI with same parameters, hence
the complex MZI system can be avoided and the whole sensing
system will be more compatible.
Taking the U-shape feedback waveguide instead of the whole
resonator as the sensing element in NFRR structure, we canacquire arbitrary sensitivity by setting the feedback waveguidelength arbitrarily. It is more feasible in application for its simple
construction and integration. For R=5 the sensitivity and thedetection limit can achieve 23.19 /K and 0.000125 K, respectively.
The longer the feedback waveguide length, the higher sensitivity
and the narrower detection range we can obtain. And thedetection range is decided by the length of the feedback
waveguide: the detection sensitivity and detection range go
through a period when the feedback waveguide phase shiftby two pi. In practical applications, we can balance between
the sensitivity and the detection range and set the structure
parameters according to the requirements.
One of the advantages for the NFRR structure based sensor isthat its transmission spectrum would not shift horizontally undercertain shape. Therefore, the sensitivity of this sensor is not
limited by its optical quality factor. In this thesis, the transmission
spectrum of the sensor under different temperatures are
displayed to illustrate this unique property.

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Conference 10025:
Advanced Sensor Systems and Applications VII

10025-10, Session 2

The dispersion and spectrum output
characteristics in series-coupled doublering resonator
Dongyang Gao, Yundong Zhang, Chang Qiu Yu, Yong
Feng Wu, Hui Li, Ping Yuan, Harbin Institute of Technology(China)In this paper, we theoretically investigate the series-coupled fiber
double-ring resonator which have different perimeters, when
the double-ring resonator cannot be completely in resonancestate, the output characteristics and dispersion characteristics ofspectrum and its manifestations. we observe that light exhibits
different spectral output characteristics in the double-ringresonator, when the two rings’ length ratio?=1,1.1,1.5,2. Amongthem, ?=2 is particularly representative. When ?=2, there exist
two kinds of fixed pattern during the 2π period. When the valueof ?_2⁄π is even, the double-ring resonator produce traditional
symmetrical division resonance mode because they are incomplete resonance state ( ?_(i,i=1,2) is single-pass phase shift).
When the value of ?_2⁄π is odd, ?_1 is in complete resonance state
while ?_2 is in anti-resonance state, and it will generates periodic
strong absorption narrowband dip line shape with a larger grouprefractive index at the same time. When the second ring has thesame parameters, the group refractive index of the double-ringresonator whose length ratio is 2 which is two or three orders
higher than the single ring resonator. These results indicate that
we could improve the sensitivity of the double-ring resonatorbecause sensitivity is directly related to the group refractive.
The double-ring provides a nice platform and experimentalarchitecture for achieving high sensitivity of the spectrometer.
At the same time, it provides a possibility application ininterference and optical sensing fields for the high sensitivity ofthe spectrometer.

Distributed optical fiber vibration and acoustic sensors have
proven to be an efficient mean for interrogating a large numberof points along a single optical fiber, a capability which has
attracted substantial interest from industries involved in oil, gas
and structural health monitoring.
This paper presents a seismic wave detection system based on
fully distributed acoustic sensing (DAS). The architecture andprinciple of the system are introduced. Combined with ?-OTDR
and PGC demodulation technology, the system can detect andacquire seismic wave in real time. The system has a 3.05dB
flatness of frequency response from 5Hz to 1kHz, which withsampling interval of each channel of one meter on total sensing
distance up to 10 km.
Experiments are carried out to demonstrate the performanceof DAS system. Compared experiments with geophone arecarried out in laboratory, results show two waveforms coincideconsistently, and the correlation coefficient could be larger than
0.98. Other compared experiments are carried out in the fields,
results indicate that DAS system has a consistent time domain
and frequency domain response, and a clearer trail of seismic
wave signal as well as a higher signal to noise ratio.
The system we proposed can not only provide remarkable results,
but also reduce the complexity of the practical applications. Also,
DAS has many characteristics, like light weight, small volume,
low cost, high temperature and high pressure resistance, antielectromagnetic interference. This system uses an optical fiber tobe a sensing unit and exposes significant advantages in multichannel information acquisition and weak signal detection. Dueto its wideband frequency response and low manufacturing cost,the system is expected to be the next generation of oil and gas
exploration equipment.

10025-13, Session 310025-11, Session 3

A gain compensation method for the longrange distributed fiber disturbance sensor(Invited Paper)
Chunyu Ma, Tiegen Liu, Kun Liu, Junfeng Jiang, Liang Pan,
Miao Tian, Zhichen Li, Tianjin Univ. (China)
We proposed a gain compensation method to overcome theamplitude fading induced by the gain-bandwidth product (GBP)of the detector, which will seriously deteriorate the positioning
accuracy of the distributed disturbance sensor at a long sensing
range. To guarantee the performance of this method, we used
the time-frequency distribution of the interference signal todistinguish the normal signal and the one need to compensate. A
positioning measurement experiment using an asymmetric dual
Mach-Zehnder interferometric sensor (ADMZI) was carried out toverify the effectiveness of the proposed method. The experimentresult showed that the sensing range can reach 120km, which was
improved by over 40% compared to the traditional positioning
method without gain compensation.

10025-12, Session 3

Seismic Wave Detection System Based on
Fully Distributed Acoustic Sensing
Yue Jiang, Tuan Wei Xu, Shengwen Feng, Huang Jianfen,
Institute of Semiconductors (China); Yang yang, Instituteof Semiconductors, CAS (China); Guo Gaoran, Instituteof Semiconductors,CAS (China) and School of Traffic andReturn to Contents

Transportation, Shijiazhuang Tiedao University (China);
Li Fang, Institute of Semiconductors (China) and Chinese
Academy of Sciences (China)

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A study on frequency-shifted pulse lightstability control for DP-MZM in coherentOTDR
Wenjie Chen, Junfeng Jiang, Tiegen Liu, Kun Liu, Xuezhi
Zhang, Zhe Ma, Zhe Yu, Tianjin Univ. (China)
In digital coherent-OTDR disturbance sensing system, a dualparallel Mach-Zehnder modulator (DP-MZM) is employed tomodulate the signal light and to generate frequency-shifted
pulse light. However, the environment temperature strongly
influence the stability of the DP-MZM. To stabilize the quality of
the frequency-shifted pulse light, we proposed a bias control
method to keep the modulator at the optimum bias. This bias
control method search for the optimum bias by changing threebias voltages at the same time based on chaotic particle swarm
optimization algorithm. The experimental results show obvious
effect on locating the optimum bias voltages for the DP-MZM.

10025-14, Session 3

Spatial resolution enhanced distributed
disturbance fiber sensing system
employing modified TDE algorithm
Liang Pan, Tiegen Liu, Kun Liu, Junfeng Jiang, Chunyu Ma,
Tianjin Univ. (China)
A novel method to enhance the spatial resolution of distributed
disturbance fiber sensor is proposed in this paper. The proposed
scheme combines a high speed data acquisition system and a#PhotonicsAsia

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Conference 10025:
Advanced Sensor Systems and Applications VII
modified time delay estimate algorithm. The sensor performanceis significantly improved by eliminating the impact of fluctuationof the interference signal generated by the environment
disturbance. Theoretical analysis shows that with the proposed
spatial resolution enhanced method, the disturbance sensing
system is more suitable for various environments and provides
low uncertainty in long term operation with meter-scale spatial
resolution. Compared with the traditional time delay estimate
method in distributed disturbance sensing system based on thecriterion of spatial resolution, the positioning error of the sensor
using our proposed method has been reduced at least an orderof magnitude.

10025-15, Session 3

Study on error budget of large deployableoptical remote sensor
Yan Li, Xiaoli Chen, Beijing Institute of Space Mechanics
and Electricity (China)High resolution earth observation missions are based on large
aperture optical remote sensor (LDORS). Given that size, weight
and launch ability constraints, as well as cost consideration, thetraditional monolithic aperture optical system cannot satisfy
the requirements. The deployable optics is an effective way ofrealizing the large aperture remote sensing. The key point of
deployable optics is the primary mirror?The large primary mirror
is segmented and folded when is launched and stitched thetotal common phase mirror after the entry into orbit. With theadjustment of the adaptive optical system, the whole optics canachieve high imaging quality. Differently from traditional opticalremote sensor, the imaging quality of the deployable opticalsensors may be influenced by many kinds of error sources,
including the wavefront error (WFE) of the optical remote sensor
system, the error from vibration of the satellite platforms, etc. The
WFE of the optical remote sensor system include the engineeringfrom the fabrication processing, the position from deployingof segmented mirrors in orbit. In the process of feasibility
demonstration, the total WFE error budget of large deployableoptics plays a vital role in the general design of the remotesensor. According to results of calculation and iteration, in orderto ensure the optical performance of the remote sensor in orbit,
the WFE of the remote sensor is required to achieve ?/8rms?@?=632.8nm?, and the WFE of the optical system is required toachieve ?/10rms. In this paper, the error from optical systemdesign, which based the mission realization of optical fabricationand optical alignment.

10025-16, Session 3

Doppler Laser Radar for Range and Speed
Measurement of Road Targets
Yanfang Lin, Xuesong Mao, Jianchao Fang, Tao Zhang,
Wuhan Univ. of Science and Technology (China)
Laser radars measure target range and speed by two methods:
pulsed method or continuous wave (CW) method. CW method
modulates frequency of transmitting signal in the form of
triangular wave and gain range and speed by measuring
frequency difference between echo signal and local signal. The
method has an advantage of high precision due to the widebandof transmitting signal. However, the method is not adopted in
vehicle laser radar for road target sensing due to many factors
such as low transmitting peak power, multipath interference,etc. On the other hand, pulsed laser radars transmit short pulses
with large peak power, thus meet the requirement of sensing incomplex environments such as roads. It measures target range
by light flight time, while gain target speed by averaging range
differentiation. Although the pulsed method succeeds in road

178

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target sensing, it has large errors in the speed if time window for
averaging is short. In this paper, we propose a pseudo random
noise code modulated laser radar, which measures range andspeed by correlation function and Doppler frequency shift,respectively, to improve measurement precision and real time
property. For obtaining target range, we use the traditional
method of locating correlation peak of echo signals and local
modulating codes. In search of Doppler frequency, we propose
a novel method for solving spectrum of non-uniformly sampled
data. We verify the proposed method by theoretical analysis
and numerical simulations. The results show that our proposed
method works well for obtaining range and speed with highprecision.

10025-17, Session 4

Optical sensors interrogated by means ofspectral interferometry: noise sources andapproaches for resolution improvement
Nikolai A. Ushakov, Alexandr A. Markvart, Leonid B.
Liokumovich, Saint-Petersburg State Polytechnical Univ.
(Russian Federation)
One of the key factors, determining the resolution and dynamic
range of an optical sensor, is interrogation approach. Amongthe others, spectral interferometry (sometimes referred to as
white-light or low coherence interferometry), is very attractive
due to ability to provide measurements of absolute OPD value.
However, in practical situation, the measurement result contains
some erroneous component, which value is governed by specificcharacteristics of the interrogation unit.
In the presentation, the main error sources, stipulated by noises
and fluctuations in the interrogation hardware, will be considered.
It is shown that one of the most crucial error sources iswavelength scale jitter of the optical spectrometer, incorporated
in the interrogator. The main attention will be paid to approaches,enabling one to eliminate the influence of interrogator
fluctuations on the measurement results.
The first approach is suitable for use with multi-channelinterrogation devices, utilizing a tunable laser source, divided
into several (2-4) channels and single photodetector for eachchannel as a receiver. If sensing and reference interferometers
are switched to different optical channels of the interrogation
device, the readings of a reference interferometer can beused for compensating the errors in the readings of sensing
interferometer.
Another approach is suitable for use with all kinds ofinterrogation hardware and requires a single interferometer.
However, light diffraction and multibeam propagation must takeplace in the interferometer, so it must be an extrinsic Fabry-Perotor similar. In order to estimate and compensate the wavelengthscale jitter, the information about diffraction-induced phase shift
is used.

10025-18, Session 4

Fundamental theory and algorithm basedon spatial light modulator
Hua Liu, Science and Technology on Electro-Optic Control
Lab. (China)
The principle approach, modeling, and error analysis areanalyzed, and the system configuration based on SLM isadvanced in algorithm analysis. For to improve the resolutionof the imaging system, and achieve the theoretical limit, we
introduced that the core methodology, which is that in the deep
understanding and research of the photoelectric informationwww.spie.org/pa·

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Conference 10025:
Advanced Sensor Systems and Applications VII
control, the basic theory of the spatial light modulator and thealgorithm based on space-time adaptive system is discussed
deeply which used to the core of the photoelectric system
configuration by which key components applied to solve thecontrol function. This paper discusses the hardware system.
Usually, an SLM modulates the intensity of the light beam.
However, it is also possible to produce devices that modulate
the phase of the beam or both the intensity and the phasesimultaneously. Besides, the discuss includes the control on the
SLM for spatial information of the amplitude, phase, frequency,
polarization, and the intensity of energy research. A typical modelis used to illustrate the feasibility, and the criteria is developed.
The technology principle of super resolution restructure fromthe point of view on theory and engineering. Three kinds ofrestructure technologies, that prototype, micro scanning andsub pixel are described, and how to decrease their shortcomings
are discussed in detail. Furthermore, to improve the band widthby reconstruction without the spectral alias in super resolution
technologies, a new coding technology combining a opticalencoding and the sub pixel is proposed. With the global method,
simulation results show that the system can meet the application
requirements in MTF, REA, RMS and other related criteria.

10025-19, Session 4

Multi-sensor data fusion and estimation
with poor information based on bootstrapfuzzy model
Yanqing Wang, Weihu Zhou, Academy of OptoElectronics, CAS (China); Zhongyu Wang, BeiHang Univ.
(China)Multi-sensor data fusion and estimation with poor information is
a common problem in the field of stress measurement. Small anddistribution unknown data sample obtained from multi-sensor
makes the data fusion and estimation much difficult. To solve
this problem, a novel bootstrap-fuzzy model is developed. Thismodel is different from the statistical methods and only needs alittle data. At first, the limited stress multi-sensor measurement
data is expanded by the bootstrap sampling. Secondly, the data
fusion sequence is constructed by the bootstrap distribution.
Finally the true value and the interval of the stress multi-sensor
measurement data are estimated by the fuzzy subordinate
functions.
The method involves two parts: one is the bootstrap method
for multi-sensor data fusion which expands the data sample andresamples the very few original sensor measurement data greatly;
the other is the fuzzy subordinate functions which obtain theestimated true value and interval of the sensor data successfully.
The experimental results show that the full conditions of themeasurement parameters can be attained totally throughbootstrap-fuzzy model. So the failing and false data predictions
can be avoided. Referring to the stress measurement system,bootstrap-fuzzy model can be employed to increase themeasurement confidence, reduce the ambiguity, improve thereliability, and boost the accuracy. Moreover, bootstrap-fuzzymodel can be considered as complementary to the existing data
fusion theory in use. The accuracy of the estimated interval canreach 85%. Therefore, the effect of the proposed bootstrap-fuzzymodel is validated.

10025-20, Session 4

Tomographic reconstruction using 4 views
and tunable diode laser
Osborn Oliver M., Muruganandam T.M., Indian Institute ofTechnology Madras (India)

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Tomographic Reconstruction Using 4 Views And Tunable Diode
Laser: Called the ‘Reduced Back Projection’ technique(or RBP),
this new method is an improvement on existing tomographic
reconstruction techniques in the field of laser diagnostics in a
combustor exhaust. The highlight of this technique is the useof only FOUR views to create a planar reconstruction frompath averaged data which is obtained from water absorption
spectroscopy in the IR region near 1377nm. Water sensitive
wavelengths are generated by using a Tunable Diode laser
working in the IR region. For the purpose of this paper, work
is done on a plane in the exhaust of a burner perpendicular
to the flame direction. The geometry of the burner decides
the distribution of water molecules in the interrogation plane.
This technique is based on the back projection method but
has been extensively modified and improved to work with justfour views instead of the hundred or so views used in medical
tomography. Simulations have been run to check the working of
the new technique, and compared with other current methods
in tomography (SART, back projection, etc.). Preliminary
experimentation over a simple two burner geometry has been
performed. In both simulation and experiment, the RBP technique
has yielded better results than existing methods by virtue ofthe new method being able to capture features where the othermethods have failed. Thus, RBP can be used in situations where
there are constraints in resources, time and space.

10025-9, Session Post

Changes of shape of the whispering
gallery modes resonators due to their
movement in inertial space
Yurii V. Filatov, Alexander S. Kukaev, Egor V. Shalymov,
Vladimir Y. Venediktov, Saint Petersburg Electrotechnical
Univ. “LETI” (Russian Federation)
The whispering gallery modes resonators are axially symmetricalresonators with smooth edges, supporting the existence of thewhispering gallery modes. In recent years, optical whispering
gallery modes resonators are attracting ever-growing interestof the scientific community. It is connected with their uniqueproperties: ultrahigh quality factor, small amount of the modes
and small size. For today various types of such resonators weredeveloped, namely the ball-shaped, tor-shaped, bottle-shaped,
disk-shaped etc. The movement of whispering gallery modes
resonators in inertial space causes changes of their shape.
Optical methods allow to register these changes with highprecision. It can be used for measurement of angular velocities
and linear accelerations in inertial orientation and navigation
systems. In this work we performed a multiphysical simulationin OOFELIE::Multiphysics software to investigate changes ofshape of the whispering gallery modes resonators due to their
movement in inertial space.

10025-38, Session Post

A new vibration monitoring system basedon fiber-optic micro-cantilever
Shengming Xu, Anhui Institute of Optics and Fine
Mechanics (China) and Univ. of Science and Technology
of China (China); Jun Li, Anhui Institute of Optics andFine Mechanics (China); Shuang Yang, Miao Sun, Anhui
Institute of Optics and Fine Mechanics (China) and Univ.
of Science and Technology of China (China); Yuquan Tang,
Anhui Institute of Optics and Fine Mechanics (China);
Fengzhong Dong, Anhui Institute of Optical and Fine
Mechanics (China) and Univ. of Science and Technology ofChina (China)#PhotonicsAsia

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Conference 10025:
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slow search speed and poor search results. This experiment deals
with images and programs the motor drive under the compilingenvironment of Matlab and Visual Studio and establishes thevisual 2.5D grid map. Finally it plans a global path for the mobile
robot according to the ant colony algorithm. The feasibility andeffectiveness of the system are confirmed by ROS and simulation
platform of Linux.

This paper mainly introduces a new vibration monitoring
based on fiber optic micro-cantilever. Such sensor is typicallyconstructed directly onto the endface of fiber and consists of acleaved facet which is sensitive to vibration.
Compared with the traditional Fabry-Perot interferometer, forexample, the sensor consists of an optical fiber and sensitive
diaphragm, or the sensor constructed on two fiber endfaces.
Optical fiber cantilever based structure is capable of measuring
wider range of vibration signal with higher sensitivity.
Fiber endface and micro-cantilever is composed of Fabry-Perotcavity as a sensing section of the sensor, the external signal
is transmitted to the sensor, which causes the vibration of the
micro-cantilever, which changes the length of the Farby-Perotcavity. The information of the external vibration signal can beobtained by using the 3 wavelength interrogation algorithm.
The mechanical vibration characteristics of the micro-cantileverwith different materials and the influence of the reflectivity
change caused by the coating on the surface of the microcantilever are simulated and analyzed. The resonance frequency
range of the cantilever beam varies with different material,
therefore, the detected frequency range of the system is limited.
The demodulation precision of the system can be improved bycoating the cantilever surface with different material. Based on
the simulation results, the appropriate cantilever beam structure
and coating materials are selected to build optical fiber microcantilever vibration detection system. A relatively flat frequency
response is achieved from 1 kHz to 20 kHz. Compared with thetraditional microphone, the sensitivity of the proposed structure
can be improved through the selection of suitable materials.

10025-39, Session Post

The research of autonomous obstacle
avoidance of mobile robot based on multisensor integration
Ming Zhao, Junqin Lin, Baoling Han, Beijing Institute ofTechnology (China)
The object of this study is the bionic quadruped mobile robot.
The study has proposed a system design plan for mobile robot
obstacle avoidance with the binocular stereo visual sensor andthe self-control 3D Lidar integrated with modified ant colony
optimization path planning to realize the reconstruction of theenvironmental map. Because the working condition of a mobile
robot is complex, the result of the 3D reconstruction with asingle binocular sensor is undesirable when feature points are
few and the light condition is poor. A Lidar sensor can detect
the information of obstacles well because it is an active probe,
so it will not be disturbed by external environment factors
easily. Therefore, this system integrates the stereo vision sensor
blumblebee2 and the Lidar sensor together to detect the cloud
information of 3D points of environmental obstacles. What’smore, this study has designed a fast 3D scanning Lidar system
which consists of a 2D Lidar, a pitching mechanical device driven
by a stepper motor and its relevant control units. This design will
satisfy the reconstruction result with low cost and high precision.
This paper proposes the sensor information fusion technology torebuild the environment map.
Firstly, according to the Lidar data and visual data on obstacle
detection respectively, and then consider two methods
respectively to detect the distribution of obstacles. Finally fusing
the data to get the more complete, more accurate distributionof obstacles in the scene. Then the thesis introduces ant colonyalgorithm. It has analyzed advantages and disadvantages of
the ant colony optimization and its formation cause deeply,
and then improved the system with the help of the ant colony
optimization to increase the rate of convergence and precision of
the algorithm in robot path planning. Such improvements andintegrations overcome the shortcomings of the ant colony
optimization like involving into the local optimal solution easily,
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10025-40, Session Post

Thin-core fiber modal interferometer with
polyelectrolyte membrane for dissolved
ammonia sensing
Xinyue Huang, Xueming Li, Yu Li, Huifei Chen, Jianchun
Yang, Chongqing Univ. (China)
With the unhealthy development of the industry and agriculture,
the pollutant emissions were increased dramatically, which has
caused serious pollution to the aquatic environment. Ammonia
nitrogen is an important indicator among water environmental
monitoring parameters. Thus, a simple and portable sensor isdesirable to achieve sensitive detection of ammonia nitrogen.
The construction of poly(acrylic acid) (PAA) and poly(allyaminehydrochloride) (PAH) films on the side surface of the thin-core
fiber modal interferometer (TCFMI) using the layer-by-layer(LbL) self-assembly technique for dissolved ammonia detection
is presented and investigated in this paper. The sensor is madeby inserting a small section of thin-core fiber to the standard
single mode fiber (SMF). A beam propagation method (BPM) is
employed for numerical simulation and design of the proposed
TCFMI. Based on the simulation results, a TCFMI with a length of
2 cm of thin-core fiber is fabricated and experimentally studied.
The fabricated sensing nanocoating is characterized by surface
profiler, and scanning electron microscopy (SEM). The sensing
capability of TCFMI with PAH/PAA film is demonstrated by
optical spectrum analyzer (OSA). PAA could act as a receptor
for binding of amine compounds, which would induce changes
in the film properties, thus influencing the transmission spectrumof the TCFMI. Experimental results show that the characteristic
wavelength shift has an approximately linear relationship withthe change of the ammonia concentration. The optimal detection
range of this sensor is around 1-250 ppm. The experimental
results fit well with the numerical simulation results.

10025-41, Session Post

Design of a micro-uncooled infrared
imaging system based on VOx IRFPA
Dingchao Xie, Beijing Institute of Technology (China);
Youchun Song, Kedun Science and Technology Co. Ltd.
(China); Beiyan Liang, North GuangWei Technology Inc.
(China); Qiang Wu, Kedun Science and Technology Co.
Ltd. (China); Yue Yang, North GuangWei Technology
Inc. (China); Yufei Zhao, Yong Song, Beijing Institute ofTechnology (China)
Compared with the infrared focal plane array (IRFPA) based on
amorphous silicon (?-si), IRFPA based on vanadium oxide (VOX)
has the advantages of big temperature coefficient of resistance,
low noise and so on. Therefore, it is believed that VOX IRFPA has
important application in both military and civil field. On the other
hand, generally, the infrared imaging system based on VOX IRFPA
has the disadvantages of high cost and big size, which limits its
application in the field of civil consumption.
In this paper, a design of a micro uncooled infrared imaging
system based on VOx IRFPA is proposed, of which a low cost
384?288 VOX IRFPA produced by China North Guangwei

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Conference 10025:
Advanced Sensor Systems and Applications VII
Technology, Inc. is used for photoelectronic conversion, andthe parameter configuration and consistency correction are
implemented by using a low-cost FPGA (Altera cyclone IV
EP4CE55).
In this paper, firstly, the hardware designs of the proposedsystem is discussed, which includes the system structure, VOX
IRFPA module, drive and signal output module and the signal
processing module based on FPGA. Secondly, the designs of
the configuration program as well as the consistency correction,
image enhancement algorithm are also introduced. Finally,
experiments were carried out to verify the validity of thedeveloped models and the whole infrared imaging system, theexperimental results indicated that our work will help to promote
the application of infrared imaging technology in the field ofcivil consumption, such as security monitoring, temperaturemonitoring and smart home, etc.

10025-42, Session Post

Medical respiratory monitoring sensor
based on optical fiber microbend loss
Yong Zhao, Northeastern Univ. (China)
In this work, a medical respiratory monitoring sensor basedon the microbend effect of optical fiber on light transmission
is proposed. The microbend effect of multimode optical fiber
is analyzed theoretically using optical theory. A respiratory
signal modulator with a “sandwich” microbender structure isdesigned enabling the noninvasive real-time monitoring. In vitro
testing showed that the proposed sensor has excellent following
characteristics and can automatically discern respiratory
condition, the signal-to-noise ratio can be better than 28dB.
In this paper, we proposed a medical respiratory monitoring
sensor based on the microbending effect of optical fiber. The
model and presumption are proved feasible in principle. The
sawtooth structure makes the respiratory signal modulator easy
for fabrication and low cost, the respiratory signal modulator’s
design parameter is optimized by deduction and simulation. The
trails conducted on human showed our sensor was able to detect
breathing rate efficiently. This study has achieved certain result
by observing the breathing waveforms in different subjects at
different frequency, and at the end the difference between themonitored respiratory rate and the frequency is less than 1 time
per minute. It has good accuracy with multiple measurements.
However, there still are some deficiencies needing to be
improved. For the noise, with further improvement to the device,
the signal-to-noise ratio can be up to 28dB. And texture of theused materials, location and manner of the measuring person will
maybe have influence on the measurement results.

10025-43, Session Post

Development of fiber optical temperature
sensor based on fluorescence lifetime
Yong Zhao, Northeastern Univ. (China)
In order to realize the on-line monitoring of high voltage
switchgear’s contact temperature, this paper puts forwarda kind of optical fiber temperature sensor based on
fluorescence lifetime. It can be applied to measurement instrong electromagnetic, strong corrosion and other harshenvironment by using the approximate linear relationshipbetween temperature and fluorescence lifetime of rare earth
fluorescent material. A small volume, long service life, strong
anti-jamming capability of fluorescence temperature sensor was
designed by matching rare earth fluorescent material with longer
fluorescent lifetime with tee optical coupler. The experimental
results show that this method has a high measuring precision
within the scope of 0-90?, and in the case of good calibration,

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temperature measurement channel can meet the requirements ofmeasurement error (±0.1 ?).

10025-44, Session Post

Research on high-temperature sensing
characteristics based on modular
interference of single-mode multimodesingle-mode fiber
Zhaozhuang Peng, Li Wang, Beijing Univ. of Technology(China)Application of high temperature fiber sensing system is very
extensive. It can be mainly used in high temperature test
aerospace, such as, materials, chemicals, and energy. In recent
years, various on-line optical fiber interferometric sensors basedon modular interference of single-mode-multimode-singlemode(SMS) fiber have been largely explored in high temperature
fiber sensor. In this paper we use the special fiber of a polyimide
coating, its sensor head is composed of a section of multimodefiber spliced in the middle of Single-mode fiber. When the lightis launched into the multimode fiber(MMF) through the lead-in
single-mode fiber(SMF), the core mode and cladding modes
are excited and propagate in the MMF respectively. Then, at the
MMF-SMF spliced point, the excited cladding modes coupledback into the core of lead-out SMF interfere with SMF coremode. And the wavelength of the interference dip would shiftdifferently with the variation of the temperature. By this mean,
we can achieve the measurement of temperature. In theory, we
can obtain multimode optical fiber transmission of light waves
through simulation. The experimental results also show that thefiber sensor based on SMS structure has a highly temperaturesensitivity. With the temperature increasing, the interference dipslightly shifts toward longer wavelength and the temperaturesensitivity coefficient is 0.0205nm/?. With high sensitivity, simple
structure, immunity to electromagnetic interferences and a good
linearity of the experimental results, the structure has an excellent
application prospect in engineering field.

10025-45, Session Post

Optical fiber sensing parametermeasurement using wavelength divisionmultiplexer and FBG
Huanhuan Yan, Beijing Univ. of Technology (China)
In this experiment, the optical parameters of optical fiber sensing
measurements with the wavelength division multiplexer (WDM)
and Fiber Bragg grating have obtained in temperature-controlled
cabinet. The wavelength division multiplexer device not only
make different wavelength illuminant input at the same time bepossible, but also can achieve multi-channel output based on
the feature of WDM. We design and put forward a new method
which can realize various parameters measured at the sametime, such as temperature and the refractive index or stressmeasurement. In addition, it can measure the same parameterswith different wavelengths of laser at the same time. The contrast
analysis results of different wavelengths of illuminant on the same
parameter sensitivity and reliability of the measurement will use
to provide reference to design the same illuminant with different
parameter measurements.

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Conference 10025:
Advanced Sensor Systems and Applications VII

10025-46, Session Post

10025-48, Session Post

Hybrid MEFPI/FBG sensor for
simultaneous measurement of ultrasoundand magnetic field

Porous silicon-based two-dimensional
photonic crystal for biochemical sensing
applications

Yong Zhao, Northeastern Univ. (China)

Jiaqing Mo, Xinjiang Univ. (China) and College ofInformation Science and Engineering (China); Xiao-yi Lv,
Xi’an Jiaotong Univ. (China)

Simultaneous physical parameters measurement has been thefocus of the research works and problem in physics, which isan efficient method of measurement, and has many additional
advantages such as small volume, decreasing transmission
data, and low cost. In this Paper, A hybrid fiber-optic sensor
consisting of a micro extrinsic Fabry-Perot Interferometer(MEFPI) and an etched fiber Bragg grating (FBG) is proposed,
which can measure ultrasonic and magnetic field simultaneously.
The measurement of magnetic field is realized by the etched
FBG, which is sealed in a capillary with ferrofluids. The resonant
wavelength of FBG shifts when the magnetic field which isperpendicular to the axis of FBG changed. Simulation prove thatthe center wavelength of etched FBG shifts to longer wavelengthwith the increase of ambient refractive index, and it shifts sharply
when the ambient refractive index near 1.460, in addition, theFBG with small diameter will be more sensitive to magnetic field,
these are also confirmed in experiment. The MEFPI sensor thatis prepared through welding a short section of hollow core fiber(HCF) with single-mode fiber (SMF) is effective for ultrasonicwave detection. The length of FPI cavity can be controlled
precisely by a high precision optical fiber cutting platform. The
shorter the cavity length has the higher strain sensitivity andthe larger free spectral range (FSR), which is advantageous forsensing applications. The experiment shows that the etched FBG
has a reversible response on magnetic fields under 21 mT with ahigh sensitivity, and the measurement results of ultrasonic-wave
by the MEFPI sensor agree well with those by the piezoceramic
needle hydrophone; moreover, the detections of ultrasonic andmagnetic field have little effect on each other, hence it is feasible
to measure ultrasonic and magnetic field simultaneously basedon hybrid MEFPI/FBG sensor.

10025-49, Session Post

Temperature robustness of reflecting
multichannel all-fiber current sensor basedon time-division multiplexing
Junzhen Jiang, Fujian Normal Univ. (China)

10025-47, Session Post

Modeling of a long-period fiber-optic
grating-assisted surface plasmon
resonance refractive index sensor
Wenhua Wang, Weina Wu, Jiang Huang, Xiuyun Tian,
Xianxiang Fei, Guangdong Ocean Univ. (China)
A fiber-optic refractive index sensor assisted surface Plasmon
resonance of metal dielectric layer around a long-period gratingwith hollow fiber core has been proposed and comprehensively
analyzed. Its operation principle is based on the efficientenergy transfer between the fiber waveguide mode and theco-directional surface Plasmon waves excited with a long-period
fiber-optic grating properly designed by the light refracted
through the interface between the waveguide area and the metal
dielectric film. The long-period fiber-optic grating is fabricated ona waveguide area of a specially designed fiber-optic with hollow
fiber core. Simulations have been carried out in coupled mode
theory of fiber-optic gratings in the wavelength ranges from 1500
to 1600nm, and for sensing characteristics of refractive index.
Unlike a previous proposed short-period fiber Bragg grating
fabricated on this kind of fiber, the refractive index sensitivity of
the long-period fiber-optic grating is 15 times higher than thatof the fiber Bragg grating. The proposed long-period fiber-optic
refractive index sensor assisted surface Plasmon resonance iscompact, light weight, and highly sensitive with a large sensing
range.

182

In recent years, various novel porous silicon-based photonic
devices have been exploited for the detection of chemicaland biological species, including grating waveguide, resonant
photonic structures, and diffraction gratings. We have designed
and characterized a two dimensional photonic crystal based on
porous silicon with a defect embedded in its middle as an opticalsensor for sensing of various chemical and biological species.
The two-dimensional photonic srystal is composed of squarelattice dielectric cylinders made of porous silicon.Simulations
are carried out by changing the refractive index, which is due tothe binding of biological molecules on the porous silicon porecan increase the refractive index of porous silicon. The change ofthe refractive index of the porous silicon caused by the entry of
the biomolecule, which caused the change of the field strengthof two dimensional photonic crystal.The theoretical reflectancesof PSi-based two dimensional photonic crystal throughout the
paper were calculated using the commercial codes Comsol
5.0.This novel porous silicon based two dimensional photonic
crystal opens the door for design all-silicon sensor for sensingof various chemical and biological species and can also be good
applied in narrow bandpass filter.

SPIE Photonics Asia·

ALL-FIBER current sensors (AFCSs) have attracted considerable
attention for more than 20 years because of their simple
configurations, good optical integration, and outstanding
flexibility compared with other optical current sensors such as
bulk-glass current sensors or space coupling optical current
sensors. However, some obstacles hinder the application of the
AFCS. Among them, their temperature sensitivity are a crucial
weakness. High sensitivity to temperature will disturb current
measurement, reduce the current sensitivity, and make it difficult
to apply the AFCS in actual environments.
In 2014, we reported temperature and vibration robustness ofreflecting all-fiber current sensor using common single-node
fiber. A theoretical analysis shows that the temperature sensitivityof the AFCS based on a fiber mirror and ortho-conjugate
retroreflector [(OCR), 90°Faraday rotating mirror] are almost
entirely independent of the birefringence condition of the fiber.
In order to improve the sensor efficiency and reduce cost, we
proposed a temperature robustness of reflecting multichannel
all-fiber current sensor based on the principle of time-divisionmultiplexing. The multichannel all-fiber current sensor useda sensor to synchronously monitor the currents at manydifferent points. The multichannel fiber sensor signals were thenmultiplexed using fiber-delay coils. Time-division multiplexing
can be conveniently implemented to increase the amount of
information gained about the sensor. Since a multichannel fiber
current sensor needs only a pulse laser, detector, and dataprocessing system, the cost can be kept low relative to more
complex sensors.

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Conference 10025:
Advanced Sensor Systems and Applications VII

10025-50, Session Post

Demonstration of distributed fiber-optic
temperature sensing with PM fiber using
polarization crosstalk analysis technique
Hongxin Su, Ziwei Zhao, Ting Feng, Dongliang Ding,
Zhihong Li, X. Steve Yao, Hebei Univ. (China)
Polarization crosstalk is a phenomenon that the powers of two
orthogonal polarization modes propagating in a polarization
maintaining (PM) fiber couple into each other. Because there
is certain mathematical relationship between the polarization
crosstalk signals and external perturbations such as stressand temperature variations, stress and temperature sensing
in PM fiber can be simultaneously achieved by measuring
the strengths and locations of polarization crosstalk signals.
In this paper, we report what we believe the first distributed
temperature sensing demonstration using polarization crosstalk
analysis in PM fibers. Our experimental setup was composedof a polarization crosstalk analyzer (PXA), a length of PM fiberand a temperature control chamber. The PXA can obtain thelocations and values of temperature variations along the PM
fiber by measuring the spacing changes between two crosstalkpeaks caused by temperature induced birefringence change in
PM fiber. The experimental results show that the temperaturesensing coefficient is approximately ?0.76 ?m/(?•m), whichmeans that the spacing between two crosstalk peaks induced at
two locations changes by 0.76 ?m when the temperature changes
by 1 ? over a fiber length of 1 meter. Sub degree temperature
resolution with center meter spatial resolution with over 5 km
range is expected with this method. Furthermore, the proposed
distributed sensing system can simultaneously measure thetemperature and stress/strain with high precision. As a new typeof distributed fiber temperature sensing technique, we anticipate
that our method will find broad applications in the near future.

10025-51, Session Post

Surface plasmon resonance sensor basedon grapefruit-type photonic crystal fiberwith silver nano-film
Lei Zhang, Hebei GEO Univ. (China); Yibo Zheng, Hebei
GEO Univ. (China) and Tianjin Univ. (China); Yuan Wang,
Hebei GEO University (China); Jianquan Yao, Tianjin
University (China)
In this article, surface plasmon resonance sensors based on
grapefruit-type photonic crystal fiber (PCF)with different silver
nano-film structure have been analyzed and compared though
the finite element method (FEM) by using COMSOL Multiphysics
software. The regularity of the resonant wavelength changing
with refractive index of the sample has been numericallysimulated. The surface plasmon resonance (SPR) sensing
properties have been numerically simulated in both areas ofresonant wavelength and intensity detection. Numerical results
show that excellent sensing characteristics of the silver nanowires
filling structure can be achieved as the thickness of the nanofilm
is 30nm, with both spectral and intensity sensitivity in the rangeof 6?10-5~7?10-5RIU.

10025-52, Session Post

Photonic crystal fiber sensor based on
surface-enhanced Raman scattering for
explosives detection
Chuanyi Tao, Rong Chen, Chongqing Univ. of Technology

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Follow us on:(China); Jingke Li, Chongqing Medical and Pharmaceutical
College (China)
The detection of explosives and their residues is of great
importance in antiterrorism, public health, and homeland
security applications. One of the most common constituentsin these explosives is 2,4,6-trinitrotoluene (TNT) and its byproduct, 2,4-dinitrotoluene (DNT). The vapor pressures ofmost explosive compounds are extremely low and attenuationof the available vapor is often great due to diffusion in theenvironment, making direct vapor detection difficult. In thispaper, we report fast and sensitive detection of DNT and TNT
vapors using gold nanoparticles (Au-NPs) as the SERS substrate.
The Au-NPs are formed a monolayer on the air channels in aphotonic crystal fiber (PCF) through polymer-mediated selfassembly. The SERS substrate such prepared has high SERS
enhancement, high affinity towards explosive vapor, and rapid
response to the explosive adsorption/desorption. The PCF
SERS probes can achieve higher sensitivity than that obtainableby directly focusing the excitation laser light into the sample
without using any fiber probes (direct sampling). The higher
sensitivity achieved by the PCF SERS probe is shown to be
due to the confinement of the excitation light and the Raman
scattered light, as well as the analyte, inside the air channels that
increased the effective interaction volume. This work will lead tothe development of fast and highly sensitive optical fiber SERS
devices for explosive molecules identification and monitoringoutside the laboratory. The sensor device therefore is capable offield operation.

10025-53, Session Post

Torque transducer based on fiber Bragg
grating
Tao Li, Shu Jiang, China Shipbuilding Industry Corp.
(China); Jiang Li, No. 704 Institute, China Shipbuilding
Industry Corporation (China); Jiejun Lin, Hongli Qi, China
Shipbuilding Industry Corp. (China)
In order to obtain the accurate torque measurements in harshcondition, such as marine environment, a torque transducer
based on fiber Bragg grating is proposed in this paper. According
to its optimized elastomer design and fiber Bragg grating
patching tactics, the new proposed torque transducer realizes
automatic compensations of temperature and bending moment
which avoids influences from environment. The accuracy andstability of the torquetransducer, as well as its underwater
performance are tested by loading tests both in air and inunderwater environment, which indicate the designed torquetransducer is not only able to realize high-accurate and robust
measurements, but also can be applied in torque sensing in harshenvironment. We believe the proposed design detailed illustrated
in this paper provides important reference for studies andapplications on torque measurements in marine environment.

10025-54, Session Post

A spherical-structure-based fiber sensor
for measuring simultaneous measurementof both ammonia gas concentration andtemperature
Wei Han, Dejun Liu, Fangfang Wei, Dublin Institute ofTechnology (Ireland); Qiang Wu, Northumbria Univ.
(United Kingdom); Gerald Farrell, Yuliya Semenova,
Xiaokang Lian, Dublin Institute of Technology (Ireland);Lei Sun, Beijing Univ. of Posts and Telecommunications(China)#PhotonicsAsia

183

Conference 10025:
Advanced Sensor Systems and Applications VII
A novel fiber sensor for simultaneously measuring both theammonia gas concentration and temperature is proposed. The
sensor is fabricated from two sections of single-mode fiber
which are cleaved and then a fusion splicer is used to fabricate
the spherical-shape structures at the end facets. The fusion arc
is used to soften the glass which naturally assumes a sphericalshape due to surface tension. A short section of multimode fiber
is then fusion spliced with the two spherical-shaped ends of thesingle mode fibers so both the core modes and the cladding
modes of the multimode fiber are excited to create two kindsof interference dips: One is created by core modes only which
is not sensitive to ammonia gas and the other is created by
the coupling of the core mode and cladding mode which issensitive to ammonia gas. Silica sol-gel was prepared and coatedon the fiber surface as a sensing layer for detecting ammonia
gas concentration. The experiment results show that the twodips have linear wavelength shift responses but with different
sensitivities to ammonia gas concentration (5.03e-4 nm/ppm
for dip1 and -2.5e-5 nm/ppm for dip2) and temperature (0.0067
nm/ºC for dip1 and 0.0149 nm/ºC for dip2. By constructing
a wavelength shifts matrix for the two dips vs. ammonia
gas concentration and temperature, both the ammonia gas
concentration and temperature can be measured simultaneously.

10025-55, Session Post

A refractive index sensor based on taper
Michelson interferometer in multimodefiber
Xinghu Fu, Guangwei Fu, Wa Jin, Weihong Bi, Yanshan
Univ. (China)
Normally, the liquid concentration corresponds to different
refractive index. By measuring the refractive index of liquid,its concentration can be obtained indirectly. With the wide
application of various optical fiber, the optical fiber refractive
index sensor has become one of research hotspots. Currently
reported fiber refractive index sensors have a lot of kinds, such as
refractive index based on fiber Bragg grating, long period fiber
grating, the structure of cascaded single-mode and multimodefiber, and so on. Therefore, optical fiber sensor has the very
good development prospect in the field of liquid refractive
index detection. Especially, tapered fiber have many advantages
including high sensitivity, small size and simple structure. Sp it
is used to measure the liquid refractive index more extensively.
By fused tapering or corrosion technology, the internal structure
and transport properties of multimode fiber is changed, atapered multimode fiber sensor can be obtained. In this paper, arefractive index sensor based on taper Michelson interferometerin multimode fiber is proposed. The Hydrofluoric acid corrosion
processing is studied in the preparation of single cone multimodeoptical fiber sensor and the taper Michelson interferometeris fabricated by changing corrosion time. The relationshipbetween fiber sensor feature and corrosion time is analyzed. For
different taper Michelson interferometer in multimode fiber, therefractive index sensing property is presented in experiment. The
experimental results show that there is a blue shift phenomenon.
Namely, the interference spectrum shift in the direction of shortwave with the increase of the refractive index. The refractive
index sensitivity can reach 115.8008 nm/RIU. Thereby, it can beused in detecting the refractive index in different areas including
the environmental protection, health care and food production.

10025-56, Session Post

Research into multispectral TDI-CCD
imaging and fusion technology
Da He, Yong Jian Zhou, Lin Chang Liu, China Electronics

184

SPIE Photonics Asia·

Technology Group Corp. (China)
A scanning imaging system based on 6144?96 multi-band fivecolor TDI-CCD was built, which is featuring Real-time imaging
capability with high sensitivity and high dynamic range in multispectral bands for the same targe.In this paper, the respective
pixel topology for five TDI-CCD was obtained on the basis of
their spatial relationship in five bands. Finally, high resolution
gray-scale image and color image reconstruction for the scenic
target were achieved by multi-Spectral fusion Algorithms.

10025-57, Session Post

Detection of nitrogen dioxide by CW
cavity-enhanced spectroscopy
Guo Jie, Yu ZhiWei, Hangzhou Zetian Technology Co., Ltd.
(China)In urban areas, high NO2 concentrations have significant effects
on human health, which also lead to photochemical “smog”
formation, and the visibility will decrease due to secondary
aerosol formation. Therefore, NO2 concentration is one of theimportant monitoring parameters of air monitoring station. In
the paper, an accurate and sensitive system was used to monitor
the ambient atmospheric NO2 concentrations. This systemutilizes cavity attenuated phase shift spectroscopy(CAPS), a
technology related to cavity ring down spectroscopy(CRDS).
Advantages of the CAPS system include such as: (1) cheap andeasy to control the light source, (2) high accuracy, and (3) low
detection limit. This work aims to provide an initial validationof the CAPS NO2 concentrations monitor in laboratory andfield environments. The minima (~0.1 ppb) in the Allan plotsshow the optimum average time(~100s) for optimum detection
performance of the CAPS system. Over a 5-day-long periodof the ambient atmospheric NO2 concentrations monitoring, acomparison of the CAPS system with an extremely accurate andprecise chemiluminescence-based NOx analyzer showed that
the CAPS system was able to reliably and quantitatively measureboth large and small fluctuations in the ambient nitrogen dioxide
concentration. Moreover, the nitrogen dioxide concentrations
from the CAPS system are highly correlated(0.9) with thestandard NOx analyzer.

10025-58, Session Post

Remote canopy hemispherical image
collection system
Xuefen Wan, North China Institute of Science andTechnology (China); Bingyu Liu, Northeastern University(China); Yi Yang, Donghua Univ (China); Fang Han,
Donghua University (China); Jian Cui, Beijing University of
Aeronautics and Astronautics (China)
Leaf area index (LAI) is a crucial variable in agronomic andenvironmental studies, because of its importance for estimating
the amount of radiation intercepted by the canopy and the cropwater requirements. The LAI can be achieved by hemispheric
images which are obtained below the canopy with high accuracy
and effectiveness. But existing hemispheric images canopy-LAI
measurement technique is based on digital SLR camera with afish-eye lens. User needs to collect hemispheric image manually.
The SLR camera and fish-eye lens is not suit for long-term
canopy-LAI outdoor measurement too. In recent years, with thedevelopment of embed and image technology, low cost remote
canopy hemispheric image acquisition technology is becoming
possible.
In this paper, we present a remote hemispheric canopy image
acquisition system with in-field/host configuration. In-field node

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Conference 10025:
Advanced Sensor Systems and Applications VII
based on imbed platform, low cost image sensor and fish eyelens is designed to achieve hemispherical image of plant canopy
at distance with low cost. Solar radiation and T/H data are
obtained for invalid hemispherical image elimination and nodemaintenance too. Host computer interacts with in-field nodeby 3G network. The hemispherical image calibration and superresolution are used to improve image quality in host computer.
Result show that the remote canopy image collection system
can make low cost remote canopy image acquisition for LAI
effectively.

10025-59, Session Post

Concepts for compact mid-IR
spectroscopy in photochemistry
Phuong-Ha Cu-Nguyen, Hans Zappe, Univ. of Freiburg(Germany)
Mid-infrared (mid-IR) spectroscopy is among the mostwidely-applied tools for monitoring chemical reactions inphotochemistry. The unique and varied absorption spectraof precursors as well as reaction products serve as distinct“fingerprints” for the molecules in question, such that absorption
spectroscopy represents an essential means for analysis of a wide
range of photochemical reactions. Most of the relevant spectralfeatures are in the mid-IR range, at wavelengths ranging roughly
between 2 and 8 micrometers.
An academically-exciting and industrially-relevant developmentin photochemistry is the use of micro-reaction chambers: very
compact, millimeter-sized cavities with controlled flow conditions
in which reactants combine to yield the desired products,
typically under adverse pressure and temperature conditions.
There is an explicit need for on-line, in-situ but non-invasive
monitoring of the chemical constituents in the chamber, ameasurement for which mid-IR spectroscopy is again ideallysuited. However, classical mid-IR spectrometers, most popularly
Fourier Transform (FTIR) spectrometers are bulky, complex and
expensive, making them unsuitable as miniaturized monitoring
systems.
We present here new concepts for ultra-miniaturized mid-IR
spectroscopy using passive optical components which can bedirectly integrated with micro-reaction chambers thus enabling
spectrally as well as spatially-resolved monitoring of chemical
species. The spectrometer is based on micro-machined FabryPerot resonator filters realized using pairs of Bragg mirrors and a
precisely defined high-finesse resonant cavity, all fabricated using
silicon-based materials. A spatial variation of the cavity thickness
leads to discretized transmission spectra with high resolution.
The small size of the spectrometer, coupled with its realization
using highly-parallel microfabrication technologies, allows
realization of laterally-distributed spectrometers for spatiallyresolved measurements.
Design considerations and system simulation results will bepresented to demonstrate the flexibility and wide applicabilityof the approach. Spectroscopy performance for chemistrywith relevant absorption features around 3 micrometers will beoutlined and measurement results of transmission spectra in thismid-IR range will be considered.

10025-21, Session 5

Experimental and modeling study of offbeam quartz-enhanced photoacoustic
detection of nitrogen monoxide (NO)using a quantum cascade laser(Hong Kong, China)
This article presents the experimental and modeling study ofquartz-enhanced photoacoustic detection of nitrogen monoxide(NO) using the off-beam configuration and a distributedfeedback (DFB) quantum cascade laser (QCL) at 5.26 ?m as
excitation source. Trace gas monitoring of NO is one important
subject for both environmental protection and human healthmonitoring. Quartz-enhanced photoacoustic spectroscopy(QEPAS) with on-beam configuration is mostly adopted forgas detection. Compared to on-beam configuration, off-beamapproach has not only comparative detection sensitivity
but also significant advantage of simpler installation andoptical alignment. We systematically investigated the sensor
performance by measuring the signals corresponding todifferent horizontal and vertical distances between the centerof the micro-resonator (mR) and the QTF prongs. Pressure andhumidity are two important factors for gas photoacoustic signal
detection, especially, water vapor is usually a normal and criticalcomponent in gas samples such as human breathe. Hence, theeffect of both parameters on the NO concentration determination
were investigated. Theoretical simulations were also performed tointerpret the experimental results.

10025-22, Session 5

Amphiphilic block copolymer-based
photonic platform towards efficient
protein detection
Afroditi Petropoulou, National Hellenic Research
Foundation (Greece) and Univ. of Peloponnese (Greece);
Thomas J. Gibson, Efrosyni Themistou, Queen’s Univ.
Belfast (United Kingdom); Stergios Pispas, Christos
Riziotis, National Hellenic Research Foundation (Greece)
Use of novel functional materials can provide an efficient routeto the performance enhancement of sensing devices whencombined in appropriate platforms even by employing simple
interrogation schemes. Selective and low cost biosensors,
especially for protein detection can have a number ofapplications in different sectors. Here, the development of a low
complexity fiber optic based protein sensor by functionalizing
the surface of silica optical fibers using specially designed block
copolymer materials is presented. The copolymers utilized
are comprised of cationic blocks that can electrostaticallybind selected proteins and also appropriate functional groups
for reversible or non-reversible binding of protein molecules.
Non-reversible protein binding can lead to sensing elements
based on protein-analyte interactions. The coexistence of bothhydrophobic and hydrophilic blocks in the thiol-functionalized
PMMA117-b-P(DMAEMA17-TEMA2) and the vinyl-sulfonefunctionalized PMMA117-b-P(DMAEMA17-VSTEMA2) block
copolymers used in this work can provide the formation of
stable overlayers on fiber’s silica surface. At low pH PDMAEMA
is extensively protonated. Proteins having opposite charge
relative to the cationic PDMAEMA block can be absorbed by theoverlayer, changing its refractive index and enabling the sensing.
The PMMA117-b-P(DMAEMA17-TEMA2) has approximately
two –SH groups per chain that can react with the protein –SH groups giving a reversible binding. On the contrary thevinyl-sulfone functionalized polymer facilitates non-reversible
binding of proteins. The non-functionalized PMMA-b-PDMAEMA
copolymer was also tested for comparison. The developed
platforms have been evaluated for Bovine Serum Albumin (BSA)
sensing, a negatively charged protein at neutral pH, exhibiting
linear response to different BSA concentrations with very good
repeatability.

Chao Shi, Zhili Li, The Chinese Univ. of Hong Kong (HongKong, China); Wei Ren, The Chinese Univ. of Hong Kong

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185

Conference 10025:
Advanced Sensor Systems and Applications VII

10025-23, Session 5

PCF supports single mode.. Using the advanced technology like
capillary method and sol-gel method the proposed PCF may befabricated. The proposed PCF may use to detect colorful andtoxic gas.

Photo-acoustic spectroscopy gas
detection method based on multiple
reflection of optical path

10025-25, Session 5

Luo Han, Fengzhong Dong, Hua Xia, Hefei Institutes ofPhysical Science (China)
Gas absorption spectroscopy has been widely used inenvironmental monitoring, industrial production, medical
diagnosis, biological technology and monitoring of power
facilities. In a number of gas absorption spectrum technique,Photo-acoustic spectroscopy gas detection technology has theadvantages of high sensitivity, good selectivity, small size andreal time monitoring, has a widely used in the above fields. Photoacoustic spectroscopy based on photo-acoustic spectroscopy
is a Laser Absorption Spectroscopy Technique to converts
optical signals into sound signals. In this paper, a method toimprove the sensitivity of photo-acoustic spectroscopy system
is presented, which is combined with the technique of Herriotttype multiple pass cell. This novel technology was used todetect the CO2 concentration in ambient, selecting wavelength?=1608.7nm as a center wavelength of the laser light source ,anderecting two concave mirrors in the two ends of photo-acoustic
cell, which ensures two concave mirrors curvature radius andspacing to meet the conditions of stable resonator in order tomake the beams repeatedly through photo-acoustic cell. In thisexperimental apparatus, the design of the experimental device
can make the beam pass the cell 18 times. By comparing thesingle reflection and multiple reflection measurement results,
it is obvious that the signal is increased, and the feasibility ofthis method is verified. By this method, the sensitivity of Photoacoustic spectroscopy system was exactly improved without
increasing the source power, at the same time reducing thedetection limit. Therefore, the application of Photo-acoustic
spectroscopy technology will be used more and more widely,such as the detection of the isotope abundance, aerosol
concentration, the diagnosis of the gas concentration fromtransformer and so on.

10025-24, Session 5

Slotted-core photonic crystal fiber in gassensing application
Sayed Asaduzzaman, Kawsar Ahmed, Bikash Kumar
Paul, Mawlana Bhashani Science and Technology Univ.
(Bangladesh)
Combustible or harmful gasses noticeable all around are
adequate to decimating a geographical region of bringing abouta flame, explosion, and venomous exposure. This paper presentsa Slotted-core photonic crystal fiber gas sensor which shows highrelative sensitivity. The proposed PCF contains rectangular holes
in a slotted manner in the core region. The cladding contains
five rings of circular air holes arranged in a hexagonal shape.
The geometrical parameters like air hole diameters of cladding,cladding pitch, major and minor axis diameter of the rectangular
air holes and core pitch are varied to optimize the best outcomes.
Better guiding properties are shown by the proposed slottedcore PCF than the previous PCFs. Finite element method (FEM)with perfectly matched layer boundary (PML) circular boundary
condition is applied to investigate the guiding properties. The
proposed Slotted-core PCF shows the higher sensitivity of
48.26% and a low confinement loss of 1.26? 10 -5 dB/m at 1.33
?m wavelength of the absorption line of methane (CH4) andhydrogen fluoride (HF) gases. The whole numerical investigation
takes place in a wider range of wavelength from 1.3?m to 2.2?m. Other optical properties like Effective area, Beat length,
Splice loss are also analyzed and presented in this paper.
V-parameters are also examined which shows that the Proposed
186

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Small-molecule microarray-compatible
optical-biosensor-based high-throughput
screening
Chenggang Zhu, Yiyan Fei, Fudan Univ. (China)
We present a novel high-throughput screening platform basedon small-molecule microarrays (SMMs) and label-free obliqueincidence reflectivity difference (OI-RD) microscope. Firstly, wedeveloped OI-RD microscope which is a microarray compatiblelabel-free high-throughput detection method. OI-RD is the
special form of an ellipsometry measuring the phase changeof the reflected beam which is proportional to the surface
mass density of biomolecules on surface so that OI-RD enables
label-free detection of biomolecular interactions, getting rid ofproblems associated with labeling. Compatible with microarray,
OI-RD is able to monitor over 15,000 interactions in a single
experiment, providing a novel platform for high-throughput
screening. Secondly, we developed isocyanate chemistry to
prepared SMMs which is able to immobilize compounds with any
nucleophilic residue on phenyl-isocyanate functionalized glass
slides with high efficiencies. By printing 3,375 compounds onphenyl-isocyanate functionalized glass slides followed by 45?C
post-printing annealing of SMM, over 73% compounds can be
successfully immobilized on surface. Based on combination oflabel-free OI-RD microscope and as-prepared SMMs, we screenedsome non-labeled target proteins in high-throughput andlabel-free mode and we found hits for respective target protein.
The novel high-throughput screening platform enables target
proteins with unknown structure and/or unknown function tobe effectively screened. In addition, the advantages, low sample
consumption, high sensitivity, and multi-target screening, make ithave wide applications in high-throughput screening.

10025-26, Session 5

Person identification by using 3D
palmprint data
Xuefei Bai, Hebei Univ. of Technology (China); Shujun
Huang, Hebei University of Technology (China) andHebei University of Technology (China); Nan Gao, Hebei
University of Technology (China); Zonghua Zhang, Hebei
Univ. of Technology (China)
With the rapid development of network technology, information
security has attracted more and more attention. Palmprint
recognition is an emerging biometric recognition technology[1]. Compared with 2D (Two Dimension) palmprint, 3D (Three
Dimension) palmprint has several advantages of non-contact
measurement, one more dimension information and hard toforge, et al. However, most of the existing 3D palmprint matching
methods are designed for one-to-one verification and they are
not efficient to cope with the one-to-many identification case[2,3].
In order to acquire the 3D palmprint quickly, a capturing system
based on structure light and triangulation measurement isdeveloped. Using a DLP (Digital Light Processing) projector to
trigger a CCD camera to realize synchronization, 3D palmprint
data could be gathered within 1 second. With the purposeof rapid and real-time identifying 3D palmprint, a novel 3D
palmprint identification method based on Gabor filter andbinary code list is presented, and its applied algorithms such as

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Conference 10025:
Advanced Sensor Systems and Applications VIIfeature extraction and matching are investigated. Firstly, using
the curvature information of palmprint, ST (Surface Type) is
calculated. Then the orientation feature of each point which
could be binaryzation and listed in a table is further extracted byconvolving with Gabor filters. Finally, the test sample and training
samples are compared point by point and larger sums are chosen
as the discrimination criterion. Experimental results indicate thatthe proposed approach can identify a person within 240ms in
the case of 4000 samples. Compared with the traditional 3D
palmprint recognition methods, the proposed method has highaccuracy, speed and robustness, and is suitable for a large sample
database.
References
1. A. Kong, D. Zhang, M. Kamel. A survey of palmprint recognition.
Pattern Recognition. 2009, 42: 1408-1418.
2. Zhang D, Lu G M, Li W, et al. Palmprint recognition using
3-D information[J]. IEEE Transactions on Systems, Man, andCybernetics-Part C: Applications and Reviews, 2009, 39(5): 505519.
3. Hang D, Kanhangad V, Luo N, et al. Robust palmprint
verification using 2D and 3D features[J]. Pattern Recognition,
2010, 43(1): 358-368.

10025-27, Session 5

Micro-capillary-based self-referencing
surface plasmon resonance fiber-optic
biosensor
Shimeng Chen, Yun Liu, Lixia Li, Zigeng Liu, Wei Peng,
Dalian Univ. of Technology (China)
A novel self-referencing surface plasmon resonance (SPR) fiberoptic biosensor is demonstrated using the micro-capillary as thesensing element. The fiber-optic sensor is fabricated by splicing
a piece of capillary between multimode fibers (MMFs). MMFs
act as the lead-in and lead-out fibers while the micro-capillary
is used as the sensing element. The sensor employs SPR mode
as a measuring signal and localized surface plasmon resonance(LSPR) mode and Febry-Perot (FP) mode as the referencing
signals. The SPR mode is generated in the gold film coated on
the outer wall of the micro-capillary; instead, the LSPR mode
is generated on the gold nanoparticles (GNPs) immobilized on
the outer wall of the micro-capillary and the FP mode is excitedin the micro-capillary filled with the deionized water. Because
SPR effects, LSPR effects and FP interference can occur in thecapillary simultaneously, the spectrum of the sensor exhibits
SPR absorption, LSPR absorption and FP interference fringe.
LSPR mode is sensitive to refractive index (RI) and insensitive totemperature; instead, FP mode is sensitive to temperature andinsensitive to RI. Therefore, LSPR mode and FP mode can beused as the referencing signals to compensate the effects causedby the bulk RI and the temperature fluctuation, respectively.
Experimental results show that this approach we presented
can compensate bulk RI and temperature effect and develop
this sensor as a practicable high-sensitivity sensing device. The
simple and low-cost SPR biosensor can be used for sensing in thefield of biochemical.

Wang, Chinese Academy of Medical Sciences (China)
Breath acetone is a promising biomarker of diabetes mellitus inboth humans and animals. At present, using breath acetone as anoninvasive alternative for diabetes screening and management
is still a challenge. A fundamental question, the quantitative
relationship between breath acetone concentration andestablished clinical diagnostic parameters, remains unaddressed
because of limited clinical data and physiological processcomplexity. With an integrated standalone, on-site cavity
ringdown breath acetone analyzer, LaserBreath-001, we tested
breath samples from 42 type 1 diabetic (T1D) patients, 312 type2 diabetic (T2D) patients, 52 healthy subjects, and 126 T1D rats.
The relevant clinical information, such as simultaneous blood
glucose (BG) level, blood beta-hydroxybutyrate (BHB) level,glycohemoglobin (A1c), gender, age, body weight, and fasting
status, was also recorded.
In the cross-sectional studies, the obtained breath acetone
concentrations were higher in the diabetic human and rat
subjects compared with those in the control groups. A moderate
positive correlation between the mean individual breath acetone
concentrations and the mean individual BG levels was observedin the 20 T1D patients without ketoacidosis. No correlation
between individual breath acetone and individual simultaneous
BG was observed in the T1D, T2D, and healthy human, or the
rat subjects. In the longitudinal studies, the breath acetone
concentrations in a T1D patient with ketoacidosis decreased
significantly and remained stable within 5 days during the
hospitalization. Also, a 30-day continuous observation among
20 T1D outpatients and 5 healthy subjects demonstrated that
breath acetone measurement was a promising tool for diabetes
screening and management with a screening rate of 74% orhigher under specifically controlled condition. The breath
acetone influencing factors, such as age, gender, body massindex, A1c, and fasting status, were investigated individually andcomprehensively.

10025-29, Session 6

Optical properties of silicon microtube
doped with upconversion nanocrystals
Yundong Zhang, Hui Li, Harbin Institute of Technology(China); Hanyang Li, Harbin Engineering Univ. (China);
Chang Qiu Yu, Yong Feng Wu, Zinwaung Htwe, Harbin
Institute of Technology (China)
Nanocrystals of ?-NaLuF4 :Yb3+/ Ho3+with average diameter
about 400nm were integrated in silica-based microtube by asimple flame heating method. The fabricated microtube has adiameter range from 2 µm to 30 µm and lengths up to hundreds
microns. The fluorescence of upconversion nanocrystals (UCNCs)
can propagate along the single microtube. To prove the single
UCNCs doped MT can be used as an active waveguide wemeasured the guiding performance of it. Optical temperaturesensing based on the single UCNCs doped microtube was also
demonstrated, the sensitivity of UCNCs doped microtube issignificant sensitivity for temperature sensor applications in therange of 300-375K.

10025-28, Session 510025-30, Session 6

Application of LaserBreath-001 for breath
acetone measurement in subjects withdiabetes mellitus

Light propagation in strip and slot
waveguide arrays for sensing

Zhennan Wang, Chinese Academy of Medical Sciences(China); Meixiu Sun, Chinese Academy of Medical Sciences(China); Zhuying Chen, Xiaomeng Zhao, Yingxin Li, Chuji

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Qingyan Ma, Fan Qi, Yufei Wang, Wanhua Zheng, Instituteof Semiconductors (China)
Light propagations in strip and slot waveguide arrays forsensing are proposed and analyzed with a new theory ofquantum walk. The waveguide arrays are designed on silicon-on#PhotonicsAsia

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Conference 10025:
Advanced Sensor Systems and Applications VII
insulator and can be fabricated with mature and cost-efficientcomplementary metal-oxide semiconductor technology. A new
slot waveguide array modified by conventional strip waveguidearray with electric field mainly confined in the cladding region isinvestigated. Quantum walks have an exact mapping to classicalphenomena as verified by experiments using bright laser light, sothat they are introduced in our work as theoretical foundation.
The weakly coupled-mode theory is used to extract the coupling
coefficient of waveguide arrays, which is simulated by Finite
Element Method. By a series of analysis we take the width ofwaveguide of 450 nm and the coupling distance of 200 nm forstrip waveguide array. And for slot waveguide array we take thewaveguide width and coupling distance of 420 nm and 180 nm
respectively, with a 100nm slot in the center of waveguide. At
last the waveguide array covered by a thin layer of graphene
is investigated, which brings higher sensing property as well
as a much better biocompatibility. With the monochrome light
injection the intensity distribution at the end of the arrays
changes with the refractive index of the sensing area (cladding
region) and it can be explained by quantum walks theory. Whileboth arrays show excellent sensing characteristics, the designed
slot array can possess compact footprint and high refractive
index resolution, reaching 1E-11 RIU theoretically.

10025-31, Session 6

Multimode interference structures assensing elements integrated into MachZehnder interferometers in polymer foils
Yanfen Xiao, Alexa Langenecker, Meike Hofmann, Stanislav
Sherman, Hans Zappe, Univ. of Freiburg (Germany); Claas
Mueller, Uwe Gleissner, University of Freiburg (Germany)
Integrated Mach-Zehnder interferometers (MZIs) basedon flexible polymer materials have been demonstrated asevanescent field sensors for the detection of refractive indicesor molecule concentrations. Optical polymers, with their tunablerefractive indices and viscosities, enable cost-efficient roll-to-roll
manufacturing on flexible foils leading to cheap and disposable
sensors. Compared to rigid inorganic sensor systems, foilbased systems exhibit a lower sensitivity due to their material
properties, in particular available refractive indices and thermooptical instabilities. Additionally, the commonly used applicationof a measurement window becomes more difficult in a realroll-to-roll fabrication process. We have previously demonstrated
foil-based asymmetric MZIs with different widths in sensing andreference arm which do not need a measurement window. Thesesystems are perfectly compatible with roll-to-roll fabrication
but attain lower sensitivities than symmetric systems using ameasurement window.
We present here the use of a multimode interference structure(MMI) inserted into the sensing arm of the interferometer toincrease the sensitivity. We consider the expected interference
signal from numerical simulations and optimize the systemin terms of sensitivity, dimensions and absorption losses. The
designed MMI-MZI systems are fabricated by hot-embossing
the waveguides into a PMMA foil serving as substrate and lower
cladding. The core layer, consisting of a customized co-monomer,
is applied by spin-coating followed by polymerization, thereby
forming inverted rib waveguides with a total height of 3 µm andwidths between 2 and 3.5 µm. The selected MMI has a width of
7 µm and a length of around 10 mm. Finally, we apply water/glucose solutions in different fractions to demonstrate thefunctionality of the MMI-MZI system as refractive index sensor.

188

SPIE Photonics Asia·

10025-32, Session 6

Optimizing the loss of one-dimensional
photonic crystal towards high-sensitivity
Bloch-surface-wave sensors underintensity interrogation scheme
Weijing Kong, Tianjin Univ. of Technology and Education(China); Yuhang Wan, Kun Du, Beihang Univ. (China);
Wenhui Zhao, Tianjin Univ. of Technology and Education(China); Shuang Wang, Tianjin University of Technology
and Education (China); Zheng Zheng, BeiHang Univ.
(China)The reflected intensity change of the Bloch-surface-wave (BSW)
resonance influenced by the loss of a truncated one-dimensional
photonic crystal structure is numerically analyzed and studied
in order to enhance the sensitivity of the Bloch-surface-wavebased sensors. The finite truncated one-dimensional photonic
crystal structure is designed to be able to excite BSW mode
for water (n=1.33) as the external medium and for p-polarizedplane wave incident light. The intensity interrogation scheme
which can be operated on a typical Kretschmann prism-coupling
configuration by measuring the reflected intensity change of theresonance dip is investigated to optimize the sensitivity. A figureof merit (FOM) is introduced to measure the performance of the
one-dimensional photonic crystal multilayer structure under thescheme. The detection sensitivities are calculated under different
device parameters with a refractive index change corresponding
to different solutions of glycerol in de-ionized (DI)-water. The
results show that the intensity sensitivity curve varies similarly
with the FOM curve and the sensitivity of the Bloch-surfacewave sensor is greatly affected by the device loss, where an
optimized loss value can be got. For the low-loss BSW devices,
the intensity interrogation sensing sensitivity may drop sharply
from the optimal value. On the other hand, the performance ofthe detection scheme is less affected by the higher device loss.
This observation is in accordance with BSW experimental sensing
demonstrations as well. The results obtained could be useful for
improving the performance of the Bloch-surface-wave sensors forthe investigated sensing scheme.

10025-33, Session 6

Rapid wasted-free microfluidic fabrication
based on ink-jet approach for microfluidic
sensing applications
Ungkarn Jarujareet, Ratthasart Amarit, Sarun
Sumriddetchkajorn, National Electronics and Computer
Technology Ctr. (Thailand)
Realizing that current microfluidic chip fabrication techniques
are time consuming and labor intensive as well as always havematerial leftover after chip fabrication, this research work
proposes and demonstrates an innovative approach for rapid
microfluidic chip production. The key idea relies on a combinationof a widely-used inkjet printing method and a heat-based
polymer curing technique with an electronic-mechanical control,
thus eliminating the need of masking and molds compared totypical microfluidic fabrication processes. In addition, as theappropriate amount of polymer is utilized during printing, there
is no material wasted. Our inkjet-based printer can print out thedesired microfluidic chip pattern directly onto a heated glass
surface, where the printed polymer is suddenly cured. Our proofof-concept demonstrations for widely-used single-flow channel,
Y-junction, and T-junction microfluidic chips, which are utilized
in several microfluidic sensing applications, are described. The
whole microfluidic chip fabrication process of our demonstrationwww.spie.org/pa·

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Conference 10025:
Advanced Sensor Systems and Applications VII
reveals that it requires only 3 steps with a fabrication time of < 6
minutes.

10025-34, Session 6

Magneto-optic sensor based onelectrogyration compensation and singlequartz crystal

our research group has implemented a lot of highly sensitive
fiber acoustic sensing applications in terms of intensity, beatfrequency, phase, and so on.

10025-36, Session 7

Temperature sensor based on onedimensional photonic crystal with defectChangsheng Li, He Cui, BeiHang Univ. (China); Xuan
Zhang, Bright Crystal Technology, Inc. (China)

Kulandisamy Wilson, Arul Anandar College (India); Nambi
Ramanujam, K.L.N. College of Engineering (India)

Magnetooptic sensors have potential applications to themeasurement of magnetic field or current in many fields
including electric power system and scientific experiments. Mostof them are based on various magnetooptic effects in opticalcrystal or fiber, e. g. Faraday effect. To date, the most successful
optical current sensor is based on Sagnac interferometer andclosed-loop signal processing scheme. However, this closedloop sensing scheme is achieved by using an electrooptic
phase modulator which is separated from current sensing
fiber or crystal due to the need of electrical insulation, thus itis easily influenced by various external interferences. To solve
this problem, a magnetooptic sensor based on electrogyrationcompensation and single lead molybdate crystal has been
proposed recently (refer to IEEE Sensors J. 16(9), 2982-2987,
2016). However, the compensating voltage is as high as 16V/Gs
due to a small electrogyration coefficient of the crystal.

The temperature dependence of the defect mode in a one
dimensional photonic crystal (PC) are theoretically investigatedby transfer matrix method. The effect of temperature on eachlayers are carried out by considering the thermal expansion effectand thermo-optical effect. By simultaneously incorporating these
two effects, the PC structure is designed as (HL)NH(HL)N with
SiO2 (H) and air (L) layers. The sensitivity is determined by theshift in wavelength of the transmittance peak with temperatureand the average shift is 0.787 nm /K. It is also found that the
wavelength of the transmission peak is shifted towards the higher
wavelength region with increase of temperature.

In this paper, another magnetooptic sensor based onelectrogyration compensation is proposed and demonstrated
experimentally by using single quartz crystal. Compared withprevious magnetooptic sensor using lead molybdate crystal, thecompensating voltage is remarkably decreased to 0.8V/Gs for asingle crystal with a length of 23mm and 50Hz ac magnetic field
less than 267Gs. In addition, besides electrogyration and Faraday
effects, quartz crystal also exhibits electrooptic Pockels effectand natural optical activity which don’t exist in lead molybdate
crystal, thus the sensing principle is different from that of themagnetooptic sensor using lead molybdate crystal. The proposed
sensor can be used for the closed-loop measurement of strong
magnetic field.

10025-35, Session 7

High-sensitivity fiber optic acoustic sensor
technology (Invited Paper)
Ping Lu, Huazhong Univ. of Science and Technology(China)In recent years, our research group has proposed a series ofhigh-sensitivity fiber opticacoustic sensor(FOAS) technology
solutions. Such as a kind of differential intensity modulation
method based on non-standard fiber optic coupler, whose
intensity sensitivity can be 2.63 mW/Pa. This sensor has good
response in the range of 20Hz-20kHz; Including another novel
solution based on passively mode-locked multi-longitudinalmode fiber laser for sound pressure sensing, a highly acousticpressure sensitivity of 147.2Hz/Pa is achieved at the soundpressure range 0-20Pa; Besides,a MI based low-frequency
FOAS employing plastic diaphragmis alsoresearched, whose
sensitivity can be -118dB at 90-500 Hz. Furthermore, speciallyfor infrasound sensing, EFPI sensors based on composite film
or polymer film are also fabricated. And experimental results
show high sensitivity -138.3 dB re 1 V/µPa @1 Hz and infrasoundworking frequency 1-20Hz. In addition, a quasi-distributed fiber
optic acoustic sensing scheme based on optical vernier effectprinciple is also raised, the sensitivity is as high as 45.3rad/Pa,
and employing the WDM technology, quasi-distributed fiber
optic acoustic sensing application can be realized. In short,

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10025-37, Session 7

A novel quarter wave plate and its
applications to the reflective fiber-optic
current sensor
Ruibin Zhang, Beijing Univ. of Technology (China)
In this paper, a novel quarter wave plate which is composed oftwo segments high birefringence fibers which are orthogonallywelded is proposed and demonstrated. By tuning the uniform
strength beam onto which one of the two fibers is adhered, thelength of the fiber can be precisely controlled and so quarterwave plate can be got. The theory model of the reflective current
sensing system with the novel quarter wave plate is establishedusing Jones matrix method. The influences of the deviation of
welding angle and phase difference of the quarter wave plateon the sensing system is studied in detail, respectively. The
temperature stability of the quarter wave plate is studied indetail. Based on the characteristics of the high birefringencefiber (panda) under the temperature and axial strength change,a temperature compensation method is proposed. The method
is realized by adhere part of the high birefringence fiber tothe unique strength beam which is made of acrylic. Whentemperature changes, the effect on the beat length change
can be compensated by the effect of strength change whichis brought by thermal expansion. The quarter pate has theadvantages of high stability and easy for precisely controlling.

#PhotonicsAsia

189

Conference 10026: Real-time Photonic Measurements,
Data Management, and Processing II
Wednesday - Thursday 12–13 October 2016
Part of Proceedings of SPIE Vol. 10026 Real-time Photonic Measurements, Data Management, andProcessing IItime delay lines for analog radiofrequency processing require
to design each single core so that it features an independentgroup delay behavior. We present the design of trench-assisted
heterogeneous multicore fibers optimized in terms of higherorder dispersion, crosstalk and bend sensitivity designed tooperate as a broadband sampled delay line. This work opens theway towards the development of broadband fiber-distributed
microwave signal processing benefiting from the stability,
versatility and compactness brought by the proposed multicore
fiber approach.

10026-1, Session 1

Honeycomb lattice meshes forreconfigurable universal microwave
photonics processors (Invited Paper)
Jose Capmany, Ivana Gasulla, Daniel Perez, Univ.
Politécnica de Valencia (Spain)
General programmable processors are called to play key role in
the implementation of future general programmable integrated
processors, which will be required in massive scale application
scenarios such as 5G communications and the Internet of Things.
Bringing the promise of implementing several functionalities
by suitable programming of one common photonic hardware
architecture, these devices feature additional advantages in termsof low cost and enhanced reliability fabrication when combinedwith Generic Integration (GIM) and Generic Foundry (GFM)
Models. The central element of the proposed reconfigurable
optical processors is a versatile reconfigurable optical core,
where the main signal processing architectures can be set up
in response to different electronic control signals. The main
proposed configurations are based on cascade of finite andinfinite impulse response cells (MZIs and ORRs). A different
approach based on a 2D tuneable-coupler-based square meshnetwork inspired by the photonic FPGA-like concept employs
3-dB balanced Mach-Zehnder Interferometers (MZIs) as its basic
building block, enabling the synthesis of any kind of opticalcore circuit topology. In this paper we propose a honeycomb
mesh topology for the implementation of a specific class ofreconfigurable processor for Microwave Photonics (MWP)
applications. We and carry out an analysis that highlights its
superior metrics compared to the previously proposed squaremesh in terms of integration capabilities and photonic integrated
circuit (PIC)-synthesis performance. We illustrate its applicability
in implementing medium-complexity MWP processors. We
provide also an evolution roadmap for this device.

Distributed radiofrequency signal
processing using multicore fibers (Invited
Paper)

Next generation fiber-wireless communication paradigms
will require entirely new technologies to address the current
limitations to massive capacity and connectivity, enabling
multigigabit-per-second 5G wireless systems and the era ofInternet of Things. We envision the application of spatial divisionmultiplexing technologies to these upcoming fiber-wirelessnetworks as a firm candidate to increase the end user capacity
while providing adaptive radiofrequency-photonic interfaces.
This approach leads to the novel concept of “fiber-distributed
signal processing”, providing radio access distribution and
MIMO antenna connectivity while simultaneously implementing
broadband Microwave Photonics processing. In particular, we
capitalize on the spatial parallelism inherent to multicore fibers
to implement a broadband tunable true time delay line forradiofrequency signals, which is the basis of multiple processing
applications such as signal filtering, arbitrary waveformgeneration and squint-free radio beamsteering.
While keeping comparable propagation characteristics in all thefiber cores is important in digital communications, tunable true·

Antonella Bogoni, Consorzio Nazionale Interuniversitario
per le Telecomunicazioni (Italy); Sergio Pinna, Scuola
Superiore Sant’Anna (Italy)
Landslides and other ground failures are responsible for greatdamages. Radars have been exploited for controlling theseground movements, providing complete and precise deformation
maps of large areas.
Commercial radar relies on the Stepped-Frequency ContinuousWave (SFCW) technique with differential interferometry. It
exploits several coherent sinusoids to synthesize a large signal
bandwidth and to reduce the system noise for an improved
measure resolution.
Currently this technique is limited to the use of coherent
sinusoids in a single RF band, due to the issues in generating
multi-band coherent signals. Moreover, the lack of highly stabletunable RF oscillators leads to exploit only a fixed RF band.

Recently, the authors realized the first demonstrator ofa photonics-based coherent radar, with the possibility ofsimultaneously generating and detecting several RF signals,
in different RF bands guaranteeing an intrinsic high phasecoherence.

Ivana Gasulla, Sergi Garcia, Univ. Politécnica de Valencia(Spain)SPIE Photonics Asia

Photonics-based radar for coherent multiband differential phase estimation forenhanced displacement measurements(Invited Paper)

However, the capability to exploit coherent multi-bands would
further increase the synthesized signal bandwidth, and would
allow to tune the operative RF carriers for adapting the system tothe environment and to the observation range.

10026-2, Session 1

19010026-3, Session 1

This paper reports for the first time, the use of this photonicsbased radar for a SFCW technique and differential interferometry
based system. The intrinsic high phase coherence between theused bands avoids the use of correction algorithms. Moreover
the use of a single photonics-based transceiver for generating all
the RF carriers allows for a reduction of the whole system power
consumption and footprint.
An accuracy lower than < 200um over a range up to 3km has
been obtained.

10026-4, Session 1

Microwave photonic signal processing
based on distributed feedback
semiconductor optical amplifier (Invited
Paper)Ye Deng, Ming Li, NuanNuan Shi, Jian Tang, Shuqian Sun,www.spie.org/pa·

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Conference 10026: Real-time Photonic Measurements,
Data Management, and Processing II
Lihong Zhang, Ninghua Zhu, Institute of Semiconductors(China)Microwave photonic signal processing combines the advantagesof electronic technique (ubiquitous, flexible and high frequency
spectrum resolution) with the advantages of photonic technique(broad bandwidth, high speed, and low power consumption). It isconsidered as one solution to overcome the inherent limitationsof transmission speed and power consumption in conventional
electronic-based system. Over the last few years, an impressive
range of microwave photonic signal processors have been
proposed, but few of them come with reconfigurability, a feature
highly needed for practical signal processing applications.
In this paper, we propose and experimentally demonstrate
an analog optical signal processor based on a phase-shifted
distributed feedback semiconductor optical amplifier (DFBSOA). The proposed analog optical signal processor can bereconfigured to perform signal processing functions including
ordinary differential equation solving and temporal intensity
differentiation. The reconfigurability is achieved by controllingthe injection currents. In addition, The DFB-SOA can also be
used to realize a widely tunable microwave photonic filter (MPF)
with a single passband. Furthermore, our proposed DFB-SOA
based MPF also shows a potential application as an optical vector
network analyzer (OVNA). Finally, our demonstration provides asimple and effective solution for integrated microwave photonic
signal processing.

10026-5, Session 1

A broadband optically-steered phasedradar for target detection
NuanNuan Shi, Ye Deng, Lihong Zhang, Shuqian Sun,
Jian Tang, Ming Li, Wei Li, Ninghua Zhu, Institute of
Semiconductors (China)
A broadband X-band optically-steered phased array radar (PAA)
is proposed and applied to demonstrate the target detection
ability. In the proposed photonics-based PAA, high-dispersion
fiber is employed to realize the true-time delay (TTD) techniquewith the variable time delay between each adjacent channel from
-43.3 ps to 43.3 ps. Low amplitude ripple of ±0.5 dB and small
phase error of -0.13 ps/nm are realized by the power equalizationand the phase compensation. By tuning the optical wavelength
over C band, the beam steered angle in far field covers from -54
degree to 54 degree and the maximum error of the beam steered
angle is up to 7 degree with the frequency of 8.5 GHz~11.5 GHz.
Moreover, the beam patterns at 10 GHz are measured in the
wavelength of 1545 nm and 1538.5 nm and the error of which areless than 3 degree compared with the simulation results. As anapplication of the setup optically-steered phased array antenna
system, the detection ability of photonics-based radar is also
verified using X-band chirp signal. It is capable to rapidly detect
the target by simple tuning the optical wavelength. After thepulse compression of the received signal, the ranging resolutionis less than 2 cm. Therefore, it is able to realize the beam forming
steering with the broadband and the large scanning angle. We
believe that the demonstration can preferably promote thepracticality of optically-steered phased array radar.

10026-6, Session 2

Recent progress in on-chip linear andnonlinear microwave photonic signal
processing (Invited Paper)
Jian Wang, Huazhong Univ. of Science and Technology(China)Return to Contents

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We review our recent progress in on-chip linear and nonlinear
microwave photonic signal processing based on photonic
integrated devices on silicon platforms. By employing thedesigned and fabricated silicon microring resonators, silicon
photonic crystal nanocavities, and silicon Mach-Zehnder
modulator, we experimentally demonstrate diverse on-chip linear
and nonlinear microwave photonic signal processing: 1) bandstop
microwave photonic filter; 2) bandpass microwave photonic filter;3) optically-controlled tunable microwave photonic filter; 4) ultrahigh peak rejection notch microwave photonic filter; 5) photonicassisted microwave signal multiplication and modulation. The
operation performance of on-chip linear and nonlinear microwave
photonic signal processing is comprehensively evaluated in theexperiment.

10026-7, Session 2

High-accurate optical vector analysis
based on optical single-sideband
modulation (Invited Paper)
Min Xue, Shilong Pan, Nanjing University of Aeronautics
and Astronautics (China)
Most of the efforts devoted to the area of opticalcommunications were on the improvement of the optical spectral
efficiency. Varies innovative optical devices are thus developed
to finely manipulate the optical spectrum. Knowing the spectral
responses of these devices, including the magnitude, phase andpolarization responses, is of great importance for their fabrication
and application. To achieve high-resolution characterization,
optical vector analyzers (OVAs) based on optical single-sideband(OSSB) modulation have been proposed and developed.
Benefiting from the mature and high-resolution microwave
technologies, the OSSB-based OVA can potentially achieve aresolution of sub-Hz. However, the accuracy is restricted by
the measurement errors induced by the unwanted first-order
sideband and the high-order sidebands in the OSSB signal,
since electrical-to-optical conversion and optical-to-electricalconversion are essentially required to achieve high-resolution
frequency sweeping and extract the magnitude and phase
information in the electrical domain. Recently, great efforts havebeen devoted to improve the accuracy of the OSSB-based OVA.
In this paper, the influence of the unwanted-sideband induced
measurement errors and techniques for implementing highaccurate OSSB-based OVAs are discussed.

10026-8, Session 2

All-optical pulse compression forbroadband microwave signal based on
Brillouin scattering in optical fiber (Invited
Paper)
Weiwen Zou, Xin Long, Jianping Chen, Shanghai Jiao Tong
Univ. (China)
Pulse compression processing based on stimulated Brillouinscattering (SBS) in an optical fiber is theoretically andexperimentally demonstrated. Broadband microwave signal iselectro-optically modulated onto the pump lightwave that islaunched into one end of the fiber.
Acoustic wave in the fiber inherits the amplitude and phase
information of the pump lightwave and thus the coupling
between the acoustic wave and pump lightwave leads to theauto-correlated process of the pump lightwave as well as themodulated microwave signal. Derivation of the SBS coupling
equations shows that the short-pulse probe lightwave amplified
by the pump lightwave possesses the nature of auto-correlation#PhotonicsAsia

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Conference 10026: Real-time Photonic Measurements,
Data Management, and Processing II
formula. All-optical pulse compression of the broadband
microwave signal is implemented after a subtraction between thedetected probe pulse with and without SBS. A proof-of-concept
experiment with a linear frequency-modulated microwave signal(1 GHz sweep range) is carried out .

10026-10, Session 2

On-chip pulse shaper for optical andmicrowave arbitrary waveform generation
Shasha Liao, Xu Wang, Jianji Dong, Huazhong Univ. of
Science and Technology (China)

10026-9, Session 2

Ultrafast optical signal processing enabledby plasmonics (Invited Paper)
Maurizio Burla, Romain Bonjour, Felix Abrecht, W. Heni,
Claudia B. Hoessbacher, C. Haffner, Yannick Salamin, Yuriy
M. Fedoryshyn, Juerg Leuthold, ETH Zürich (Switzerland)
Plasmonic organic hybrid modulators recently demonstrated
ultra-low power consumption (a few fJ/bit) and ultrafast
operation (>100 Gbit/s) on ultra-compact footprints (100s µm2)
[1-8]. Novel ultrafast signal processing platforms on-a-chip may
be enabled by employing these unique characteristics. We will
first report recent progress on plasmonic modulation devices,and discuss how the same basic concepts can be applied toultrafast optical signal processing applications. Novel plasmonic
phase modulators (PPMs) [5], Mach-Zehnder [7] and IQmodulators [8] will be introduced. We will briefly discuss thestate of development of several applications based on thesedevices, ranging from optical interconnects [9] to ultrafast analog
signal processing of microwave and millimeter wave signals [10,11]. For these applications PPMs promise special benefits, thanks
to their theoretically unlimited RF bandwidth and compactness[1]. Finally, a perspective on the potential of using plasmonic
modulators for processing of ultrafast optical signals will begiven, e.g. in ultrafast optical phase shifters and delay lines [11],which can find applications e.g. in in-line processing techniques,on-chip arbitrary waveform generators [12], and more.
References[1] J. Leuthold et al.,“Plasmonic Communications: Light on a
Wire,” Opt. Photonics News, vol. 24, no. 5, pp. 28-35, 2013.
[2] A. Emboras et al., “Electrically Controlled Plasmonic Switches
and Modulators,” J. Sel. Topics Quantum Electron., vol. 21, no. 4,
pp. 276-283, 2015.
[3] W. Cai, J. S. White, and M. L. Brongersma, “Compact, HighSpeed and Power-Efficient Electrooptic Plasmonic Modulators,”
Nano Lett., vol. 9, no. 12, pp. 4403-4411, 2009.
[4] J. S. Schildkraut, “Long-range surface plasmon electrooptic
modulator,” Appl. Optics, vol. 27, no. 21, pp. 4587-4590, 1988.
[5] A. Melikyan et al., “High-speed plasmonic phase modulators,”Nat. Photon., vol. 8, no. 3, pp. 229-233, 2014.
[6] C. Haffner et al., “All-plasmonic Mach–Zehnder modulator
enabling optical high-speed communication at the microscale,”,Nat.Photon., vol. 9, no. 8, pp. 525, 2015.
[7] W. Heni et al., “108 Gbit/s plasmonic Mach-Zehnder modulator
with >70 GHz electrical bandwidth,” J. .Lightw. Technol., vol.34,
pp. 393-400, 2016.
[8] C. Haffner et al., “Plasmonic Organic Hybrid
Modulators&#x2014;Scaling Highest Speed Photonics to theMicroscale,” Proc. IEEE, vol. PP, no. 99, pp. 1-18, 2016.
[9] C. Hoessbacher et al., “Optical Interconnect with Densely
Integrated Plasmonic Modulator and Germanium Photodetector
Arrays,” OSA Technical Digest (online). p. Th1F.6.
[10] Y. Salamin et al., “Direct Conversion of Free Space Millimeter
Waves to Optical Domain by Plasmonic Modulator Antenna,”
Nano Lett., vol. 15, no. 12, pp. 8342-8346, 2015/12/09, 2015.
[11] R. Bonjour et al., “Ultra-Fast Millimeter Wave Beam Steering,”
J. Quantum Electron.vol. 52, no. 1, pp. 1-8, 2016.

Arbitrary waveform generation attracts a lot of interests in recent
years because of its widely applications in many different fields.
We have proposed and experimentally demonstrate two onchip pulse shaper schemes for microwave and optical arbitrary
waveform generation. These schemes are all fabricated on thesilicon-on-insulator (SOI) chips for its compactness and capability
to integrate with electronics. The two schemes based on finite
impulse response (FIR). By thermally controlling the amplitude
and phase of each path, we can obtain different applicationsof arbitrary waveform generation. The pulse shaper of opticalarbitrary waveform generation can be a programmable filter withcentral wavelength tunable, bandwidth tunable and passband
shape variable functions, and a high-order differentiator which
may obtain the first-order, second-order and third-orderdifferentiations likewise. It can also implement several typical
optical waveforms, such as the square waveform, triangular
waveform, sawtooth waveform and Gaussian waveform. The
pulse shaper for microwave arbitrary waveform generation canobtain several microwave waveforms with the central frequency
at 125GHz. Comparing with the proposed schemes by frequency
shaping and frequency-to-time mapping, our schemes do not
require any spectral dispersers or large dispersion mediums. And
all units in our schemes are broad-band devices, so there is no
bandwidth limitation in our schemes.

10026-11, Session 2

Optical true time delay based oncontradirectional couplers with single
sidewall-modulated Bragg gratings
Xu Wang, Jianji Dong, Shasha Liao, Huazhong Univ. of
Science and Technology (China)
We propose and demonstrate optical true time delay using
tapered SOI contradirectional couplers with single sidewallmodulated Bragg gratings. The contradirectional couplers consistof two tapered rib waveguides with different width, and the
Bragg gratings is modulated in the inner sidewall of the wider
one. The optical signal is launched from the wider waveguide andcoupled to the narrow waveguide through the Bragg gratings
structure. In the direction of light propagation, the waveguide
width varies linearly, so the reflection wavelength is different
at different position. Therefore, linear delay line can be realized
in the reflectance spectrum using the present structure. In thesimulation, grating period is 310nm and grating number is 2400,
so the grating length is 744?m. Using 2.5D FDTD simulation, thecurrent structure can realize optical group delay of 20ps withinbandwidth of 20nm. The proposed device is fabricated on a
220nm SOI chip with Electron Beam Lithography (EBL) andInductively Coupled Plasma (ICP) etching. In the experiment,
continuous light is modulated by 10GHz radio-frequency signal
through the optical intensity modulator and travel through thechip, which is finally detected by the oscilloscope. By adjusting
the wavelength of input light, group delay of different wavelength
are recorded by the oscilloscope. The experimental results showthat group delay of 20ps is realized in the bandwidth of 12nm. In
the end, the drift of the reflection spectrum and delay lines under
different temperature is analyzed. The reflection spectrum drifts
0.1nm/°C and causes redshift of the corresponding delay line.

[12] J. Wang et al., “Reconfigurable radio-frequency arbitrary
waveforms synthesized in a silicon photonic chip,” Nat. Commun.,vol. 6, 2015.

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Conference 10026: Real-time Photonic Measurements,
Data Management, and Processing II

10026-12, Session 3

Tunable optical frequency combs
generation in a CMOS-compatible high-Q
micro-ring resonator (Invited Paper)
Wenfu Zhang, Weiqiang Wang, Leiran Wang, Guoxi
Wang, Wei Zhao, Xi’an Institute of Optics and Precision
Mechanics (China)
We demonstrate a dual-pump approach, which allows the comb
spacing tuning freely, to generate tunable and robust opticalfrequency comb (OFC) in a high–Q CMOS-compatible microring resonator (MRR) in this paper. In our approach, the dualpump is generated by self-locked oscillation technique which
is immune to the thermal or mechanical perturbations, and theself-termination is effectively avoided for its intrinsic feedback
mechanism. The two pumps can lase stably and be tuned flexibly
by programming the tunable filter embedded in the laser cavity
loop, as the mode competition in the erbium-doped-fiber laser
is suppressed effectively by nonlinear interaction in the MRR.
By tuning the pump wavelength, broadband OFC with the
bandwidth of >200 nm and the frequency-spacing tunability
from 6- to 46-fold free-spectral-ranges (FSRs) is realized at a low
pump power. This approach could find potential and practicalapplications in many areas, such as optical metrology, opticalcommunication, and signal processing systems, for its excellent
flexibility and robustness.

10026-13, Session 3

Photonic-assisted compressive samplingsystems (Invited Paper)
Qiang Guo, Hongwei Chen, Minghua Chen, Sigang Yang,
Shizhong Xie, Tsinghua Univ. (China)
Compressive sampling (CS) has attracted considerable attention
as a novel data sampling technique and widely applied in diverse
fields including wideband spectrum sensing and biomedical
imaging in recent years. Compared with traditional electric CS
systems, photonic-assisted CS technique can overcome thebandwidth limitation of electronic devices. Meanwhile, it cansignificantly reduce the sampling rate of the back-end analog-todigital converter (ADC), easing the burden of data acquisition,transmission and storage. A photonic-assisted four-channel
wideband CS system based on wavelength division multiplexing
is proposed for the first time and multi-tone signals in the 5-GHz
frequency range are reconstructed faithfully with only a 120-MHz
ADC. Moreover, a CS platform for radar pulse signal acquisitionis built and numerous radar pulses in the 0.5-5 GHz range arespectrally sensed with a 500-MHz ADC. In imaging applications,
one-dimensional and 2-dimensional high-speed time-stretchbased single-pixel imaging systems are implemented with highframe rates three orders of magnitude faster than conventional
single-pixel cameras. To show the utility of our scheme inbiomedical applications, an imaging flow cytometer with athroughput of 100,000 cells/s is demonstrated, which has
settled the big data problem caused by high-throughput image
acquisition. In general, photonic-assisted CS systems show great
potential in both wideband spectrum sensing and biomedical
imaging applications.

10026-14, Session 3

Microwave frequency measurement basedon photonic sampling analog-to-digitalconversion
Yangxue Ma, Zhiyao Zhang, Di Peng, Jinfang Zou, Yong

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Liu, Univ. of Electronic Science and Technology of China(China)Broadband microwave frequency measurement is criticalimportant for extensively applications, including wirelesscommunications, radar systems and electronic warfare. The
electronic techniques of microwave frequency measurement areusually susceptible to electromagnetic interference (EMI) andthe bandwidth is limited by electronic bottleneck. Fortunately,
various photonic techniques for frequency measurement
which have large bandwidth and immunity of EMI have been
investigated, such as frequency-power mapping technique,frequency-time mapping technique and channelizing technique.
However, it is a contradiction in obtaining a large bandwidth anda high resolution simultaneously.
In this paper, a novel approach to implement microwave
frequency measurement based on photonic analog-to-digitalconverters (ADCs) is proposed. Specifically, three low repetition
frequency mode-locked lasers (MLLs) with co-prime repetition
frequencies are used to generate three ultra-short opticalpulse trains. The unknown microwave signal is down-converted
sampled by the three optical pulse trains through Mach-Zender
Modulators respectively. The modulated optical pulse trains aretranslated to electronic pulse trains by photodetectors (PDs),
and then converted into digital signals by the corresponding
electronic ADCs. The Fourier frequencies are gained by the
Discrete Fourier transform (DFT) and the final result of thefrequency measurment is obtained by calculating the three
Fourier frequencies based on frequency reconstructing algorithm.
The simulation results indicate that a large measurement rangeof 0-50GHz and an accuracy of ±4MHz are achieved. Therefore,both high resolution and large bandwidth are acquired byutilizing the proposed scheme.

10026-15, Session 3

Dual-frequency comb metrology with one
fiber laser
Xin Zhao, BeiHang Univ. (China); Yasui Takeshi, The Univ.
of Tokushima (Japan) and JST (Japan); Zheng Zheng,
BeiHang Univ. (China) and Collaborative Innovation Ctr. of
Geospatial Technology (China)
Optical metrology techniques based on dual optical frequency
combs have emerged as a hotly studied area targeting a wide
range of applications from optical spectroscopy to microwave
and terahertz frequency measurement. Generating two setsof high-quality comb lines with slightly different comb-toothspacings with high mutual coherence and stability is the key tomost of the dual-comb schemes. The complexity and costs ofsuch laser sources and the associated control systems to lockthe two frequency combs hinder the wider adoption of suchtechniques.
Here we demonstrate a very simple and rather different approachto tackle such a challenge. By employing novel laser cavity
designs in a mode-locked fiber laser, a simple fiber laser setup
could emit dual-comb pulse output with good coherence andhigh stability between the pulse trains. Based on such lasers,
comb-tooth-resolved dual-comb optical spectroscopy isdemonstrated. Picometer spectral resolving capability could be
realized with a fiber-optic setup and a low-cost data acquisition
system and standard algorithms. When applied to the terahertz
region, high accuracy measurement of CW terahertz wave isrealized based on dual terahertz comb, excited by one fiber dualcomb laser. Similarly, the frequency of microwave signals over alarge range can be determined based on a simple setup.
Our results unequivocally show the capability of such singlefiber-laser-based dual-comb scheme to realize different dualcomb applications with excellent quality for many real-world
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Conference 10026: Real-time Photonic Measurements,
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comb system could result in a significant change in the paradigmof dual-comb-based metrology technologies.

10026-16, Session 4

Secure key distribution applications ofchaotic lasers (Invited Paper)
Ning Jiang, Chenpeng Xue, Kun Qiu, Univ. of Electronic
Science and Technology of China (China)
Secure key distribution is the most crucial issue for acryptosystem. There are two types of secure key distribution
schemes that are based on the computational principles
and physical principles, respectively. In this talk we discuss
the physical-principle-based secure key distribution systems
adopting chaotic lasers. Differing from the conventional key
distribution systems where the key generation is based on adeterministic algorithm, the key generation is based on thephysical random generation which is not deterministic. The
security only depends on the probability that the eavesdropper
guess the precise physical operations which is usually controlled
by random parameters, and then the security of key can begreatly improved. We will introduce the theoretical model andprinciples of the secure key distribution based on chaotic lasers,
and demonstrate its performance and analyze the challenges forpractical implementation.

10026-37, Session Post

An instrument for on-line chemical oxygen
demand and nitrate in-water monitoring
Weiwei Feng, Dan Li, Zongqi Cai, Yongchun Zhang, Xiao
Xu, Yantai Institute of Coastal Zone Research (China)

10026-17, Session 4

Spatial mode analyzer based on rotational
Doppler effect (Invited Paper)
Jianji Dong, Huazhong Univ. of Science and Technology(China)The function to measure the mode distribution of orbital
angular momentum (OAM) light is essential to characterize OAM
performance. Although there are lots of works to measure OAM
modes, it is difficult to measure the power distribution of OAM
modes quantitatively and instantaneously, let alone measure thephase distribution. In this work, we demonstrate an OAM complex
spectrum analyzer, which enables to measure the power andphase distribution of OAM modes simultaneously by employing
rotational Doppler Effect. The original OAM mode distribution
is mapped to electrical spectrum of beating signals with aphotodetector. The power distribution and phase distributionof OAM superimposed beams are successfully obtainedby analyzing the electrical spectrum. We also extend themeasurement to other spatial modes, such as linear polarization
modes. These results represent a new landmark of spatial mode
analysis and show great potentials in optical communication andoptics quantum tomography.

10026-18, Session 4

Coherence loss: The emergence of opticalpolarization rogue waves (Invited Paper)
Lei Gao, Tao Zhu, Chongqing Univ. (China); Stefan
Wabnitz, Univ. degli Studi di Brescia (Italy); Yu Jia Li, Cong
Gao, Min Liu, Wei Huang, Chongqing Univ. (China)
We demonstrate a new kind of optical rogue waves, polarization
rogue waves (PRW) that appear with greatly deviated andunpredictable positions of states of polarization (SOPs), in
forming partially mode-locked fiber laser based on parametricfrequency conversion, where laser redistributes its energy from
center to sidebands through parametric instability (PI), and194

subsequently longitudinal modes are populated via cascaded
four-wave-mixing (FWM). The coherence of the PI gain lobes isinvestigated based on statistical analysis of single-shot spectra
obtained from disperse Fourier transformation. We find that thePI, which exhibits great fluctuations when it is spontaneously
grown from noise in conservative systems, possess a high degreeof coherence in dissipative laser system with gain. Adjusting
the intracavity polarization state controls the process of lossof coherence. During this process, the SOPs of frequencies
generated by cascaded FWM shows a tendency from fixed state
to bifurcation, and finally to randomization. Experiments revealthat the polarization deviation from the mean positions is due
to chaotic competition of cascaded FWM processes, including
both scalar and vector FWMs, through which the energy oflongitudinal modes with a SOP along the cross is transferred
into newly-generated SOPs. Different from the physical origin ofbreather for temporal or spectral rogue waves, the emergence of
PRW is attributed to the appearance of various types of multiple
photons mixing, where molecular-scale accuracy of dispersion
in commercial single mode fiber together with nonlinear phase
response of graphene leads to abrupt variation of phasematching condition.

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Chemical Oxygen Demand (COD) and Nitrate concentration
data are of vital importance in coastal water quality monitoring.
The traditional method for monitoring these two parameters
is a chemical method that consumes chemical reagent. The
drawbacks of these chemical methods are the waste theygenerate, and the difficulty in implementing in-situ long termmonitoring. A new instrument based on an optical method tomeasure Chemical Oxygen Demand and Nitrate concentration
without reagent is described in this paper. According to thedifferent water quality, optical path length of flow cell is variablein this system. A 10mm path length is selected in this paper.
And a Y type of structure of quartz optical fibers is used forreal-time compensation. Concentration calculation principle isbased on the analysis of absorption spectrum and partial leastsquare method. Comparison between model calculation andexperimental data is also discussed in detail with several test
samples. The implementation of standard test and measurements
for the collected water samples is presented in this paper.

10026-38, Session Post

An improved calculation model of weight
coefficient for three-dimensional flame
chemiluminescence tomography based onlens imaging theory
Ying Jin, Yang Song, Wenchao Wang, Xiangju Qu,
Zhenhua Li, Yunjing Ji, Anzhi He, Nanjing Univ. of Scienceand Technology (China)
Flame tomography of chemiluminescence is a necessary
combustion diagnostic technique that provides instantaneous
3D information on flame structure and excited species
concentrations. However, in most research, the simplification of
calculation model of weight coefficient based on lens imaging
theory always causes information missing, which influences
the result of further reconstructions. In this work, an improved
calculation model is presented to determine the weight
coefficient by the intersection areas of the blurry circle with thewww.spie.org/pa·

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Conference 10026: Real-time Photonic Measurements,
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square pixels, which is more appropriate to the practical imaging
process. The numerical simulation quantitatively evaluates theperformance of the improved calculation method. Furthermore,
a flame chemiluminescence tomography system consistingof 12 cameras was established to reconstruct 3D structure of
instantaneous non-axisymmetric propane flame. Both numericalsimulating estimations and experiments illustrate the feasibility of
the improved calculation model in combustion diagnostic.

10026-39, Session Post

Study on glucose photoacoustic signals
denoising based on a modified wavelet
shift-invariance thresholding method
Zhong Ren, Jiangxi Science and Technology Normal Univ.
(China) and Nanchang Univ. (China); Guodong Liu, Jiangxi
Science and Technology Normal Univ. (China)
During the monitoring of blood glucose concentration by using
photoacoustic technique, the photoacoustic signals of blood
glucose are easily contamined by noises. The denoising is anecessary work because the polluted photoacoustic signals
will seriously impact the prediction precision of glucose
concentration. To improve the denoising effect of the glucose
photoacoustic signals, a modified wavelet thresholding combined
shift-invariance algorithm was used in this paper. Meanwhile,an improved wavelet threshold function was proposed. The
improved wavelet threshold function can be regarded as thecompromise between the Donoho’s hard-threshold function andsoft-threshold function because it not only can overcome thepseudo-oscillation, but also can reduce the deviation between
the denoised signals and the original signals. In addition, theshift-invariance method was added into the improved algorithm,
which will greatly improve the denoising effect. To verify thefeasibility of the modified wavelet shift-invariance thresholddenoising algorithm, the simulation experiments were performedby using the software MATLAB. In experiments, the standard
test signal contained by Gaussian noise was denoised byseveral different wavelet denoising methods. Results show thatthe denoising effect of the modified wavelet shift-invariancethresholding algorithm is better than that of others because its
signal-to-noise ratio is largest and the root-mean-square error
is lest. Finally, the modified wavelet shift-invariance thresholddenoising was used to remove the noises of the photoacoustic
signals of glucose aqueous solutions. The good denoising effectwas obtained. Therefore, the modified wavelet shift-invariancethreshold denoising algorithm has a potential value in thedenoising of the glucose photoacoustic signals.

The process of second-order DP, comparing with DP’s process
which has one more cycle, makes its calculation amount atleast nine times of the DP’s. In order for real-time processing of
this complex algorithm, we propose a parallel structure for thesecond-order DP.
The searching process of the second-order DP is a loop structurewith three layers: the first layer corresponds to the pixels of thecurrent frame, the second and the third layer corresponds tothe pixels in the first and the second search region respectively.
So the problem of the parallelization of the second-order DPamounts to the problem of the parallelization of the multi-layer
nested loop. We utilize the loop parallelization method to design
and realize the parallelization of the second-order DP, which
reduces the process time greatly. The parallel algorithm has
been used on FPGA successfully. According to the experimental
result, the time consumption of the second-order DP can besignificantly reduced to the level of that of the traditional DP
algorithm.

10026-41, Session Post

Spatial sparse scanned imaging based oncompressed sensing
Qiaoyue Zhang, Yuntao He, BeiHang Univ. (China);
Yuedong Zhang, Beijing Institute Of Space Mechanics andElectricity (China)
A new passive millimeter-wave(PMMW) image acquisition andreconstruction method is proposed based on compressedsensing(CS) and spatial sparse scanned imaging. In this method,
the images are sparse sampled through a variety of spatial sparse
scanned trajectories, and are reconstructed by using conjugate
gradient-total variation recovery algorithm. The principles andapplications of CS theories are described, and the influence ofthe randomness of the measurement matrix on the quality ofreconstruction images is studied. Based on the above work, thequalities of the reconstructed images which were obtained by
the sparse sampling method were analyzed and compared. The
research results show that the proposed method can effectively
reduce the image scanned acquisition time and can obtain
relatively satisfied reconstructed imaging quality.

10026-42, Session Post

Design of non-contact optic measurement
system for lunar sample sealing device
Chunyong Wang, Lanzhou Institute of Physics (China)

10026-40, Session Post

A real-time implementation method of
second-order DP algorithm based on
FPGA
Chenggang Sun, Shuo Wang, Yiqun Zhang, China
Aerospace Science & Industry Corp. (China)
The Dynamic Programming (DP) algorithm is an effective
algorithm for target detection?but its detection performancefor moving target is low. The faster the speed of target is, thelower detection performance is. In order to solve this problem,
we have proposed an improved algorithm (denoted as secondorder DP). A second-order random walk model is assumed in thesecond-order DP for the target state innovations, which improves
the DP’s target searching accuracy and detection performance.
As the second-order model is adopted, the searching processof second-order DP is extended to two steps compared with
DP’s one step, which highly increases its calculation amount.

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According to the thermal control coatings and of lunar sample
sealing device and the requirement of lunar sample sealing device
parameters measurement , Non-contact image measurement
system is designed and calibrated using Contact measurement
system. some relevant experimentation is carried out. Experimentresult shows that:the data measeured using Non-contact image
measurement system is consistent with contact measurement
system ,and Non-contact image measurement can be used tomeasure characteristic parameters of lunar sample sealing device.

10026-43, Session Post

Short pulse acquisition by low sampling
rate with phase-coded sequence in lidar
systemLong Wu, Qingheng Zhang, Wentao Lv, Xiaocheng Yang,
Jiajia Xu, Jindi Yan, Zhejiang Sci-Tech Univ. (China); Yong

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Conference 10026: Real-time Photonic Measurements,
Data Management, and Processing II
Zhang, Harbin Institute of Technology (China)
Normally lidar systems require the collection and determinationof every returned laser pulse for the judgement of object,which works for low frame rate lidar system due to the limited
response speed of detectors. It is not practical for imaging
lidar system with high resolution, which demands high frame
rate as high resolution needs short laser pulses, especially forphase coded lidar systems. This paper proposes a phase coded
sequence acquisition method for signal preprocessing throughdetector. The system employs an m-sequence with N bits fordemonstration. The laser pulses are modulated into a phase
coded sequences and illuminate targets while the detector iscontrolled to accumulate N+1 bits of the echo signals with thecorrelation calculation revealing the time delay of the echo
signals. An indoor experiment achieved 2 us resolution with thesampling period of 28 us by employing a 15-bit m-sequence. Thismethod achieves the acquisition of m-sequence with narrow
subpulse width whereas the sampling frequency is kept low. This
paper also presents the phase coded imaging lidar simulation,
which achieved 1.5m range resolution with a 50 kHz sampling
frequency by employing a 2047-bit m-sequence. The simulationshows a potential method to improve the detection capabilities
of narrow laser pulses with the detectors at a low frame rate,
especially for the imaging lidar systems. Meanwhile, the lidar
system is able to improve the range resolution with available
detectors of restricted performance.

10026-44, Session Post

interferometric measurement. It has advantages of wide-range,high-accuracy and fast speed at the rate about 10000 pts/s.
Such a distance measurement system needs dedicated higher
performance of the data acquisition and processing hardware
platform to support. This paper introduces the dedicatedplatform of the developed absolute distance measurement
system.
This platform is divided into three parts according to theirrespective functions. First part is the data acquisition module,
which function is mainly to realize the A/D conversion. In thispart we designed a sampling clock adjustment module to assist
the A/D conversion module to sample accurately. The samplingclock adjustment module accept a 250MHz maximum reference
clock input, which from the same femtosecond laser source as
the optical measurement system, then generate an output clock
for the A/D converter that can be delayed up to 20ns with aresolution of 714ps. This data acquisition module can convert theanalog laser pulse signal to digital signal with a 14 bits resolution
and a 250 MSPS maximum sample rate. Second is the dataprocessing and storage module consists of FPGA and DDR3
modules. The FPGA module calculates the test distance by the
16 bits digital sampling signal from the front data acquisition
module. The DDR3 module implements sampling data caching.
Finally part is the data transmission and peripheral interfaces
module based on three DB9 and USB2.0. We can easily debug
the platform in the PC and implement communication with uppermachine. We tested our system used dedicate test bench inreal-time. The scope of the measurement system range is 0 to 3
meters and the measurement deviation is less than 10um.

Measuring the relaxation time of thexenon atoms and the rubidium atoms

10026-46, Session Post

Peng Jiang, Zhiguo Wang, Yingying Li, Qiyuan Jiang, Hui
Luo, National Univ. of Defense Technology (China)

Shihan Tang, Zhenxing Wu, Fei Xu, Nanjing Univ. (China)

In the nuclear magnetic resonance gyroscope, the detection ofpolarization of nuclear spins and motion information is usuallyachieved by the atomic spin of alkali atoms and noble gas. But
the spin parameters of the work atoms are mainly evaluatedby the relaxation time. Relaxation time is so important that can
influence signal to noise ratio, dynamic range, start time andother parameters of the gyroscope. So its accurate measurement
is an important problem in the study of nuclear magnetic
resonance gyroscope performance. Here we are given a variety
of measurement methods of the transverse relaxation time andthe longitudinal relaxation time. First of all, we are given theindustry standard methods for measuring spin lifetimes- the Free
Induction Decay Method. Then we are also given the improved
free induction decay method, the ratio method and the Magnetic
resonance broadening fitting method to measure the transverse
relaxation time. We are given the flipped polarization method inmeasuring the longitudinal relaxation time. At the same time bychanging the experimental conditions, we get the longitudinalrelaxation time with the flipped polarization method under avariety of conditions. Finally, comparing the several methods ofmeasurement, and we can get the best methods of measurement
in different conditions.

10026-45, Session Post

Data acquisition and processing platformin the real-time distance measurement
system with dual-comb lasers
Kai Ni, Lanlan Wang, Qian Zhou, Xinghui Li, Hao Dong,
Xiaohao Wang, Graduate School at Shenzhen, Tsinghua
Univ. (China)

Tunable microfiber nonlinear effects
Nano/micro-fibers (NMFs) have unique optical characteristics
such as strong confinement of light, which can contribute to
the high nonlinearity and be applied in frequency conversion
including surface second-harmonic generation and four-wave
mixing. Phase matching is a critical issue and depends on thefiber size and dispersion. It is difficult to tune the diameter ofa fabricated NMF, however, it is we can much more easily tochange the dispersion by controlling the ambient refractive index.
A number of common pure and mixed liquids, such as water,
methanol, ethanol can be used to shift the dispersion of the NMF
and achieve phase-matching condition.
For surface second harmonic generation at the wavelength of1064 nm phase matching diameter of the air-cladding NMF, is 525
nm. The water- and ethanol- cladding NMF increase the diameterto 767 nm and 832 nm separately. Then we can realize thecontinuous shift of the dispersion and achieve phase matchingcondition by controlling the liquid concentration if the diameterof a NMF is in the range of 767 nm – 832 nm, which means that
we don’t need fabricate a NMF with an accurate diameter.
For degenerate four-wave mixing, the phase matching antiStokes and Stokes have the same frequency shift from pumpwavelength. Here we investigate two liquid claddings: water andmethanol, which have the similar refractive index at 1064 nm. The
effective phase mismatch of degenerate four-wave mixing canbe expressed as ? =?k+2?P, where ?k is the phase mismatch, ? isthe nonlinear coefficient, and P is the pump power. The ? changes
with different cladding material and different anti-Stokes (Stokes)
frequency shift. When the pump wavelength is 1064 nm, the peak
power is 2.2 kW and the diameter of 1.7 ?m, the phase matchinganti-Stokes (Stokes) wavelengths of a water-cladding and amethanol-cladding NMF, is 689 nm (2334 nm) and 657nm (2792nm), respectively. It shows that we can get tunable visible andinfrared sources by mixing water and methanol.

The real-time distance measurement system with dual
femtosecond comb lasers combines time-of–flight and196

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Conference 10026: Real-time Photonic Measurements,
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10026-47, Session Post

10026-49, Session Post

Comparison of correlation algorithms withcorrelating Shack-Hartmann wave-front
images

A novel scattered pilot-aided channel
compensation for CO-OFDM systems

Hangcheng Zhou, Lanqiang Zhang, Lei Zhu, Hua Bao,
Youming Guo, Xuejun Rao, Libo Zhong, Changhui Rao,
Institute of Optics and Electronics (China)
Correlating Shack-Hartmann wavefront sensor is widely used insolar adaptive optics in which the relative shift between different
subapertures by correlation algorithm is computed, and then thecontrol voltage by wavefront reconstruction can be estimatedto use for correcting the wavefront distortion induced byatmospheric turbulence. In this paper, several different correlation
algorithms including Cross-Correlation Coefficient, Absolute
Difference Function, Absolute Difference Function-Squared, andSquare Difference Function are used to estimate relative shift incorrelating Shack-Hartmann wavefront sensor with the different
observed solar structure such as sunspot, solar pore and solar
granulation. The measurement noise RMS error is computed tocompare the performance of the correlation algorithms. The
results show the correlation algorithm precision is directly related
to the solar structure. The measurement noise is relatively small
with the relatively high contrast target, and vice versa. At thesame time, the size of reference image also could influence themeasurement noise, the larger size of the reference image, thesmaller the measurement noise is.

10026-48, Session Post

Impacts of PM concentrations on visibility
impairment
Guo Jie, Hangzhou Zetian Technology Co. Ltd. (China); Yu
ZhiWei, Hangzhou Zetian Technology Co., Ltd. (China)
Visibility, as a standard of human visual perception of theenvironment, and has directly associated with air quality andatmospheric climate. Recently, atmospheric visibility range
degradation has become an environmental issue in most urban
areas in China. PM2.5 are believed to be mostly responsible forthe scattering and absorption of visible light and to cause thedecrease of visibility. In the paper, an accurate and sensitive
cavity attenuated phase shift spectroscopy (CAPS) sensor wasused to monitor the atmospheric visibility. The optical sensor
mainly includes a LED light source, a band-pass filter, an opticalresonant cavity (composed of two high mirror, reflectivity isgreater than 99.99%), a photoelectric detector and a lock-in
amplifier. The 2L / min flow rate, the optical sensor rise and fall
response time is about 15 s, so as to realize the fast measurementof visibility. For a month to monitor the air quality in Hangzhou,
atmospheric visibility measurement results from optical sensor,
PM10 and PM2.5 mass from Hangzhou monitoring station
standard analysis equipment. Air temperature and humidity datas
are also from the monitoring station. The monitoring results
show that the correlation between the atmospheric extinction
coefficient and PM is very high, and the correlation between theextinction coefficient and PM10 is more than 0.9. Elevated PM2.5
mass was associated with visibility (Vr<10 km), and a PM2.5
threshold value of 90µg /m3 (i.e., low visibility occurs whenPM2.5 > 90 µg /m3).

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Haoran Sun, Yong Yao, Harbin Institute of Technology(Chile)A new pilot structure is developed aiming at improving both
spectral efficiency and accuracy. Two groups of scattered pilots
are inserted in one training symbol. In each group, the scatteredpilots are inserted with the same space just like the conventional
scattered pilots.
For each group, the scattered channel response corresponding
to the scattered pilots are firstly estimated through LS algorithm.
Secondly, the whole channel response is estimated through linear
interpolation.Then intra-symbol frequency domain averaging
method is used to further improve the accuracy. What sets itapart from the conventional method is we take the average of thetwo groups’ channel response.
We have simulated the channel equalization method in CO-OFDM
transmission systems and numerically studied its transmission
performance over a 100 km optical fiber link at 40 Gb/s.For
convenience we define the pilot filling ratio as ?=(pilot number)/(subcarrier number). It is found that the proposed method havea 0.25dB improvement performance relative to the conventional
method when ? is both 50 ? to achieve the BER of 10-3 . The
proposed ?=17? offers a similar performance to the conventional?=50?, and has about 0.5dB and 1.1dB improvement correspondto the conventional ?=33? and ?=25? to achieve the BER of
10-3. The spectral efficiency of the proposed method has been
improved considerably.

10026-50, Session Post

Video coding for 3D-HEVC based on
saliency information
Fang Yu, Ping An, Shanghai Univ. (China)
As an extension of High Efficiency Video Coding ( HEVC),
3D-HEVC has been widely researched under the impetus of the
new generation coding standard in recent years. Compared with
H.264/AVC, its compression efficiency is doubled while keeping
the same video quality. However, its higher encoding complexityand longer encoding time are not negligible. To reduce thecomputational complexity and guarantee the subjective qualityof virtual views, this paper presents a novel video coding method
for 3D-HEVC based on the saliency information which is an
important part of Human Visual System (HVS). First of all, therelationship between the current coding unit and its adjacentunits is used to adjust the maximum depth of each largest coding
unit (LCU) and determine the SKIP mode reasonably. Then,
according to the saliency information of each frame image, thetexture and its corresponding depth map will be divided into
three regions, that is, salient area, middle area and non-salientarea. Afterwards, different quantization parameters will beassigned to different regions to conduct low complexity coding.
Finally, the compressed video will generate new view point
videos through the renderer tool. As shown in our experiments,
the proposed method saves more bit rate than other approaches
and achieves up to highest 38% encoding time reduction without
subjective quality loss in compression or rendering.

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Conference 10026: Real-time Photonic Measurements,
Data Management, and Processing II

10026-51, Session Post

potentially applicable for identifying biomedical samples such as
blood cells and cancer cells.

Research on the laser tracking system formeasuring moving target based on APD
Liu Hua, Liu Ke, Yinxiao Miao, Beijing Aerospace Institutefor Metrology & Measurement Technology (China)
In order to measure the coordinate of moving target, thelaser tracking system for measurement of moving target was
proposed,in which the receiver of four-quadrant APD was
adopted as the detector and the DC motor was used to drive
the reflector to move in two dimensions. The principle of themeasurement system was analyzed first.Then the main part ofthe system was introduced.The tracking experiment showed that
,this system could realized the function of automatic tracking
and measuring the coordinate of moving target according to thepulsed laser ranging and angle sensors.

10026-21, Session 5

High-throughput optofluidic microalgal
cell analyzer with single-cell resolution forbiofuel production (Invited Paper)
Cheng Lei, The Univ. of Tokyo (Japan); Takuro Ito, Keio
Univ. (Japan); Dino Di Carlo, Univ. of California, Los
Angeles (United States); Yasuyuki Ozeki, Keisuke Goda,
The Univ. of Tokyo (Japan)

The time-stretch imaging system has the capability of ultrafast information acquisition. We demonstrate a 38.88 MHz
line-scan time-stretch imaging system in which multiplexing
detection scheme is used to double the number of pixels. A
20 GS/s sampling rate is achieved by employing a 10 GS/selectronic digitizer so that aliasing problem can be addressed.
The proposed scheme can improve the image quality by 4.16
dB comparing to the conventional system and has a better
performance of at least 2.3 dB image enhancement in contrast to
the numerical interpolation and re-sampling techniques.

The development of reliable, sustainable, and economical sourcesof alternative fuels is an important, but challenging goal for
the world. As an alternative to liquid fossil fuels, algal biofuelis expected to play a role in solutions to global warming sincealgae absorb atmospheric CO2 via photosynthesis. Among
various algae for fuel production, Euglena gracilis is an attractive
microalgal species as it is known to produce wax ester andtriacylgricerol within lipid droplets. To date, while there exist
many techniques for inducing microalgal cells to produce lipid
with high efficiency, few analytical methods are available forcharacterizing a heterogeneous population of such lipid-induced
microalgae including E. gracilis with single-cell resolution. To
address the need, we demonstrate a high-throughput label-freesingle-cell image analyzer at 15,000 cells/s based on time-stretch
microscopy and microfluidic techniques for classifying live lipidinduced E. gracilis cells under different culture conditions. From
our statistical image analysis, we identify cell-to-cell differences
in intracellular phenotypes between various culture conditions
including nitrogen deficiency for lipid induction. This result
indicates that our method is an effective tool for evaluating theoutcome of lipid induction techniques in a rapid and non-invasive
manner and holds promise for optimizing the efficiency of biofuel
production based on E. gracilis and potentially other microalgae.

10026-20, Session 510026-22, Session 5

High-throughput optofluidic profiling of
euglena gracilis with morphological andchemical specificity (Invited Paper)

Four-dimensional visualization of asmall-scale flame based on deflection
tomography (Invited Paper)

10026-19, Session 5

Time-stretch imaging system with OTDM
detection scheme (Invited Paper)
Xu Wang, Heriot-Watt Univ. (United Kingdom); Bo Dai,
Univ. of Shanghai for Science and Technology (China)

Baoshan Guo, Cheng Lei, Takuro Ito, Yiyue Jiang, Yasuyuki
Ozeki, Keisuke Goda, The Univ. of Tokyo (Japan)
The world is faced with environmental problems and the energy
crisis due to the combustion and depletion of fossil fuels.
The production of biofuel from Euglena gracilis is expected
to become a practical solution due to their fast growth rates
and cultivation on non-arable land areas. However, their lipid
productivity is still a problem for E. gracilis to be an economicallyrealistic biofuel feedstock. One potential way is to use lipidinduced E. gracilis. Hence, effectively classifying the lipid-induced
E. gracilis is necessary for high-efficiency biofuel production.
Here we present a high-throughput optofluidic Euglena gracilis
profiler which consists of an optical time-stretch microscope anda fluorescence analyzer on top of an inertial-focusing microfluidic
device that can detect fluorescence from lipid droplets in theircell body and provide images of E. gracilis cells simultaneously
at a high throughput of 10,000 cells/s. Lipid-induced and fresh
E. gracilis are used as an example. With the multi-dimensional
information, we can classify the lipid-induced E. gracilis cells
from fresh cells more precisely than traditional microscopy andfluorescence analysis without sacrificing throughput. The error
rate of identifying lipid-induced E. gracilis can drop to ~1%, whichis over 10% with only one-dimensional information. This method
provides a promise for evaluating the efficiency of lipid-inducing
techniques for biofuel production. The integrated system is also

198

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Bin Zhang, Zhigang Liu, Minmin Zhao, Qingdao Univ. of
Science and Technology (China)
Optical computed tomography plays an important role invisualizing and diagnosing various ﬂow ﬁelds. Deflection
tomography with limited angle projections was investigated tovisualize a small-scale premixed flame. A projection samplingsystem for deflection tomography was presented to obtainthe chronological deflectograms with a pair of gratings. The
deflectograms were processed based on wave-front retrieval toobtain the deflection angles of the rays. This two-dimensional
data extraction method expanded the usability of deflection
tomography and was suitable for the projection extractionof small-scale combustion. Temperature distributions in 10
cross sections for each deflectogram were reconstructedin different instants. The Sobel operator was applied to thethreshold segmentation of two-dimensional temperature
distributions. Visualization tool kit with the marching cube andray casting algorithms was employed to reconstruct the flow
structure. The experiment demonstrated three-dimensional
dynamic visualization of the temperature distributions and theflame structures of a small-scale premixed combustion. The
experimental reconstruction was then compared with the result
obtained from computational fluid dynamic analysis.

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Conference 10026: Real-time Photonic Measurements,
Data Management, and Processing II

10026-23, Session 510026-25, Session 5

Morphology-based cancer detection with
optofluidic time-stretch microscopy

Survey of the baseline correction
algorithms for real-time spectroscopy
processing

Hirofumi Kobayashi, Cheng Lei, Ailin Mao, Yiyue Jiang,
Baoshan Guo, Keisuke Goda, The Univ. of Tokyo (Japan)
Cancer cell detection plays an important role in biomedical
research and clinical diagnosis. It is believed that cancer
metastasis, which is the primary cause of cancer deaths, occurs
via circulating tumor cells (CTCs) – precursors to cancer thattrigger the spread of cancer. Detecting CTCs in the blood is
expected to be helpful for cancer diagnosis and treatment at
its early stage. However, CTCs are extremely rare, and hence,
it takes a considerable amount of time to detect CTCs withcurrent methods, such as centrifugation, inertial focusing, andfluorescence- or magnetic-activated cell sorting, which either
have low throughput, low specificity, or low sensitivity. To addressthese problems, we propose and experimentally demonstratemorphology-based cancer detection with optofluidic time-stretch
microscopy using breast cancer cells (MCF-7). By properly
controlling the condition of the treatment, MCF-7 cells express
unique morphological changes, which can be used as naturalmorphological markers for our image-based detection. Our
optofluidic time-stretch microscope consists of a time-stretch
microscope with a high spatial resolution of 780 nm at a 1D
frame rate of 75 MHz, a microfluidic device that focuses andorders cells, and an image analyzer that identifies the cancer
cells from blood cells via the morphological biomarkers. With
these biomarkers, we successfully detect breast cancer cells
spiked in blood cells with a high throughput of 10,000 cells/s. The
technique holds great promise for cancer diagnosis.

Yuanjie Liu, Yude Yu, Institute of Semiconductors (China)
In this paper, we will survey and evaluate several widely usedbaseline correction algorithms, including Shirley background,
CROMWELL, LIMPIC, airPLS, AIMA and corner cutting methods.
These algorithms are able to detect the baseline drift of one
dimensional spectroscopy data trace and remove it automatically.
However, each method has particular range for application. Someare limited to the monotone decreasing assumption, some are
not able to treat the situation when baseline behaves complex
fluctuation. This paper will analyze the function and performanceof each method, summarize each one’s features and draw a clear
map for understanding the defects and advantages for the choiceof them in practical use. The baseline correction approaches are
categorized according to several patterns, for example, by thebasic techniques based on: wavelet decomposition, polynomial
fitting or adaptive integration; then, by their computing manners:
global iteration, key points interpolating or random mixing.
Finally, all of these algorithms will be tested and evaluated undera specific criteria- SVM gap gain, for performance ranking. The
evaluating procedure will assess each algorithm quantitatively topresent an order for choice under various situation. This result
will be the first time to propose a concrete list for guidancein baseline correction processing when carrying out practical
spectroscopy analysis.

10026-26, Session 510026-24, Session 5

High-throughput time-stretch imaging
cellular assay based on a DVD spinningplatform
Anson H. L. Tang, Antony C. S. Chan, Kelvin C. M. Lee,
Edmund M. Y. Lam, Kenneth K. Y. Wong, Kevin K. Tsia, The
Univ. of Hong Kong (Hong Kong, China)
Innovations in imaging flow cytometry together with biochemicallabeling technologies have successfully realized high throughput
single-cell monitoring with multiparametric diagnostics. However,classical approaches still run short of extracting biophysicalknowledge of cells. Several approaches have been establishedfor cell biomechanics studies, for example, cell stiffness studies
through microfluidic forces, and adherent force determination
by non-imaging spinning disk system. The throughput of theseimage-based methods is primarily limited by the compromise
between static field-of-view (FOV) and imaging speed (fps)in standard imaging sensors. Alternative methods such as
automated microscope systems incorporating high-speed cameraand mechanical scanning devices can image with a large FOV
without sacrificing image resolution. However, the throughput isstill inherently bottlenecked by the mechanical inertia. We herereport a new type of imaging cellular assay on which the cells
are fixed on a solid spinning substrate at known radial position
and rotational speed. We implement this assay by modifying
a commercial digital versatile disc (DVD) drive such that therotational speed can arbitrarily and stably controlled. Human
breast cancer cells (MCF-7) are pre-cultured on polycarbonate
substrates, which are essentially the commercial DVD, andimaged under high spinning speed (900 rpm). The system,
integrated with time-stretch imaging, can provide cellular
resolution (~2 µm in radial direction) at high line-scan rate (11MHz) and wide arbitrary spinning rate (900-4000 rpm). We also
discuss strategies to implement studies on circulating tumor cells(CTC) based on our current system.

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Automated classification ofphytoplanktons based on time-stretch
imaging
Queenie Tsz Kwan K. Lai, Andy K. S. Lau, Kelvin C. M. Lee,
Anson H. L. Tang, Kenneth K. Y. Wong, Kevin K. Tsia, The
Univ. of Hong Kong (Hong Kong, China)
Optical time-stretch imaging can capture single-cell images withhigh sensitivity (e.g. high resolution) and throughput (>MHzline scan rate). With such advantages, optical time-stretch
imaging flow cytometry has profound impact in the biomedical(e.g. rare cancer cell detection) and biological research fields.
However, its potential in marine research has not been fully
explored. Phytoplankton serves as foundation of carbon cycleand ecosystem, and a remarkable indicator for the aquatic system
health and water quality but there is lack of efficient methods
for profiling single-cell of phytoplankton other than manual
inspection. Optical time-stretch imaging could fulfil the unmet
need to classify and count ultralarge-scale phytoplankton withsingle-cell analysis in marine or biofuel research. So far, twoclass classification involving manual inspection (e.g. gating) has
been the common approach implemented with time-stretch
imaging flow cytometry. These current methods are however
incompatible with the need for multi-class classification onlarge amount of images with cells of multiple classes. We herereport an automated multi-class classification of phytoplankton
based on high-resolution time-stretch imaging. Specifically, we
extracted a total of 40 features from the grey-scale time-stretch
images including various geometrics – size, circularity, elongation
factor and morphological information – contrast, energy ,entropy
as higher dimensional features for automated classification byusing support vector machine (SVM) as the training approach
to identify more than 10 species of phytoplankton with a crossvalidated accuracy of >90%. Optical time-stretch imaging flow
cytometry could be an efficient and effective tool to achieve
single-cell counting and analysis, especially for continuous
monitoring of the aquatic system from tidal to seasonal.
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199

Conference 10026: Real-time Photonic Measurements,
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10026-27, Session 5

Research of aerial imaging spectrometerdata acquisition technology based on USB
3.0
Junze Huang, Shanghai Institute of Technical Physics of
the Chinese Academy of Sciences (China) and Shanghai
Univ. (China); Yueming Wang, Shanghai Institute ofTechnical Physics of the Chinese Academy of Sciences(China)10026-29, Session 6

New method of writing long-period fiber
gratings using high-frequency CO2 laserWith the emergence of UVA (unmanned aerial vehicle) platform
for aerial imaging spectrometer,research of aerial imaging
spectrometer DAS(data acquisition system) faces new challenges.
Due to the limitation of platform and other factors, the aerial
imaging spectrometer DAS requires Light-weight and compact,low-cost and universal. Traditional aerial imaging spectrometer
DAS system is expensive, bulky, non-universal and unsupported
plug-and-play based on PCIe.So that has been unable to meetpromotion and application of the aerial imaging spectrometer.
In order to solve these problems, the new data acquisition
scheme bases on USB3.0 interface.USB3.0 can provide
guarantee of Light-weight and compact, low-cost and universal
relying on the forward-looking technology advantage. USB3.0transmission theory is up to 5Gbps.And the GPIF programming
interface achieves 3.2Gbps of the effective theoretical data
bandwidth.USB3.0 can fully meet the needs of the aerial imaging
spectrometer data transmission rate.The scheme uses the slave
FIFO asynchronous data transmission mode between FPGA andUSB3014 interface chip. Firstly system collects spectral datafrom TLK2711 of high-speed serial interface chip.Then FPGA
receives data in DDR2 cache after ping-pong data processing.
Finally USB3014 interface chip transmits data via automatic-dma
approach and uploads to PC by USB3.0 cable.
During the manufacture of aerial imaging spectrometer, the DAS
can achieve image acquisition, transmission, storage and display.
All functions can provide the necessary test detection for aerial
imaging spectrometer. The test shows that system works stably
and no data lose. Average transmission speed and storage speedof writing SSD can stabilize at 1.28Gbps . Consequently ,this dataacquisition system can meet application requirements for aerial
imaging spectrometer.

Gaoran Guo, Institute of Semiconductors (China); Ying
Song, Shijiazhuang Tiedao Univ. (China); Wentao Zhang, Li
Fang, Institute of Semiconductors (China)
Long period fiber grating (LPFG) has found increasing
application in optic communication and sensing systems. LPFGs
are widely used to fabricate fiber sensors, gain-flattening filters,
wavelength rejection filters, and tunable filters because of its
advantages, such as the low insertion losses, low backgroundback-reflection, polarization independence, and relatively simple
fabrication. LPFG allows light coupling between the fundamental
mode and the cladding modes in the same direction, which
results in several attenuation bands centered at discrete
wavelengths in the transmission spectrum.
In the paper, the LPFGs were fabricated in a single-mode fiberusing a high frequency CO2 laser system through the pointto-point technique. The experimental setup consists of a CO2
laser controlling system, a beam and a focusing system locatedat a motorized translation stage, a fiber alignment stage, and ameasuring system for the transmission spectrum of the LPFG.
In our configuration, the period of the LPFG is precisely
controlled by periodically turning on/off the laser shutter andmeanwhile the motorized translation stage is driven to move
forward at a constant speed. The heating process is more stablein this way. For LPFG’s spectrum measurement, an amplified
spontaneous emission (AE) source and an optical spectral
analyzer (OSA) are used. The experiment of one-time writing
LPFG is performed. It not only improves the efficiency of fiber
writing process, but also solves the problem of point-to-point
mismatching in the conventional multi-writing process.

10026-30, Session 610026-28, Session 6

Two-step phase-shifting SPIDER

GeSn/SiGeSn photonic devices for midinfrared applications: experiments andcalculations (Invited Paper)

Shuiqin Zheng, Shixiang Xu, Shenzhen Univ. (China)

Genquan Han, Xidian Univ. (China); Qingfang Zhang,
Chongqing University (China); Yan Liu, Xidian University(China); Chunfu Zhang, Xidian (China); Yue Hao, Xidian
Univ. (China)
GeSn and SiGeSn alloys as the new photonic materials for midinfrared optoelectronic monolithic integration have attracted
tremendous interests, for their tunable bandgap and thecompatibility with Si CMOS technology. Adding Sn to Ge to form
the GeSn alloy can cause the lowering of the bandgap and thetransition of indirect-to-direct bandgap, which can promote thered-shift of the cut-off wavelength and the emission peak at
the same time. We will report the experimental results of GeSn
photodetectors with operation wavelength in 2~5 ?m midinfrared
region, which have many potential applications, such as chemicalbiological-physical sensing, medical diagnostics, environmental
monitoring, active imaging, and free-space laser communications.
Furthermore, applying tensile strain to GeSn can lead to a further
red-shift by lowering the energy of ? conduction valley. In thiswork, we also introduce the novel tensile strained GeSn/SiGeSn
200

detector, modulator, and LED/laser devices wrapped in Si3N4
liner stressor for mid-infrared optoelectronic applications. As
the releasing of the residual stress in Si3N4 liner, a large tensile
strain is induced into GeSn layer, which will significantly improvethe device performance and shift the operation wavelength tomidinfrared region.

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Comprehensive characterization of ultrafast optical field iscritical for ultrashort pulse generation and its applications. This
paper presents a novel method to improve the optical-fieldreconstruction of ultrashort pulses by combining two-stepphase-shifting (TSPS) with the spectral phase interferometryfor direct electric-field reconstruction (SPIDER). The method
records two spectral interferograms with π phase-shifting to
remove experimentally the effect of the dc portion occurring in
traditional SPIDER method. Our results show the method canremove experimentally the effect of the dc portion occurringin traditional SPIDER method. Compared with the traditional
SPIDER measurement, the method makes the reconstructedresults be much less disturbed by the time delay ? between thetest pulse replicas and the width of filtering temporal window ?w,
so the measurements become more reliable and robust. What ismore, the absence of the dc component allows SPIDER device
to work efficiently even the time delay ? is so small that strong
overlap happens between the dc and ac portions. Consequently,
the SPIDER device can choose ? more flexibly, which extends no
doubt the ability of the SPIDER device to characterize the pulses
both with complicated temporal/spectral structures and withnarrow bandwidth. We believe this work will not only enlarge thewww.spie.org/pa·

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Conference 10026: Real-time Photonic Measurements,
Data Management, and Processing II
application fields of SPIDER, but also be very helpful to improvethe diagnosis quality of ultrashort pulses for the laboratories
possessing a traditional SPIDER device, because our TSPSSPIDER just needs actually a traditional SPIDER device plus aquarter-wave plate.

10026-31, Session 6

The study of in-line DFB-tunable laser
based on REC techniqueRenjia Guo, Hao Wang, Jun Lu, Yuechun Shi, Xiangfei
Chen, Nanjing Univ. (China)
An in-line structure, current-tuned tunable laser based on REC
technique is design, test and studied. Through 3 in-line DFB
lasers with a wavelength spacing of about 3.2nm, continues
tuning range of about 11nm is obtained. At the temperature of 20°C, each laser can be tuned about 3.4-3.6 nm with SMSRs over
35 dB from 30 to 170 mA, and the tuning speed is about 10-30
microseconds, which is much faster than that by the thermalelectric cooler (TEC). The algorithm to obtain an equal output
power in such current tuning is also studied for this in-line laser.
The results may help to realize very low cost tunable lasers in the
future.

The detection of very low-power radio-frequency (RF) signals ina cluttered environment is very important in many applications
such as electronic warfare and radio astronomy. Photonic
technique offers a potential way to implement the role withthe advantages of wide band, small size and immunity toelectromagnetic interference. In this paper, a novel method
to detect low-power RF signals with the frequency selective
amplification is proposed and experimentally demonstrated.
The detection system is assembled with a tunable optoelectronic
oscillator (OEO), which is mainly composed of a tunable laser
source, a phase modulator and a phase-shifted fiber Bragg
grating (PS-FBG) with a narrow notch in the reflection band.
The principle to detect low-power signal is: The OEO works at
the threshold state. When the low-power RF signals are fed to
the RF input port, the RF signal with a frequency matching theoscillation frequency of the OEO is selected and amplified by
the oscillation gain. The oscillation frequency can be tuned bychanging the frequency difference between the frequency of the
TLS and the notch frequency of the PS-FBG.
The proposed low-power RF signal detection system is evaluated.
The results show that the established tunable OEO can detect
the RF signal as low as -75 dBm with a dynamic range of 80 dB.
The RF signal with frequency from 1.5 to 4.5 GHz is selectively
detected with a gain of about 7 dB. The detectable frequency
range could be extended by a PS-FBG with a large reflectionband.

10026-32, Session 610026-35, Session 7

Characterization of phase-shifted Brillouin
dynamic gratings in a polarization
maintaining fiber

Fiber-optic sensing system forsimultaneous measurement of
temperature and transversal loading basedon a microwave photonic filter

Dengwang Zhou, Yongkang Dong, Pengbai Xu, Lei Teng,
Harbin Institute of Technology (China); Hongying Zhang,
Harbin Univ. of Science and Technology (China); Zhiwei
Lu, Harbin Institute of Technology (China)
We numerically calculate and experimentally investigate thecharacterization of phase-shifted Brillouin dynamic gratings (PSBDGs) in a polarization maintaining fiber (PMF). A phase shifted
point is induced into the middle of a conventional BDG throughphase-modulating one of the two pump pulse, generating a
PS-BDG thanks to the stimulated Brillouin scattering (SBS).
When the frequency difference between a high frequency pump1
pulse with 1ns and π-1ns and a low frequency pump2 pulse with
100ps is equal to the Brillouin frequency shift of the PMF, atransient PS-BDG with a 3dB-bandwidth of 354MHz of the notch
spectrum is simulated based on the coupled-wave equationsof BDG. By increasing the repetition rate up to 250MHz, anenhanced PS-BDG with a deep notch depth is obtained since theresidual acoustic wave of the former SBS process is enhancedby the optical waves of the latter SBS process. Then a proof-ofconcept experiment is built to verify the transient PS-BDG and
the results show that the notch feature is consistent with thesimulation results and the notch frequency of the PS-BDG canbe changed by tuning the phase shift . The proposed PS-BDGshave important potential applications in optical fiber sensing,microwave photonics, all-optical signal processing and RoF(radio-over-fiber) networks.

10026-33, Session 7

Detection of low-power RF signals using atunable optoelectronic oscillator

Shiwei Zhang, Rui Wu, Hao Chen, Hongyan Fu, Xiamen
Univ. (China)
Fiber-optic sensors have attracted much research attention due
to their overwhelming advantages, and have been successfully
applied to remote sensing and parameter measuring. In
this paper, a fiber-optic sensing system for simultaneous
measurement of temperature and transversal loading based on asingle-passband RF filter has been proposed and experimentallydemonstrated. This sensing system consists of a fiber MachZehnder Interferometer (FMZI) as the sensing device and adispersive medium. The FMZI also acts as the spectrum slicer toinduce continuous sampling, which results in the single-passband
frequency response together with the dispersive medium. Twoarms of the FMZI are used to measure the temperature andtransversal loading respectively. The temperature changes on
one arm will introduce the variation of refractive index, which willchange the central frequency of the RF filter’s passband, while
the transversal loading will induce the change of polarization
state of the light transmitted in the other arm, and thus theamplitude of the RF filter’s passband will be changed accordingly.
By tracking the central frequency and the amplitude changes of
the RF filter’s passband, the temperature and transversal loading
can be monitored simultaneously. With the proposed fiberoptic sensing system, the temperature and transverse loading
variation induced optical spectra changes can be converted
to the variation of frequency and amplitude of the RF filter’s
passband, which greatly facilitates the measurement. Meanwhile,
this proposed sensing system is simple in construction, easy to
implement and suitable for multiplexing and remote sensing, thus
shows good potential in practical applications.

Yuchen Shao, Dalian Univ. of Technology (China); Ming
Li, Institute of Semiconductors (China); Xiuyou Han,
Mingshan Zhao, Dalian Univ. of Technology (China)

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201

Conference 10026: Real-time Photonic Measurements,
Data Management, and Processing II

10026-36, Session 7

Pump sweeping time evaluation of
stimulated Brillion scattering-based
rectangular optical filter
Mengyue Shi, Lilin Yi, Wei Wei, Weisheng Hu, Shanghai
Jiao Tong Univ. (China)
Optical narrowband filtering ranging from MHz to several
GHz plays an important role in high-resolution optical signal
processing, especially in the context of flexible switching in highspeed optical transmission systems [1] and band-pass filteringin microwave photonics [2]. An ideal tunable passband filter
has a rectangular response consisting of an ultra-flat passband
and very steep edges which bring about many benefits. We
have realized rectangular optical filters with tunable bandwidthfrom 50MHz to 4GHz based on stimulated Brillouin scattering(SBS) in optical fiber [3-4]. Both multi-tone pump and sweeping
pump schemes have been used to generate rectangular Brillouinpump spectra and feedback control scheme has been used
to compensate the non-flat frequency response of the used
opt-electronics components therefore achieving rectangular
SBS gain spectra. In comparison, sweeping pump scheme canachieve better rectangular shape since no four-wave mixing(FWM) effects happen within pump spectra therefore no out-ofband SBS gain is generated. The pump sweeping time is a key
parameter to achieve both flat spectral response and acceptablesignal performance. In the previous experiment, the frequency
sweeping duration is set at 1 us, which is much shorter than
the signal propagation time in fiber and can achieve effective
feedback compensation as well [4]. The seeping time is very
important especially for short-fiber cases. However, the optimalpump sweeping time has not been extensively studied yet.

202

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Conference 10027:
Nanophotonics and Micro/Nano Optics III
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10027 Nanophotonics and Micro/Nano Optics III

10027-203,

Quantum dot photonics: from science topractical implementation
Yasuhiko Arakawa, Institute of Industrial Science, The
Univ. of Tokyo (Japan) and Institute for Nano Quantum
Information Electronics, The Univ. of Tokyo (Japan)
Recent advances in growth and physics of quantum dots
have led to the commercialization of quantum dot lasers fortelecommunications and other applications. Moreover, single
quantum dots coupled to photonic crystal nanocavities haveenabled the investigation of fundamental physics such as
solid-state cavity quantum electrodynamics (QED). In thispresentation, we discuss the current state of the art of quantum
dot lasers, and also future prospects including their application
to hybrid silicon photonics and the development of ultra-small
nanolasers. We also describe the demonstration of a single
photon emission from a III-Nitride nanowire-based quantum dot
operating above room temperature.

10027-1, Session 1

Recent advances in chip-scale grooming
optical data processing on silicon platform(Invited Paper)
Jian Wang, Huazhong Univ. of Science and Technology(China)Silicon photonics is considered to be a promising photonic
integration platform enabling chip-scale optical data processing.
We will review our recent advances in chip-scale grooming
optical data processing on silicon platform. Using designed andfabricated silicon nanophotonic devices, we demonstrate various
optical data processing functions: 1) chip-scale wavelength/polarization/mode (de)multiplexing; 2) chip-scale wavelength
conversion of advanced modulation formats; 3) chip-scalebidirectional optical data exchange; 4) chip-scale two-input
and three-input high-base optical computing (addition,
subtraction, hybrid addition/subtraction); 5) chip-scale opticalcoding/decoding; 6) chip-scale optical signal regeneration. The
experimental results show favorable operation performance ofchip-scale grooming optical data processing on silicon platform.

10027-2, Session 1

Group IV compounds for micrometre scale
device and systems (Invited Paper)
Frederic Y. Gardes, Univ. of Southampton (United
Kingdom)computers (HPCs). Silicon optical switches have advantages ofbeing compact and CMOS process compatible, which can beeasily monolithically integrated. However, there are difficulties toconstruct large ports silicon optical switches. One of them is thenon-uniformity of the switch units in large scale silicon opticalswitches, which arises from the fabrication error and causes
confusion in finding the unit optimum operation points. In thispaper, we proposed a method to detect the optimum operating
point in large scale switch with limited build-in power monitors.
We also propose methods for improving the unbalanced crosstalkof cross/bar states in silicon electro-optical MZI switches andinsertion losses. Our recent progress in large scale silicon opticalswitches, including 64 ? 64 thermal-optical and 32 ? 32 electrooptical switches will be introduced. To the best our knowledge,
both of them are the largest scale silicon optical switches in theirsections, respectively. The switches were fabricated on 340-nm
SOI substrates with CMOS 180-nm processes. The crosstalk of
the 32 ? 32 electro-optic switch was -19.2dB to -25.1 dB, while thevalue of the 64 ? 64 thermal-optic switch was -30 dB to -48.3 dB.

10027-4, Session 1

Silicon photonics process development
based on a 200-mm CMOS platform
Zhihua Li, Jiang Yan, Bo Tang, Guilei Wang, Lingkuan
Meng, Institute of Microelectronics (China)
Silicon photonics, which takes advantages of the mature silicon
CMOS manufacturing infrastructure, has attracted much attention
for its potential to realize massive commercial application in
optical communication and interconnection. Though compatible
with Si CMOS process is the greatest advantage for silicon
photonics compared with other photonic devices based on III-V
compound semiconductor or planar lightwave circuit (PLC),
there are some different processes between silicon photonics
and silicon CMOS that need to be developed before reliablesilicon photonics fabrication. In this paper, the process difference
between silicon photonics and silicon CMOS is discussed andprocess development for silicon photonics based on a 200 mm
CMOS platform is presented. Firstly, the sensitivity of processparameters of waveguide is studied which are not attached somuch importance in CMOS process. Process control including
waveguide dimension, Line-edge roughness (LER), steepness andetching without stop layer are then introduced. Ion implantation
for photonic active devices can be transferred from existing
CMOS process module, but the implant depth and density
should be adjusted according to the device structure, which
is analyzed next. The germanium process is applied in CMOS
fabrication to improve the carrier mobility in recent years and it
can also be used for silicon photonics to integrate photodector.
The optimization of germanium epitaxy on silicon and electrodemetallization for photodector purpose is presented. Finally, acomplete silicon photonics process flow including passive andactive components developed in our 200 mm CMOS platform ispresented.

No Abstract Available

10027-5, Session 1
10027-3, Session 1

Large-scale silicon optical switches for
optical interconnection (Invited Paper)
Lei Qiao, Tao Chu, Chinese Academy of Sciences (China)
Large-scale optical switches are greatly demanded in building
optical interconnections in data centers and high performance

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Double Doppler effect in two-dimensional
photonic crystal with negative effectiveindex
Qiang Jiang, Jiabi Chen, Binming Liang, Songlin Zhuang,
Univ of Shanghai for Science and Technology (China)
Inverse Doppler effect in photonic crystal (PhC) was proved#PhotonicsAsia

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Conference 10027:
Nanophotonics and Micro/Nano Optics III
experimentally by our team in 2011. In this paper, we studied
the double Doppler effect in PhC with negative refractive index,
using a triangular silicon rod array prism with a vertex angleof triangle geometry of 30°. The FDTD simulation showed
the normal incident light exits from the slope of PhC on bothsides of the normal of the slope. The main spatial harmoniccomponents were extracted from the Bloch wave propagatingin the photonic crystal by using Fast Fourier Transform andinverse Fourier Transform.The phase evolution of these twomain harmonic components were analyzed, one of them showed
unusual character that the direction of phase velocity is opposite
to the wave vector direction, as vp·k <0, which leads to thenegative refraction, and the other showed normal feature, as
vp·k >0, leading to the normal refraction. To verify the Doppler
phenomenon in this photonic crystal, a dynamic FDTD method
was improved, in which the electric field data and magnetic fielddata of the former time were added to the newly field data of
the later time to form a new field data as the initial field for eachobject moving step. With this new FDTD method, the Doppler
effect was studied at four different velocities, as 0.005c, 0.008c,
0.02c and 0.05c. The simulation exhibited the normal and inverse
Doppler effect happened in this photonic crystal simultaneously,
and the simulative Doppler frequency shifts were consistent withthe theoretical values

such as the miniature in volume and simplicity in structures. In
recent years, the polymer materials have been used in random
lasers for their high luminescence efficiency. The amplified
spontaneous emission is an important property when thepolymer material is lighted by external pump laser.

10027-6, Session 2

Erbium integration in silicon-slottedphotonic devices for light amplification

III-V quantum dot lasers monolithicallygrown on Si platform (Invited Paper)

In this paper, a polymer fiber was constructed by siphoning
the xylene solution of a polymer into a capillary tube with 300?m inner diameter. After the solvent evaporating, the polymer
fiber was lighted by an external pump beam and the amplified
spontaneous emission (ASE) of the polymer fiber is investigated.
The optical photos show the details of polymer fiber. The
emission spectra are recorded, and the intensity and the full
width at half maximum (FWHM) as a function of pump power
intensity are analyzed. The absorption coefficient of polymer
F8BT is obtained from a polymer F8BT film with a thickness of
200 nm. For the high absorption of polymer, the pump beam can
not penetrate the long F8BT fiber. However the ASE can been
detected along the fiber for the low absorption around 567 nm.
The sketch up diagram and an optical photo show it in vividly.
This fabrication method provides a cheap way for application of
micro polymer fiber.

10027-9, Session 2

Weiwei Zhang, Univ. Paris-Sud 11 (France); John Rönn,
Aalto Univ. (Finland); Lasse Karvonen, Aalto Univ. Schoolof Electrical Engineering (Finland); Meiling Zhang, Jilin
Univ. (China); Samuel Serna, Xavier Le Roux, Univ. ParisSud 11 (France); DingShan Gao, Wuhan National Lab.
for Optoelectronics (China); Daming Zhang, Jilin Univ.
(China); Antti Säynätjoki, Aalto Univ. (Finland); Laurent
Vivien, Eric Cassan, Univ. Paris-Sud 11 (France)

Huiyun Liu, Jiang Wu, Univ. College London (United
Kingdom)
No Abstract Available

10027-7, Session 2

Optical deposition of topological insulator
bismuth telluride for Q-switched ytterbium
fiber laser
Muhammad Aizi Mat Salim, Univ. of Malaya (Malaysia)
and Univ. Teknologi Malaysia (Malaysia); Harith B. Ahmad,
Saaidal Razali Azzuhri, Mohd Zulhakimi Ab Razak,
Sulaiman Wadi Harun, Univ. of Malaya (Malaysia)
We have demonstrated a Q-switched ytterbium-doped fiber laser(YDFL) based on a few-layer bismuth telluride Bi2Te3 saturable
absorber (SA). A few layer bismuth telluride within a suspension
was bringing onto a fiber ferrule through an optical deposition
method at room temperature. Stable pulsed was obtained at 88.6
mW pump threshold. The Q-switched repetition rate varied from17.00 to 29.63 kHz. The maximum pulse energy and narrowest
pulse width were 3.37 nJ and 14.54 ?s respectively. Therefore, thisshowed that bismuth telluride was also well suited at 1 ?m region,and considered as a potential saturable absorber for generationof short pulses.

Achieving light sources and light amplification in silicon
photonics has met several challenges for now due to the silicon
indirect bandgap. Alternatively, light sources in silicon photonic
circuits have been realized through hybrid integration of III-V
semiconductor materials and strained Ge layers on silicon.
These kinds of hybrid integration routes rely on semiconductor
techniques, either by epitaxial growth or hetero-bonding of diesor wafers. Another possible route is based on the integrationof active soft-materials (eg polymers) or oxides by lighter
techniques like spin-coating or CVD processes. Therefore,
low cost, hybrid integration of these active materials, suchas Er3+ doped materials, semiconductor carbon nanotubes,
quantum-doped polymers, etc, has been recently studied forthe demonstration of various integrated functions [1] [2]. Er3+
materials, for example, which emit light covering telecom C&L
bands, have recently been used to demonstrate high net gain up
to 31dB/mm in submicron silicon wires [1]. Such promising results
indicate that integrating Er-materials in silicon nanophotonic
devices is possible for future Erbium-based lasing in silicon
photonics regarding the current propagation losses of silicon
waveguides.

Songtao Li, North China Electric Power Univ. (China); Li
Wang, Tianrui Thai, Xiaofeng Wu, Fei Tong, Xinping Zhang,
Beijing Univ. of Technology (China)

Here, we report our recent progress regarding the integration
Er3+ doped materials in silicon and silicon nitride slot
waveguides/devices. Two kinds of Er3+ material: Erbium
doped polymers and Er2O3/Al2O3 atomic layer, integrations insilicon and silicon nitride has been studied, which includes the
optimization of waveguide losses, PL properties of the Erbium
materials and hybrid integration methods. The light propagationand gain measurements before and after Erbium integration with
our slotted photonic devices prove good potentials for high net
gain amplifiers in future hybrid silicon and silicon nitride photonic
circuits.

The random lasers attract worldwide attentions for the merits,

1. X. Wang, X. Zhuang, S. Yang, Y. Chen, Q. Zhang, X. Zhu, H.
Zhou, P. Guo, J. Liang, Y. Huang, A. Pan, and X. Duan, “High

10027-8, Session 2

Studies on the amplified spontaneousemission of a polymer fiber

204

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Conference 10027:
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Gain Submicrometer Optical Amplifier at Near-Infrared
Communication Band,” Phys. Rev. Lett. 115, 1–6 (2015).
2. F. Pyatkov, V. Fütterling, S. Khasminskaya, B. S. Flavel, R.
Krupke, and W. H. Pernice, “Cavity enhanced light emission fromelectrically driven carbon nanotubes,” Nat. Photonics 1–9 (2016).

10027-10, Session 2n-type reverse-rib germanium laser
structures doped by phosphorus diffusion
process
Chan-Hyuck Park, Kookmin Univ. (Korea, Republic of);
Motoki Yako, Yasuhiko Ishikawa, The Univ. of Tokyo(Japan); Kazumi Wada, Massachusetts Institute ofTechnology (United States); Donghwan Ahn, Kookmin
Univ. (Korea, Republic of)Germanium (Ge) is a promising gain medium for monolithic
integrated laser on silicon platform. In this paper, we reportlight emission from a reverse-rib Ge cavity structures that weremade using P diffusion to an epitaxial lateral overgrowth (ELO)
layer. Such structures enabled concentrating greater portion of
the optical mode to be positioned in the Ge gain medium. In
contrast to the ion implantations that may induce irreversible
Ge lattice damage to prevent emission of Ge, we employed P
diffusion method, which achieved 1?1019 /cm3 in the reverse-rib
Ge structures. We achieved 10 times enhancement of PL intensity
compared with undoped Ge. Developing such ex-situ diffusion
process instead of using in-situ doping method during the Ge
epitaxy also means that one can achieve different doping profiles
tailored for different types of Ge photonic devices such as laser(LD), photodetectors (PD), and modulators (MOD) integrated in
one chip even after one unified one intrinsic Ge epitaxy, which
is more realistic than performing multiple epitaxies for manydifferent types of Ge devices.

10027-11, Session 3

Optical waveguide materials, structure,and dispersion modulation (Invited Paper)lens based SPM is often limited by the optical field profile oflight probe incident on the pupil of objective lens which may
has distorted pupil, finite aperture stop, etc. Here we assume
the undistorted pupil and only consider how the finite aperture
stop distorts the emission and affects the performance of SPRM.
Physically, finite aperture of a physical objective lens refers
to sudden transition on the clear aperture edge and limited
bandwidth of the system. Here we give a simplified model ofthe SPM and numerically calculate how the sudden transitionon the clear aperture edge causes inherent error. A spatial light
modulator will be applied to modulate the illumination beamprofile and suppress the inherent error.

10027-13, Session 3

Hybrid WGM-SPP modes in metal-coatedmicrocylinder
Yadong Miao, Zhuo Zhang, Mi Li, Yu Xiang, YunchongPeng, Qiang Chen, Yuejiang Song, Nanjing Univ. (China)
It is well known that surface plasmon polariton (SPP) has
potential application in biochemical sensing but with a limit of
low quality factor. In the paper, we study the mode characteristics
and sensing characteristics of metal-coated cylindricalmicrocavity with Mie theory. According to its eigenequation,mode characteristics, including the field distribution, dispersion
curve, and Q factor of silver coated microcylinder, can beachieved by the analytic method. The mode index of SPPs mode
decreases with the increase of the microcylinder radius, whileother mode increases with radius. Due to the extraordinarymode index of SPPs mode, it can couple with other TM modes
when they have approximate mode index. The generated hybrid
TM-SPPs modes (or supermodes) have both high Q factor andhigh surface enhancement factor, which is different from thetraditional SPP mode and dielectric whispering gallery mode
(WGM).
Also the sensitivity and the figure of merit (FoM) of the hybrid
modes are studied. The hybrid TM-SPPs modes have highsensitivity (~260 nm/RIU), more than one order of magnitude
higher than traditional WGM modes in dielectric microcavity, andhigh FoM (~1100), higher than traditional SPP mode. These hybrid
modes can be widely used in many applications due to both its
high Q factor and high refractive sensitivity.

Zhisong Xiao, BeiHang Univ. (China)
No Abstract Available

10027-14, Session 310027-12, Session 3

Manipulating the effective index of thehybrid plasmonic waveguide based on
subwavelength grating

Inherent error in interferometric surface
plasmon microscopy
Bei Zhang, BeiHang Univ. (China) and Univ. of Nottingham(United Kingdom); Peng Yan, Feng Gao, BeiHang Univ.
(China); Le Wang, Renmin Univ. of China (China)
Surface plasmon microscopy (SPM) is a kind of surface plasmons
optical system which employs high refractive index prismor high numerical aperture (NA) objective lens as coupling
agent to excite surface plasmon considering the conservationof momentum of k vector in SPs. Here we apply high NA oilimmersion objective lens considering k vector conditions of SPs
and localization of SPs which provides better lateral resolution
and less cross-table between adjacent areas. Fundamentally,
image contrast or sensing sensitivity of a SPM arises fromsurface plasmon wave coupling and specific specimen-chemicalinteraction, however, the optimum resolution, contrast or
sensitivity can be achieved only if the illumination profile is of theappropriate form. That means the performance of an objective

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Rui Zhang, Bowen Bai, Zhiping Zhou, Peking Univ (China)
The properties of grating based hybrid plasmonic waveguideis first investigated in this paper. Due to the existence of metal
layer on top of the grating, this structure exhibits unique featurescompared with conventional silicon based waveguide. Three main
factors influence effective index of the waveguide, which are
grating period, duty cycle and width, respectively. By controlling
duty cycle and grating period, the function which maps effective
index variable to waveguide width can be changed. It is worth
noting that the function might be concave function or convex
function, which is different from the traditional hybrid plasmonic
waveguide. Moreover, at certain duty cycle and grating period,
the slope of the function is similar to TM mode of silicon
based waveguide, which is of great potential for SPPs based
applications.

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Conference 10027:
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10027-15, Session 4(Russian Federation)

Ultrahigh-Q asymmetric microcavity
photonics (Invited Paper)

Fluid systems containing nanocarbon particles have a plethora
of applications, nonlinear optical power limiting (OPL) andphotodynamic therapy being among them. We’ve focused on
two types of systems: suspensions of fullerenes and dispersionsof single-walled carbon nanotubes (SWCNT). We’ve studied
correlations between the stability of SWCNT suspensions,stabilized by various amphiphiles, and aggregative properties of
the used stabilizers in mixed media. Non-linear optical behavior
of all the suspensions was checked. Further, the correlation
between stability of the aggregated suspensions of fullerenes
and their photo-dynamic properties was investigated.

Yun-Feng Xiao, Peking Univ. (China)
No Abstract Available

10027-16, Session 4

Enhanced CNT photoluminescence in
integrated silicon photonic resonators

The results show principal viability of nonlinear optical filtersand singlet-oxygen generators on the platform of variously
aggregated carbon nanoparticles for application in eyeprotective optical devices, oxygen therapy of pathogens andenvironmentally compatible oxygen-iodine lasers.

Weiwei Zhang, Elena Durán-Valdeiglesias, Samuel Serna,
Thi-Hong-Cam Hoang, Carlos Alonso-Ramos, Xavier
Le Roux, Univ. Paris-Sud 11 (France); Arianna Filoramo,Commissariat à l’Énergie Atomique (France); Francesco
Sarti, Ughetta Torrini, Univ. degli Studi di Firenze(Italy); Hongliu Yang, Gianaurelio Cuniberti, TU Dresden(Germany); Massimo Gurioli, Univ. degli Studi di Firenze(Italy); Viktor Bezugly, TU Dresden (Germany); Eric
Cassan, Laurent Vivien, Univ. Paris-Sud 11 (France)

10027-18, Session 4

High-performance one-way transmission
using pyramid-shaped silicon gratingcoupled hyperbolic metamaterial

The on-chip integration of all electronic, photonic, optoelectronic,
memory blocks on the silicon platform is the ultimate goal of
future processors. A further step of perusing high efficiency
and low energy consuming, device miniaturization in the chipis restricted by the CMOS compatible materials themselves.
New materials like carbon nanotubes (CNTs) and graphene
have been recently reported as key materials both in electronics
and optoelectronics for the realization of nano devices such as
electronic new transistors, as well as light emitting, modulating
and detecting devices [1].
We propose here to integrate high concentration selected
semiconductor CNTs into silicon photonic structures to improve
the hybrid properties of silicon-compatible silicon devices. CNTs
have indeed the ability to emit, modulate and detect light in thetelecommunication wavelength range.
We report the study of the light emission from CNTs coupled
into optical resonators/nanocavities implemented on the siliconon-insulator (SOI) platform. A theoretical and experimental
analysis of the light interaction of CNTs with micro-ringresonators based on strip/slot waveguides, slot photonic crystal
heterostructure cavities and air mode nanobeam cavities has
been carried out. Enhanced photoluminescence (PL) into two
types of ring resonators: strip ring resonators and slot ring
resonators, have been measured and polarization sensitivity has
been demonstrated also. The PL collected through coupled bus
waveguides shows 20dB signal extinction ratio. Additionally,
Purcell effects have been investigated in different types of highQ slotted photonic cavities and air mode nanobeam cavities, a
crucial step towards a CNT-laser.
1. P. Avouris, M. Freitag, and V. Perebeinos, “Carbon-nanotube
photonics and optoelectronics,” Nat. Photonics 2, 341–350(2008).

Stability and non-linear optical propertiesof nanocarbon dispersions
Anastasia V. Venediktova, Andrey Y. Vlasov, SaintPetersburg State Univ. (Russian Federation); Ivan M.
Kislyakov, ITMO Univ. (Russian Federation); Vladimir Y.
Venediktov, Saint Petersburg Electrotechnical Univ. “LETI”(Russian Federation) and Saint Petersburg State Univ.

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An asymmetric transmission device has been demonstrated torealize high-contrast one-way pass transmission for incident
visible plane wave. Non-symmetric pyramid-shaped silicongratings and narrow band metal/dielectric multilayer structure
were incorporated to display the one-way transmission with highperformance with contrast ratio exceeding 20dB. Simulation
results demonstrate pyramid-shaped silicon gratings will greatly
enhance the coupling and decoupling efficiency between the
propagating wave in free space and the coupling plasmon modes
supported by the metal/dielectric multilayer. The improved theone-way transmission performance offered by pyramid-shaped
silicon grating coupling may hold great potential in many
applications such as super-resolution plasmonic lithography,
isolator and polarizer for super-compact photonic integrated
circuit.

10027-37, Session Post

Wavelength conversion enhancement byusing electric dipole and magnetic dipole
resonance of nanocylinder
Kihwan Moon, Young Jin Lee, Seokhyeon Hong, SoonHong Kwon, Chung-Ang Univ. (Korea, Republic of)10027-17, Session 4

206

Jigang Hu Sr., Yeming Qing, Zhenqiang Wen, Xiaohang
Wu, Hefei Univ. of Technology (China); Yongze Ren, Hefei
Univ of Technology (China); Weiqing Gao, Hefei Univ. ofTechnology (China); Dongmei Li, Hefei Univ of Technology(China); Feng Gao, Hefei Univ. of Technology (China)

Upconversion (UC) materials, which absorbs near-infrared (NIR)
light and emits visible light, are promising to harvest visual light.
However UC process efficiency is very low to apply for device.
Therefore, we propose nanocylinder-shaped structure into UC
material, inducing electric dipole (ED) and magnetic dipole(MD) resonances, to increase efficiency of UC process. The
nanocylinder is not only able to increase the light absorption
but also tailor scattering direction of induced light by Mie
resonance, called ED and MD. Resonant wavelength of ED andMD can be tuned by controlling the parameter of nanocylinder,height and diameter. When the absorption wavelength, NIR
light, of UC material is matched to MD resonance, interaction
between the nanocylinder and incident light is enhanced

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Conference 10027:
Nanophotonics and Micro/Nano Optics III
owing to MD resonance. In order to achieve uni-directionalemission of visible light, we introduce gold substrate below UC
nanocylinders as a reflector. We investigate the amount of usefulvisible light emission, which is emitted into vertical direction
from UC nanostructure. For comparison of UC process per unit
volume, the reference structure consisting of UC layer and gold
substrate is set to same to volume of UC nanocylinder. The
vertically emitted light is strongly enhanced by ED resonances. In
summary, we obtained absorption enhancement of 7.3 times andvertical directional emission enhancement of 155 times in finitedifferential time domain (FDTD).

10027-38, Session Post

Silver nanoparticles plasmonic effect on
eosin and rhodamine 6G luminescence invarious media
Ilia Samusev, Immanuel Kant Baltic Federal Univ. (RussianFederation); Anna Tsibulnikova, Immanuel Kant Baltic
Federal Univ. (Russian Federation) and Kaliningrad
State Technical Univ. (Russian Federation); Nadezhda
Tikhomirova, Immanuel Kant Baltic Federal Univ. (RussianFederation) and Kaliningrad State Technical Univ. (RussianFederation); Vasiliy Slezhkin, Immanuel Kant Baltic Federal
Univ. (Russian Federation) and Kaliningrad State Technical
Univ. (Russian Federation); Valery Bryukhanov, Andrey
Zyubin, Immanuel Kant Baltic Federal Univ. (RussianFederation)
The plasmonic enhancement and quenching of phosphorescenceand fluorescence of the anionic (eosin) and cationic (rhodamine
6G) dyes have been studied in various environments: silver
nanoparticles of silver hydrosol citrate in water, in polymer films
and on the surface of nanoporous silica in order to determine thekinetic and spectral effects on the dye luminescence. Dependingon the silver nanoparticles concentration both the enhancement
and quenching of the dyes phosphorescence and fluorescencehave been detected. The mechanism of interaction between the
excited molecules and silver nanoparticles has been discussed. In
this paper we aimed to perform comparative study of the silver
nanoparticles effect of the average size of 35 nm in the silverhydrosol citrate on the fluorescence of the anionic and cationicdyes in various environments: in water, in polymer films andon the surface of nanoporous silica. Comparative study of therole of the total charge of the dye seams quite important in theelucidation of the interaction mechanism between the dye andthe surface plasmonic resonance. The research has been carriedout within the state assignment of the Ministry of Education andScience of Russian Federation (project No. 3.809.2014/?).

10027-39, Session Post

Luminescence quantum yields of gold
nanoparticles varying with excitation
wavelengths
Yuqing Cheng, Guowei Lu, Peking Univ. (China)
Luminescence quantum yields (QYs) of gold nanoparticles
including nanorods, nanobipyramids and nanospheres aremeasured elaborately at a single nanoparticle level withdifferent excitation wavelengths. It is found that the QYs of
the nanostructures are essentially dependent on the excitation
wavelength. The QY is higher when the excitation wavelength isblue-detuned and close to the nanoparticles’ surface plasmon
resonance peak. A phenomenological model based on theplasmonic resonator concept is proposed to understand theexperimental findings. The excitation wavelength dependent QY

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is attributed to the wavelength dependent coupling efficiency
between the free electron oscillation and the intrinsic plasmon
resonant radiative mode. These studies should contribute to
the understanding of one-photon luminescence from metallic
nanostructures and plasmonic surface enhanced spectroscopy.

10027-40, Session Post

Optical resolution improvement by
nanoparticle’s amplitude and phasepattern
Xin Hong, Xiaoyaun Sun, Dalian Univ. of Technology(China)Optical detection of nanoparticle with ultra-high sensitivity plays
an important role in bio- / nano- and their relative research fields.
However, it is a rather hard task to detect a single nanometer
sized non-luminescent particle directly by optical method due
to its very small cross section. By using highly focused Gaussianbeam, we recently developed a method which can detect asingle nanoparticle by producing both amplitude and phase
images. Each particle exhibits unique 4-lobes pattern both in
the amplitude and phase distribution respectively, which open
a window to explored the possibility of resolution improvement
by a particle pair. When two particles are attaching each other,
the total field resulted from their interaction will be changed. In
consequence it will lead to the scattering amplitude and phase
distribution pattern changes. Based on which, a particle pair
was employ to test the resolution. In this paper two polystyrene
beads at the diameter of 100nm were employed with the gap
distance ranging from 100-400nm. The amplitude and phase
distribution of the particle pair were simulated by FDTD solver.
The simulation results show that the images are sensitive tothe geometrical parameters of the two particles, such as gap
distance and direction and the calculation result suggests a
resolution of 100nm.

10027-41, Session Post

Tunable optical properties of the coreshell nanoparticles
Xin Hong, Chencheng Wang, Dalian Univ. of Technology(China)Noble metallic nanoparticle exhibits unique optical properties invisible to near infrared band when its localized surface plasmon
resonance (LSPR) is excited. This is because when the incident
photon frequency in consistent with the collective oscillationof metal nanoparticles internal free electrons frequency, thenanoparticle producing resonance absorption or resonancescattering, at the same time the electric field intensity near
the surface of the nanoparticles getting greatly enhanced .
For example, a sharp absorption peak is at 525nm for a gold
nanoparticle at the diameter of 60nm. The strong dependenceof plasmonic properties on its geometrical structure makes themmore attractive to obtain artificially tunable properties. In thebiomedical applications, a broad band adjustment is expected
in order to obtain an optimum measurement window. Thisrequirement needs a selected nanostructure design in advance ofsynthesis. In this paper, we theoretically get the optical properties
by calculating its cross sections of scattering, absorption andextinction of a single solid nanoparticle. However, the peak
position makes rather low change. Keep it as a reference, we
explored in detail a core-shell structure, whose structure wascomposed of dielectric core and a gold shell. The simulation
results show that the core-shell structure can reach a muchbroader tunable band and the shell thickness plays a dominantrole. Further by employing a core-shell pair, more flexible
properties can be reached.

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Conference 10027:
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10027-42, Session Post

10027-44, Session Post

Angular sensitivity for a Fabry-Perotstructure incorporating different dielectricmaterials

Near-infrared absorptance enhancementand device application of nanostructured
black silicon fabricated by metal-assist
chemical etching

Shangliang Wu, Yan Ye, Yun Zhou, Wenbin Huang, Yanhua
Liu, Soochow Univ. (China); Wen Qiao, Soochow Univ.
(China) and Soochow University (China); Yanyan Wang,
Minghui Luo, Linsen Chen, Soochow Univ. (China)
Color filters based on different Fabry-Perot structures areinvestigated extensively, and incident angle dependency is
an important characteristic in practical applications. Here,
we investigated a color filter incorporating a Fabry-Perotstructure, discussing its reflective angular sensitivity related torefractive index of its dielectric material. By finite differencetime domain(FDTD) theory, the refractive index of the dielectricmaterial is found to influence the angular sensitivity greatly
while the optical thickness keeps constant. The simulated resultsshows that the higher the dielectric layer’s refractive index is, themore angular insensitive of the reflection will be obtained and agood angular insensitive will achieved when the refractive index
is larger than 2. Finally, samples with different dielectric layer
are fabricated in experiment and the measured results verify
influence of the refractive index of dielectric layer on the spectraangular sensitivity, which is helpful for the application of color
filter in color display, image sensors and decoration.

10027-43, Session Post

Improvement of metal-semiconductor
contact on silicon microstructured surface
by electroless nickel technique
Fei Long, Chongqing Acoustic-Optic-Electronic Co.,
Ltd. (China); Anran Guo, Univ. of Electronic Science andTechnology of China (China); Lieyun Huang, Chongqing
Acoustic-Optic-Electronic Co., Ltd. (China); Feng Yu, Wei
Li, Univ. of Electronic Science and Technology of China(China)Si micro-structures served as anti-reflection layer are widely
employed in Si-based solar cells and detectors to enhance lightharvesting. However, performance of these devices is sufferedfrom the poor contact between the metal electrode and microstructured surface. Conventional vacuum deposited metalelectrode makes only superficial contact with the top of microstructured surface and unable to fill the pores in the microstructures. In this paper, instead, electroless nickel technique
is applied to form low resistance ohmic contact. The surface
micro-structures were fabricated by electrochemistry etching
while the metal electrodes were deposited by several approaches
including thermal evaporation, sputtering and electroless.
Specifically, two different electroless nickel processes (acidity or
alkalinity) were carried out and their effects were compared. The
morphology of micro-structured surface and covered metal layer
was presented by SEM, and the electrical contacts between themwere measured by Keithley4200 semiconductor characterization
system. Results show that only electroless nickel layer could
fully fill the pores and achieve good ohmic contact before rapid
annealing. Furthermore, a higher temperature rapid annealing
process could improve the contact of all samples prepared bydifferent ways. The lowest specific contact resistance achieved byalkalinity electroless nickel is 1.34?10-1?•cm2.

208

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Lieyun Huang, No. 44 Research Institute of China
Electronics Technology Group Corp. (China) andChongqing Acoustic-Optic-Electronic Co., Ltd. (China);
Hao Zhong, Univ. of Electronic Science and Technology
of China (China); Naiman Liao, No.44 Research Institute,
Chongqing Acoustic-Optic-Electronic CO., LTD, CETC
(China); Fei Long, No. 44 Research Institute of China
Electronics Technology Group Corp. (China) andChongqing Acoustic-Optic-Electronic Co., Ltd. (China);
Guohui Guo, Wei Li, Univ. of Electronic Science andTechnology of China (China)
We use metal-assist chemical etching (MCE) method to fabricate
nanostructured black silicon on the surface of C-Si. In our MCE
process, a chemical reduction reaction of silver cation (Ag+) will
happen on the surface of silicon substrate, and at the same time
the silicon atoms around Ag particles are oxidized and dissolved,
generating nanopores and finally forming a layer called blacksilicon on the top of the substrates. The nanopores have diameterand length of about 400 nm and 2 ?m, respectively. Furthermore,these modified surfaces show higher light absorptance in nearinfrared range (800 to 2500 nm) compared to that of C-Si with
polished surfaces, and the maximum light absorptance increases
significantly up to 95% in the wavelength region of 400 to 2500
nm. The Si-PIN photoelectronic detector based on this type of
black silicon, in which the black silicon layer is directly set as thephotosensitive surface, has a substantial increase in responsivity
with about 80 nm red shift of peak responsivity, particularly at
near-infrared wavelengths, rising to 0.57 A/W at 1060 nm and0.37 A/W at 1100 nm, respectively. Our recent novel results
clearly indicate that nanostructured black silicon made by MCE
has a potential application in near-infrared photoelectronic
detectors.

10027-45, Session Post

Model of blocking dislocations for III-V
semiconductor grown on nano-trenchpatterned Si substrates
Haoyuan Ma, Jun Wang, Zhuo Cheng, Yibing Fan, Ran
Zhang, Beijing Univ. of Posts and Telecommunications(China); Yuanyuan Liu, Institute of Semiconductors(China); Yongqing Huang, Xiao-Min Ren, Beijing Univ. ofPosts and Telecommunications (China)
In epitaxial lateral overgrowth (ELOG) of III-V semiconductorgrown on nano-trench patterned Si substrates, the mostimportant mechanism is aspect ratio trapping, which uses highaspect ratio nano-trenches to trap threading dislocations. A
model based on the theory of dislocation is proposed to calculate
proportion of blocking threading dislocations in ELOG of GaAs
or InP on nano-trench patterned Si substrates. The model
establishes relationship with the structure of nano-trenches andthe proportion of blocking threading dislocations. It is found that,the proportion is determined by thickness of the masks, widthof the trenches and direction of the nano-trenches (the angle ofopening orientations lies off the [110] direction). The proportion
gradually increases until 100% as aspect ratio increases with
fixed trench direction; With the same aspect ratio, the proportion
firstly decreases from 0°to 45°, and symmetrically increases fromwww.spie.org/pa·

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Conference 10027:
Nanophotonics and Micro/Nano Optics III
45°to 90°. It is worth noting that the proportion abruptly reduces
to 50% when the direction is 45°and the aspect ratio is morethan 1; But it does not happen if the aspect ratio is less than orequal to 1. The reported experimental results are well consistent
with the model. The model provides a method for optimization of
nano-trench patterned substrates for more effectively blocking
threading dislocations on III-V semiconductor grown on nanotrench patterned Si substrates.

10027-48, Session Post

10027-46, Session Post

Single photon sources are key devices for quantum
communication and quantum computation. Recently, photonic
nanowires with an embedded quantum dot have demonstrated
to provide remarkable extraction efficiency due to the axial
waveguide configuration and nanocavity function of nanowire.
However, for thin nanowires, stable modes cannot be supported,
resulting in very poor Purcell factor which is an importantparameter of single photon sources.

CdS quantum-dot sensitized solar-cellbased ZnO nanorods grown on a Ti
substrate
Chunyan Zhou, Qian Chen, Xiaoshan Zhang, Fangfang
Gao, Jiehua Xu, Liya Zhou, Guangxi Univ. (China)
Comparatively long zinc oxide (ZnO) nanorods (NRs) was
successfully prepared on a polished Ti substrate by thehydrothermal method. Then the NRs were further sensitizedby 3-mercaptopropionic acid (3-MPA)-capped CdS quantum
dots (QDs) with a cubic structure and excellent crystallinity as aphotoanode of QD-sensitized solar cells (QDSSCs) via the direct
adsorption (DA) technique. The effect of sensitization time of
CdS QDs on performance of the QDSSCs was systematicallyinvestigated. The absorption band of sensitized NRs redshifted and broadened to the visible spectrum, thereby improvelight-harvesting efficiency of the photoelectrode. For the CdS
QD-sensitized ZnO NRs polished Ti substrate, the conversion
efficiency can reach a maximum of 0.702%, which was enhanced
by 350% compared with that of the cell based on CdS QDsensitized ZnO NRs (0.201%).

10027-47, Session Post

Photoelectrochemical performanceresearch of CdTe:Eu3+ quantum-dotsensitized TiO2 nanotube array solar cells

Purcell enhancement of emitting fromthe quantum-dot-in-nanowire structure
surrounded by Au
Fengling Tang, Xin Yan, Xia Zhang, Xiao-Min Ren, Beijing
Univ. of Posts and Telecommunications (China)

In this paper, a novel single photon source structure with ahigh Purcell factor is proposed and simulated. The structure
consists of a GaAs nanowire embedded with an InAs quantum
dot surrounded by Au. The enhancement of the Purcell factor
is simulated by finite difference time domain (FDTD) method.
Without Au shell, the Purcell factor quickly drops as the diameterof nanowire decreases. When the diameter is decreased to 50
nm, the nanowire cannot support any stable modes, resulting
in a rather low Purcell factor of 0.009. After the Au shell is
introduced, the Purcell factor is dramatically enhanced, and theenhancement ratio increases as the nanowire diameter decreases.
The highest enhancement ratio of 1028 can be obtained at a
nanowire diameter of 50 nm and Au shell thickness of 75 nm. The
enhancement of the Purcell factor is attributed to the decrease of
the cavity effective mode volume, which is inversely proportion
to the Purcell factor. This work may offer a way to achieve single
photon sources with an ultrasmall size and ultrahigh Purcell
factor.

10027-50, Session Post

Optical switching of scattering direction insilicon-gold dimer

Qian Chen, Chunyan Zhou, Fangfang Gao, Xiaoshan
Zhang, Liya Zhou, Guangxi Univ. (China)

Bona Ku, Young Jin Lee, Seokhyeon Hong, Kihwan Moon,
Soon-Hong Kwon, Chung-Ang Univ. (Korea, Republic of)Quantum dots (QDs) sensitized solar cells (QDSSCs) basedon TiO2 nanotube arrays (TNTAs) have attracted considerable
interest because of their outstanding sunlight conversion
efficiency. To decrease the band-gap of TNTAs and widen theabsorption spectra to the visible region, doped-QDs have been
modified in the surface of TNTAs. In this paper, CdTe: Eu3+/
TNTAs prepared by using a novel one-step synthesis process with
Thioglycolic acid (TGA) as stabilizer. X-ray powder diffraction
and high-resolution transmission electron microscopy analyses
confirmed that the obtained CdTe: Eu3+ quantum dots (QDs)possess cubic structures. The influences of sensitization timeand Eu3+ ion concentrations are investigated systematically.
The photocurrent of the CdTe: Eu3+ QDs/ TNTAs appear at themain absorption region of 300–510 nm. Compared with thatof the TNTAs and CdTe/TNTAs, the photoelectric conversion
efficiency of CdTe:3% Eu3+/TNTAs (0.29%) increased apparently.
This scenario exhibits the potential applications of QDs inphotochemical solar cells.

Resonant scattering of nanodimer composed of silicon (Si)and gold (Au) enables controlling of scattering direction
depending on the wavelength of incident light. Silicon has two
representative resonances based on Mie resonance, called
electric dipole (ED) and magnetic dipole (MD). But, gold shows
dipole like resonance for incident light. because of its plasmonicresonance phenomenon. We make a dimer structure consistingof Si and Au spheres which are separated by airgap of 20 nm.
In this study, the direction of forward scattering in proposed
dimer is tuned by changing the wavelength of incident light. In
dimer, Si and Au spheres have 100 nm and 130 nm diameters,
respectively. We simulate scattering cross-section and the farfield of scattering light in the dimer as the wavelength changes
from the ED wavelength (610 nm) to MD wavelength (770 nm)
of Si nanosphere. In contrast to strong forward scattering withsame direction of incident light in the single nanosphere, thescattering in the hybrid dimer shows deflection of incident lightdepending on the wavelength. The maximum angle of forward
scattering is shifted 15° when the wavelength of incident wave ischanged from 610 nm to 770 nm. The scattering angle at certain
wavelength can be controlled by changing sphere structures andgap spacing in dimer.

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Conference 10027:
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10027-51, Session Post

10027-53, Session Post

Optimized design of metal-coated opticalfiber tips with embedded plasmonicslot nano-resonators for maximum fieldenhancement

Optical reflection efficiency modulation
based on graphene film

Afroditi Petropoulou, National Hellenic Research
Foundation (Greece) and Univ. of Peloponnese (Greece);
Michalis N. Zervas, Optoelectronics Research Ctr. (United
Kingdom); Christos Riziotis, National Hellenic Research
Foundation (Greece)
Plasmonic Nano-Resonators (PNRs) are subwavelengthsized metallic apertures that offer high field confinement andenhancement. Their integration to optical fibers tips with thinmetallic claddings forms plasmonic slot nano-resonators (PSNRs)
providing ease of light coupling from the fiber’s core modes tothe slot. It is demonstrated here that the placement of the PSNR
at the cut-off radius of the fiber tip where the group velocity
tends to zero and light slows down leads to the optimization offield’s enhancement. Finite Element Method (FEM) simulations
were performed for the calculation of the cut-off radius and of
the intensity enhancement factors (Ef) of PSNR’s embedded inmetal-coated fiber tips at different radii. A number of different
fiber tips with different geometrical characteristics were also
tested and studied in order to identify optimal conditions for loss
minimization. Maximum intensity enhancement of PSNR’s placedat different radii shows a linear dependence between excitation
wavelength and radius, making it feasible to select the proper
radius for a specific wavelength for maximum enhancement. The
designed plasmonic system provides Ef greater than 5x10^5 andcan find many practical applications in nano-optics and sensing.

10027-52, Session Post

Study of waveguide directly writing in
LiNbO3 crystal by high-repetition-rate
femtosecond laser
Chuan Wu, Feng Jie, Southwest Univ. of Science andTechnology (China); Yongjia Yang, Southwest Universityof Science and Technology (China); Jiangui Mao, Anlin
Luo, Southwest Univ. of Science and Technology (China);
Zigang Zhou, Southwest University of Science andTechnology (China)
In this paper, we demonstrate the buried waveguides directly
writing in LiNbO3 crystal by a tightly focused femtosecond laser
with repetition rate 75MHz, and the femtosecond laser is focusedby the microscope objective of which NA is 0.65. Fabricatingnine carved paths in LiNbO3 crystal by moving three-dimensional
electric translation stage at different speeds varying from 2mm/s
to 10mm/s, controlled by a computer. Analyzing the structure of
the end face of the directly writing region by laser Raman, whichshows the large-scale defects are generated in the center of theetching region, densification induced by the thermal effect ofhigh repetition rate femtosecond laser interaction of LiNbO3 are
generated below and down of the center of the etching region.
Using a He-Ne laser focused by a microscope objective with NA
0.65 coupling to the end face of the prefabricated nine carved
paths, which shows two waveguides are generated in the top
and below of the inscribing region. Testing the insert loses ofthese waveguides with an optical power meter, the result showsthat the insert loses of the waveguides fabricated at speed of
8~10mm/s is low to 3dB·cm-1, and the insert loses is low to 1.5
dB·cm-1 when the scanning speed is 9mm/s, moreover, the insert
loses of the below region is low to the top region.

210

SPIE Photonics Asia·

Junbo Yang, Jie Huang, Wenjun Wu, Dingbo Chen,
Jingjing Zhang, National Univ. of Defense Technology(China)This paper presents a comprehensive study of light reflection
modulation in graphene through external applied voltage andshows a strategy to realize both broadband and strong reflection
enhancement. The influence of chemical potential, applied
voltage and carrier concentration on reflection efficiency are
investigated by numerical simulations. By employing an applied
voltage, the maximum of difference of reflected coefficient canreach up to 30% for 3THz radian frequency. Thus, using external
voltage to control optical reflection efficiency is testified to bereasonable and feasible based on graphene film. Furthermore, thereflection efficiency modulation can be realized at a wideband of
frequency.

10027-54, Session Post

Enhanced absorption in graphenemonolayer with guided mode resonance
Jun Wu, Hongchao Cao, Shanghai Institute of Optics andFine Mechanics (China)
The complete absorption in graphene monolayer throughthe critical coupling effect is investigated. It is achieved bysandwiching the graphene monolayer between a dielectric
grating and a Bragg grating. The optimized structure parameterswith the operating wavelength at about 1550 nm are obtained byuse of the rigorous coupled-wave analysis (RCWA). The designed
graphene absorber exhibits near-unity absorption at resonance,
which is attributed to the combined effects of guided mode
resonance with dielectric grating and the photonic band gap
with Bragg grating. Moreover, the designed graphene absorberhas perfect absorption/emission with highly directional and acts
similar to an antenna. In contrast to the numerical simulation,a coupled-mode theory model is also presented to verify thecorrectness of the numerical result. Furthermore, the electric field
distributions are illustrated to provide a physical understandingof the perfect absorption effect. It is believed that the method
proposed here may benefit the design of novel graphene-based
optoelectronic devices, such as photodetector, modulator andabsorber/thermal emitter.

10027-19, Session 5

Defect-free fabrication of nano-disk andnano-wire by fusion of bio-template andneutral beam etching (Invited Paper)
Seiji Samukawa, Shuichi Noda, Tohoku Univ. (Japan);
Manabu Yasuda, Kazumi Wada, The Univ. of Tokyo (Japan)
It has been suggested that by 2020, Moore’s Law will break
down and we will reach the physical limits of transistor operation.
Work is therefore under way in several countries to develop
nano-devices based on new principles using quantum effects. To
fabricate quantum effect devices, it is essential that defect-freenanostructures (dots and wires) can be formed with precision
down to the atomic layer level. For this purpose, we proposed
and are researching the formation of quantum nanodots andnano-wires of less than 10 nm in size by means of a top-down
process using a low-energy neutral beam capable of defectfree processing. An advantage of the top-down process is thatwww.spie.org/pa·

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Conference 10027:
Nanophotonics and Micro/Nano Optics III
it can form nanostructures with an arrangement that can be
uniformly controlled no matter what combination of materials
is used. Instead of photolithography, we used a bio-template asan etching mask with dots of a few nm in size. By combinationof bio-template and defect-free neutral beam etching, the sub10-nm quantum nano-dots (discs) and –wire (-columns) for
any materials such as Si, Ge, GaAs, InGaAs and InGaN could be
fabricated in an array configuration with uniform spacing. It canbe seen that the bandgap can be controlled over a wide range
with high precision by varying the nano-disc (column) size andmaterial. No other quantum dot fabrication techniques canoffer this kind of flexible and precise bandgap control. We are
currently developing high efficiency quantum dot energy/opticaldevices (Solar Cells, Laser/LED).

10027-20, Session 5

1?5 optical splitter for TE modes in airhole photonic crystal based on selfcollimation effectWeijuan Chen, Yuanyuan Lin, Fujian Normal Univ. (China);
Guimin Lin, Ping Fu, Minjiang Univ. (China); Chengkun Liu,
Junzhen Jiang, Yishen Qiu, Hui Li, Fujian Normal Univ.
(China); Xiyao Chen, Minjiang Univ. (China)
We propose a novel 1?5 optical splitter (OS) for TE modes basedon self-collimation effect in an air-hole type 2D silicon photonic
crystal. The OS consists of two cascaded resonators which
is formed by eight beam splitters. We obtain the theoreticaltransmission spectra of OS by using multiple-beam interference
theory. With our analysis of transmission spectra, we find that thetransmission spectra at five drop ports will reach the maximum
values while the transmission spectra at two through ports reachzero for resonant frequencies. By scanning the radius of a beam
splitter, the relationship between the radius and the reflectivity is
obtained. Therefore, by changing the radii of the air-hole in eightbeam splitters, we can manipulate the output light-intensity ratio
at five drop ports to meet requirement.
Theoretically, when R1=2/11, R2=8/11, R3=5/8, R4=2/5, R5=7/12,
R6 =6/7, R7=1/2, R8 =2/3 ,(Ri is reflectivity of beam splitters),
the light intensity ratio at five drop ports is 1:1:1:1:1. When R1=2/7?R2=6/7?R3=1/2?R4=2/3?R5=1/7,R6=6/7 ,R7=2/3 ,R8 =1/4 , thelight intensity ratio at five drop ports is 2:2:1:2:3. By means offinite-difference time-domain (FDTD) simulations, we simulate
the numerical transmission spectra of OS. The simulation results
are consistent with the theoretical results. Considering microprocessing technology of silicon materials is already available,
this OS can be used in the photonic integrated circuits becauseof its small-size, whole-silicon material and low insertion loss.

10027-21, Session 5Gold nano sphere based fiber optic LSPR
probe for biosensing measurement
Lixia Li, Zigeng Liu, Shimeng Chen, Jianye Guang, Wei
Peng, Dalian Univ. of Technology (China)
In this paper, we report on localized surface plasmon resonance(LSPR) studies of gold nano sphere (GNS) immobilized outside
the fiber core. Different immobilization methods were studied
to verify the better performance. The amino silane method andpolyelectrolyte layer by layer (LBL) self-assembly methods
were used to prepare GNS-based fiber LSPR probe respectively.
Different self-assembly layers were respectively studied in thepolyelectrolyte layer by layer self-assembly method (PDDA
monolayer, PDDA/PSS bilayer, PDDA/PSS/PAH three layer and
PDDA/PSS/PAH/PSS/PAH five layer self-assembly methods) to
explore the optimum layer number of the method.

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The refractive index detection experiments were carried out
using the fiber LSPR probe prepared by the above five methods.
Details of the operation steps and the experimental results werecompared and analyzed. The results show that PDDA/PSS/PAH
three layer self-assembly method demonstrates the best LSPR
spectra. The LSPR light intensity changes gradually when varying
the refractive index of sodium chloride solution outside thesensor. Comparing to the amino silane method, polyelectrolyte
layer by layer self-assembly method is time saving, simple
operating and more stable.
Finally, biomolecule specific recognition and detection
experiment were carried out using LSPR fiber probe based on
the three layer self-assembly method. Through this method,
Ribonuclease B can recognise Con A specifically. The LSPR
spectra also have good linear relation with the variation ofconcentration of Con A.

10027-22, Session 5

Steady- and excited-state dynamics of
mixed halide Perovskite films
Mopelola A. Idowu, Federal Univ. of Agriculture (Nigeria);
Theodore Goodson III, Univ. of Michigan (United States)
Lead halide perovskites which are organic-inorganic hybrid
structures, have recently been discovered to be highly efficient
as light absorbers in solar cells [1]. They exhibit broad absorption
below 800 nm and have an absorption coefficient far greaterthan conventional organometallic dyes used in dye sensitizedsolar cells [2,3]. Non-stoichiometric precursor formed mixed
iodide-bromide lead halide perovskites were grown by the interdiffusion method and films with good morphology and varying
bandgaps with sharp optical band edges were obtained. Thesefilms were investigated to probe their excited state dynamics
and emission properties using steady-state and time-resolved
spectroscopic measurements. Steady state fluorescence wasobserved for the perovskite films and they demonstrated
photoluminescence emission of very high intensities which arenecessary for light emitting and photovoltaic applications; thedifferent compositions exhibited considerably different emission
features. The transient absorption experiments also revealed
that the different iodide-bromide compositions exhibited uniquespectral features of the perovskite material relative to the varying
ratios of the halogens present in them [4].
References[1] Zhao, D., Ke, W., Grice, C.R., Cimaroli, A.J., Tan, X., Yang, M.,
Collins, R.W., Zhang, H., Zhu, K., and Yan, Y. “Annealing-freeefficient vacuum-deposited planar perovskite solar cells with
evaporated fullerenes as electron-selective layers” Nano Energy
19, 88–97 (2016).
[2] Burschka, J., Pellet, N., Moon, S.J., Humphry-Baker, R., Gao,P., Nazeeruddin, M.K., and Grätzel, M.,“Sequential deposition asa route to high-performance perovskite-sensitized solar cells.,”Nature 499 (7458),316–319 (2013).
[3] Wang, Q., Shao, Y., Dong, Q., Xiao, Z., Yuan, Y., and Huang, J.,“Large fill-factor bilayer iodine perovskite solar cells fabricatedby a low-temperature solution-process.,” Energy Environ. Sci., 7,2359-2365 (2014).
[4] Idowu, M.A. and Goodson III,T., Manuscript in preparation

10027-23, Session 5Gold nanoparticle-induced diameter
reduction and enhanced Raman shift inself-rolled-up InGaAs/GaAs microtubes
Xiankun Wang, Qi Wang, Zhaoer Chai, Guoming Mao, Hao#PhotonicsAsia

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Conference 10027:
Nanophotonics and Micro/Nano Optics III
Liu, Jia Chen, Bingfei Liu, Xiao-Min Ren, Beijing Univ. ofPosts and Telecommunications (China)
We have grown an epitaxial structure by metal-organic chemical
vapor deposition (MOCVD). From the GaAs (100) substrate,
the sequences are GaAs buffer layer, 50nm AlAs sacrificial layer
and the In0.2Ga0.8As (10 nm)/ GaAs (20 nm) strained bilayers.
Photolithography and etching techniques have been used todesign square patterns which etch to sacrificial layer. Before
selectively etching the AlAs to release the strained bilayers, 2 nm
Au-film was deposited on mesas by Magnetron Sputtering forembed Au nanoparticles (NPs) in tube wall, which was formed by
Rapid thermal annealing (RTA) under the N2 atmosphere at 650
degrees centigrade for 300s. After annealed in high temperature,
Au film formed small islands just as NPs and attach on thesurface closely.

which is desirable for integrated optics circuits and bio-sensing
applications. The produced nanostructures are demonstrated to
be used as SERS substrates and structural color printing.

10027-26, Session 5

The far-field intensity distribution
modulation of the beam cross-section
using specially designed and fabricatednanostructure
Jiannong Chen, Ludong Univ. (China)

Comparing with microtubes without NPs, diameter reduction
from 2.7µm to 2.4µm has been observed for Au-NPs assistantmicrotubes, characterized by the scanning electronic microscopy(SEM). For understand the morphology change in Au-assistantmicrotubes, room temperature (RT) Raman measurements havebeen employed to study the strain effects reflected by the GaAs
longitudinal optical (LO) phonon mode shifts when compared LO
mode of microtubes with as-grown planar. The spectrum showedthat there were about 10 wavenumbers and 2.6 wavenumbers
blue-shifts for Au-assistant and non-Au-assistant structures
respectively. Larger blue shifts induced larger strain change wereobtained for structure with Au NPs compared with structure
without Au, which demonstrate the reason for the diameter
reduction observed by SEM. This investigation on the method of
reducing diameters of rolled-up microtubes need not to change
the component or thickness of strained layers, NPs can be benefit
to SERS.

Obtaining a light beam with arbitrarily desired intensity
distribution is constructive and significant. The nanoslit milledon the nobal metal film deposited on the substrated can only
allow the electric component perpendicular to the slit to transmit.
Based on the transmission-selective property of the nanoslit to
the perpendicular polarization componenet, we designed andfabricated a nanostructure composed of MxM square units ineach of which there is an azimuthally different-rotated nanoslit.
When a linearly polarized beam is vertically directed onto thisnanostructure, a light beam with modulated intensity distribution
in the far-field is obtained. An arbitrary desired intensity
distribution can be demonstrated with correspondingly designed
and fabricated nanostructure. The optical setup for generating
light beam with any intensity distribution can be very simple
and compact. This method of intensity distribution modulation
may be a potentially powerful tool in many fields such as lightinformation processing, surface plasmon polaritons excitation andoptical data recording.

10027-24, Session 510027-27, Session 5

Title to be determined (Invited Paper)

InGaAsP/InP-air-aperture microcavities
for single-photon sources at 1.55-um
telecommunication band

Bumki Min, KAIST (Korea, Republic of)
No Abstract Available

Sijie Guo, Yanzhen Zheng, Zhuo Weng, Haicheng Yao,
Yuhao Ju, Lei Zhang, Zhilei Ren, Ruoyao Gao, Zhiming
M. Wang, Univ. of Electronic Science and Technology ofChina (China); Hai-Zhi Song, Univ. of Electronic Scienceand Technology of China (China) and Southwest Instituteof Technical Physics (China)

10027-25, Session 5

Fabrication of tunable two-dimensional
nanostructures by improved nanospherelithography
Haibin Ni, Nanjing Univ. of Information Science &Technology (China) and Southeast Univ. (China); Xiangwei
Zhao, Southeast Univ. (China); Wang Ming, Nanjing
Normal Univ. (China)
A modified nanosphere lithography method that using anordered monolayer of composite PS sphere/silica gel arrays
as template to form a diverse range of tunable nano-patterns
in a small area with good reproducibility was demonstrated.
The critical improvement of this method is that it flexibly
using PS spheres and silica gel as combined etching masks
to produce different patterns. Silica gel is infiltrated in gapsof the PS spheres in self-assembly progress. The factors that
affect the infiltration height and uniformity are experimentallyinvestigated and discussed. Annular cavity/gaps arrays, bowl
arrays, close packed ring arrays, cylindrical column arrays andhole arrays are demonstrated by this method. Geometry sizeof these nano-patterns can be tuned over the range 10 nm to?500 nm with steps of ?5 nm during the fabrication progress.
Formation mechanisms of the close-packed ring arrays areexperimentally investigated. More importantly, most of the nanopatterns produced by this method could be integrated on thinfilms with conventional semiconductor fabrication techniques,212

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For sold-state quantum information processing, microcavities
containing semiconductor quantum dots have been
demonstrated effective as indispensable devices such as
efficient and indistinguishable single photon sources, andcoherent quantum-control devices. Ideal micropillar cavities
for 1.55 um quantum communication is still lacking. Hybrid
micropillar cavities, such as Ta2O5/SiO2-InP, Si/SiO2-InP, havebeen designed and used as 1.55um quantum-dot single-photon
sources. However, monolithically fabricated microcavities are
more attractive and necessary to quantum communication at
1.55um band. In this work, we propose monolithically producible
InGaAsP/InP-air-aperture microcropillar cavities as single photon
sources at 1.55-um telecommunication band. The design of airaperture resolves the problem of small refractive index contrast
in InP-based distributed-Bragg-reflector micropillars. Together
with tapered (layer thickness adiabatically decreased towards
the cavity center layer) distributed-Bragg-reflector structures,the lateral size (diameter) of these micropillar cavities can be
decreased to submicrometer scale. There are two modes withquality factors of ~1e4 and ~1e5, which are high enough for
efficient single photon emission from 1.55-um quantum dots. The
latter mode, especially, is able to realize coherently controllable
single-photon devices at 1.55 um. Compared with hybrid
micropillar cavities, such as Ta2O5/SiO2–InP or Si/SiO2-InP withwww.spie.org/pa·

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Conference 10027:
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similar pillar heights, the present cavities are of high quality and/or small size. Together with the easy, economic and monolithic
fabrication process, here proposed microcavities are better
candidates for 1.55-um InAs/InP quantum -dot single photon
sources and other quantum devices applied in silica-fiber based
quantum information system.

Gaussian beams to considerably narrower shape-invariant beams
accelerating (bending) along arbitrary trajectories. This work
is published at Nature Communications 7:10747 (DOI: 10.1038/
ncomms10747) (2016).

10027-28, Session 6

Experimental investigation of lightpropagation in engineered slottedphotonic crystal waveguides

Versatile asymmetric directional couplers
on silicon (Invited Paper)
Daoxin Dai, Zhejiang Univ. (China)
The coupling in a directional coupler (DC) has attracted lotsof attention as a basic block for photonic integrated circuits.
Most of previous work was focused on symmetrical directional
couplers (DCs) consisting of two identical optical waveguides, inwhich case light power can be transferred from one waveguideto the other one completely when choosing the length L of
the coupling region appropriately. Recently, an asymmetric DC(ADC) consisting of non-identical waveguides in the couplingregion has been attracting more and more attention becauseof the versatility for various useful applications. ADCs can beformed by combining two ore more waveguides with different
dimensions, shapes as well as bending radii for the core regions.
In particular, silicon nanophotonics developed in the recent years
provides a very good platform to make ADCs on silicon very
useful and interesting. In this paper, we give a review for recent
progresses of versatile ADCs on silicon, including the following
three parts: (1) ADCs for realizing ultracompact and broadband
PBSs; (2) ADCs for realizing mode (de)multiplexers; (3) ADCs for
power splitter used in microring resonators and Mach-Zehnderinterferometers.

10027-29, Session 6

Wavefront shaping through emulated
curved space in waveguide settings(Invited Paper)
Chong Sheng, Nanjing Univ. (China); Rivka Bekenstein,Technion-Israel Institute of Technology (Israel); Hui Liu,
Shining Zhu, Nanjing Univ. (China); Mordechai Segev,
Technion-Israel Institute of Technology (Israel)
Wavefront shaping for generating non-diffracting optical beams
can be achieved by various methods, ranging from annular slits,
axicon lenses, holograms, spatial light modulators, gratings,
metasurfaces and diffraction from nanoparticles. Importantly,
non-diffracting beams can also be generated in inhomogeneous
media, such as photonic crystals and photonic lattices. All theserequire wavefront shaping, that is typically done externally,outside the medium within which the beam is propagating.
However, wavefront shaping can also be done by shaping the
EM environment in which the wave is propagating. The fact thatthe propagation of EM waves in static curved space is analogous
to that in inhomogeneous media is the underlying principle ofemulating General Relativity (GR) phenomena in transformation
optics. Here, we show that using ideas inspired by GR yields
efficient beam shaping in waveguide settings. The concept isgeneral, applicable to many cases where wavefront beam shaping
in a waveguide platform is required. First, we fabricate the microstructured optical waveguide with the specific refractive index
emulating the curved space environment generated by a massive
gravitational object. This dielectric structure yields a very narrow
beam that remains non-diffracting for many Rayleigh lengths.
Second, with the same experiment system, we demonstrate theEinstein’s rings phenomenon, matching Einstein’s 80 years old
formula. Finally, we present a general formalism to transform

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10027-30, Session 6

Samuel Serna, Institut d’Électronique Fondamentale(France) and Lab. Charles Fabry (France); Weiwei Zhang,Institut d’Electronique Fondamentale (France); Xavier Le
Roux, Laurent Vivien, Eric Cassan, Institut d’ÉlectroniqueFondamentale (France)
Photonic Crystal Waveguides are key components to study
diverse phenomena in the linear and nonlinear regimes for
integrated circuits and rise as a promising platform to hostnovel materials. Nevertheless, serious limitations are manifest
when slow light is targeted, mainly the propagation losses.
Even though, photonic crystals are theoretically lossless, thepractical implementation is limited by the fabrication accuracy,
mainly during the lithographic and etching steps. Interestingstudies have been performed in W1-like photonic crystals inorder to engineer the losses for given group indices. Further,slot waveguides are known to suffer from larger roughnessinduced scattering extrinsic losses than Si wires due to a higher
electric field interaction regarding the continuity of the electricaldisplacement vectors.
We have performed a rigorous experimental study under
different approaches to determine the best compromise
regarding electronic beam lithography, group index, propagation
length and losses in engineered slotted photonic crystal
structures [Serna et al., Sci. Rep. 2016, in press]. The waveguidetransmission and dispersion were studied with different refractive
indices around n=1.45+/-0.05. The photon group delay wasmeasured as a function of the wavelength with integrated MZIand in external OCT techniques for long structures between
200 and 700 ?m. During the evaluation of SEM images, only
statistical variations were observed around the calibrated values.
Nevertheless, the optical characterization allowed studying
the statistical fluctuations and the propagation optical losses.
Furthermore, the presence of the flattened band was always
observed with the same bandwidth, offering robust dispersion
engineered long hybrid waveguides for that are particularlyinteresting for quantum, nonlinear and all-optical processing
integrated applications.

10027-31, Session 6

Lossless coupled modes in symmetricwaveguide array with non-uniform gain
and loss
Zhenzhen Liu, Jun Jun Xiao, Harbin Institute ofTechnology Shenzhen Graduate School (China)
Non-Hermitian systems in optics, are a fascinating platform
providing a lot of interesting applications. A typical example
is the well-known parity-time (PT) symmetric waveguides,
which experience a phase transition from the unbroken phaseto the broken one crossing the exceptional point. In opticalPT-symmetric system the gain and loss are generally uniformly
distributed. While for a non-uniform distribution of gain and loss,
there arises more fascinating phenomena, such as loss-induced
transmission, reversed pump dependence in lasers. In thesecases, the eigenvalues are always complex. To achieve lossless#PhotonicsAsia

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Conference 10027:
Nanophotonics and Micro/Nano Optics III
propagation in such systems is of importance. We show that infour coupled waveguides of identical geometry, that is always
possible by introducing additional gain or loss to balance theenergy propagating in the whole structure. We verify that by thegeneral coupled mode theory and the finite element method. In
addition, beam oscillation phenomenon is explored. Our results
prompt that non-uniform distribution of gain and loss offers extra
control of the eigenvalue dynamics in non-Hermitian system.

10027-33, Session 710027-32, Session 610027-34, Session 7

Highly reflective polarization-independent
subtractive tri-color filters exploitinga silicon nanodisk array overlaid withaluminum

Investigation of Ge1-xSnx/Ge quantumwell structures as optical gain media

Wenjing Yue, Sang-Shin Lee, Eun-Soo Kim, Kwangwoon
Univ. (Korea, Republic of); Duk-Yong Choi, The Australian
National Univ. (Australia)
Silicon (Si), known as the second-most-abundant material innature, has been predominantly adopted in the commercial
microelectronics industry. Owing to its salient features, suchas low cost and compatibility with the existing complementary
metal-oxide-semiconductor processing, Si is regarded as the best
candidate for the construction of optical devices. It was reported
that a Si nanowire (NW) formed on a Si substrate is suitable
for multi-color generation, whereby a wavelength-selective
coupling of the incident light with the guided modes of a vertical
Si NW renders a specific color. The reflection efficiency of Si
NW, however, is less than 40% due to the low reflectivity of Si.
Moreover, Si NW has extremely large aspect ratio, resulting in theuntenable fragility and unstable performance.
In this paper, we propose and demonstrate polarizationindependent structural subtractive tri-color filters of cyan,
magenta, and yellow with high reflection efficiency androbustness, by taking advantage of a aluminum (Al)-coatedlow-aspect-ratio Si nanodisk (ND) array that is formed on the
Si substrate. The Si ND, serving as a high index nanoscatterer,
can excite both magnetic dipole and electric dipole resonancesin the visible band. The light stored in the ND resonator ispreferably coupled to the high index Si substrate, giving rise toa highly suppressed reflection dip. By virtue of the Al overlay
and the symmetrical shape of ND, the proposed tri-color filters
can enable the high reflection efficiency of ~72%, which exhibit
threefold increment as compared with the Si ND-based structure,and polarization-independent property, respectively.

214

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Silicon and silicon carbide nonlinear andquantum photonics (Invited Paper)
Qiang Lin, Univ. of Rochester (United States)
No Abstract Available

Li-Chou Sun, National Chung Cheng Univ. (Taiwan); Hui
Li, H. H. Cheng, National Taiwan Univ. (Taiwan); Guo-En
Chang, National Chung Cheng Univ. (Taiwan)
An efficient Si-based laser is one of the most importantcomponents for photonic integrated circuits to break thebottleneck of data transport over optical networks. The
main challenge is to create gain media based on group-IV
semiconductors. Here we present an investigation of using
low-dimensional Ge1-xSnx/Ge quantum well (QW) structures
pseudomorphically grown on Ge-buffered Si substrates as optical
gain media for efficient Si-based lasers. Theoretical analysis ofband structures indicates that Ge1-xSnx well sandwiched by Ge
barriers can form type-I alignment at ? point with a sufficient
potential barrier height to confine carriers in the Ge1-xSnx well,thereby enhancing efficient electron-hole direct recombination.
Our calculations also show that Ge1-xSnx/Ge QW can provide
a larger optical gain than the bulk Ge1-xSnx counterpart, thus
reaching the transparent condition with a much smaller carrier
density. Furthermore, epitaxial growth of such Ge1-xSnx/
Ge QW structures was performed on Ge-buffer Si substrateusing low-temperature molecular beam epitaxy techniques.
Photoluminescence spectra from the grown Ge1-xSnx/Ge QW
structure were observed and analyzed. These results suggest thatGe1-xSnx/Ge QW structures are promising as optical gain media
for efficient Si-based light emitters.

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Conference 10027:
Nanophotonics and Micro/Nano Optics III

10027-35, Session 710027-36, Session 7

Wavelength-controlled manipulation ofcolloidal quasi-resonant quantum dots
under pulsed laser irradiation

Study of electro-absorption in tinincorporated group-IV alloy-based strainbalanced quantum well

Aleksey S. Tsipotan, Siberian Federal Univ. (RussianFederation); Aleksandr S. Aleksandrovsky, Kirensky
Institute of Physics (Russian Federation); Vitaliy V. Slabko,
Siberian Federal Univ. (Russian Federation)

Prakash Pareek, Ravi Ranjan, Mukul K. Das, Indian School
Of Mines (India)

Production of nanostructures consisting of semiconductor
nanoparticles (NPs) is of interest for number of applications.
Development of new methods of NPs’ manipulation
and aggregation of NPs into nanostructures with predefined geometry is also of considerable interest from thefundamental point of view. Under laser irradiation with properlychosen wavelengths, excitonic excitations will be induced.
Electrodynamical interaction between excited NPs is rather
universal and allows formation of wide variety of nanostructures
both of homo- and heterogeneous content. Theoretical approachfor study of interaction of NPs’ ensembles with laser lightincludes dipole-dipole approximation for NPs’ attraction and
Brownian dynamics computer modelling of NPs stabilized by
DLVO barrier. Main predictions of these studies are 1) Controlled
self-assembly of nanostructures containing mixed metal andsemiconductor NPs is possible via proper choice of wavelengthof laser inducing electrodynamical interaction. 2) Efficient
self-assembly of a pair of NPs must be expected in the regionof wavelengths redshifted with respect to plasmonic/excitonic
resonance. 3) Efficient self-assembly is possible in the regime ofnanosecond laser pulses with high enough repetition rate.
Experimental results are obtained for CdTe QDs with theexcitonic resonance at 520 nm. Six different samples of thesame colloid solution were irradiated at wavelengths from 540
to 570 nm. Modifications of absorption spectra of solutions after
irradiation was detected, being most prominent at 555 and 560
nm irradiation wavelengths. Analysis of spectra shows that up
to 47% of QDs were assembled into pairs. Therefore, possibilityof precise QDs manipulation via laser-induced electrodynamicalinteraction is demonstrated.

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Electroabsorption modulators (EAMs) have widely drawn
attention due to their application in optical processing, highspeed switching, low power dissipation etc. It would be very
useful to design Group IV semiconductors (Si,Ge) based EAM
to realize monolithic integrated chip. Fortunately, alloying
Germanium with ?-Sn(Tin) can effectively reduce the directbandgap of Germanium more than its indirect bandgap and,hence, a direct-bandgap GeSn alloy can be realized. This work
focuses on the potential of GeSn quantum well as an EAM in
midinfrared range. A 76Å thick Ge0.83Sn0.17layer is sandwiched
between two tensile strained Si0.09Ge0.8Sn0.11 layers to form a
type-I single strain compensated quantum-well (SSCQW). A fully
relaxed Ge0.872 Sn0.128 layer is used as a buffer layer. Firslty, theband profiles of conduction band and valence band in SSCQW
are calculated by Van de Walle model solid theory. Then, Eigen
state energies in SSCQW are evaluated for ? valley conduction
band (?CB), heavy hole band (HH) and light hole band (LH)from the self consistent solution of coupled Schrödinger andPoisson equations in presence of external electric field by finite
difference method. After evaluating Eigen energies, excitonic
electroabsorption coefficient for transverse electric (TE) mode iscalculated by using Fermi golden rule.
A significant absorption (1.2 x 104 cm-1) observed for ?CB1HH1 transition at 3.5 µm due to higher oscillator strength of
excitons. Quantum-confined Stark effect is also demonstrated
by redshifting of absorption peak wavelength. A significant
change in refractive index (?n) by using Kramers-Kronig integral,performance parameters like extinction ratio, figure of merit andchirping factor are also calculated.

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Conference 10028: Plasmonics II
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10028 Plasmonics II

10028-1, Session 1

10028-3, Session 1

Tailoring Light with Reflective
Metasurfaces (Invited Paper)

Metasurfaces for high-efficiency surface
plasmon coupler and active dispersion
compensation (Invited Paper)

Pin Chieh Wu, National Taiwan Univ. (Taiwan) andResearch Ctr. for Applied Sciences - Academia Sinica(Taiwan); Wei Ting Chen, Yao-Wei Huang, Wei-Yi Tsai,Pei Ru Wu, Ting-Yu Chen, National Taiwan Univ. (Taiwan);
Ching-Fu Chen, National Taiwan Univ. (Taiwan) andResearch Ctr. for Applied Sciences - Academia Sinica(Taiwan); Hui Jun Wu, Chun Yen Liao, National Taiwan
Univ. (Taiwan); Din Ping Tsai, Research Ctr. for Applied
Sciences - Academia Sinica (Taiwan) and National Taiwan
Univ. (Taiwan)
Metasurfaces enable abrupt changes to the electromagnetic
amplitude as well as phase of scattering light within a
subwavelength spatial region. They provide a great flexibility inlight manipulation and benefit the development in flat optics
and optically thin optoelectronic components. Metasurfaces
therefore show the abilities to tailor the properties of light andoffer a promising way for potential applications on integrated
devices. Here, we demonstrated reflective metasurfaces withbroad working bandwidth in visible frequencies. Several practicalapplications will also be performed and discussed. For example,
by using a 4-level phase gradient metasurface made of gold
cross nano-antennas, a dual-image meta-hologram with highefficiency is performed. A multi-color meta-hologram canalso be achieved by the implement of aluminium plasmonics.
Furthermore, a reflective polarization state generator is proposed
for the generation of arbitrary polarization states under a linear
polarized illumination.

Surface plasmon polaritons (SPPs) have recently found numerous
applications in photonics, but traditional devices to excite them
all suffer inherent low-efficiency issues. Here, we propose a
new SPP-excitation scheme and numerically demonstrate thatit exhibits inherently high efficiency (~94%). We fabricated ameta-coupler in the microwave regime and demonstrated thatthe achieved excitation efficiency for spoof-SPP reaches ~73%.
On the other hand, metasurfaces realized so far largely reply
on passive resonant meta-atoms, whose intrinsic dispersions
limit such passive meta-devices’ performances at frequencies
other than the target one. Here, based on active meta-atoms
with varactor diodes involved, we establish a scheme to resolvethese issues for microwave metasurfaces, in which the dispersive
response of each meta-atom is precisely controlled by an
external voltage imparted on the diode. We show that an active
gradient metasurface exhibits single-mode high-efficiency
operation within a wide frequency band, and the functionality of
our metasurface can be dynamically switched from a specularreflector to a surface-wave convertor.

10028-4, Session 1

Passive and active metasurface based on
metal-insulator-metal structure (Invited
Paper)
Junichi Takahara, Tianji Liu, Hideaki Hatada, Yusuke
Nagasaki, Osaka Univ. (Japan)

10028-2, Session 1

Modelling and ultrafast imaging ofdynamic near-field hybridization instrongly coupled plasmonic nanosystem
Alemayehu Nana Koya, Zuoqiang Hao, Jingquan Lin,
Changchun Univ. of Science and Technology (China)
In a series of numerical and analytical studies of plasmon
hybridization in closely spaced metal nanostructures, it has
been demonstrated that the spectral and spatiotemporalcharacteristics of the local fields in gap regions can be controlled
and enhanced by tailoring polarization and temporal profiles ofthe driving femtosecond pulses [1, 2].
In this report, we experimentally demonstrate the coherent
control of near-field excitation and coupling in gold nanosystemcomprised of split-ring dimer and nanorod that are separated
by a sub-20 nm gap. The near-field responses of gap plasmons
are controlled by manipulating the polarization and time delayof the femtosecond excitation laser pulses. The spatiotemporal
dynamics of the near-fields are mapped by the time-resolved
photoemission electron microscope (TR-PEEM) technique. The
experimental findings are supported by corresponding numericalresults calculated by the finite-element-time-domain (FDTD)
method.
[1] Alemayehu Nana Koya et al., J. Appl. Phys. 118, 113101 (2015).
[2] Alemayehu Nana Koya et al., J. Opt. 18, 055007 (2016).

216

Lei Zhou, Fudan Univ. (China)

SPIE Photonics Asia·

Metal-insulator-metal (MIM) structure is one of the promisingplasmonic structure for wide variety of applications from visible
to infrared region. It can be used as a nano-optical resonator asa meta-atom composed of metasurface beyond the diffraction
limit of light. A MIM resonator harvests light into a nano-gap as
an optical antenna and efficiently absorbs light into the gap as
gap surface plasmon (GSP) mode. However, applications arelimited as long as optical properties of the resonator is static due
to its fixed structures. Active control of optical properties of theresonator is needed for further functionality.
Here, we review principles and recent progress of a passive
metasurface based on the absorption control using static MIM
resonators. Applications of MIM resonators to plasmonic color
and a sky radiator are presented. In plasmonic color, we areable to control colors by designing reflection spectra that isdetermined by two absorption peaks between lower and higher
mode of GSP resonance, which is attributed to Fabry-Perot
interference of GSP. In a sky radiator, we design absorption
spectra matched to atmospheric window of 8-3micron by using
multi-sized MIM resonators. This also can be directly applied toinfrared emitters based on thermal radiation.
Then, we demonstrate an active metasurface composed ofreconfigurable plasmonic resonator based on metal-air-metal(MAM) structure. We realized the MAM resonator by a metal
nanowire (NW) suspended on a metal substrate. By applying
electrostatic voltage, the suspended NW can be pull down byelectrostatic force. This electromechanical response changes theresonant properties of MAM resonator.

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Conference 10028: Plasmonics II

10028-5, Session 2

Nanoscale imaging of local fewfemtosecond near-field dynamics within
individual nanostructures (Invited Paper)
Anders Mikkelsen, Lund Univ. (Sweden)
The local enhancement of few-cycle laser pulses bynanostructures opens up for spatiotemporal control of opticalinteractions on a nanometer and few-femtosecond scale.
However, spatially characterization of this dynamics poses amajor challenge due to the extreme length and time scales
involved. To resolve this issue we combine the femtosecondand attosecond time resolution of advanced laser systems with
the nanoscale spatial resolution of PhotoEmission Electron
Microscopy (PEEM) to study electron dynamics in nanoscale
structures. This allows for very sensitive measurementsof plasmonics fields, surface chemistry and pump-probe
experiments on ultrafast time scales - all in the same picture.
Using 5.5 fs laser pulses with a central energy around 1.6 eV
in an interferometric time-resolved PEEM setup, we observe
differences in near-field enhancement inside a variety ofnanostructures [1,2,3] already within the first few optical cycles .
The experiments are supported by finite-difference time-domain
simulations of similar structures. We find that field enhancement
effects can also be observed in III-V semiconductor nanowires,time and polarization changes are discussed.
We will finally demonstrate imaging using <100 attosecond laser
pulses with central energies between 30-100eV in combination
with PEEM (attoPEEM)[4,5]. We outline the clear pathway forusing such pulses for direct investigations of photon excitations
with sub-femtosecond precision
References[1] E. Mårsell et.al Nano Lett. 15(2015)6601[2] E. Lorek et.al, Optics express 23(2015)31460[3] E. Mårsell et.al, Appl. Phys. Lett. 107(2015)201111[4] A. Mikkelsen et.al., Rev. Sci. Instrum. 80(2009)123703.
[5] E. Mårsell et.al., Annalen der Physik, 525(2013)162.

10028-7, Session 2

Photoluminescence of Ag/Sn core/shell
nanoparticles
Bin Li, Lin Zhu, Ying Hu, Ying-Wei Lu, Hefei Univ. ofTechnology (China)
Recently, one of the promising applications of plasmonics is theintegration with Si-based photovoltaics. Particularly, the nearfield effect has attracted intense attention since the metallic
nanoparticles embedding in the crystalline or amorphous Si
layers could confine the electromagnetic field to enhance theoptical absorption cross-section of the photosensitive matrix, andeventually to improve the photovoltaic performances of Si-basedsolar cells. It is well known that the frequently used metallic
nanoparticles are either Ag or Au due to their fantastic surface
plasmon properties in the visible range. However, both noble
metals have energy levels close to the middle of the band gapof Si and therefore act as efficient recombination centers for theminority carriers. Instinctively, metallic Sn, a group-IV element,
has been proposed to be the ‘antenna’ in the plasmon assisted
solar cells. However, comparing with that of Ag nanostructures
the plasmon response of metallic Sn is too weak to be
employed. We therefore chemically synthesized Ag/Sn core/shell nanoparticles to take advantages of both Ag and metallic
Sn. In addition to the morphology and phase determinations by
TEM and XRD, photoluminescence and absorption properties
have been characterized to analysis the surface plasmon effectdepending on the configurations of the core/shell nanoparticles.
Furthermore, the near-field mappings of different configurations
have been performed by the finite element method as well.

10028-8, Session 210028-6, Session 2

Graphene oxide coated Au nanoparticles
composite structure for improved SERS
sensing
Bingfei Liu, Qi Wang, Tian Tian, Guoming Mao, Hao Liu, Jia
Chen, Xiankun Wang, Xiao-Min Ren, Beijing Univ. of Posts
and Telecommunications (China)
Surface-enhanced Raman scattering (SERS) is an effective
spectral analysis technique as its advantage of molecularfingerprint, ultra-sensitivity and non-contact. It is the mostpopular and easiest method to create SERS metal nanoparticles(NPs) combining magnetron sputtering deposition of noble metal
with rapid annealing. In this study, we have demonstrated an
approach to improve the SERS effect by using graphene oxide(GO) Au NPs composite structure. Here, we obtain the Au NPs
coated SOI substrate prepared by magnetron sputtering 4 nm Au
film and followed by rapid annealing treatment. The experimental
results indicate that the SERS intensity is maximum of the Au
NPs coated SOI substrate with the average particle diameter of
50 nm when the rapid annealing time is 30s and temperature is
500 degrees. Then, graphene oxide solution is spin coated on
the Au NPs to form the GO-Au NPs composite structure. The
morphology of GO-Au NPs have been characterized by scanningelectron microscope (SEM) and atomic force microscope (AFM).
Rhodamine 6G is used as the probe molecule to detect the SERS
intensity. The GO-Au NPs has an excellent SERS effect which

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can detect rhodamine 6G as low as 10-9M. Besides, comparedto the Au NPs without GO the GO-Au NPs has two times Raman
intensity enhancement of bands at 1365 cm-1 because of the
GO improving the SERS properties through strong ability ofadsorption the probe molecule and chemical enhancement
effect. Therefore, the GO-Au NPs composite structure shows apromising future to detect low concentration material.

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Optical interactions of a single AuNp on agold film
Xin Hong, Jingxin Wang, Dalian Univ. of Technology(China)Localized surface plasmon (LSP) and surface plasmon-polariton(SPP) effects have been hot topics in the last several decades
The coupling between two plasmonic modes associated withmetallic nano-particle and thin film plays an important role inbio-photonics. Especially for a single particle/film model which
can build a fundamental base for advanced nano-photonic
elements design and nano-optical measurement. However there
is little literature work can be found. In this paper, the interaction
between LSPR and SPR is studied in detail based on a structurecomposed of 60nm gold nano-particle, dielectric spacer and
50nm gold film by finite difference time domain (FDTD) method.
The LSPR mode influenced by the gold film was studied by
calculating its cross sections of scattering, absorption andextinction. With the aim to explore the coupling interaction, adielectric spacer with the thickness ranging from 2nm to 10 nm
was introduced to block the interaction. The results show thatat the thickness of 2nm, the LSPR associated with the particle isstrongly affected by producing a large red-shift to the red band.
This influence is very sensitive to the gap, when the particle isfurther away from the film, the peak LSPR wavelength is tuned
backwards. By changing the spacer thickness between theparticle and the film, the LSPR can be tuned to be closer to the#PhotonicsAsia

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Conference 10028: Plasmonics II

SPP, thus lead to an enhanced extinction cross section. The SPP
mode influenced by the AuNp was studied by calculating its peak
SPR wavelength. The calculation result indicates the addition of
the particle to the film causes the SPR curve broaden but thepeak wavelength shift is rather ignored.

[1] V. G. Veselago, The electrodynamics of substances withsimultaneously negative values of [epsilon] and u, Usp. Fiz. Nauk92, 517-526 (1964), [Soviet Physics Uspekhi 10, 509-514 (1968)].
[2] D. J. Bergman, Perfect imaging of a point charge in thequasistatic regime, Phys. Rev. A 89, 015801 (4 pp.) (2014).

10028-9, Session 2[3] A. Farhi and D. J. Bergman, Analysis of a Veselago lens in thequasistatic regime, Phys. Rev. A 90, 013806 (10 pp.) (2014).

Polarization state of light scattered fromquantum plasmonic dimer antennas(Invited Paper)[4] A. Farhi and D. J. Bergman, Non-quasi-static eigenstates ofMaxwell’s equations in a two-constituent composite medium andtheir application to a calculation of the local electric field of atime dependent point electric dipole in a at-slabs microstructure,
submitted for publication.

Zhipeng Li, Capital Normal Univ. (China)
Plasmonic antennas are able to concentrate and re-emit lightin a controllable manner through strong coupling between
metallic nanostructures. Only recently has it found that quantum
mechanical effects can drastically change the coupling strength
as the feature size approaches atomic scales. Here, we present
a comprehensive experimental and theoretical study of theevolution of the resonance peak and its polarization state as
the dimer-antenna gap narrows to sub-nanometer scale. We
clearly can observe the classical plasmonic regime, a cross-overregime where nonlocal screening plays an important role, andthe quantum regime where a charge transfer plasmon appears
due to interparticle electron tunneling. Moreover, as the gap
decreases from tens of to a few nanometers, the bonding dipole
mode tends to emit photons with increasing polarizability. Whenthe gap narrows to quantum regime, a significant depolarizationof the mode emission is observed due to the reduction of thecharge density of coupled quantum plasmons. These results
would be beneficial for the understanding of quantum effects on
emitting-polarization of nanoantennas and the development of
quantum-based photonic nanodevices.

10028-10, Session 3

Theory for the eigenstates of the fullMaxwell equations in some simple
composite structures (Invited Paper)David J. Bergman, Asaf Farhi, Tel Aviv Univ. (Israel)
Eigenstates of Maxwell’s equations in the quasistatic regime wereused recently to calculate the response of a Veselago Lens [1]to the field produced by a time dependent point electric charge[2, 3]. More recently, this approach was extended to calculate
the non-quasistatic response of such a lens. This necessitated a
calculation of the eigenstates of the full Maxwell equations in aslab structure where the electric permittivity [epsilon]1 of the slab
differs from the electric permittivity [epsilon]2 of its surroundings
while the magnetic permeability is equal to 1 everywhere [4].
These eigenstates were used to calculate the response of a
Veselago Lens to an oscillating point electric dipole sourceof electromagnetic (EM) waves. A result of these calculations
was that, although images with sub-wavelength resolution areachievable, as first predicted by John Pendry [5], those images
appear not at the points predicted by geometric optics. They
appear, instead, at points which lie upon the slab surfaces. Thisis strongly connected to the fact that when [epsilon]1/[epsilon]2= -1 a strong singularity occurs in Maxwell’s equations: This valueof [epsilon]1/[epsilon]2 is a mathematical accumulation point for
the EM eigenvalues. Unfortunately, many physicists are unawareof this crucial mathematical property of Maxwell’s equations.
We have now constructed a theory for the EM eigenstates ofthe full Maxwell equations in a composite structure, without any
restriction on the values of the constituent moduli [epsilon]i and[mu]i. This will be described, as will some simple applications. In
particular, it is now possible to analyze in detail the response of a

218

Veselago Lens when both [epsilon]1/[epsilon]2 = -1 and mu1/mu2= -1.

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[5] J. B. Pendry, Negative refraction makes a perfect lens, Phys.
Rev. Lett. 85, 3966-3969 (2000).

10028-11, Session 3

Active multiple plasmon-induced
transparencies with detuned asymmetricmulti-rectangle resonators
Dongdong Liu, Xuzhou Institute of Technology (China);
Jicheng Wang, Jiangnan Univ (China); Jian Lu, Nanjing
Univ. of Science and Technology (China)
The phenomenon of plasmon-induced transparency (PIT) is
realized in surface plasmon polariton waveguide at near-infrared
region. By adding one and two resonant cavities, the PIT peaks
were achieved due to the destructive interference between
the side-coupled rectangle cavity and the bus waveguide. The
proposed structures were analyzed by the coupled-mode theory
and demonstrated by the finite element method. The simulation
results showed that for three rectangle resonators, not only can
we manipulate each single PIT window, but also the double PIT
windows simultaneously by adjusting one of the geometricalparameters of them; for four rectangle resonators, by changing
the widths, the lengths and the refractive index of three cavities
simultaneously, we would realize treble PIT peaks and induce anoff-to-on PIT optical response. Our novel plasmonic structures
and the findings pave the way for new design and engineeringof highly integrated optical circuit such as nanoscale opticalswitching, nanosensor, and wavelength-selecting nanostructure.

10028-12, Session 3

Mechanism of resonant perfect opticalabsorber, design rules, and applications(Invited Paper)
Zhiqiang Guan, Hongxing Xu, Wenqiang Wang, Wuhan
Univ. (China)
The mechanism of resonant perfect optical absorber is revealedby coupled mode method. A fully mode dispersion analysis isprovided by the phase plots of scattering coefficients on eachinterface. The structures include dielectric/structure/dielectric
system and dielectric/structure/film/dielectric system. The
negative role of modes at input surface and the positive roleof modes at output surface are shown for the perfect opticalabsorption. And the non-zero order quasi waveguide mode in the
dielectric film is proved to play a key role for the perfect opticalabsorption when the film is on output surface. The sufficientand necessary conditions of perfect optical absorption are
given by three analytical formulae and serve as the design rules.
The dependence of perfect optical absorption wavelength on
geometry parameters can be explained by the three formulae.

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Conference 10028: Plasmonics II

The advantages of widely tunable perfect optical absorption
wavelength, high Q factor and the wide applications such as
sensing, modulation and detection are reviewed for the resonant
perfect optical absorbers.

10028-13, Session 3

Plasmonic 3D conductive coupling in a 3D
metamaterial (Invited Paper)
Jiafang Li, Zhi-Yuan Li, Institute of Physics (China)
In this talk, we report our recent studies on a 3D conductive
coupling mechanism, which induces significant Fano resonances
in a 3D metamaterial (MM). The 3D MMs are formed byintegrating vertical U-shape split-ring-resonators (SRRs) orvertical rectangular plates along a planar metallic hole arraywith extraordinary optical transmission (EOT) built by means ofhomemade focused ion-beam (FIB) folding technique. In sucha configuration, intensified vertical E-field is induced along themetallic holes and naturally excites the electric resonances ofthe vertical structures, which form non-radiative “dark” modes
due to the symmetry constraints. These 3D conductive “dark”
modes strongly interfere with the “bright” resonance mode of
the EOT structure, which generate significant Fano resonanceswith both prominent destructive and constructive interferences.
Moreover, compared with the capacitive and inductive coupled
Fano resonances that degrade drastically upon small structuraldeviations, the demonstrated 3D conductive coupling induced
Fano resonances are highly scalable, universal, robust andimmune against both fabrication and illumination imperfections.
These 3D MMs with prominent and robust Fano resonances
exhibit an extremely high sensitivity to refractive index of theenvironments in the near infrared wavelength region.

10028-14, Session 3

Superlens imaging with surface plasmon
polariton cavity in object space
Haiyang Chen, Chinhua Wang, Soochow Univ. (China)
In this paper, superlens imaging with double surface plasmon
polarition cavity in object space is proposed. A silver layer
is added to above the object mask to form surface plasmon
polariton cavity in object space, which helps to greatly enhanceevanescent waves generated by objects. As a result, better
object imaging contrast can be obtained compared with thesurface plasmon polariton cavity in imaging space by amplifying
the higher frequency componments while suppressing the longrange plasmon mode. Due to the SPP resonance, in the cavity,
the image field exhibits a much extended depth of imaging field. We almost can obtain the same image within the entire cavityof length of 20nm when the linewidth of the object layout of
traces is set to 45 nm (about 1/9 wavelength). The proposed
method provides a practically feasible and relatively simple way
to achieve images beyond the optical diffraction limit with both
high resolution and large depth of imaging field. This is confirmedby the electric field distributions and optical transfer functionof the system. The distinguishing feature of the cavity structureis that the higher frequency wave vectors become dominant
and the low-frequency evanescent waves will be far away fromthe resonance. The physical mechanism of the imaging quality
improvements based on surface-plasmon polaritons theory is
discussed. Finite-difference time-domain analysis method is usedin the simulation.

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10028-15, Session 4

Weyl points in plasmonic photonic crystals(Invited Paper)
Mingli Chang, Meng Xiao, Wenjie Chen, Che Ting Chan,
Hong Kong Univ. of Science and Technology (Hong Kong,
China)
Weyl point is a stable nodal point with two bands degenerate at
one point. Such a topological point behaves as if it is a magnetic
monopole in momentum space and can act as a source or sinkof Berry flux. It cannot be removed until two Weyl points with
opposite topological charges annihilate with each other. Weyl
points have been observed in the electronic system and theanalog in classical wave, such as EM wave and acoustic wave
have also been studied. However, Weyl photonic crystals typicallypossess complicated structure and therefore such Weyl points
are difficult to be designed at the plasmonics scale and visible
light frequency. In this work, we propose a structurally simple
plasmonic photonic crystal with Weyl points in its band structure.
By analyzing the tight binding model of the system, we findthat the Hamiltonians at some high symmetry k points can be
reduced to a Weyl form with topological charges 1 or 2. Also wedesign the real structures with plasmonic photonic crystal andverify that such Weyl points can be designed and realized at
optical frequencies. Furthermore we also calculated the gaplessboundary modes connecting the upper and lower cones and therobust one-way transport has also been checked in this system.
Such materials with Weyl points provide us more possibilities to
explore the interesting physics of topological bands in metallic
structures at the nano-scale.

10028-16, Session 4

Control and mapping ultrafast plasmons
with PEEM
Boyu Ji, Jiang Qin, Peng Lang, Alemayehu Nana Koya,
Zuoqiang Hao, Toshihisa Tomie, Jingquan Lin, Changchun
Univ. of Science and Technology (China)
Plasmon resonance assisted strong near field enhancement has
attached great attention in various fields. On one hand, effort has
been made to pursuit resonant field enhancement in the researchof excitation and control of localized surface plamsons (LSP). On
the other hand, off-resonant excitation of LSP in nanostructureis also found to have great potential applications in some fields,
e.g. biomedicine. We demonstrate subwavelength imaging andcontrol of the localized near-field distribution under resonant and
off-resonant excitation of identical gold bow-tie nanostructure
through photoemission electron microscopy (PEEM). The results
show that the near field can be controlled and a better control
effect is achieved for the resonant excitation than the case ofoff-resonant excitation. Furthermore, we found that phase of thelocalized near field goes inverted after its position shift for the
single pulse control scheme, while the phase keeps unchanged
after position shift for the two orthogonally pulses control.
The LSP in bowtie structure is imaged by a pair of ultrafast
femtosecond laser pulses. The results show that by combining
the pump-probe technology with PEEM, a series of images of
LSP modes temporal evolution on different tips of the bowtie
are obtained. We also theoretically investigated the opticalresponse of asymmetric nanocross and a coupled ring dimer-rod
nanosystem under ultrafast laser illumination in this work. These
works opens the way for the applications of ultrafast plasmonsuch as in the field of ultrafast optical switching.

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Conference 10028: Plasmonics II

10028-17, Session 410028-37, Session Post

Plasmonic nanostructure fabrication andnear-field optical characterization (Invited
Paper)A Fabry-Perot plasmonic modulation withgraphene-based silicon grating in midinfrared region

Zheyu Fang, Peking Univ. (China)

Xiaosai Wang, Jicheng Wang, Jiangnan Univ. (China)

Plasmonics deals with the phenomena of collective vibrationof electrons in the interface between metallic and dielectric
media. With the advanced nanofabrication techniques, a broad
variety of nanostructures can be designed and fabricated forplasmonic investigations at nanoscale. In this presentation, we
will demonstrate our latest results of the design of new plasmonicnanostructures and the characterization of surface plasmon
nanostructures with 2D materials by using Scanning Nearfield Optical Microscopy (SNOM), which is one of the uniquecharacterization tools for nano-optical detection, and othertechniques, and discuss some fundamental properties for both
localized surface plasmons and surface plasmon polaritons arisea new insight and understanding for the electro-optical devices,such as plasmonic PL control, active plasmonic modulator anddetectors for energy harvesting.

We propose an ultra-compact graphene-based plasmonic
modulation that is compatible with complementary metaloxide-semiconductor (CMOS) processing. The proposed
structure uses a monolayer graphene as a mid-infrared surface
waveguide, whose optical response is spatially modulatedusing electric fields to form a Fabry-Perot cavity. By varying
the voltage acting on the cavity, the transmitted wavelength ofthe device could be controled at room temperature. The finite
element method (FEM) has been employed to verify our designs.
This design has potential applications in the graphene-based
silicon optoelectronic devices as it offers new possibilities fordeveloping new ultra-compact spectrometers and low-cost
hyperspectral imaging sensors in mid-infrared region.

10028-18, Session 4

Polarization to the field enhancement by agold dimer

Photocurrent enhancement by utilizing
unidirectional excitation of surface
plasmons

Xin Hong, Zheng Jin, Dalian Univ. of Technology (China)

Mehdi Afshari Bavil, Zhi Liu, Wuwen Zhou, Chuanbo Li,
Buwen Cheng, Institute of Semiconductors (China)
For optical communication technology photodetectors
which converts optical signals into electrical signals havegreat importance. Si has been recognized as the excellent
photodetector material compared to III-V based devices
due to lower multiplication noise. Ge is introduced to adjust
the absorption at telecommunication wavelengths which iscompatible with complementary metal oxide semiconductor(CMOS) process.
Nanoplasmonics exploiting surface plasmons, with the abilityof controlling andmanipulating of optical signals, provides aplatform for developing and optimizing various nanophotonic
components,especially photodetectors. Potential geometries
to excite SPPs are direct-coupling configurations such as
subwavelength nanohole arrays and nanoslits or side-couplingof SPPs via grooves, patches and circular grating which the SPPs
can be controlled and unidirectionally propagate.
In this paper we propose, design and demonstrate a novel
plasmonics based photodetector for operating wavelength of1550 nm. Our proposed structure is a circular configuration
including sub-wavelength slit and grooves in a metallic layer
surrounding a Si-Ge photodetector located at the center.
By tailoring the distance between slit and grooves and theseparation between the core and slit, SPPs can be steered to
predominantly propagate toward center. The most importantfeature of this structure is that top electrode ring can considered
as much as possible narrow to avoid light reflection.
Our results shows that SPPs assists in light absorption andenhances the photodetection and downscals the dimensions.
Moreover the structure is Si-based and CMOS process compatible
which make it very attractive for industrial purposes. The
photodetection was enhanced about 13 times which is very
considerable.

220

SPIE Photonics Asia

10028-38, Session Post·

Due to the effect of plasmonic coupling, gold nanoparticle dimers
have been paid more attentions especially in bio-imaging. The
coupling effect existing at the gap between a closely linked
particle pair can make the local field strongly enhanced. It is wellestablished that the angle between the excitation polarizationand the dimer axis plays a dominant role in the excitation ofplasmonic coupling. However due to the demand to remove theillumination beams in the cross-polarization detection method,the excitation and collection is vertical to each other whichmakes the angel relationship to the polarization can not follow
the established one. Thus, in this paper, we present a model tocalculate the electric amplitude field distribution of a gold dimer
by using finite-difference time-domain (FDTD) method. wesimulate a gold dimer under the illumination of a highly focused
beams from a microscopy objective. The scattering field collected
on a single detector is amplified by heterodyne interference witha reference light. The far-field scattering distributions both in
Ex and Ey vary with the polarization rotation were calculated.
This method provides a way to evaluate a gold dimer size down
to nanometer level. The simulation results show that for such amodel, 45degrees between the excitation polarization and thedimer axis can produce an optimum signal. The enhancement
thus obtained is ~7.26 fold while the variation between peakpeak can reach ~ 4.41 fold compared to a single plasmoic particle
during the rotation of the polarization.

10028-39, Session Post

Surface plasmon resonance scattered by adielectric sphere
Xin Hong, Xuejie Yin, Dalian Univ. of Technology (China)
It is well known that when total internal reflection occurs at theinterface between high to low refractive index, evanescent field
will go into the media with low refractive index. This field canbe scattered by a small dielectric particle on the surface. With
the development of near field optics in which evanescent filed
plays a dominant role, the scattering by a particle becomes
crucial to understand the underneath physics for the design ofnovel nano-photonic device. To amplify the scattering signal,an enhanced filed is desirable. Thus in this paper, with the aim

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Conference 10028: Plasmonics II

to enhance the scattering field we introduced a thin gold film.
Based on Fresnel equation, the introduction of the metallic film
causes an amplified transmission coefficient resulted from theexcitation of surface plasmon resonance on the thin metallic
film. Further a polystyrene bead at the diameter of 200nm and
800nm was employed to test the model. The microscopic local
refractive index associated with the polystyrene beads increases
when the diameter becomes bigger, thus larger angle is needed
to excite the local surface plasmon resonance. Polystyrene beads
at diameter of 800nm requires a larger angle which is beyond thenumerical aperture of the objective can provide. In this case thecondition to excite SPR can not be matched, which in turn shuts
up the enhancement. Theoretical and experimental results agree
well with each other that the locally excitated surface plasmon
play a dominant role in the field enhancement scattered by thesphere.

10028-40, Session Post

Analysis of asymmetric hybrid rib-slot-rib
surface plasmon waveguide with highconfinement mode
Kai Zheng, Zuxun Song, Northwestern Polytechnical Univ.
(China)The hybrid rib-slot-rib surface plasmon waveguide where a
combined rib-slot-rib structure is added on the metal substrate
within a low-index gap region with asymmetric structures is
proposed using finite element method. Two types of asymmetricstructures are introduced and their modal properties are
discussed and compared to the traditional long range surface
plasmon waveguide. Our designed structures can provide
enhanced confinement energy within the gap region at properparameters. Our simulation results is a guide for turning
properties of plasmonic waveguide and providing ways for
improved electromagnetic energy confinement in surface
plasmon waveguide.

10028-41, Session Post

Multi-wavelength band-pass plasmonic
splitter with nanodisk cavity
Maojin Yun, Kai Li, Qingdao Univ. (China)
A novel and simple multi-wavelength band-pass filter based on
metal-insular-metal (MIM) waveguide with different nanodisk
cavity is proposed and investigated numerically by FiniteElement-Method (FEM) simulations. According to resonant
theory of nanodisk, multi-wavelength band-pass filter canbe achieved for different wavelength. It also shows that thetransmission characteristics of the filter and the resonant
wavelength can be easily manipulated by changing the gap
between nanodisk and straight waveguide or changing the radiusof the nanodisk. This kind of plasmonic waveguide filter may
become important promising application in highly plasmonic
integrated circuits.

10028-42, Session Post

Cavity-enhanced ultra-thin aluminumplasmonic resonator for surface-enhanced
infrared absorption spectroscopy
Wei Wei, Jinpeng Nong, Chongqing Univ. (China); Linlong
Tang, Chongqing Institute of Green and Intelligent
Technology (China); Xiao Jiang, Na Chen, Peng Luo,
Chongqing Univ. (China)

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Owing to the advantages of natural abundance, low cost, andamenability to manufacturing processes, aluminum has recently
been recognized as a highly promising plasmonic material that
attracts extensive research interest. Here, we propose a cavityenhanced plasmonic resonator for surface enhanced infraredabsorption spectroscopy using patterned ultra-thin aluminum
micro/nano structure. The considered resonator consists of apatterned ultra-thin structure, a dielectric layer and a reflective
layer. In such structure, the resonance absorption is enhanced by
the Fabry-Perot cavity formed between the patterned structure
and the reflective layer. An optical model is built employing
the finite element method to investigate the influence of thestructural parameters on the absorption characteristics of theresonator, including the thickness, occupation ratio, period of
the patterned structure and the thickness of the dielectric layer.
The enhanced infrared absorption characteristics can be used forinfrared sensing of the adsorbed molecules. When the resonatoris covered with a molecular layer, the resonator can be used asa surface enhanced infrared absorption substrate to enhance
the absorption signal of the bimolecular. A high enhanced factorof 5?104 can be achieved when the resonance wavelength ofresonator is adjusted to match the desired vibrational modeof the molecular. Such a cavity-enhanced plasmonic resonator,
which is easy for practical fabrication, is expected to havepotential applications for infrared sensing with high-performance.

10028-43, Session Post

simulation of two-dimensional gratings for
SERS-active substrate
Wenlong Zou, Jianhong Wu, Soochow Univ. (China)
Raman spectroscopy provides intrinsic vibrational and rotationalmode of molecules in materials, which is widely used in chemical,
medical and environmental domain. As known, the magnitudeof surface enhanced Raman scattering can be amplified
several orders. Nowadays, common Raman scattering has been
gradually replaced by surface enhanced Raman scattering in low
concentration detection domain. Generally speaking, the signal of
surface enhance Raman scattering on periodic nanostructures ismore reliable and reproducible than on irregular nanostructures.
In this paper, two-dimensional gratings coated by noble metal areused as SERS-active substrate. The surface plasmon resonancecan be obtained by tuning the period of two-dimensional
grating when the excitation laser interacts on the grating. The
local electric field distribution is simulated by finite-differencetime-domain (FDTD). The wavelength of 632.8nm and 785nm
are usually assembled on commercial Raman spectrometer.
The optimization procedure of two-dimensional grating period
is simulated by FDTD for above two wavelengths. The relation
between the grating period and surface plasmon resonance isobtained in theory. The parameters such as depth of photoresist
and thickness of coated metal are systematic discussed. The
simulation results will greatly guide our post manufacture, which
can be served for the commercial Raman spectrometer in SERS
detection.

10028-44, Session Post

Hydrogen-regulated chiral
nanoplasmonics
Xiaoyang Duan, Simon Kamin, Max-Planck-Institut fürIntelligente Systeme (Germany); Florian Sterl, Harald
Giessen, University of Stuttgart (Germany); Na Liu, MaxPlanck-Institut für Intelligente Systeme (Germany) andUniversity of Heidelberg (Germany)In this paper, we demonstrate a hydrogen-regulated chiropticalresponse in hybrid plasmonic metamolecules in the visible#PhotonicsAsia

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Conference 10028: Plasmonics II

spectral range. Here, Mg works not only as active material forhydrogen uptake but also as plasmonic material for resonant
coupling with the satellite gold (Au) particles. Each metamoleculeconsists of coupled hybrid components that are arranged in aprescribed chiral geometry to generate a chiroptical response.
Au particles are particularly employed here to assist Mg particles
for achieving sharp and pronounced CD spectra. Such chiropticalresponse can be switched on/off by dynamically unloading/loading hydrogen in real time. In addition, energy dispersive X-ray
spectroscopy (EDX) reveals the morphology changes of the Mg
particles that result from hydrogenation and dehydrogenation
processes. With integration of appropriate active materials, ourdesign scheme can be generalized to create sensitive chiralplatforms for a variety of gas detection, given the high sensitivityof CD spectroscopy. This could provide a powerful addition to theconventional sensing paradigm.

10028-45, Session Post

Huang Tao, Jiajian Wang, Wei Liu, Ziwei Li, Zheyu Fang,
Feng Lin, Xing Zhu, Peking Univ. (China)
Unidirectional SPP (Surface plasmon polaritons) couplers which
can couple the SPPs from the free-space light to a desired
direction or regio, especially actively tuning the propagation
direction of SPPs by additional external control, is very important
for the on-chip plasmonic devices. In previous studies, actively
controlled and unidirectional SPP launchers usually havelarge longitudinal dimensions (>10?, perpendicular to the SPP
propagation direction along the metal surface). In this paper, wedemonstrated spin-controlled directional launching of surface
plasmons at the subwavelength scale. The total size of the
SPP launcher is only about 320 nm in horizontal direction and180 nm in vertical direction. The principle is based on opticalspin’s effect for the geometric phase of light. The slope of thestructures decides the spin-related geometric phase and theirrelative positions decide the distance-related phase. Therefore
we can introduced the spin’s effects on the phase of the SPPs
excited by a curved slit through the slope. Based on this idea, we
designed a curved nanoslit pair and studied the spin’s control
towards the propagation direction of the SPPs, in this nanoslit
pair, in both theory and simulation. The results showed that thelaunched SPPs propagate towards the right direction when theincident light is right-handed circularly polarized light and thelaunched SPPs propagate towards the left direction when theincident light is left-handed circularly polarized light. Further,
we conducted the SNOM experiment to testify our theory andsimulation and the shape and period of the interference fringes
has good agreement with the theory and increase the credibilityof our experiment results.

Controllable unidirectional emission ofelectric dipole coupled to plasmonic
bowtie antenna
Jun-Jun Xiao, Harbin Institute of Technology Shenzhen
Graduate School (China); Xiao Ming Zhang, Harbin
Institute of Technology (China)
Nanoantennas have been proved to be a good platform to tune
the emission properties of a localized source (e.g. an active
electric dipole). Besides the enhancement of the emission
efficiency, it is also feasible to control the radiation directivityof a dipole by utilizing the plasmon resonance modes of222

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10028-19, Session 5

Metal nanogap structure-based
plasmonics and biomedical applications(Invited Paper)
Jwa-Min Nam, Seoul National Univ. (Korea, Republic of)

Spin-controlled directional launching of
surface plasmons at the subwavelengthscale10028-46, Session Post

these antennas. Here, we analyze the angular emission on
the in-plane electric dipole modes of gold bowtie antenna.
When the nanostructure is excited by a nearby dipole source,
highly emission directionality can be obtained. Furthermore,by controlling the the position of the dipole source, strong
modulation in the angular emission of the dipole source occur
due to variation of the amplitude, the relative phase difference,and the orientation of the induced dipolar modes in the system.
We show the directional effects with full-wave numericalsimulations and a model of two electric dipoles interference .

Designing, synthesizing and controlling plasmonic nanostructureswith high precision and high yield are of paramount importancein optics, nanoscience, chemistry, materials science, energy
and nanobiotechnology. In particular, synthesizing and utilizing
plasmonic nanostructures with ultrastrong, controllable andquantifiable signals is key to nanoantenna, plasmonics-driven
chemical reaction, various chemical and biological detection
and biological imaging applications. Here, I will introduce
newly emerging DNA-engineered plasmonically coupled andenhanced nanoprobes with strong, controllable and quantifiable
signals including nanogap-enhanced Raman scattering, show
their potentials in addressing some of important challenges inscience, and discuss how these new materials can lead us to
new breakthroughs in various technologies including biomedical
technologies.

10028-20, Session 5

Changing surface plasmon modes by
optical spin-orbit interaction
Feng Lin, Jiajian Wang, Wei Liu, Xing Zhu, Peking Univ.
(China)The optical spin-orbit interaction is that a coupling of the
intrinsic angular momentum (photon spin) and the extrinsic
momentum (orbital angular momentum) [1-2]. The effect isusually observed when the light passes through an anisotropic
and inhomogeneous medium. For instances, the optical spin
Hall effect, beam displacement and momentum shift due to theoptical spin, was observed at the medium interface. In plasmonic
structures, the surface plasmons travel along the path that canbe defined to within a subwavelength scale by the geometricpatterns of the structures, which generate a significant opticalorbital angular momentum. In our work, on the Au thin film
deposited on glass substrates, we fabricate the subwavelength
holes by focused ion beam, which form the ring shape. Using thescanning near-field optical microscope, the different propagation
modes of surface plasmons has been observed for the excitation
light with the left and right handed circular polarization,
respectively. Based on the conservation of total optical angularmomentum in this circular system, the coupling effect of thespin and orbital angular momentum can be deduced from themeasured and simulated distribution of electric fields.
References:[1] Shitrit, N.; Bretner, I.; Gorodetski, Y.; Kleiner, V.; Hasman, E.
Nano Lett. 2011, 11, 2038.
[2] Shitrit, N.; Yulevich, I.; Maguid, E.; Ozeri, D.; Veksler D.; Kleiner,
V.; Hasman, E. Science 2013, 340, 724.

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Conference 10028: Plasmonics II

10028-21, Session 510028-23, Session 5

Controlling the polarization state of lightwith plasmonic metastructures (Invited
Paper)

Robust plasmonic tips fabricated by thetapering of composite hybrid silicate
microfibers with metallic core (Invited
Paper)

Ruwen Peng, Renhao Fan, Xiang Xiong, Mu Wang, Nanjing
Univ. (China)
In this talk, we present our recent work on controlling thepolarization state of light with plasmonic metastructures.
First, we illustrate an approach to tune efficiently the phasedifference of light in two orthogonal directions by controlling
the time retardation with a microstructured surface. Second,
we demonstrate the general mechanism to construct thedispersion-free metastructure, in which the intrinsic dispersionof the metallic structures is perfectly cancelled out by the
thickness-dependent dispersion of the dielectric spacing layer.
By selecting the structural parameters, the polarization stateof light can be freely tuned across a broad frequency range,
and all of the polarization states on the Poincaré sphere canbe realized dispersion free. Third, we present a freely tunable
polarization rotator for broadband terahertz waves using ametastructure, which can conveniently rotate the polarization ofa linearly polarized terahertz wave to any desired direction withnearly perfect conversion efficiency. The investigations provide
some guidelines to control the polarization state of light at
subwavelength scale.

10028-22, Session 5

Tailored and reconfigurable opticalproperties using plasmonics (Invited
Paper)
Maiken H. Mikkelsen, Duke Univ. (United States)
Hybrid materials structured on the molecular scale hold thepromise to realize optical properties that are drastically different
from their bulk counterparts. For example, metal-dielectric
nanocavities may tightly confine light to small mode volumes
resulting in strongly increased local density of states. In this talk,I will describe recent experiments utilizing a dynamically-tunable
plasmonic platform where emitters are sandwiched in a sub-10nm gap between colloidally synthesized silver nanocubes and a
metal film. Incorporating CdSe/ZnS semiconductor quantum dots
into the nanocavities enables demonstration of an ultrafast (<11ps) yet efficient source of spontaneous emission, corresponding
to an emission rate exceeding 90 GHz [Nat. Commun. 6, 7788
(2015)]. We show an increase in the spontaneous emission rate ofa factor of 880 and simultaneously a 2,300-fold enhancement in
the total fluorescence intensity, which indicates a high radiative
quantum efficiency of ~50%. Additionally, at a surface fill fractionof ~20%, these film-coupled nanocubes behave as spectrally
selective perfect absorbers which can be tuned from the visible
to the near-infrared utilizing inherently large-area solution-based
deposition techniques [Adv. Mater. 27, 8028 (2015)]. Finally, theplasmon resonance can be tuned electrically over 100?nm in thevisible wavelength range by applying a bias across the nanoscale
gap which causes changes in the gap thickness and dielectric
environment [Appl. Phys. Lett. 108, 183107 (2016)]. The observed
tuning range is greater than the full-width-at-half-maximum of
the plasmon resonance, resulting in a tuning figure of merit of
1.05 and a tuning contrast greater than 50%.

Afroditi Petropoulou, National Hellenic Research
Foundation (Greece) and Univ. of Peloponnese (Greece);
Grigoris Antonopoulos, National Hellenic Research
Foundation (Greece); Paul Bastock, Christopher Craig,
Univ. of Southampton (United Kingdom); Georgios
Kakarantzas, National Hellenic Research Foundation(Greece); Daniel W. Hewak, Michalis N. Zervas, Univ.
of Southampton (United Kingdom); Christos Riziotis,
National Hellenic Research Foundation (Greece)
The development of plasmonic devices for sensing applications
can offer high sensitivity and a dramatic improvement to thedetection limits due to the high field enhancement at the metal
surfaces. The platform proposed here is a hybrid microfiber
comprising a metal core and a glass silicate cladding that canbe further engineered by a suitable diameter tapering process
in order to achieve a field enhancement at the metal/dielectricinterface. The existence of a glass cladding not only serves asa mechanical host for the metal core, but also provides easeof handling regarding the tapering process providing also anenvironmentally robust platform for device’s manipulation. The
advantages of this composite material system over pure metal
tips are the absence of impurities and the multiple excitationsof the plasmon modes due to the total internal reflection at
the glass/air interface. The improved field enhancement at theapex of these tapered microwires was calculated through Finite
Element Method (FEM) simulations. Enhancement factors up
to 10^4 were theoretically observed for this type of tapered
microwires. The use of different metals having different melting
points, viscosity and thermal expansion coefficients as well as
the use of composite fibers with different glass and metal core
diameter has enabled the optimization of the fiber tapering
process conditions in order to achieve tapered microwires withthe desirable geometrical and operational characteristics.

10028-24, Session 5

The electric field enhancement and spatial
resolution of a metal-coated tapered fiber
tip using internal radially polarized vector
beam
Fanfan Lu, Ting Mei, Northwestern Polytechnical Univ.
(China)No Abstract Available.

10028-25, Session 5

Steering the scattering direction ofplasmonic nanoantenna by spin-orbit
coupling effect
Qiang Zhang, Jun-Jun Xiao, Harbin Institute of Technology
Shenzhen Graduate School (China)
It has been found that optical surface waves have intrinsic
transverse spin angular momentum (TSAM) whose direction islocked by the corresponding complex wave vector. This TSAMlocking feature allows unidirectional excitation of typical optical

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223

Conference 10028: Plasmonics II

surface waves [such as surface plasmon polaritions (SPPs)] by ananoscatter due to the spin-orbit coupling effect. Here we showthat the spin-orbit coupling effect of SPPs can be implemented
to tune the far field scattering direction of carefully designed
plasmonic nanoantenna. By analyzing the angular spectrum of
the fields produced by a circular polarized electric dipole (CPED),
we reveal that the TSAM locking feature of surface waves isinherently related to the asymmetric interference of CPED in thenear field regime rather than in the far field regime. However, it isshown that in a plasmonic nanoantenna involving the spin-orbit
interaction of SPPs, the far field scattering pattern of the antenna
can also be controlled by the helicity of the incident wave. As
an illustration, we exemplify that by a nanoantenna combining
a silver sphere and a silver nanorod. The theoretical results are
confirmed by numerical calculations. Our results may be usefulin spin-dependent photonic applications such as directional lightemission and optical micromanipulation.

10028-26, Session 5

Strong coupling between plasmonicresonances and molecular excitons (Invited
Paper)Min Qiu, Xingxing Chen, Zhejiang Univ. (China); Yu-Hui
Chen, Univ. of Otago (New Zealand); Jian Qin, Ding Zhao,
Zhejiang Univ. (China); Boyang Ding, Richard J. Blaikie,
Univ. of Otago (New Zealand)
Strong light-matter interactions build upon fast energy exchange
between atoms (molecules) and electromagnetic modes in acavity, which leads to cavity-atom mode hybridization, withgreat potentials to be applied in quantum information processing
and the manipulation of atomic (molecular) properties. On
the other hand, plasmonic cavities represent a very promising
platform towards the fundamental limit of controlling lightmatter interaction, e.g. single atom-photon couplings, sincethese nano-cavities can provide ultrahigh density of opticalstates in an exceptionally small mode volume. Here we compress
the mode volume by squeezing light fields into a super narrownano-gap between a gold nanocube and a metallic substrate,
which comprise a novel plasmonic nanocube-film cavity. We
experimentally demonstrate the strong coupling between
molecular excitons and plasmonic resonances (so-called
plexcitonic coupling) in such a cavity, which can induce profoundand significant spectral and spatial modification to the plasmonicgap modes. Within the spectral span of a single gap mode ina nanotube-film cavity with a 3-nm wide gap, the introductionof narrowband J-aggregate dye molecules enables an anticrossing behaviour in the spectral response, splitting the single
mode into two distinct spatial modes that are easily identified bytheir far-field scattering profiles. Simulation results confirm theexperimental findings. Our work not only provides us significant
insights into the nature of coherent light-matter interaction, butalso contributes to the nanophotonic quantum electrodynamics
applications, e.g. reshaping radiative properties of plasmonic
cavities and effectively enhancing interaction with single emitters.

10028-47, Session 5

Electrically-driven plasmonic nanorod
metamaterials
Pan Wang, Alexey V. Krasavin, Mazhar E. Nasir, Wayne
Dickson, Anatoly V. Zayats, King’s College London (United
Kingdom)
Typically, surface plasmons in metal nanostructures are excitedby external illumination. Low-energy inelastic tunneling electron(few eV) is an alternative way to excite surface plasmons with224

SPIE Photonics Asia·

high compactness. However, the difficulty in fabrication ofrequired tunneling gaps (~1 nm) in metal nanostructures hinders
the practical applications. Here, by taking advantage of thehigh-density gold nanorods, we demonstrated a facile method
for electric stimulation of plasmonic excitations and related lightemission in metamaterials using inelastic electron tunneling.
To form tunneling gaps, a plasmonic nanorod metamaterial was
first ion-milled to achieve the gold nanorods ~1 nm shorter thansurrounding alumina matrix. Then, a droplet of eutectic gallium
and indium (EGaIn) was added onto the sample surface working
as an upper electrode, forming approximately 1010 of ~1-nm air
gaps between the nanorod tips and the EGaIn electrode. Whena low voltage was applied between the gold nanorods and the
EGaIn, strong light emission was observed from the substrateside of the sample. The effect is due to the excitation plasmonicmodes of individual nanorods that subsequently couple to themodes of the nanorod metamaterial, which in turn is converted
to free-space photons at substrate side. The measured spectra of
the emitted light obtained under different bias voltages show theintensity increase of the emitted light along with the blue shiftof the high frequency cutoff with the increased applied voltage,
covering hyperbolic dispersion range of the metamaterial.
The observed effect provides new opportunity for designingelectrically driven integrated light sources for metamaterialbased biochemical sensors as well as integrated nanophotonic
applications.

10028-27, Session 6

Quantum optics with graphene plasmons(Invited Paper)
Javier García de Abajo, ICFO - Institut de CiènciesFotòniques (Spain)
Plasmons in highly doped graphene are extremely tunable byexternal means (electrically, thermally, magnetically, nonlinearly)
and exhibit record levels of confinement. Consequently, theinteraction with optical quantum emitters is extraordinarily
intense, rendering these excitations an excellent platform for the
implementation of quantum optics phenomena at the nanometerscale. In particular, the strong-coupling regime is expected tobe reached at the single plasmon level. In this presentation, we
will discuss the physics and phenomenology of quantum optics
phenomena enabled by graphene plasmons, as well as theirapplication in light modulation at the nanoscale.

10028-28, Session 6

Plasmonic detour phase meta-hologram
Changjun Min, Ting Lei, Zhenwei Xie, Xiaocong Yuan,
Shenzhen Univ. (China)
As a powerful optical device for manipulating phase andamplitude of light, detour-phase hologram has widely been
employed in applications of beam shaping, three-dimensional
display, optical signal processing, and others. However, traditional
detour phase hologram is not sensitive to the polarizationof light, and thus it cannot shape the polarization status oflight or work as polarization-multiplexing devices. Thus, toimprove the performance of traditional detour phase hologram,
especially in polarization response, we introduce the lightmetasurface interaction mechanism to the traditional detourphase hologram, and design a novel polarization selective detourphase meta-hologram assisted by plasmonic nano-slits, whichshows attractive advantages of polarization multiplexing ability,
broadband response, and ultra-compact size. The meta-hologram
relies on the dislocations of plasmonic slits to achieve arbitrary
phase distributions, showing strong polarization selectivity
to incident light due to the plasmonic response of deep-

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Conference 10028: Plasmonics II

subwavelength slits. To verify the polarization selectivity andbroadband responses, we demonstrate two holographic patternsof an optical vortex and an Airy beam at p- and s-polarized lightwith wavelengths of 532nm, 633nm and 780nm, respectively, byboth experiments and FDTD calculations. In addition, we realize
an application example of the meta-hologram for generating two
3 x 3 OAM arrays for p- and s-polarizations, respectively, anddetecting the incident OAMs, to further demonstrate its great
potential as a photonic device for OAM generation, detection andmodulation. Such plasmonic detour phase meta-hologram could
find applications in a wide field of photonics, such as chip-level
beam shaping and high-capacity OAM communication.

10028-29, Session 6

Coherent control of plasmonic spin-halleffectShiyi Xiao, The Univ. of Birmingham (United Kingdom);
Fan Zhong, Hui Liu, Shining Zhu, Nanjing Univ. (China);
Jensen Li, The Univ. of Birmingham (United Kingdom)
In recent years, many attentions have been paid to the spin-orbit
interaction (SOI) of light using geometric-phase enabled opticaland plasmonic systems. Together with the recent developmentsof metasurfaces, it offers an alternative route to excite SPPs
through SOI with opposite geometric phases for the two spins.
The associated spin-dependent phenomena can be regarded as
the optical spin-Hall effect (OSHE). However, the time-reversely
related SPP profiles, from the opposite geometric phases,
generated with the two normal incident spins in these cases haveso far only demonstrated simple and symmetric splitting of thetwo spins, known as optical spin Hall effect. Without a proper
geometric phase design scheme, the generated SPP profiles arefar from arbitrary and independent for the two spins. It refrains us
to fully exploit the potential of OSHE and to allow the two spins
to work cooperatively in a flexible manner. Here we demonstratecoherent and independent control of SPP orbitals for the two
opposite spins using multiple rings of nano-slots with properly
designed orientations on a metasurface. This scheme provides us
to achieve arbitrary optical spin-Hall effect. We demonstrate thetwo opposite spins can cooperate with each other. Such coherent
control can further provide us the capability to assemble a series
of individually designed “time” frames as a motion picture being
played back by rotating the linear polarization of the incident
light. This is a form of spin-enabled coherent control and provides
a unique way in achieving tunable orbital motions in plasmonics.

10028-30, Session 6

Ultrafast on-chip all-optical switch inintegrated photonic circuits
Zhen Chai, Xiaoyong Hu, Yu Zhu, Xiaoyu Yang, Feifan
Wang, Zibo Gong, Hong Yang, Qihuang Gong, Peking
Univ. (China)
Ultrafast on-chip all-optical switch is an essential component of
ultrahigh-speed information processing chips. Several significant
indexes are stringently required, i.e. on-chip trigger, ultralowenergy consumption, and wideband (or multiple-wavelength)
operation. To date, such an all-optical switch has not been
demonstrated due to intrinsic bottleneck limitations of materials.
Here, we report, for the first time, a picosecond and lowpower all-optical switch with multiple operating wavelengths
in integrated photonic circuits, on-chip-triggered by a control
light. The sample configuration combines the advantages ofplasmonics and photonics, i.e. plasmonic nanostructures used
as core units interconnected by ultralow-loss dielectric slot
waveguides. A large nonlinearity enhancement is obtained basedon resonant excitation, local field effect, and field enhancement

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effect, while fast response is maintained by intermolecular energy
transfer. A fast response of 63 ps and ultralow control lightintensity of 450 kW/cm2 are achieved.

10028-31, Session 6

Coupling of single quantum dot and aplasmonic nanowire (Invited Paper)Hong Wei, Institute of Physics (China)
The interactions between surface plasmons (SPs) and excitonsin the coupled systems of metal nanostructures and quantum
emitters (QEs) lead to many interesting phenomena and potential
applications, which are strongly dependent on the efficiency of
excitons converting to SPs, i.e., the quantum yield of SPs. As is
known, there are three channels for the recombination of theexcitons in coupled plasmonic systems, which are the direct freespace radiation channel, SP generation channel and nonradiative
damping channel. The difficulty in distinguishing all the possible
exciton recombination channels hinders the experimental
determination of SP quantum yield.
The propagating SPs supported by the metal nanowire (NW)
make it possible to separate the directly radiative photons
and the generated SPs in the QE-NW coupling structure,
which provides a suitable system to disentangle the exciton
recombination channels and obtain the SP quantum yield. Here,
we carefully analyzed the exciton-plasmon coupling process inthe coupled system of a single quantum dot (QD) and a silver
NW. The quantum yield of single SP generation is experimentally
determined for the first time by disentangling all the exciton
recombination channels. Moreover, we used Al2O3 film ofdifferent thickness to control the QD-NW separation and studied
the distance-dependent exciton recombination dynamics. Our
results show that the optimum QD-NW coupling distance forthe largest SP quantum yield is about 10 nm, resulting from thedifferent distance-dependent decay rates of the three channels.

10028-32, Session 6

Plasmonic interference for classical andquantum logical gates (Invited Paper)
Tao Li, Shuming Wang, Yulin Wang, Shining Zhu, Nanjing
Univ. (China)
Plasmonic has provided versatile solutions to confine the light at
sub-wavelength scale together with strong field enhancement,
which enables great possibilities for compact photonic
integration and other applications. In this talk, I would firstly
show an interesting composite plasmonic interference resulted
from two crossed strip-metallic waveguides with a narrower
gap, where the vectorial field configuration gives rise to twoquite different interferences (synchronous and antisynchronous).
Based on this interference effects, compact SPP switches areproposed and demonstrated with respect to external phasemodulations [1]. These plasmonic switches under different
phase conditions are found to work as photonic logical gatesfor some specific functionality. Secondly, in a further step,classical plasmonic interference is extended to quantum regime.
By coupling the entangled photons into the plasmonic system,
quantum plasmonic interference has been revealed in single
plasmon level [2,3]. Nevertheless, here, I would like to report
the first realization of a plasmonic Control-NOT gate for two
polarization-entangled plasmonic qubits based on the metal/
dielectric hybrid waveguide, which is the very fundamental blockfor integrated quantum processing. This device is implemented
by a polarization sensitive beam splitter that is formed by aproper grating in the hybrid waveguide. It enables an R/T ratio of
2/1 for the TM wave (SPP) while direct transmission for TE wave,
which satisfies the requirement of the CNOT gate. Finally, we#PhotonicsAsia

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Conference 10028: Plasmonics IIrealize, to our knowledge, the smallest CNOT gate (14*14 micro)with an estimated fidelity of 63.7%< F<80.3% [4]. This result
demonstrates the validation of plasmonic system to quantum
information science and technology.

10028-33, Session 710028-35, Session 7

Circular dichroism and plasmonic
properties of noble metal assemblies(Invited Paper)
Chuanlai Xu, Liguang Xu, Xiaoling Wu, Hua Kuang,
Jiangnan Univ. (China)

Deep UV plasmonics and Raman
microscopy (Invited Paper)
Satoshi Kawata, Osaka Univ. (Japan)
Recent development of deep UV light sources opens a new worldof nanophotonics, as exemplified by deep UV photo-lithography,
photo-catalysis, sterilization, and molecular-sensing, analysis andimaging. If deep UV optics is combined with Raman scattering
microscopy, the distribution of nucleotides and proteins in a cellis imaged and analyzed without labelling. However, the use ofdeep UV light for bio-imaging is limited because it can destroy ordenature target bio-molecules. Recently, we proposed a method
for suppressing the photo-degradation of molecules usinglanthanide ions in solution as energy quenchers [1]. This approachdirectly removes excited energy at the fundamental origin ofcellular photo-degradation. For sub-wavelength imaging, weneed a plasmonic tip, which works in deep UV to enhance Raman
scattering at molecules. We have found that aluminum is one of
the best metals that exhibit plasmonic field enhancement effectin deep-UV, while not in visible because the imaginary part of thedielectric constant for aluminum is very large in the visible range[2]. We also found that Indium is another good candidate indeep UV and is useful in practice for vapor deposition due to therelatively low meting point [3], which is important for producing
multi-grain tips for highly reproducible enhancement [4].
[1] Y. Kumamoto,et.al., Biomed. Opt. Express, 7, 158 (2016).
[2] A. Taguchi, et. al, J. Raman Spectrosc. 40, 1324, (2009).
[3] Y. Kumamoto, et. al, ACS Photon. 1, 598 (2014).

Chiral nanoscale photonic systems typically follow either
tetrahedral or helical geometries that require four or moredifferent constituent nanoparticles. Smaller number of particles
and different chiral geometries taking advantage of theself-organization capabilities of nanomaterials will advanceunderstanding of chiral plasmonic effects, facilitate developmentof their theory, and stimulate practical applications ofchiroplasmonics. Here we show that gold nanorods self-assemble
into side-by-side orientated pairs and ‘‘ladders’’ in which chiralproperties originate from the small dihedral angle between them.
Spontaneous twisting of one nanorod versus the other one
breaks the centrosymmetric nature of the parallel assemblies.
Two possible enantiomeric conformations with positive andnegative dihedral angles were obtained with different assembly
triggers. The chiral nature of the angled nanorod pairs was
confirmed by 4p full space simulations and the first example ofsingle-particle CD spectroscopy. Self-assembled nanorod pairsand ‘‘ladders’’ enable the development of chiral metamaterials,(bio)sensors, and new catalytic processes. Similarly, heterodimersof Au NPs were fabricated with DNA or NaCl respectively.Taking
into account that the shapes of the NPs are nonspherical, chiralproperties of heterodimers were attributed to the cooperative
effect of the small dihedral angle between two adjacent NPs andthe plasmonic coupling of NPs, which break the symmetric natureof two uniform spheres; this conclusion was confirmed by 4π
full space simulation. Impressively, the chiroptical response wastunable and reversible, and it was achieved by changing the sizeof building blocks and the temperature.

[4] A. Taguchi,et. al, Nano Scale, 7, 17424 (2015).

10028-36, Session 710028-34, Session 7

Unidirectional antenna by spoof-localized
surface plasmon resonators
FeiFei Qin, Jun-Jun Xiao, Harbin Institute of Technology
Shenzhen Graduate School (China)
We propose a deep sub-wavelength unidirectional antenna that isrealized by spoof localized surface plasmon resonators (SLSPR).
This kind of resonator can support both magnetic dipole modes
and electric dipole modes and derive their properties fromstructural resonance rather than from the electronic resonance[1]. By carefully adjusting the geometry of the composite
structures, the magnetic and electric dipole resonances canoverlap spectrally. With that, strong directional light scatteringin the forward direction, which can act as a directive RF antenna
with nearly zero backscattered fieldcan be achieved. Suchbehavior is similar to the Kerker’s scattering by hypothetic
magneto-dielectric particles [2] and provides different platform
for engineering directional antenna in microwave or THz bands.
References
1. P. A. Huidobro, X. Shen, J. Cuerda, E. Moreno, L. Martin-Moreno,
F. J. Garcia-Vidal, and J. B. Pendry, Phys. Rev. X , 4, 021003(2014).
2. M. Kerker, D.-S. Wang, and C. L. Giles, J. Opt. Soc. Am. 73, 765(1983).

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A high-Q plasmonic-photonic hybrid mode
(Invited Paper)
Yun-Feng Xiao, Peking Univ. (China)
Localized-surface plasmonic resonances (LSPRs) supported bymetal nanoparticles (MNP) enable subwavelength confinementof light, forming an ideal bridge between light and matter.
However the Ohmic loss intrinsic to metal limits the life time ofplasmon and leads to quenching phenomena. Such undesirable
effects are successfully inhibited by introducing an optical cavity
and forming a high-Q plasmonic-photonic hybrid mode, which
possesses both small mode volume of plasmonic resonators andlong life time of photonic resonators. We analytically study theinteraction of LSPRs with the microcavity and demonstrate thatthe property of the hybrid mode can be easily tuned, showing
great advantages in various applications. Particularly, we focus
on the interaction of such a plasmonic-photonic mode with aquantum emitter, such as atom, molecular, quantum dot, etc.
In this composite system, the microcavity serves as a low-loss
storage of the optical field, while the MNP plays the role of an
optical antenna which creates a hot spot and magnifies the local
optical field. Therefore, the cooperativity parameter between
the cavity mode and emitter achieves a more than 100-foldincrease, compared with bare cavity. In addition, quantum yieldis enhanced by an order of magnitude compared with care MNP.
It is achieved by forming a low-loss dark state in this system,
which consists of cavity mode and emitter while bypassing thelossy MNP. With the greatly improved cooperativity parameterand quantum yield, we claim that the high-Q plasmonic-photonic
hybrid mode holds potential for highly sensitive sensing andprecise quantum manipulation.

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Conference 10029: Quantum and Nonlinear Optics IV
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10029 Quantum and Nonlinear Optics IV

10029-1, Session 1

Temporal purity and Hong-Ou-Mandel
quantum interference of single photons
from two independent cold atomic
ensembles (Invited Paper)
Jiefei Chen, East China Normal Univ. (China); Weiping
Zhang, Shanghai Jiao Tong Univ. (China)
The temporal purity of the single photons is crucial to theindistinguishability of independent photon sources for
fundamental study of quantum nature of light and to thedevelopment of the photonic technologies. Currently thetechnique for single photons heralded from time-frequency
entangled biphotons created in nonlinear crystals doesn’t
guarantee the temporal quantum purity, except using spectral
filtering. Nevertheless, an entirely different situation is anticipatedfor narrow-band biphotons with a coherence time far longer
than the time-resolution of single photon detector. Here wedemonstrate temporally pure single photons with coherence timeof 100 ns, directly heralded from the time-frequency entangled
biphotons generated by spontaneous four-wave mixing in cold
atomic ensembles, without any supplemented filters or cavities.
A near-perfect purity and indistinguishability are both verified
through the Hong-Ou-Mandel quantum interference using single
photons from two independent cold atomic ensembles without
synchronization.

10029-2, Session 1

Farfield superlocalization of two close
incoherent sources via linear optics(Invited Paper)
Ranjith Nair, Xiao-Ming Lu, Shan Zheng Ang, Mankei
Tsang, National Univ. of Singapore (Singapore)
Rayleigh’s criterion for resolving two incoherent point sources
has been the most influential measure of farfield optical imaging
resolution for over a century. In the context of statistical image
processing, violation of the criterion is especially detrimental
to the estimation of the separation between the sources,
and modern superresolution techniques rely on suppressing
the emission of close sources to enhance the localization
precision. Using quantum optics, quantum information theory,and statistical analysis, here we show that, even if two close
incoherent sources emit simultaneously, measurements withlinear optics and photon counting can estimate their separation
almost as precisely as conventional methods do for isolated
sources, rendering Rayleigh’s criterion irrelevant to the problem.
Our results demonstrate that superresolution can be achieved not
only for fluorophores but also for stars.

10029-3, Session 1

Multiplexed entangled photon sources for
all fiber quantum networks
Zhiyuan Zhou, Bao-Sen Shi, Univ. of Science andTechnology of China (China)
The ultimate goal of quantum information science is to build aglobal quantum network, which enables quantum resources to be
distributed and shared between remote parties. Such quantum
network can be realized by all fiber elements, which takes
advantage of low transmission loss?low cost, scalable and mutual

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fiber communication techniques such as dense wavelength
division multiplexing (DWDM). Therefore high quality entangled
photon sources based on fibers are on demanding for building
up such kind of quantum network. Here we report multiplexed
polarization and time-bin entanglement photon sources basedon dispersion shifted fiber (DSF) operating at room temperature.
High qualities of entanglement are characterized by using
interference, Bell inequality and quantum state tomography.
Simultaneous presence of entanglements in multi-channel pairsof a 100GHz DWDM shows the great capacity for entanglements
distribution over multi-users. Our research provides a versatile
platform and moves a first step toward constructing an all fiber
quantum network.
Though there are many works reported on preparing entangled
photon source based on DSF, no one reported wavelength
multiplexed entangled source based on DSF, which has thesame figure of merits suc as: realizing entanglement over multifrequency modes, which enable engineering a complex quantum
state; compatible with contemporary telecom fiber and quantum
memories, and with chip-scale semi-conductor technology, whichis capable for compact, low cost and scalable applications.

10029-4, Session 1

Quadrature squeezed state preparation for
quantum remote sensing at 1064nm
Zhiqiang Wu, Xuling Lin, Song Yang, Xuan Zhang, Beijing
Institute of Space Mechanics and Electricity (China);
Yaohui Zheng, Shanxi Univ. (China)
Squeezed state light field can surpass the shot noise limit andimprove the signal-to-noise ratio of the sensor measurement.
We present employs a semi-monolithic cavity to reduce theintra-cavity loss of optical parametric amplifier (OPA) andminiaturization design to improve system stability. In this paper,
the bright quadrature squeezed state field of noise reduces
more than 6dB is obtained at 1064nm by pumped the PPKTP
crystal via 532nm laser with the power of 130mW. The light fieldcharacteristics of the quantum state source are analyzed. This
work provides a foundation for further application in quantum
remote sensing detection.

10029-6, Session 2

Non-equilibrium quantum phase transition
via entanglement decoherence dynamics
in photonic systems (Invited Paper)
Wei-Min Zhang, Yu-Chen Lin, Pei-Yun Yang, National
Cheng Kung Univ. (Taiwan)
We investigate the decoherence dynamics of continuous variableentanglement in photonic systems as the system-environment
coupling strength varies from the weak-coupling to the strongcoupling regimes. Due to the existence of localized statesin the strong-coupling regime, the system cannot approach
equilibrium with its environment, and a nonequilibrium quantum
phase transition occurs. We analytically solve the entanglement
decoherence dynamics for arbitrary spectral density. The
nonequilibrium quantum phase transition is demonstrated as
the system-environment coupling strength varies for all the
Ohmic-type spectral densities. The entanglement quantum phase
diagram is obtained.

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Conference 10029: Quantum and Nonlinear Optics IV

10029-7, Session 2

From Einstein-Podolsky-Rosen paradox toquantum nonlocality (Invited Paper)
Jin-Shi Xu, Chuan-Feng Li, Guang-Can Guo, Univ. of
Science and Technology of China (China)
In 1935, Einstein, Podolsky and Rosen published their influential
paper proposing a now famous paradox (the EPR paradox)that threw doubt on the completeness of quantum mechanics.
Two fundamental concepts “entanglement” and “steering” were
given in the response of Schrödinger to the EPR paper, which
both reflect the nonlocal nature of quantum mechanics. In 1964,
John Bell obtained an experimentally testable inequality (Bell’sinequality), in which its violation contradicts the prediction of
local hidden variable models and agrees with that of quantum
mechanics. Since then, great efforts have been made toinvestigate the nonlocal feature of quantum mechanics andmany distinguished quantum properties were observed. In 2001,
quantum correlation was shown to even exist in separated states(have not entanglement) and the total quantum correlation isdefined as quantum discord. In 2007, an operational approach
was used to define entanglement, EPR steering and Bellnonlocality. It is shown that EPR steering strictly stands between
entanglement and Bell nonlocality. In this report, along withthe discussion of the development of quantum nonlocality, we
would focus on our recent experimental efforts in investigating
the corresponding distinguished quantum properties in opticalsystems, including the sudden death of quantum entanglement,
entanglement-assisted entropic uncertainty principle, the suddenchange in behavior in the decay rates of quantum discord, the
All-Versus-Nothing demonstration of EPR steering and the oneway EPR steering.

10029-8, Session 2

On-chip quantum optics with quantum
dots and superconducting resonators(Invited Paper)
Guang-Wei Deng, Univ. of Science and Technology ofChina (China)
Hybrid systems that couple nano-devices to microwave
resonators have rapidly been developing with recent advancesin circuit quantum electrodynamics. In our first work, wedemonstrated a successful coupling between an on-chipsuperconductor resonator and a graphene double quantum
dot. We are very proud of our accomplishment as the coupling
between cavity and randomly located graphene flakes is atechnical challenge. A number of technical innovations, including
cavity design and nano-fabrications, are made to create such a
hybrid nanostructure. Using the resonator as a sensitive meter,
we are able to measure the dephasing rate of graphene qubit,
which has not been achieved by conventional means up to
now. In the second work, we have demonstrated for the firsttime a successful coupling between an on-chip superconductor
resonator and two double quantum dots made of graphene. Thiskind of coupling can be explained by the Tavis-Cummings model.
Such model has been explored in a number of systems, suchas optics and superconducting qubits. However, it has not yet
been demonstrated in gate-defined quantum-dot hybrid devices.
Another significant finding of our work is the achievement of thenonlocal transport current through two distant DQDs, the current
cross-noise spectrum is measured for the first time, which can be
mediated by the photons in the resonator. This nonlocal transportobserved here may serve as one step toward entangling
distant electrons and employing superconducting resonators
as microwave photonic buses.In addition, this hybrid systemdemonstrates the possibility to exploit the microwave photonic
bus to link different nano-electronic devices as it becomes

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increasingly apparent that future integrated circuits may consistof both electronic and optical devices.

10029-9, Session 2

Quantum-enhanced long-baseline opticalinterferometers with noiseless linear
amplification and displacement operation
Song Yang, Yun Su, Ningjuan Ruan, Zhiqiang Wu, Xuling
Lin, Beijing Institute of Space Mechanics and Electricity(China)For an optical imaging system- a telescope or camera, diffraction
limit has been considered as a fundamental maximum to its
resolution. According to diffraction limit, the resolution of a single
telescope with circular aperture is proportional to the diameterof its aperture D , and inversely proportional to the wavelength? of the incoming light. In astronomy, a single telescope always
cannot satisfy some needs of high resolution imaging application,
since the size of a telescope cannot increase boundlessly.
In the past few decades, advances in the optical interferometry
enable us to sidestep the diffraction limit of a single telescope.
The optical interferometry could achieve high resolution due
to the technique of aperture synthesis, collecting signals froma cluster of comparatively small telescopes. The resolution ofinterferometry is limited by? / 2b , which is proportional to the
maximum separation(i.e. baseline) b between the telescopes.
Thus, long baseline would enhance the imaging resolution.
In some sense, the optical interferometry with a cluster oftelescopes canbe equivalent to an expensive monolithic
telescope with a very large aperture size b . In astronomy, thehigh imaging resolution of long baseline optical interferometry
paves the way for its promising applications in some new fields
like imaging stellar surfaces and exploring stellar evolution.
However, the astronomical observations from Earth are seeinglimited due to atmospheric effects. The noise and photon loss
in the transmission between the telescopes would limit thelength of baseline of interferometer to a few hundred meters.
Here, we present a scheme for enhancement of long baseline
optical interferometer by using quantum resources- noiselesslinear amplifier (NLA) and displacement operation at thephoton transmission channels. We exhibit this enhancement
quantitatively by calculating higher fisher information comparedwith those of conventional optical interferometer.

10029-10, Session 2

Demonstration of a triggered singlephoton source based on a trapped single
cesium atom
Jun He, Bei Liu, Gang Jin, Junmin Wang, Shanxi Univ.
(China)We report the generation of a 10-MHz-repetition-rate triggered
single-photon source at 852 nm based on a trapped single
cesium atom in a far-off-resonance microscopic optical dipole
trap. The statistics show strong anti-bunching with a value forthe second-order correlation at zero delay less than 0.09, whichindicates single-photon characters. The optical dipole trap beam
is focused by a high numerical aperture (NA = 0.29) objective
lens assembly mounted outside the vacuum chamber. thetrapping beam has a 1/e2 radius of ?0 = 2.3 ?m. The trap depth
is about 2 mK for a laser power about 63 mW. The P7888 card
(two-input multiple-event time digitizers, FAST Com Tech.) is
used to record the arrival times of atomic fluorescence detectedby the SPCM. With an optimized time sequence, we haveexperimentally demonstrated the Rabi oscillation between the

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Conference 10029: Quantum and Nonlinear Optics IV

ground state and the excited state, and measured the temporalenvelope of single photons. We have experimentally verified theheating of the single atom by using of a gated pulses exciting/cooling technique and optimized cooling laser’s parameters.
In case of resonant light pulse excitation, the typical trapping
lifetime of single cesium atom is extended from ~56 ms to~2536 ms. The corresponding number of excitation is improved
from 1600 to 72000. In the future, we will encode the orbital
angular moment on single photon with the help of spatial light
modulation, which provides a promising resource for highdimensional quantum information protocols. We will study theinteraction between the neutral atom and single photon.

10029-11, Session 2

Traceable quantum sensing and metrology
relied up a quantum electrical triangle
principle
Yan Fang M.D., Fudan Univ. (China)
Hybrid quantum state engineering in quantum communicationand imaging1-2 needs traceable quantum sensing and metrology,
which are especially critical to quantum internet3 and precision
measurements4 that are important across all field of science andtechnology-. We aim to set up a mode of traceable quantum
sensing and metrology. We developed a method by speciallytransforming an atomic force microscopy (AFM) and a scanningtunneling microscopy (STM) into a conducting atomic force
microscopy (C-AFM) with a feedback control loop, whereinquantum entanglement enabling higher precision was relied upona set-point, a visible light laser beam-controlled an interferometerwith a surface standard at z axis, diffractometers with lateralstandards at x-y axes, four-quadrant photodiode detectors, ascanner and its image software, a phase-locked pre-amplifier,a cantilever with a kHz Pt/Au conducting tip, a double barrier
tunneling junction model, a STM circuit by frequency modulation
and a quantum electrical triangle principle involving single
electron tunneling effect, quantum Hall effect and Josephson
effect5. The average and standard deviation result of repeatedmeasurements on a 1 nm height micro-region of nanomedicine
cystal hybrid qauntum state engineering surface and its local
differential pA level current and voltage (dI/dV) in time domains
by using C-AFM was converted into an international systemof units: Siemens (S), an indicated value 0.38?10-12 S (n=6)
of a relative standard uncertainty was superior over a relative
standard uncertainty reference value 2.3?10-10 S of 2012
CODADA quantized conductance6. It is concluded that traceable
quantum sensing and metrology is emerging.

10029-59, Session 2

A doubly folded quantum security scheme
for a nearly perfect direct quantum
communication protocol (Invited Paper)
Jihong Min, Byoung S. Ham, Gwangju Institute of Scienceand Technology (Korea, Republic of)
Sharing a secure key between two remotely separated parties
has been an important issue in communications to human history.
According to Heisenberg’s uncertainty principle, simultaneous
measurements on both conjugate variables (e.g., position andmomentum) in an unknown quantum state are impossible. This
physical limitation is the basis of the ‘no cloning’ theorem inquantum information, and applied to the unconditional security
in quantum communications. Here, quantum key distribution(QKD) techniques such as BB84 and E91 adapt the conjugate
variables to conjugate bases for unconditional security. In BB84,
for example, a set of linearly polarized light perpendicular to each

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Follow us on:other forms a basis. A rotation by 45 degrees of this basis withrespect to one polarization forms another basis. These two bases
satisfy the conjugate variables in the Heisenberg’s uncertainty
principle, where measurement by one basis results in a complete
random output to the other basis. Here we propose a doubly
folded quantum security scheme for a nearly perfect quantum
secure direct communications (QSDC) based on polarized single
photons. Unlike QKD, the QSDC techniques encode and decode amessage directly without key distribution. Thus, perfect security
must be an essential part to protect message itself from any
chance of eavesdropping. Most QSDC protocols, thus, rely on
quantum entanglement rather than photon polarizations, where
single photons have shown many loopholes to noisy channels
and imperfect detectors. However, entanglement based schemes
have more difficulties in implementations compared with thepolarized single photons. Our QSDC protocol uses not only
polarizations but also phases of single photons to form two setsof conjugate variables. The addition of phase basis to polarizationbasis forms a nearly perfect security even to super attackers who
can measure unknown quantum states or the sender’s choice ofbases.

10029-12, Session 3

Detecting high-dimensional multipartite
entanglement via some classes ofmeasurements (Invited Paper)
Ting Gao, Hebei Normal Univ. (China)
Mutually unbiased bases (MUBs) represent maximally noncommutative measurements, which means the state of a systemdescribed in one mutually unbiased base (MUB) provided
no information about the state in another. Many quantum
information protocols depend upon the use of MUBs, suchas quantum key distribution, the reconstruction of quantum
states, etc. The concept of MUBs was generalized to mutually
unbiased measurements (MUMs) due to the open problem of
the maximum number of MUBs for non-prime power dimensions
limits its application. The construction of a complete set of $d+1$
MUMs were found in a finite, $d$-dimensional Hilbert space, nomatter whether $d$ is a prime power. Symmetric informationallycomplete positive operator-valued measures (SIC-POVMs)
is another related topic in quantum information, which has
many helpful connections with MUBs, such as operational link,quantum state tomography and uncertainty relations. Since it
has some similar limitation as MUBs, the concept of SIC-POVMs
is generalized to general symmetric informationally complete
measurements (GSIC-POVMs), which were constructed without
requiring to be rank one.
These quantum measurements have been used to detectentanglement recently. We investigate entanglement detection
using these notions and derive separability criteria for arbitraryhigh-dimensional bipartite systems of a $d_1$-dimensional
subsystem and a $d_2$-dimensional subsystem, and multipartite
systems of $m$ multi-level subsystems. It is proved thatthese criteria are of the advantages of more effective andwider application range than the previous ones. They provide
experimental implementation in detecting entanglement of
unknown quantum states.

10029-13, Session 3

How discord underlies the noise resilienceof quantum illumination (Invited Paper)
Mile Gu, Ctr. for Quantum Technologies (Singapore)
Quantum illumination offers a radical departure fromconventional quantum protocols. Most quantum technologies
require fragile entangling correlations to be preserved,#PhotonicsAsia

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Conference 10029: Quantum and Nonlinear Optics IV

whereas quantum illumination operates in extremely-adverse
environments with entanglement-breaking noise. Specifically,
quantum illumination aims to detect a low reflective target
basked in bright noise by probing it with one arm of an entangledstate. The protocol demonstrates significant improvement overthe use of conventional probes, even though the environmental
noise destroys all initial entanglement. This appeared paradoxical,
how can the benefits of entanglement outlast entanglement
itself? In this presentation, I will first review quantum discord, aform of quantum correlations that exist beyond entanglement.
While discord has been conjectured to have operation benefits,
it remains a topic of significant debate. A significant rationale
being that discord is non-zero for almost every mixed stateand its practical merit conflicts with the preconceptionthat `quantum’ effects are fragile. I will then show that it isprecisely the resilience of discord that explains the resilience ofquantum illumination and highlight discord’s role in preserving
entanglement’s benefits in quantum illumination.
References:- “Observing the operational significance of discord
consumption.” Nature Physics 8, 671–675- “How discord underlies the noise-resilience of quantum
illumination.” New Journal of Physics 18 043027- “Quantum technology: The Golden Apple.” Nature Physics 10,47410029-14, Session 3

Quantum information tapping using afiber optical parametric amplifier withnoise figure improved by correlated inputs(Invited Paper)

Self-assembled InGaAs quantum dots (QD) are promising singlephoton emitters with high quantum efficiency and fast decayrate. In the past decades, extensive efforts have been devoted to
producing single photons with high purity (that is, vanishing twophoton emission probability), near-unity indistinguishability [1],and high extraction efficiency. These key properties have been
compatibly combined simultaneously on the same QD-micropillar
very recently [2,3].
An important next challenge is to extend the single-photon
sources to multiple photonic quantum bits [4], as required byvarious quantum information protocols such as boson sampling,
quantum teleportation [5], and quantum computation. To
this end, by pulsed s-shell resonant excitation of a single QDmicropillar, we generate long streams of thousands of single
photons with high indistinguishability [6]. Interference of two
photons are measured as a function of their emission time
separation varying from 13 ns to 14.7 us, where the visibility
slightly drops from 95.9% to a plateau of 91.8% through a slow
dephasing process occurring at time scale of 0.7 us. Such an
efficient and highly indistinguishable single-photon source
allowed scalable multi-photon Boson sampling experiments [7]with a performance beating the best conventional nonlinear
optics. The single photons are time-bin encoded and interfered inan electrically programmable loop-based network. With further
refinement of the system efficiency, our approach may be feasible
to be scaled up to ? 20-boson sampling to outperform classicalcomputers, and thus provide experimental evidence against the
Extended Church-Turing Thesis.
[1] Y.-M. He et al. On-demand semiconductor singlephoton source with near-unity indistinguishability Nature
Nanotechnology 8, 213 (2013).
[2] X. Ding et al. On-Demand Single Photons with High Extraction
Efficiency and Near-Unity Indistinguishability from a Resonan tly
Driven Quantum Dot in a Micropillar, Phys. Rev. Lett. 116, 020401(2016).

Xiaoying Li, Tianjin Univ. (China)[3] S. Unsleber et al. http://arxiv.org/abs/1512.07453 (2015).

In a network, information distribution requires information
tapping. The easiest and usual way to do so is to tap the signal
by using a beam splitter (BS). However, in this case, the signal
to noise ratio (SNR) of the tapped signal is lower than that of
the input signal. Because of the vacuum noise introduced fromthe unused port of the BS, the sum of the information transfer
coefficient in the each output port of the beam splitter is lessthan 1 (classical limit). In order to read out information without
degrading the SNR, the extra noise added in the information
distribution process need to be minimized.

[5] X.-L. Wang et al. Quantum teleportation of multiple degrees
of freedom of a single photon, Nature 518, 516 (2015).

[4] J.-W. Pan et al. Rev. Mod. Phys 84, 777 (2012).

[6] H. Wang et al. arXiv:1602.07386[7] Y. He et al. arXiv:1603.04127

10029-16, Session 4

In this talk, we experimentally demonstrate a quantum
information tap by using a fiber optical parametric amplifier(FOPA) with correlated inputs, whose noise is reduced by
the destructive quantum interference through quantum
entanglement between the signal and the idler input fields. We
find that the noise figure (NF) of the FOPA with correlated inputs
is better than that of a regular FOPA with one unused input
port. Since the NF is inversely proportional to the corresponding
information transfer coefficient, therefore, our experimental
system, working at 1550 nm telecom band and compatible
with the current optical fiber network, can act as the quantum
information tap to split the encoded information into the signal
and idler output ports with an overall information transfer
coefficient larger than the classical limit.

10029-15, Session 3

Towards multi-photon experiments withquantum dots (Invited Paper)
Chao-Yang Lu, Univ. of Science and Technology of China(China); Sven Höfling, Julius-Maximilians-Univ. Würzburg(Germany); Jian-Wei Pan, Univ. of Science and Technology
of China (China)
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Experimental quantum secure directcommunication with single photons(Invited Paper)
Gui Lu Long, Tsinghua Univ. (China)
Quantum secure direct communication (QSDC), Quantum secretsharing and quantum key distribution are the major branchesof quantum cryptography. Using QSDC, secret message aresent directly over a quantum channel with security. QSDC offers
higher security and instantaneousness in communication. It
is also a powerful basic quantum communication primitive tobuild other quantum communication protocols such as quantum
bidding, quantum signature and quantum dialogue and so on.
Since the first QSDC protocol proposed in 2000[G L Long and X
S Liu, Phys. Rev. A 65 , 032302 (2002)], it has become one of the
hot research areas. In this invited talk, after a brief introduction to
the basic ideas of QSDC, we will concentrate on the experimental
progress in QSDC, in particular, the experimental demonstrationof the DL04 QSDC protocol in a noisy environment [Jian-Yong
Hu et al, Light: Science & Applications, 2016; doi: 10.1038 /lsa.2016.144.]www.spie.org/pa·

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Conference 10029: Quantum and Nonlinear Optics IV

10029-17, Session 4

Quantum memory with rare-earth ion
doped crystal (Invited Paper)
Chuan-Feng Li, Univ. of Science and Technology of China(China)Quantum memory is the key element of quantum repeater, long
distance quantum communication and quantum network. Usually,
hot atoms, cold atoms, trapped single atom and Bose-Einstein
Condensate have been used as quantum memories. From theyear of 2008, solid state memory based on rare-earth ion doped
crystal becomes one of the most promising quantum memories.
I report on some of our recent results of solid state memory.
1) We realized high-fidelity solid state memory for photonic
polarization qubit. By designing a sandwich-like solid state
memory, we can get photon polarization storage process
fidelity up to 99.9%. 2) We demonstrated solid state memoryof three-dimensional orbital-angular-momentum entanglementwith process fidelity up to 99.3%. We further showed that the
memory is highly reliable for 51 spatial modes. 3) For the firsttime, we further experimentally realized the storage of multiple
single-photon pulses emitted from a quantum dot in solid state
quantum memory. Multi-temporal-mode memory with up to 100
narrow single-photon pulses was demonstrated. The solid-state
properties of both sub-systems make this configuration morestable and easier to be scalable. Our work will be helpful in theconstruction of efficient quantum repeaters based on all-solidstate devices.
We also present the first experimental violation of LeggettGarg type of inequalities with solid state memory. By separately
benchmarking the Markovian character of the evolution andthe translational invariance of the conditional probabilities,
the observed violation is attributed to the quantum coherent
character of the process.

10029-18, Session 4

Entanglement in multimode bosonicsystems (Invited Paper)
Tim Byrnes, New York Univ. Shanghai (China)
We model and examine the quantum states produced between
multi-mode Bose-Einstein condensates. In contrast to standard
approaches which use an exact time evolution and workin the framework of continuous variables (CV), we use theapproximation-free time evolution and obtain the wavefunctionof the ensemble state after the entangling procedure. For shortentangling times, this produces a two-mode squeezed state inagreement with CV based predictions. For longer entangling
times the state evolves into a non-Gaussian form, and the twomode squeezed state characteristics start to diminish. Thesetypes of entangled states are quite difficult to detect using
standard entanglement criteria, which only work in the CV
regime. We propose some alternative entanglement criteria
which can detect these types of entanglement. These criteria canbe used also for other bosonic systems, and potentially give amore sensitive criteria for entanglement.

10029-35, Session Post

Dirac monopoles with polar-core vortex
induced by spin-orbit coupling in spinor
Bose-Einstein condensates

induced by spin-orbit coupling in ferromagnetic Bose-Einsteincondensates, which can be detected through directly imaging
vortex lines. The condensates are subjected to three-dimensional
gradient magnetic field, and two dimensional Rashba-type SO
coupling induced by magnetic pulses. Unlike monopole studies
in spin ices, our results demonstrate the fundamental quantum
features and topological structures of the monopoles predicted
by Dirac. In our case, there exist two Dirac monopoles with thepolar-core vortex, locating at the endpoints of two nodal lines
in the condensates, which behaves as a singly vortex line in thecomponent, a soliton in the component and a singly anti-vortex
line in the component.
When spin-orbit coupling increases, the monopoles with thesquare lattice appear, which behave as the square lattice
structure in the horizontal direction in the central zone of
Bose-Einstein condensates and the stripe structure of density
distribution in the vertical direction. The anti-monopoles emerge
simultaneously.
In the presence of spin-orbit coupling, increasing the strength ofspin-independent interaction can induce a cyclic phase transition
from Dirac monopoles with polar-core vortex to those with
Mermin-Ho vortex.
Our work explores the spin-orbit coupling effect on a new physics
of monopoles, and can not only shed lights on the discovery andillumination of new structures of monopoles, but also provide a
better grasp of fundamental theory on the monopole in nonAbelian gauge fields. Our findings opens a new window to realize
exotic topological defects and phase transitions in quantum
systems.
References:[1] Ji Li, Yan-Mei Yu, Wu-Ming Liu. Spin-orbit coupling induced
Dirac monopoles with polar-core vortex in spinor Bose-Einsteincondensates. arXiv:1602.00189

10029-36, Session Post

Evolution of temporal soliton solution to
the generalized nonlinear Schrödinger
equation with variable coefficients and PTsymmetric potential
Yangbao Deng, Hunan City Univ. (China)
In this paper, the evolution of temporal soliton is investigatedanalytically when the laser pulse propagates in theinhomogeneous nonlinear medium with a Scarff II parity-time(PT)-symmetric potential. Firstly, the temporal soliton solution
is found by analytically solving the generalized nonlinear
Schrödinger equation with variable coefficient and Scarff II PTsymmetric potential. Then the intensity evolution of temporalsoliton is discussed. Finally, the evolution of the pulse width (PW)of temporal soliton is analyzed in detail by calculating secondorder intensity moments. It is find that under the conditionof Scarff II PT-symmetric potential, the dispersion coefficient,nonlinear coefficient and chirp affect the evolution behavior of
temporal soliton. The chirped-free and chirped temporal soliton
are stable when the dispersion coefficient is a periodic modulated
function. So the chirp has no effect on the evolution behaviorof temporal soliton. When the dispersion coefficient are theconstant and the exponential decreasing function, the chirpedfree temporal soliton is stable, while the chirped temporal soliton
is gradually compressed. Therefore, the chirp has a great effecton the evolution behavior of temporal soliton.

Wu-Ming Liu, Ji Li, Institute of Physics (China)
In this work, we report Dirac monopoles with polar-core vortex

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Conference 10029: Quantum and Nonlinear Optics IV

10029-37, Session Post

Generation of polarization squeezing
resonant to the rubidium D1 line at 795 nm
Xin Wen, Yashuai Han, Jun He, Junmin Wang, Shanxi Univ.
(China)Squeezed light has significant potential in quantum physics.
With the noise of one quadrature component reduced below
the standard quantum limit, the squeezed light could be used in
weak field measurements, precise spectroscopy and other fields
in quantum physics with an enhanced signal-to-noise ratio. In
our work, a polarization squeezed light will be used as a probe
light in the precise measurement of magnetic field and inertia forthe reduction of the optical polarization noise, thus increase thedetection sensitivity.
An optical parametric oscillator (OPO) is utilized for thegeneration of the polarization squeezed light. The fundamental
laser is provided by a cw Ti:Sapphire laser tuned to 795nm at
rubidium D1 line. 111mW ultra-violet laser at 397.5nm is achieved
from 191mW fundamental power via a frequency doubling cavity,
the corresponding conversion efficiency is 58.1%. The generated
ultra-violet laser is used to pump the OPO with a PPKTP
nonlinear crystal, the maximum vacuum squeezing of -5.6dB is
realized. With a probe light inject into the OPO cavity, the OPO
works under the condition of optical parametric amplifier, anda dim amplitude/phase squeezed light is produced. Combine
the squeezed light and a bright coherent light with fixed relative
phase, the polarization squeezed light is obtained. The quantum
Stokes parameters are used to depict the polarization squeezing,-3.75dB of the S2 component is accomplished at the analysis
frequency of 2 MHz with the relative phase between probe
and pump light locked to π, and relative phase between local
oscillator and amplitude squeezed light at 0. For the further
usage in magnetic field measurement, the squeezing bandwidth
down to hertz or hundreds-hertz regime is needed. At such
low frequency band, the degradation of squeezing need to be
overcome by the careful control of the intensity noise, beam jitter,parasitic interference etc.

10029-38, Session Post

Realization of 318.6-nm high-power
ultraviolet laser for single-photon Rydberg
excitation of cesium atoms

and corresponding optical-optical conversion efficiency is 38.0%.
The output red laser has good power stability and beam quality.
Then it is converted to UV by cavity-enhanced SHG. Over 2.26
W tunable 318.6 nm laser is generated with 4.0 W of incident
red laser, and the doubling efficiency is 56.5%. The output UV
laser can be continuously tuned over 6 GHz, and the typicalpower fluctuation is less than 0.87% (root-mean-square value)
over 30 minutes. The beam quality factors, M2 X and M2 Y, aremeasured to be 1.16 and 1.48, respectively. Besides, we estimate
the linewidth of the UV laser should be less than 10 kHz. This
318.6 nm UV laser provides a solid foundation for the subsequent
single-step 6S1/2-nP (n = 70 ~ 100) Rydberg excitation of cesium
atoms.

10029-39, Session Post

Two-step quantum secure directcommunication with frequency coding
Xueliang Zhao, Dong Ruan, Tsinghua Univ. (China)
Quantum secure direct communication (QSDC) is an importantcomponent of quantum communication, it can transmit thesecret information directly without establishing a key first.
The first QSDC protocol is two-step protocol. It was designed
based on ideal channel. When it comes to practical application,
noisy should be considered. Recently, the frequency encoded
DL04 QSDC protocol has been proposed and experimentallydemonstrated [Jianyong Hu et al, Experimental quantum secure
direct communication with single photons. Light: Science &Applications, 2016; doi: 10.1038/lsa.2016.144.]. Inspired by thispaper, we propose a two-step protocol with frequency coding,which makes robust against noise and loss. Frequency coding
scheme encodes information on an EPR pair block as periodic
sequences of different frequencies, rather than encoding theinformation directly on individual EPR pairs. When the receiver
get the sequences, he can read out the information by analyzing
its frequency by using the discrete time Fourier transform.
Every EPR pairs have four states, it suggest that four different
amplitude values can be used, so that one sequence can obtain
three different frequencies. Meanwhile, we have numericallysimulated the scheme in a noisy channel, and find it has a strong
ability to resist channel loss and error. In addition, we also give arough estimate of channel noise upper limit.

10029-40, Session Post

Jieying Wang, Jiandong Bai, Jun He, Junmin Wang, Shanxi
Univ. (China)

Efficient simulation of open quantum
system in duality quantum computing

Rydberg atoms are of great significance in quantum information
process and quantum optics area. The strong interaction between
neighboring Rydberg atoms make the Rydberg blockademechanism become a promising candidate to observe atoms
entanglement, Rabi oscillation, and implementation of C-NOT
two-qubit gate. For highly excited Rydberg state, if we choose
a single-step excitation to a desired Rydberg state, the problem
arising from the population of intermediate state can be avoided.
But the photon energy of single-step transition from the groundstate to the Rydberg state is very large, the excitation laser
usually needs to work in ultra-violet (UV) region. To drive thecesium-133 atoms from 6S1/2 state to nP3/2 (n=70~100) Rydberg
state via single-step transition, we prepare a high-power andnarrow-linewidth UV laser system at 318.6 nm by single-passsum-frequency generation (SFG) from two infrared fiber lasers to637.2nm red laser and then by cavity-enhanced second-harmonic
generation (SHG).

ShiJie Wei, Gui Lu Long, Tsinghua Univ. (China)

Based on the commercially available components and efficientnonlinear frequency conversion technology, we demonstrate 8.75
W single-frequency 637.2 nm red light by single-pass SFG of two
infrared lasers at 1560.5 nm and 1076.9 nm in PPMgO:LN crystal,

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We proposed an efficient quantum algorithm for simulating
Hamiltonian in an open quantum system on a duality quantum
computer. In the algorithm, the time evolution of open quantum
system is realized by using Kraus operators which is naturally
realized in duality quantum computing. The query complexityof the algorithm is reduced from d^4 to d^3 , where d is thedimension of the open quantum system. The duality quantum
algorithm provides an exponential improvement in precision than
Lloyd’s algorithm because of use of a truncated Taylor series of
evolution operators.

10029-41, Session Post

Tunable and flat optical delay line basedon double rings resonators
Kaiyue Qi, Yundong Zhang, Yongfeng Wu, Chang Qiu Yu,
Hui Li, Ping Yuan, Harbin Institute of Technology (China)

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Conference 10029: Quantum and Nonlinear Optics IV

We theoretically investigate a fundamental structure which
consists of series-coupled double ring resonators and two
straight waveguides. To be more specific, two rings and threestraight waveguides are included in the structure, and they areconnected by four couplers. The transmission and phase shift
in the structure are calculated through transfer matrix theory.
The simulation results show that the series-coupled double ring
resonators can be used to realize flat optical delay line, and this
delay line is tunable which are achieved by adjusting four tunableself-coupling coefficients and two ring perimeters. Additionally,an EIT-like resonance can be obtained in this structure. And
we could adjust the attenuation factor of ring waveguide andcoupling coefficients to realize a flatter delay line. The groupdelay can vary from 80ns to 1.5us through changing the valuesof four coupling coefficients. The group delay can vary from
2?10-5ns to 1.5us for different ring perimeters. We could alsoachieve a tunable bandwidth through choosing different coupling
coefficients .These results indicate that this structure can be wellapplied in slow slight and will mitigate the deleterious effects
of group delay dispersion. At the same time, we can observe an
EIT-like spectrum that the transmission line shape has a higher
transmission rate and a smaller loss at the resonance point. The
EIT-like phenomenon has a very wide range of applications in
optical pulse reduction, storage and release. The ability to realize
these phenomena is important for applications such as opticalswitch, as well as tunable bandwidth filter.

10029-42, Session Post

Observation of EIT-like spectrum in theeye-like ring resonator
Kai Ma, Yundong Zhang, Yongfeng Wu, Chang Qiu Yu, Hui
Li, Ping Yuan, Harbin Institute of Technology (China)
In this paper, we theoretically analyze the electromagneticallyinduced transparency(EIT)-like spectrum in the Eye-like resonator
configuration. The eye-like structure is composed of two bus
waveguides coupling with the outer ring and the two rings
coupling together which have different perimeters. The whole
structure looks like an eye as it is called. The EIT-like spectrum
results from the interference between the inner ring and theouter ring. We choose the 4 coupling coefficients and theattenuation factors of the ring waveguide for us to control, otherparameters are carefully picked for beautiful EIT-like line shape.
We obtain a tunable group delay and the tunable bandwidthof the transparency window through changing the coupling
coefficients and the attenuation factor of inner and outer ring.
And the group delay can access to 0.3ns for the slow light withthe transmittance up to 98.76%. We can also obtain the groupdelay lower than -50ns for the superluminal light. And thetransmittance window can vary from 24THz to less than 7.4THz
as we control the coupling coefficients. Some other interesting
work have also being done that the tunable group delay can beachieved through choosing different attenuation factors of theinner and the outer ring, but at the same time it may lose line
shape if the parameter is small enough. The tunable group delay
and the bandwidth which are realized by choosing appropriate
parameters will have potential application in optical switching or
tunable delay lines and tunable bandwidth filter.

10029-43, Session Post

Highly-coherent supercontinuum
generation in strip/slot hybrid As2S3
waveguide with low and ultra-flat
dispersion
Shuangxiang Yan, Chao Mei, Jinhui Yuan, Kuiru Wang,
Xinzhu Sang, Binbin Yan, Chongxiu Yu, Beijing Univ. of

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Posts and Telecommunications (China)
Highly coherent supercontinuum (SC) has many applications suchas broadband optical sources and frequency comb generation.
In previous works, low and flat dispersion characteristic plays animportant role in highly coherence SC generation.
In this work, two kinds of strip/slot hybrid As2S3 waveguides
with the silicon dioxide slots, which are demonstrated to have
low and flat dispersion profiles are proposed. And the nonlinear
optical dynamics of SC generation are studied numerically byusing the nonlinear Schrödinger equation. For the waveguidewith a vertical silicon dioxide slot, the dispersion between ±22
ps/(nm?km) from 1432 to 2809 nm and the nonlinear coefficientof 5.842 /W/m at 2000 nm are simultaneously obtained byadjusting the structure parameters. Moreover, when the 120-fs
pulses with central wavelength of 2 ?m and peak power of 100
W are used as the pump, the SC covering from 1392 to 2916
nm at -35 dB level is generated in a 5.5-mm waveguide withhigh coherence of ~1 in the spectrum range considered. For the
waveguide with a horizontal silicon dioxide slot, the dispersion
between ±4 ps/(nm?km) from 1685 to 2770 nm and the nonlinear
coefficient of 10.7 /W/m at 2 ?m can be achieved. Under the samepump condition, the -35 dB bandwidth of SC with coherence of~1, generated in a 5.5-mm waveguide, spans from 1212 to 3979
nm. The simulation results show the horizontal slot structure ismore suitable for generating wider SC with high coherence which
can be applied to generate broadband optical frequency comb.

10029-44, Session Post

Characteristics of 1.9-um laser emission
from hydrogen-filled hollow-core fiber bystimulated Raman scattering
Bo Gu, Yubin Chen, Zefeng Wang, National Univ. of
Defense Technology (China)
Due to the high Raman gain coefficient and large Raman
frequency shift, stimulated Raman scattering (SRS) of gases
has been recognized as an effective means to obtain tunable,
narrow linewidth sources of otherwise unobtainable wavelengths,
especially in the ultra violet and infrared range. Historically, due
to the very short effective interaction length, SRS in gases has
required high pump powers. And the conversion efficiency tothe desired wavelength is usually very low, due to additional
generation of other unwanted lines. Hollow core fibers havemade it possible to obtain high conversion efficiency for SRS ingases, as it can provide a very long effective interaction length,
high pump intensity, and the possibility of control of the effective
gain spectrum. In our previous works, we have demonstrated
the first effective 1.9 ?m Raman converter with hydrogen-filled
negative curvature hollow-core fiber pumped with a 1064 nm
pulse microchip laser. Here, we give the detailed pulses, linewidth,polarization and modes characteristics of the 1.9 Raman source
for the first time. We found that the pulse duration of the 1.9?m Raman is compressed observably compared to the pumppulse duration; the linewidth is about 1GHz, which is the samelevel of the pump laser; the output light spot is a nearly perfectfundamental mode although the pump is multi-mode in thehollow core fiber; the Raman conversion efficient is closely
related to the polarization properties of the pump laser and thehollow core fiber.

10029-45, Session Post

Nonlinear generation of higher-ordermodes by intermodal four-wave mixing in
multimode fibers
Tong Liu, Sheng-Ping Chen, Jing Hou, National Univ. of#PhotonicsAsia

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Conference 10029: Quantum and Nonlinear Optics IV

Defense Technology (China)
Higher-order modes of optical fibers have recently attracted
renewed interest in applications covering high-speed opticalcommunication, nonlinear extension of laser spectrum, novel
design of high-power fiber lasers, to name just a few. Their exotic
intensity patterns and phase/polarization structures are favorable
in many situations, which make them be useful alternatives
or supplements to the commonly employed fundamental
mode. There are many approaches to generate such modes
in a multimode fiber; however, most of them are subject tospecific qualifications and limited in efficiency and applicability.
To controllably excite specific higher-order modes with highpurity is still not a trivial task. Here we present our experimental
results and analysis on the generation of higher-order modes
by intermodal four-wave mixing, which is a nonlinear effect that
requires phase-matching between interacting waves. Whenintense light is injected into a multimode fiber and excite a
mixture of various modes, the phase-matching condition ofintermodal four-wave mixing acts as a mode filter and specificmode combinations are generated at well-predicted Stokes andanti-Stokes wavelengths. Although this phenomenon was founddecades ago, only few attempts have been made to exploit it asa useful tool. Moreover, despite a significant amount of reports
mentioning the observation of such effects, there is still a lackof detailed investigations. In this manuscript, we systemicallystudy the intermodal four-wave mixing in multimode fibers withdifferent geometric parameters and find that it is feasible togenerate high-quality higher-order modes in a controlled manner.

10029-46, Session Post

Study of the nonlinear optical absorption
and refraction of indium-doped zinc-oxidethin-films (IZO) using Z-scan technique
Maung Htwe Zin, Yundong Zhang, Harbin Institute ofTechnology (China); Chengbao Yao, Harbin Normal Univ.
(China); Hui Li, Ping Yuan, Harbin Institute of Technology(China)We report the nonlinear optical properties of indium doped
zinc oxide thin film (IZO). IZO thin films were grown on
sapphire substrate by radio frequency (RF/DC) magnetron
sputtering technique. During the IZO thin film sputtering
process, ZnO and In disc were install on RF and DC target
respectively. The sputtering power of In (DC target power)
was kept at (2 and 5 W) while ZnO target power was 100 W.
The structural characterization, surface morphology and linear
optical properties of IZO thin films were carried out using
X-ray diffraction (XRD), scanning electron microscopy (SEM)and UV-VIS spectrometer. The XRD result shows that IZO thinfilms exhibit the polycrystalline characteristics and still retained
hexagonal wurtzite structure of ZnO. The crystallite size of
IZO are increased with In content. This result reveals that the
crystallinity of IZO thin films are improved with DC powerincreasing. The SEM images of IZO agreed with XRD results
because of the grain size of IZO are increased. For linear opticalstudies, IZO thin films show high transmittances at visible region(above 50 %) and the band gap values are increased due toindium is the donor type semiconductor materials which provides
more electrons and lead to increased the optical band gap. In
addition, the nonlinear optical absorption and refraction of IZO
thin films were investigated using nanosecond Z-scan technique.
The Q-switch Nd-YAG laser with 532 nm wavelength is usedas the excitation laser source. The pulse duration and energy
are 6 ns and 9 uJ respectively. The incident laser wavelength
was collected using lens with 300 mm focal length. In orderto study the nonlinear optical absorption, we carried out the
open aperture (OA) Z-scan method. The IZO thin films exhibit
valley shape normalized transmittance. This result reveals that
OA results show reverse saturable (RSA) and studied the two-

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photon nonlinear optical absorption of IZO thin films. Moreover,
we carried out the closed aperture (CA) Z-scan to study thenonlinear refraction. The CA normalized transmittance curves are
exhibit self focusing (valley-peak) characteristics which reveal the
IZO thin films have positive nonlinear refractive behaviors. Thesestudies make the IZO thin films as the applications in nonlinear
optical devices.

10029-47, Session Post

Silicon photonic chips for improved-gluedbinary-tree problem
Fan Qi, Qingyan Ma, Yufei Wang, Wanhua zheng, Instituteof Semiconductors (China)
Quantum walks can be used to accelerate search in graphs, which
is useful in computer science and promising for future universal
quantum computers. A typical example of quantum acceleration
is about the improved-glued-binary-tree problem. For a treeof depth n, the arrival time of a classical random walk is O(2n)and the arrival time of a quantum walk is O(n). As we can see,quantum algorithm brings about an exponential speedup. The
quantum algorithm is based on a one-dimension continuous timequantum walks, which can be implemented by an integrated
waveguide array. Here we construct the array on a silicon-oninsulator, which has a 220 nm-thick waveguide layer and 3?m-thick buried oxide layer. The waveguides are constructed byetching 70 nm into the waveguide layer and the width of the rib
is 420 nm. For a tree of depth 4, there should be 10 waveguides
in the array. The coupling constant between waveguide 5 andwaveguide 6 is 0.0274 ?m-1; the coupling constants elsewhereare 0.0194 ?m-1. When the wavelength of the injecting photon is1550 nm, the gap between waveguide 5 and waveguide 6 is 0.99
?m and the gap elsewhere is 1.1 ?m. After propagation a distanceof 304?m in the array, we can find a maximum arrival probability
0.723. Since only single-photon quantum walks are involved in
the algorithm, we can completely simulate this with classicalcoherent light. The above design is verified with classical lightpropagation simulation.

10029-48, Session Post

Tunable Q-switched random fiber laser
Jiangming Xu, Jun Ye, Hu Xiao, Jinyong Leng, Hanwei
Zhang, Pu Zhou, National Univ. of Defense Technology(China)Random fiber lasers (RFL) are of great importance in many
fields, such as illumination sources, sensing technology andspectroscopic monitoring for their typical features of modeless,cavity-less and low coherence length. In most of previous
investigations, RFLs normally work in continuous-wave withspecial wavelength. A tunable Q-switched RFL takes advantagesof the high peak power and relatively wide gain bandwidth. In
this manuscript, we propose and experimentally investigate
a tunable Q-switched RFL. The pump source is a tunable(1035~1090 nm) fiber laser with maximal output power of about
6.5 W. Half-opened cavity of the tunable Q-switched RFL iscomposed by a piece of 3 km single mode fiber (SMF) and 50:50
wideband coupler (~100 nm), which function as distributed
feedback mirrors and fiber loop mirror (FLM), respectively. The
FLM is switched on/off by means of the AOM thus changing
the Q-factor of the distributed cavity. As a result, 1087~1144 nm
tunable pulsed random lasing can be obtained by adjusting theoperation wavelength of pump laser. The repetition frequency
is 500 kHz, which is determined by the operation parametersof AOM. And the pulse width is about 30~75 ns, which is far
narrower than the pulse width of the driving electrical signal forthe pump depletion and is changing in the power scaling process.

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Conference 10029: Quantum and Nonlinear Optics IV

To the best of our knowledge, this is the first reported tunable
Q-switched RFL, and further power scaling and tuning range
exploration is available in the case of more powerful pump source
and optimization of system parameters.

10029-49, Session Post

Duration-controllable square-wave pulse
from an L band dissipative soliton fiber
laser based on the dispersive Fouriertransformation technique
Dan Yan, Hebei Normal Univ. (China)
We experimentally demonstrate the duration-controllable
square-wave pulse from an L band dissipative soliton (DS) fiber
laser based on the dispersive Fourier transformation (DFT)technique. The rectangular spectrum emitted from an L banddissipative soliton fiber laser is mapped into a time-domain
coherent rectangular waveform through the DFT technique. The
duration of the square-wave pulse can be controllable with theadjustments of the pump power. The results demonstrate that it
is an effective and flexible way to achieve duration-controllable
square-wave pulses by combinating with DFT technique and DS
fiber laser.

10029-50, Session Post

Simulation and measurement of thresholdpump power for the stimulated Brillouinscattering (SBS) and stimulated Raman
scattering (SRS) in ytterbium-doped
double-clad CW fiber amplifiers
Mohammad Abdollahi, Malek Bagheri Haroni, Univ. of
Isfahan (Iran, Islamic Republic of); Meisam Fakhari,
Univ. of Kashan (Iran, Islamic Republic of); Mohammad
J. Hekmat, Mohammad Kanani, Hosein Normohamadi,
Narges Shahriari, Isfahan Univ. of Technology (Iran, Islamic
Republic of)Ytterbium-doped fiber amplifiers and lasers have attracted muchattention in recent years because of their unique properties suchas broad gain. In many applications such as remote sensing andnonlinear frequency generation high-power narrow-linewidth CW
sources are required to posses high conversion efficiency. Master
Oscillator Power Amplifiers (MOPAs) are suitable configurations
for these purposes in terms of appropriate control over signal
wavelength and bandwidth. Getting high level of powers
encounters serious problems that originate from nonlinear effects
such as SBS (mostly because of narrow-linewidth) and SRS
that are detrimental phenomena. So it’s of prime importance tosuppress these effects in order to get high level of powers. In ourwork we’ve considered a general description about amplifying
process of narrow-linewidth CW signals in different regimes(small-signal and large-signal) by including all affecting terms
in coupled differential equations which sheds light on importantconcepts. ASE terms together with nonlinear ones can give agreat description about this process. Also in experimental setups
we’ve used Yb-1200-LMA-20/400 active fiber made by nlightcompany that’s very common in high power CW Ytterbiumdoped fiber amplifiers and examined it’s threshold pump powers
under both forward and backward pumping configuration that’s,
to the best of our knowledge, the first report on using backward
pumping configuration to suppress nonlinear effects. We also
discuss some practical issues in experimental setups regarding
measuring the threshold of nonlinear effects. Our work can beconsidered as an interactive work in which experimental results
shed light on theoretical ones.

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10029-51, Session Post

Highly-coherent octave-spanningsupercontinuum generation in CS2-filled
photonic crystal fiber with strong slow
nonlinearity
Liyun Wang, Beijing Univ. of Posts andTelecommunications (China); Jinhui Yuan, Hong Kong
Polytechnic Univ. (China); Chongxiu Yu, Kuiru Wang,
Xinzhu Sang, Binbin Yan, Beijing Univ. of Posts andTelecommunications (China)
In this paper, the supercontinuum (SC) generation in a carbon
disulfide (CS2)-filled photonic crystal fiber (PCF) with strong
slow nonlinearity was investigated. CS2 is a material that has
high nonlinearity coefficient and well transparency in infrared.
What’s more, the slow nonlinearity is very strong in this material.
When the PCF was pumped at 1.55 ?m in the anomalous
dispersion region, the generated SC was within the range from
0.99 to 2.32 ?m, at -40 dB level with high coherence in theanomalous dispersion region. Moreover, the influences of the slow
nonlinearity, the temperature, the pump pulse width, the peak
power,and the fiber length on the supercontinuum generation(SCG) was studied. To our best knowledge, this is the first
demonstration on generating the octave-spanning SC with highcoherence in the CS2-filled PCF and the first time to simulate therole of the slow nonlinearity in enhancing the coherence of thegenerated spectrum specifically.

10029-52, Session Post

Two-photon absorption-induced opticalpower limiting behavior of strong
femtosecond hyper-Gaussian pulses
Ji-Cai Liu, Xing-Zhe Li, Ying Zhang, North China ElectricPower Univ. (China)
The propagation of strong femtosecond hyper-Gaussian pulses
in an organic molecular medium is studied by solving numericallythe Maxwell–Bloch equations using an iterative predictorcorrector finite-difference time-domain technique. The temporalshape of the hyper-Gaussian laser field is written as F(t)=F_0
exp(-ln2/2 (t-t_0 )^(2^n )/(?/2)^(2^n )), where ? is the full-widthat half-maximum of the temporal profile F^2 (t), F_0 is the peakvalue of the field amplitude, and n=1,2,3? is the order of thehyper-Gaussian pulse. The carrier-wave frequency of the field
is tuned in two-photon resonance with the molecular system
simplified by a cascade three-level model. Strong optical power
limiting behavior is observed for the hyper-Gaussian pulses ofdifferent orders. Usually for long pulses, the dynamics of twophoton absorption is determined by the “two-photon area” of thepulse, which is proportional to the time integral of F^2 (t). For theultrashort hyper-Gaussian pulses, it is found that the “two-photonarea” is no further the deciding quantity of the two-photon
induced dynamics. With the same value of the “two-photon area”,
pulses with different temporal profiles and different values ofthe pulse duration and field strength will induce different twophoton absorption and optical limiting processes. With the same
pulse duration ? and field amplitude F_0, pulses of a lower order(smaller n) is found to have a larger input “two-photon area” buta smaller output area, and therefore show a better optical limiting
behavior. Pulses of a low order has a narrow bandwidth, andtherefore the intermediate state of the molecule is less involvedin the two-photon absorption process.

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10029-54, Session Post

10029-56, Session Post

Influence of Doppler effect on thephenomenon of electromagneticallyinduced transparency

Feedback spectroscopy of dynamicallyexcited coherent population trapping
resonance in Rb vapour

Qiyong Tao, Guiyin Zhang, Haiming Zheng, North China
Electric Power Univ. (China)

Sergey M. Kobtsev, Daba A. Radnatarov, Sergey A.
Khripunov, Novosibirsk State Univ. (Russian Federation);
Alexey V. Taichenachev, Valeriy I. Yudin, Novosibirsk
State Univ. (Russian Federation) and Institute of Laser
Physics SB RAS (Russian Federation); Maxim Y. Basalaev,
Novosibirsk State Technical Univ. (Russian Federation);
Tatiana Steschenko, Ivan Popkov, Valerii Andryushkov,
Novosibirsk State Univ. (Russian Federation)

Electromagnetically induced transparency (EIT) which enables
propagation of light through an opaque medium without
significant attenuation is one of the many unusual and interesting
phenomena produced by atomic coherence and interference
effects. Up to now, a large amount of research has been carriedout where the atoms were taken as static. In fact, atoms often
show random thermal motion. There exists very strong Doppler
effect, especially in the situation of high temperature.
In this article, we presented a theoretical study about the
influence of Doppler effect on EIT phenomenon with thetheory of density matrix equation. A cascade type three-levelsystem and the function of Maxwell velocity distribution isadopted during the course. The results indicate that without
considering Doppler effect, EIT windows depends on Rabi
frequency of the coupling and probing field, while regardless oftemperature. When took the Doppler effect into consideration,
an apparent transparent window can be observed only when thetemperature is less than 50K due to Doppler broadening of theabsorption curve. With the increase of temperature, transparent
phenomenon quickly disappeared and the double peaks of
Aulter-Townes will instead of the EIT transparent window as
the temperature get to the room one. This is why most of theexperimental investigation about EIT was taken in cold atomic
systems. At room temperature, we can only detect Aulter-Townes
double peaks with a strong coupling field but not the EIT window.

10029-55, Session Post

Fibre amplifying loop mirror withnonlinearity independent of the intensityof intra-cavity radiation
Sergey M. Kobtsev, Sergey V. Smirnov, Alexey V. Ivanenko,
Novosibirsk State Univ. (Russian Federation)
Among the demerits of standard nonlinear amplifying loop
mirrors (NALM), one can single out the dependence of its
reflectivity upon the intensity of the intra-cavity. This results
in a relatively narrow range of radiation power, within whichstable mode-locked operation of a fibre laser with NALM can beachieved. NALM’s function due to an asymmetric distribution of
amplification (loss) along the fibre and/or due to an asymmetriccoupler with coupling ration differing from 50/50. Althoughcounter-propagating waves cover an exactly identical distancewithin the non-linear loop, their non-linear phase incursion
is different because of an asymmetric position of the active
fibre. Consequently, the counter-propagating waves exiting thenonlinear loop interfere differently at different levels of radiation
power, thus leading to dependence of NALM reflectivity upon theradiation power. However, as the power level is raised, stable laser
operation requires that condition “nonlinear phase incursion < pi”
hold true. Otherwise, the dependence of NALM reflectivity uponradiation power becomes non-monotonic, leading to disruptionof generation and/or to formation of pulse trains stochasticallyfilled with sub-pulses. This work reports for the first time thatin the process of generation, the NALM reflectivity may becontrolled independently of the intra-cavity radiation powerby using two different active media with independent pumpsources. The newly proposed layout allows stable mode locking
within a substantially broader radiation power range and enables
achievement of record-high pulse parameters.

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SPIE Photonics Asia·

For the first time, this work presents exploration of CPT
resonance properties in the lambda-configuration of D1 linein 87Rb atoms with dynamic excitation using a feedback
spectroscopy method. Introduction of feedback loop in quasistationary mode when the frequency of CPT resonance scanning
does not exceed 1 Hz results in a dramatic improvement of theresonance magnitude, tens of times that without feedback [1],even though this requires relatively deep modulation of thepump intensity. The present work demonstrates, for the firsttime, that application of the proposed feedback spectroscopy
method to a system with dynamic CPT resonance excitation
when the CPT resonance scan frequency exceeds 100 Hz also
leads to a crucial enhancement (tens of times) of the resonancemagnitude, which is similar to the enhancement obtained in thequasi-stationary mode. It is quite remarkable that the resonancestrength enhancement in the dynamic excitation mode can bereached at an order of magnitude shallower depth of pumpradiation modulation. Our work presents the results obtained instudy of the dependence of CPT resonance parameters upon
the frequency at which it is scanned over the range of 1 Hz to
3 kHz, both with and without the feed-back loop. The effect offeed-back loop parameters on the shape of dynamically induced
CPT resonances has been identified. Further discussed are thepossibilities of using the proposed feed-back spectroscopy
method in order to improve metrological performance ofcompact atomic clocks based upon CPT resonance references.
1. V. Yudin, et al. Feedback spectroscopy of atomic resonances.
Phys. Rev. A, 87,6,063806 (2013)

10029-57, Session Post

Performance analysis of passive optical
network systems based on the IM/DD
OFDM modulation format
Sofien Mhatli, Besma Wchir, Abderrazek Ben Abdallah,
Ecole Polytechnique de Tunisie (Tunisia); Mutsam
Jarajreh, Tabuk Univ. (Saudi Arabia); Rabah Attia, Ecole
Polytechnique de Tunisie (Tunisia)
Motivated by the robust immunity to interference caused bydispersive channels as well as the higher spectrum efficiency,
Orthogonal Frequency Division Multiplexing has been widely
considered as one of the strongest contenders for high-speed
NG-PONs, which satisfies the huge surge in demand of highspeed broadband services. However, due to the nonlinear natureof the transmitting medium, optical OFDM systems will sufferfrom signal degradation which limits the system capacity and the
maximum transmission distance. This paper investigates these
impairments in the context of IM/DD systems. In this respect,a theoretical description of the nonlinear Kerr effect based on
the first order perturbation effect is presented in accordance toprevious works.

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Conference 10029: Quantum and Nonlinear Optics IV

10029-58, Session Post

Analytical model of an IMDD optical
OFDM modem
Sofien Mhatli, Besma Wchir, Abderrazek Ben Abdallah,
Mutsam Jarajreh, Rabah Attia, Ecole Polytechnique deTunisie (Tunisia)
In this paper, we present an analytical formula of an optical
OFDM modem. Bit-Error-Ratio (BER) of intensity modulated
optical orthogonal frequency division multiplexing (OFDM)
system is analytically evaluated accounting for nonlinear digital
baseband distortion in the transmitter and additive noise in
the photo receiver. The system BER is evaluated for the OFDM
system with multi-level quadrature amplitude modulation (QAM)
applied to the optical signal subcarriers. Results obtained bychanging the fiber length, laser parameters and using single
mode fiber with negative and positive dispersion are calculated
in order to demonstrate the validity and versatility of the theory
provided in this paper. Therefore, a novel analytical formulation ispresented as a versatile tool for the description and study of IM/
DD OOFDM systems with variable design parameters.The resultspresented in this paper are validated by numerical simulations.

10029-19, Session 5

Novel optical properties of graphene
oxide films (Invited Paper)
Baohua Jia, Swinburne Univ. of Technology (Australia)
Graphene and its derivatives have attracted unprecedented
enthusiasm during the past decade due to their exceptional
mechanical, thermal, optical, and electrical properties. In
particular, graphene oxide (GO), seen as the graphene sheet
covalently decorated with various oxygen functional groups
either on the basal plane or at the edge, becomes an attractive
material itself due to a unique set of physical and chemical
characteristics arising from the hybridization of sp2 and sp3
carbon atoms.
This article investigates the optics and applications of GO andreduced graphene oxide (rGO) films by using the one-stepmask-free direct laser printing (DLP) method [1-3]. Firstly,
the synthesis and laser reduction of GO films are discussed indetails. Then the fundamental optical properties of both GO
and rGO films have been investigated, including their linear andnonlinear optical properties. Finally based on the characterization
and understanding of their optical activities, various optical
functional components have been designed and realized bothexperimentally and theoretically. Our results have demonstrated
the great potentials of GO films as an emerging integratable
platform for ultrathin, light-weight and flexible photonic devices.
[1] X. Zheng, B. Jia, X. Chen, M. Gu, Adv. Mater 26, 2699 (2014).
[2] S. Fraser, X. Zheng, L. Qiu, D. Li, B. Jia, Applied Physics
Letters, 107, 031112 (2015).
[3] X. Zheng, B. Jia, H. Lin, L. Qiu, D. Li, M. Gu, Nature
Communications, 6, 8433 (2015).

10029-20, Session 5

Biomedical imaging with stimulated
Raman scattering (SRS) microscopy(Invited Paper)
Minbiao Ji, Fudan Univ. (China)
Stimulated Raman scattering (SRS) microscopy is a coherent
version of Raman microscopy. SRS has unique capabilities of

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Follow us on:label-free imaging with high chemical specificity and sensitivity. It
could selectively image the distributions of biomolecules (such as
lipids, protein and DNA) based on their characteristic vibrational
spectra. We’ve applied SRS microscopy to a few biomedical
applications, including brain tumor imaging, DNA imaging anddrug deliveries.

10029-21, Session 5

Parametric wavelength conversion inphotonic crystal fibers (Invited Paper)
Sigang Yang, Zhaohui Wu, Yi Yang, Minghua Chen,
Shizhong Xie, Tsinghua Univ. (China)
Nonlinear wavelength conversion provides flexible solutions
for generating wideband tunable radiation in novel wavelength
band. Parametric process in photonic crystal fibers (PCFs) has
attracted comprehensive interests since it can act as broadband
tunable light sources in non-conventional wavelength bands. The
current state-of-the-art photonic crystal fibers can provide more
freedom for customizing the dispersion and nonlinearity whichis critical to the nonlinear process, such as four wave mixing(FWM), compared with the traditional fibers fabricated withdoping techniques. Here we demonstrate broadband parametricwavelength conversion in our homemade photonic crystal fibers.
The zero dispersion wavelength (ZDW) of PCFs is critical forthe requirement of phase matching condition in the parametricfour wave mixing process. Firstly a procedure of the theoreticaldesign of PCF with the ZDW at 1060 nm is proposed throughour homemade simulation software. A group of PCF samples
with gradually variable parameters are fabricated according to
the theoretical design. The broadband parametric gain around1060 nm band is demonstrated pumped with our homemademode locked fiber laser in the anomalous dispersion region.
Also a narrow gain band with very large wavelength detunewith the pump wavelength in the normal dispersion region isrealized. Wavelength conversion with a span of 194 nm is realized.
Furthermore a fiber optical parametric oscillator based on the
fabricated PCF is built up. A wavelength tunable range as highas 340 nm is obtained. This report demonstrates a systematic
procedure to realize wide band wavelength conversion based on
PCFs.

10029-22, Session 5

Giant optical nonlinearity of a single
plasmonic nanostructure (Invited Paper)
Pavel N. Melentiev, Institute of Spectroscopy (RussianFederation)
Nonlinear optical interaction of laser light with metal
nanoparticles is limited by high metal losses that leads todramatic temperature rise and to catastrophic meltdown ofnanoparticle, making plasmonic nanoparticles a poor match
for applications requiring high efficiency, such as harmonics
generation and wavelength conversion [1]. There is another typeof structures - nanoholes made in thin metal films. Our research[2] shows that nanoopenings created in a metal film are capableof withstanding a considerably higher intensity of the radiation
incident on it than isolated nanoparticles, and, correspondingly,
as a nonlinear element, can be more efficient.
We present results of experimental research of a strong
nonlinearity of a single plasmonic nanostructure in a geometryof Split – Hole Resonator (SHR): (1) generation of harmonics in
UV and visible spectral ranges [3], (2) multi-photon induced
luminescence; (3) the practical application of the giant opticalnonlinearity of plasmonic nanoholes to implement (i) all-opticaldisplay, (ii) nanolocalized and femtosecond laser sources, (iii)
optical nanoscale multi-order auto correlator.

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Conference 10029: Quantum and Nonlinear Optics IV

flux of a hybrid polarized beam could be manipulated by tuning
the magnitude of the isotropic optical nonlinearity, which may
find interesting applications in nonlinear mechanism analysis,
nonlinear characterization technique, and SAM manipulation.

REFERENCES
1. Khurgin, J. B. and Sun, G., “Third-order nonlinear plasmonic
materials: Enhancement and limitations”, Phys. Rev. A, Vol. 88,
053838, 2013.
2. Melentiev, P. N. et al., “Giant optical nonlinearity of a single
plasmonic nanostructure”, Opt. Express, Vol. 21, 13896, 2013.

10029-25, Session 5

3. Melentiev, P. N. et al., “Split Hole Resonator: A nanoscale UV
light source” Nano Letters 16(2), 1138-1142 (2016).

Design and demonstration of a novel
broadband frequency conversion system

10029-23, Session 5

Meizhi Sun, Xiaoqi Zhang, Xiao Liang, Jun Kang, Ailin Guo,
Qingwei Yang, Zijian Cui, Yanli Zhang, Junyong Zhang,
Xinglong Xie, Jianqiang Zhu, Zunqi Lin, Shanghai Instituteof Optics and Fine Mechanics (China)

Fiber-based polarization-entangled
photon pair sources for quantum coding
Feng Zhu, Wei Zhang, Yidong Huang, Tsinghua Univ.
(China)In this paper, a generation scheme of telecom band frequencydegenerate polarization entangled state is proposed anddemonstrated experimentally. It is based on the vector
spontaneous four wave mixing (SFWM) process in a Sagnac
dispersion shifted fiber loop, in which two frequency-degenerate
and polarization orthogonal biphoton states generate along theclockwise and counter-clockwise directions, respectively. The
quantum interference between them at the 50:50 fiber coupler ofthe fiber loop separates the two frequency-degenerate photons
in a pair, leading to the generation of polarization entanglement.
The pump light is from a 40 MHz mode-locking fiber laser. It
is amplified by an Erbium Doped Fiber Amplifier (EDFA). A
cascade Dense Wavelength Division Multiplexing (DWDM) is
used to narrow the width of the pump light. Two other cascade
Dense Wavelength Division Multiplexing (DWDM) are used
to filter the noise photons from signal and idler photons. The
photons are detected by the NbN superconducting nanowire
single photon detectors (SNSPDs). The events are recorded bya time correlated single photon counting module (TCSPC). The
raw fringe visibilities of the two-photon interferences under two
non-orthogonal polarization bases are higher than 89%. The
coincidence and accidence ratio (CAR) can be higher than 50.
Quantum coding using the polarization entangled Bell states canbe realized by the generated pairs, which is demonstrated by asimplified Bell state measurement with a fringe visibility of 76%.

10029-24, Session 5

Nonlinear polarization evolution of
hybrid polarized beams by isotropic Kerr
nonlinearity

A novel conversion system for broadband chirped pulses ispresented in this report. Three gratings are successively includedin the system, in which the front two of them are of equal line
density and the third grating is twice of the line density. The
nonlinear crystal, like BBO, is placed between the front two
gratings as the second harmonic generator (SHG).The SHG
phase matching for broad spectrum can be realized based on
the fundamental frequency (FH) angular dispersion, provided by
the first grating with certain grating constant and perpendicularincident beam. Diffraction at the second grating separates theFH and SH, which backtracks cross the crystal and is successively
reflected by a dichroic mirror or polarizer into the third grating.
The angular dispersion and spatial chirp can be compensated at
the same time by accurate adjustment of the third grating. As aspatial chirped free dispersive unit, the grating assemble is usefulto regular the SH chirped ratio by changing distance between
the second and third gratings. Theoretical analysis indicates thatthe system can realize effective frequency conversion for FH
bandwidth larger than 20nm, and experimental demonstration is
expected to be carried out soon.

10029-26, Session 5

A novel method for fabrication of fiber
pump combiners
Mohammad J. Hekmat, Hosein Normohamadi, Mohammad
Kanani, A. Mazangi, Isfahan Univ. of Technology (Iran,
Islamic Republic of); Mohammad Abdollahi, Univ. of
Isfahan (Iran, Islamic Republic of)
At this research, a 3x1 pump fiber combiner is fabricated without
using tapering system and expensive cleaver. This component ismade as the follow stages:

Bing Gu, Bo Wen, Guanghao Rui, Yiping Cui, Southeast
Univ. (China)

1. Three 200/220 is cleave and putting to a appropriate capillary
and heated to enough temperature until they are attached
together.

Theoretically, we propose an investigation of the structured lightfield interacting with the isotropic Kerr medium. We obtain theanalytical expression of the focal field of the hybrid polarized
beam based on the vectorial Rayleigh-Sommerfeld formulas
under the paraxial condition. We determine the third-ordernonlinear refractive indexes of an isotropic medium excited by
the vector field with arbitrary ellipticity. Then we numericallysimulate the far-field vectorial self-diffraction behavior andnonlinear ellipse rotation of a hybrid polarized beam by isotropic
Kerr nonlinearity. We systematically study the dependence ofthe self-diffraction behaviors on both the physical origin of the
optical nonlinearity and the nonlinear phase shift. Experimentally,
we observe the vectorial self-diffraction and nonlinear ellipse
rotation behaviors of the femtosecond-pulsed hybrid polarized
beam in carbon disulfide at 800 nm, which is in good agreementwith the theoretical predictions. Our results demonstrate thatthe self-diffraction intensity pattern, the distribution of stateof polarization (SoP), and the spin angular momentum (SAM)

2. After that the fiber bundle endface is heated up to make micro
sphere at the end of that.

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3. On the other hand, a double clad 20/400 fiber is prepared and
we repeat the stage 2 again.
4. At final stage, to micro sphere is spliced together.
Please note that, the critical point is the specification of micro
spheres which are specify the amount of pump fiber combiner
losses.
Our 3x1 pump combiner is studied with maximum power
handling, 220W/port experimentally for several hours without
any problem.

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Conference 10029: Quantum and Nonlinear Optics IV

10029-27, Session 610029-29, Session 6

Experimental realization of opticallyinduced transparency in a micro-cavity(Invited Paper)

pre-chirp managed nonlinear amplificationfor >100-W ultrafast sources (Invited
Paper)

Yuanlin Zheng, Jianfan Yang, Zhenhua Shen, Jianjun Cao,
Xianfeng Chen, Shanghai Jiao Tong Univ. (China); Xiaogan
Liang, Univ. of Michigan (United States); Wenjie Wan,
Shanghai Jiao Tong Univ. (China)

Wei Liu, Yizhou Liu, Damian N. Schimpf, Deutsches
Elektronen-Synchrotron (Germany); Tino Eidam, Jens
Limpert, Andres Tuennermann, Friedrich-Schiller-Univ.
Jena (Germany); Franz X. Kärtner, Guoqing Chang,
Deutsches Elektronen-Synchrotron (Germany)

Electromagnetically induced transparency (EIT) has its uniqueability of optically controlling transparency windows with low
light in atomic systems. However its practical applications inquantum physics and information science are limited due torigid experimental requirements. With whispering-gallery mode
(WGM) micro-resonators, the analogue of EIT-like effect on achip scale has been realized. And various schemes have been
proposed and demonstrated. The advantage is about their allsolid configuration, miniaturization and controllability, which
offers a unique platform for a compact, integrated solution to
all-optical manipulation of light.
We experimentally demonstrated a new mechanism of opticallyinduced transparency (OIT) in ambient environment. The
new scheme relies on the introduction of a parametric gainby four-wave mixing (FWM) in the micro-cavity in order tocouple nonlinearly two separated resonances of the WGMs. A
signature Fano-like resonance is observed owing to the nonlinear
interference of two coupled resonances. Moreover, we showthat the unidirectional gain of four-wave mixing can lead to a
striking effect of non-reciprocal transmission at the transparency
windows, since the FWM gain is a unidirectional one owing to theconservation law of momentum.
Our unique OIT scheme offers a new platform to study
analogical atomic quantum interference effects in a simpler
manner; moreover, it can be further exploited for critical onchip photonics applications such as optical isolator, all-opticalswitching, and wavelength conversion. Since OIT only relies on
the nonlinearity and resonance properties of the medium, hence
similar features should be ubiquitously expected among anyother physical systems with these characteristics.

10029-28, Session 6

Experimental realization of stimulated
Raman shortcut-to-adiabatic passage withcold atoms (Invited Paper)
Shi-Liang Zhu, Nanjing Univ. (China)
Accurate control of a quantum system is a fundamental
requirement in many areas of modern science ranging fromquantum information processing to high-precision measurements.
A significantly important goal in quantum control is to preparea desired state as fast as possible with sufficient high-fidelity
allowed by available resources and experimental constraints.
Stimulated Raman adiabatic passage (STIRAP) is a robust way torealize high-fidelity state transfer while satisfying the requirementof a sufficiently long operation time for the adiabatic evolution.
In this talk, I will present our recent work on speeding up the
STIRAP. We theoretically propose and then experimentallydemonstrate a shortcut-to-adiabatic protocol to speed up the
STIRAP. By modifying the shapes of the Raman pulses, we
experimentally realize a fast and high-fidelity stimulated Raman
shortcut-to-adiabatic passage (STIRSAP) that is robust against
control parameter variations. The all-optical, robust, and fast
protocol demonstrated here provides an efficient and practical
way to control quantum systems.

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High power, high repetition-rate ultrafast fiber-laser sources are
an enabling technology for scientific applications, such as highphoton flux extreme ultraviolet light sources. To avoid detrimental
nonlinear effects inside fiber amplifiers, these fiber-laser sources
normally employ the well-known chirped-pulse amplification(CPA) technique. Limited by gain narrowing and residual
dispersion mismatch, the compressed pulse duration is typicallylimited to values around 200 fs. A further reduction in pulse
duration necessitates an external nonlinear pulse-compression
stage, which increases the system complexity and reduces thethroughput efficiency.
Recently we proposed and demonstrated pre-chirp managed
amplification (PCMA), in which the seeding pulse was nonlinearly
amplified such that the amplified spectrum was substantiallybroadened. By properly pre-chirping the seeding pulse, theamplified pulse can be compressed with a duration much shorter
than the transform-limited duration allowed by the seeding
spectrum. Using an Yb-doped rod-type large-pitch fiber (LPF) as
the power amplifier, PCMA has enabled us to generate 75 MHz,~60 fs, linearly-polarized pulses with >100-W average power.
We further investigate the energy scalability of PCMA using
circularly polarized seeding pulses. Because the nonlinear
refraction coefficient for the circularly polarized light is 2/3 ofthat for linearly polarized light, using circularly polarized seedcan scale up the pulse energy (and average power) by 1.5 times
without changing the spectral bandwidth of the amplified pulse.

10029-30, Session 6

Controlled cavity quantum optomechanics
with Bose-Einstein condensate
Kashif Ammar Yasir, Wu-Ming Liu, Institute of Physics(China)Cavity-optomechanics, a tool to manipulate mechanical effects
of light to couple optical field with other physical objects,
is the subject of increasing investigations. We investigate
controlled dynamics of such hybrid optomechanical systemcomposed of cigar-shaped Bose-Einstein condensate (BEC)trapped inside high-finesse optical cavity with one movingend mirror and driven by a single mode optical field. We use
another transverse field, which directly interacts with BEC
and scattering photons inside the system, to control bistablebehavior as well as electromagnetically induced transparency(EIT) by manipulating out-going optical field. By increasingtransverse field, we can suppress bistability which may act as
optical switch. It is detected that the strength of transverse
field is not only efficiently amplifying or attenuating out-going
optical mode but also providing an opportunity to enhance thestrength of Fano-interactions which leads to the amplificationof EIT-window. We further investigate SO interaction tuning
optomechanical dynamics of hybrid cavity with SO-coupled BEC.
The collective density excitations of hyperfine states -- serving
as topological oscillators equally coupled to the cavity field-- trigger strongly driven atomic back-action. The strength of
SO-coupling tunes atomic back-action which not only revamps
topological properties and low-temperature dynamics of its own#PhotonicsAsia

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Conference 10029: Quantum and Nonlinear Optics IV

but also controls the effective-temperature of mechanical mirror
and squeezes nonlinear quantum noises, like thermo-mechanicaland photon shot noise associated with system, which enhances
optomechanical features beyond the previous investigations.
Our findings are testable in a realistic setup and provide
foundations to manipulate SO-coupled topological states in thefield of quantum optics and quantum computation. (References:
1. Kashif Ammar Yasir & Wu-Ming Liu, Tunable bistability inHybrid Bose-Einstein condensate optomechanics, Sci. Rep. 5,10612 (2015). 2. Kashif Ammar Yasir & Wu-Ming Liu, Controlled
Electromagnetically Induced Transparency and Fano Resonancesin Hybrid BEC-Optomechanics, Sci. Rep. 6, 22651 (2016). 3. Kashif
Ammar Yasir & Wu-Ming Liu, Cavity-Optomechanics with SpinOrbit Coupled Spinor Bose-Einstein Condensate, arXiv:1511.01109[quant-ph]). )10029-31, Session 6

Power dependence on the nonlinear
interaction enhancement in a coherentlyexcited microcavity
Samuel Serna, Institut d’Électronique Fondamentale(France) and Lab. Charles Fabry (France) and Univ.
Paris-Saclay (France); Marc Hanna, Lab. Charles Fabry(France) and Institut d’Optique Graduate School (France)and Univ. Paris-Saclay (France); Xavier Le Roux, Institutd’Électronique Fondamentale (France) and Univ. ParisSaclay (France); Philippe Delaye, Institut d’Optique
Graduate School (France) and Lab. Charles Fabry (France)and Univ. Paris-Saclay (France); Eric Cassan, Institutd’Électronique Fondamentale (France) and Univ. ParisSaclay (France); Nicolas Dubreuil, Institut d’Optique
Graduate School (France) and Lab. Charles Fabry (France)and Univ. Paris-Saclay (France)
One of the advantages of photonic crystal microcavities is tostrengthen the interactions between an incident beam and thecavity material. This reinforcement, which is accompanied by
nonlinear index or loss/gain changes in the cavity limits theamount of energy that is coupled into the effective cavity mode.
Index variations caused by non-linearities, shift the resonancefrequencies precluding the coincidence with the excitation signal
frequency, thereby decreasing the injection efficiency.
In order to maintain the benefit of light localization throughout
the pulsed excitation, we have experimentally and numericallystudied the behavior of a silicon nanobeam cavity excited bydifferent power tailored chirped pulses whose spectral phaserelation compensates for the nonlinear frequency drift of thecavity resonance. Even though the coherent excitation technique
is currently used to control light-matter interactions in atomic
and molecular systems, its transposition to optical resonators
has been only subject of theoretical studies. Our results
represent the first experimental demonstration of enhancing
nonlinear interactions in a coherently excited integrated siliconcavity [Serna et al. Optics Express 23.23 (2015)]. Our numericalsimulations based on a coupled mode theory are in good
agreement with our experimental results. They also illustrate thecapability to manipulate the nonlinear dynamics of a cavity bymeans of a coherent excitation, which can be applied to more
complex structures like coupled cavities. Furthermore, we reporta deeper understanding on this dependency and provide insights
for system optimization such as materials, quality factors, input
powers and required compensation chirp.

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SPIE Photonics Asia·

10029-32, Session 7

Strong-field double ionization ofhydrocarbon molecules (Invited Paper)
Jian Wu, Xiaochun Gong, Qingying Song, Qinying Ji, Kang
Lin, Webin Zhang, Junyang Ma, Peifen Lu, Heping Zeng,
East China Normal Univ. (China)
Driven by strong laser fields, multiple electrons can eject fromatoms and molecules in either tunneling or multiphoton ionization
regions. As compared to the tunneling regime of ionization where
the electron escapes to the continuum through the laser field
suppressed potential barrier, the above-threshold ionization in
the multiphoton regime produces electron of discretized energy
by vertically absorbing many photons. Here, by measuring thethree-dimensional momenta of all ejected electrons and ionsin coincidence, we experimentally investigate the strong- field
double ionization of acetylene in both the multiphoton andtunneling regions.
In the multiphoton ionization region, as compared to thesequential process, diagonal lines in the electron-electron jointenergy spectrum are observed for the nonsequential abovethreshold double-ionization (ATDI) owing to the correlative
sharing of the absorbed multiphoton energies. In the tunnelingionization region, a molecule experiences significantly enhanced
ionization rate if the molecular axis is parallel to the field
vector, which is referred to as the electron localization-assisted
enhanced ionization.
Here, for the double ionization of acetylene using femtosecond
laser pulses, we resolve the molecular ATDI into distinct
channels and probe the electron-localization scenario in C-Hbond breaking in the multiphoton and tunneling ionization
regions, respectively. Our findings will shed some light on
the understanding and controlling of the rich multielectron
and nuclear dynamics of complex polyatomic, in particularhydrocarbon, molecules in strong laser fields.

10029-33, Session 7

Nonlinear photo-association spectroscopynear a narrow d-wave Feshbach resonance(Invited Paper)
Yuqing Li, Shanxi Univ. (China); Jizhou Wu, Sahnxi
University (China); Jie Ma, Shanxi Univ. (China); Liantuan
Xiao, Suotang Jia, Sahnxi University (China)
Some experimental and theoretical investigations havedemonstrated that enhanced photoassociation (PA) can beobtained near a Feshbach resonance. The PA near Feshbachresonance presents many potential applications, such as thegiant formation of ground cold molecules and the precision
measurement of some physical constants. In our work weconstruct a quantum interference in a three-level system, andfind a great nonlinear Fano effect in ultracold atom-molecule
coupled system. Ultracold Cs atoms, prepared by an optimized
degenerated three-dimensional (3D) Raman sideband cooling,
are loaded into a crossed optical dipole trap using magnetic
levitation technique. We have measured the effect of magnetic
field near a narrow d-wave Feshbach resonance on the rate,
stimulated line width of excited molecules and light-induced
frequency shift of a PA resonance in ultracold 133Cs atoms. We
have observed the nonlinear variation of PA rate with magnetic
field near the Feshbach resonance, where the asymmetric line
shape of PA rate results from quantum interference between
two competing PA processes from free-atom continuum state
and underlying bound d-wave Feshbach molecular state. The
broadening of stimulated PA line width and spectral shift of
PA are also strongly dependent on the magnetic field near the
Feshbach resonance, and show the dispersive changes thatwww.spie.org/pa·

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Conference 10029: Quantum and Nonlinear Optics IV

indicate the nonlinear Fano effect. The obtained suppressing ofbroadening of stimulated PA line width and enhancement of PA
spectral shift occur on the location of the minimum in PA rate. We
have developed a theoretical model to give a good agreementwith experimental results.

10029-34, Session 7

Quasi-phase matching in periodicallygrooved thin-film lithium niobate
waveguides
Xiao Xiong, Univ. of Science and Technology of China(China) and Harvard Univ. (United States); Cheng Wang,
Harvard Univ. (United States); Nicolas Andrade, Virginia
Commonwealth Univ. (United States) and Harvard Univ.
(United States); Vivek Venkataraman, Harvard School ofEngineering and Applied Sciences (United States); Xifeng
Ren, Guang-Can Guo, Univ. of Science and Technology
of China (China); Marko Loncar, Harvard School ofEngineering and Applied Sciences (United States)
Lithium niobate is an excellent second order nonlinear opticalmaterial that has been widely used in modern optics. Integrated
lithium niobate platform has recently emerged as a promising
candidate for next-generation wavelength conversion systems
that feature high conversion efficiency and allow mass
production. Here we demonstrate efficient second harmonic
generation in lithographically-defined thin film lithium niobate
waveguides. Both perfect phase matching in fixed-width
waveguides and quasi-phase matching in periodically-grooved
waveguides are theoretically proposed and experimentally
characterized. Our low-loss (~ 2.45 dB/cm) waveguides possess
normalized conversion efficiencies as high as 41% W-1cm-2, andare promising for future on-chip quantum wavelength conversion.

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241

Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
Wednesday - Friday 12–14 October 2016
Part of Proceedings of SPIE Vol. 10030 Infrared, Millimeter-Wave, and Terahertz Technologies IV

10030-1, Session 1

10030-3, Session 1

Terahertz radiation from nonlinear surface
plasmon polaritons in graphene (Invited
Paper)

Strong terahertz fields on the nanoscale:
Near-field streaking, electron control, andterahertz field emission (Invited Paper)

Chao Zhang, Univ. of Wollongong (Australia)

Georg Herink, Georg-August-Univ. Göttingen (Germany)

Understanding the optical properties of graphene and graphenenanostructures is of importance in the development of graphenebased optoelectronic devices. We have carried out a theoreticaland computation study of optical response of graphene over awide frequency range, from terahertz to ultraviolet. It is foundthat the optical response is highly anisotropic at high frequencies
and highly nonlinear in the terahertz to far-infrared regime. Dueto the nature of graphene’s nonlinear conductivity, both TE(transverse electric) and TM (transverse magnetic) modes aresupported on a graphene sheet. We demonstrate that, nonlinear
conductivity can the energy of surface plasmon polariton (SPPs)
in graphene. As a result dispersion of SPPs crosses the light line.
This gives rise to the possibility that SPPs can be transformed
to radiation by an electron beam moving at speed fast than
the speed of light in the dielectrics. This type of nonlinear SPPs
can induce an optical bistability in an air-graphene-dielectric
structure. Under a moderate electric field in the terahertz
frequency regime, the third nonlinear optical conductivity iscomparable to the linear conductivity. Both the energy andfrequency of the surface plasmon polaritons depend on thestrength of the nonlinear current in the graphene layer. Under
an opaque incident, the reflectance as a function of frequency
exhibits bistability. The origin of the bistability is the fielddependent plasmon mode. We have determined the parameter
regime for the occurrence of bistability in this structure.

Coupling light to metal surfaces can break the diffraction limit
and concentrate optical fields at the nanoscale. In this talk, I
will present recent results on the interaction of intense THzpulses with metallic nanotips. First, I will introduce a sub-cycle
interaction regime which is unique to nanostructures and strong,long-wavelength excitation. This is employed for THz nearfield streaking - a scheme that is implemented as a two-color
experiment at a single nanostructure. It allows to experimentally
map local THz-nearfield waveforms, e.g., to characterize theelectromagnetic response of nanostructures. Furthermore, thescheme allows for a control of electron motion on ultrafast
timescales. I briefly sketch new ultrafast instruments, which aredeveloped in our group, to image ultrafast dynamics at surfaces
and nanostructures. I will also present results on THz-induced
field emission and its application to map ultrafast non-equilibrium
carrier dynamics in nanostructures. Finally, I will discuss thepresented results in the light of novel nano-electronic devices
which enable the control of electron motion on ultrafast
timescales on the nanoscale.

Terahertz pulse generation from metal
nanoparticle ink (Invited Paper)
Kosaku Kato, Keisuke Takano, Yuzuru Tadokoro, Khoa T. N.
Phan, Makoto Nakajima, Osaka Univ. (Japan)

10030-2, Session 1

THz air photonics at micrometer scale(Invited Paper)
Xi-Cheng Zhang, Fabrizio Buccheri, Kang Liu, Univ. ofRochester (United States)
Micrometer size laser induced plasma is generated by focusinga laser beam with microscope objectives with high numericalaperture (NA). The THz emission pattern is off from the opticalbeam propagation direction. We have measured THz emission
with the laser pulse energy less than a micro joule. We also report
the recent study of THz wave sensor using micro-plasma.

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10030-4, Session 1

SPIE Photonics Asia·

Terahertz pulse generation from metallic nanostructures
irradiated by femtosecond laser pulses is of interest because
the conversion efficiency from laser pulses to terahertz waves
is increased by the local field enhancement resulting from theplasmon resonance. In this talk we present our recent study on
terahertz generation from metal nanoparticle ink. We baked
a silver nanoparticle ink spin-coated onto a glass coverslip
in various temperatures. Observation by an atomic force
microscope revealed that on the surface of the baked ink bumpy
nanostructures are spontaneously formed, and the average sizeof bumps depends on the baking temperature. These structures
are expected to lead to local field enhancement and then large
nonlinear polarizations on the surface. The baked ink was
irradiated by regeneratively amplified Ti:sapphire femtosecond
laser pulses at an incidence angle of 45 degrees. Waveformsof generated terahertz pulses are detected by electro-opticalsampling. The generation efficiency was high when the average
diameter of bumps was around 100 nm, which is realized
when the ink is baked in 205 to 235 degrees centigrade in
our setup. One of our next research targets is terahertz wave
generation from micro-patterned metallic nanoparticle ink. It isan advantage of the metal nanoparticle ink that by using inkjet
printers one can fabricate various patterns with micrometerscales, in which terahertz waves have a resonance. Combinationof microstructures made by a printer and nanostructure
spontaneously formed in the baking process will provide us
terahertz emitters with unique frequency characteristics.

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-5, Session 1

Homogeneous broadband terahertz
quantum cascade lasers (Invited Paper)
Hua Li, Jun-Cheng Cao, Shanghai Institute of Microsystem
and Information Technology (China)
The terahertz quantum cascade laser (QCL) is the unipolar
emitting device based on the electron intersubband transitionsin the multiple-quantum-well active region. Among all theelectrically pumped semiconductor lasers, the terahertz QCL
shows the highest performance in the frequency range between
1 and 5 THz. Followed by the fast development of frequency
combs in the visible and infrared wavelengths, the researchon terahertz QCL-based broadband combs has attracted wide
interest.
In this work, we employ an active region structure combining
the bound-to-continuum and resonant-phonon designs. The
molecular beam epitaxy-grown wafer is processed into single
plasmon waveguide ridge lasers. At the low temperature of 10
K, the fabricated lasers show ultralow threshold current density
around 60 A/cm2 in the continuous wave (cw) mode. We
systematically investigate the electrical inter-mode beat note of a
6-mm long cavity QCL and its eye diagram to show the stabilityof the laser longitudinal modes. Since the inter-mode beating
frequency is the result of the mixing between the adjacentlongitudinal modes and the frequency falls in the radio frequency(RF) range, the laser can be modulated with the external RF
signal. With RF modulation, we finally observe a homogeneously
spectral spanning of 320 GHz which continuously covers the
spectral range from 4.01 to 4.33 THz. The modes are evenly
spaced by the external RF frequency at 6.1 GHz. The homogenous
emission spectra can be used for spectroscopic applications witha spectral resolution of few GHz. As examples, we use the longcavity QCL to measure the transmission of a GaAs etalon sample
and the oscillation feature in the transmission can be clearlyobserved; we also show that the QCL can be used to identify NH3
gas by measuring the spectra around 4.2 THz and the measured
results show good agreement with the HITRAN data.

10030-6, Session 2

Electro-optic sampling detection of
THz pulses based on Cherenkov phasematching (Invited Paper)
Masahiko Tani, Takeshi Furuya, Hideaki Kitahara, Univ.
of Fukui (Japan); Elmer S. Estacio, Univ. of Philippines
Diliman (Philippines); Kazuyoshi Kurihara, Kohji
Yamamoto, Daiki Gotoh, Takuro Yasumoto, Univ. of
Fukui (Japan); Takashi Notake, Hiroaki Minamide, RIKEN(Japan); Michael I. Bakunov, N.I. Lobachevsky State Univ.
of Nizhni Novgorod (Russian Federation)
For detection of pulsed terahertz (THz) pulsed radiation, theelectro-optic (EO) sampling detection technique is commonlyused as well as the photoconductive sampling. Recently, we havedemonstrated the non-collinear EO sampling detection of THz
pulsed radiation based on the Cherenkov-phase matching. The
advantage of it is relaxation of the velocity matching condition
between THz waves and optical sampling waves. Based on the
Cherenkov-phase matching, we have developed the “heterodyne
EO sampling”, where the EO sampling signal is observed as
the direct intensity changes in the probe beam without using
any polarization optics. The advantages of the heterodyne EO
sampling compared to the ordinary ellipsometric EO sampling are
the simplicity in the optical detection system and its applicability
to birefringent EO crystals, for which a complicated optics are
required for compensation of the intrinsic phase-retardation due

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Follow us on:to the birefringence. An interesting feature of the heterodyne EO
sampling is its spatial distribution of the EO sampling signal overthe probe beam cross section. Corresponding to the difference
and sum frequency generation, we observe polarity reversed
EO signal in each half of the probe beam cross section and thesignal maxima are observed at points near the edge of the probebeam. In this paper, we review the advantages and propertiesof the electro-optic sampling detection of THz pulses basedon Cherenkov phase-matching, showing several experimental
measurements as examples.

10030-7, Session 2

Broadband high-power terahertz radiationfrom laser-produced plasmas (Invited
Paper)
Zheng-Ming Sheng, Shanghai Jiao Tong Univ. (China) andUniv. of Strathclyde (United Kingdom); G. Q. Liao, W. M.
Wang, Institute of Physics (China); W. J. Ding, A*STAR
Institute of High Performance Computing (Singapore); Z.
L. Zhang, Yanping Chen, Min Chen, Shanghai Jiao Tong
Univ. (China); Y. T. Li, Institute of Physics (China); Jie
Zhang, Shanghai Jiao Tong Univ. (China)
The interaction of ultrashort intense laser pulses with plasmas
either at gas or solid densities is promising to produce
broadband terahertz (THz) radiation with the highest peak
power. Recent progressesboth in theoretical and experimental
studies on this problem will be presented. In the interaction of
intense lasers with a solid target, it is shown that the large fluxof hot electrons with charge of a few nC per pulse can lead to
THz radiation via coherent transition both in the front and at
the rear side of the solid target. Terahertz field strength as highas sub GeV/cm is illustrated in numerical simulation. When alarge preplasma is formed in front of a solid target, it is shownthat THz radiation can be produced via linear mode conversion
from electron plasma wave excitation. With gas targets, thetwo-color laser scheme for THz radiation due to field ionization
currents has been investigated for a wide range laser and gas
parameters, including the laser wavelength, laser intensity, pulse
duration, relative phase of the two lasers, and gas species. Our
experimental results are supported by theory models.

10030-8, Session 2

High-sensitive THz superconducting hot
electron bolometer mixers and transitionedge sensors (Invited Paper)
Wen Zhang, Purple Mountain Observatory (China); Wei
Miao, Kangmin Zhou, Jiaqiang Zhong, ShengCai Shi,
Purple Mountain Observatory (China) and Key Lab. ofRadio Astronomy (China)
Terahertz band, which is roughly defined as 0.1 THz to 10 THz, isan interesting frequency region of the electromagnetic spectrum
to be fully explored in astronomy. THz observations play key
roles in astrophysics and cosmology. High sensitive heterodyne
and direct detectors are the main tools for the detection ofmolecular spectral lines and fine atomic structure spectral lines,
which are very important tracers for probing the physical andchemical properties and dynamic processes of objects suchstar and planetary systems. China is planning to build an THz
telescope at Dome A, Antarctica, a unique site for ground-based
THz observations. We are developing THz superconducting hot
electron bolometer (HEB) mixers and transition edge sensors(TES), which are quantum limited and back-ground limited#PhotonicsAsia

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
detectors, respectively. Here we first introduce the working
principles of superconducting HEB and TES, and then mainlypresent the results achieved at Purple mountain Observatory.

10030-9, Session 2

THz and x-ray emission as a tool for studyof ionization dynamics in gas clusters(Invited Paper)
Alexei V. Balakin, M. S. Dzhidzhoev, V. M. Gorgienko, M.V.
Lomonosov Moscow SU (Russian Federation); Mikhail N.
Esaulkov, Institute on Laser and Information Technologies(Russian Federation); Irina A. Zhvania, M.V. Lomonosov
Moscow SU (Russian Federation); I. A. Kotelnikov, Budker
Institute of Nuclear Physics SB RAS (Russian Federation)
and Novosibirsk State Univ. (Russian Federation);
N. A. Kuzechkin, Institute on Laser and Information
Technologies (Russian Federation); Ilya A. Ozheredov,
Andrey B. Savel’ev, Artem Sidorov, Petr M. Solyankin,
M.V. Lomonosov Moscow SU (Russian Federation); M.
B. Smirnov, Russian Research Ctr. Kurchatov Institute(Russian Federation); Alexander Pavlovich Shkurinov,
M.V. Lomonosov Moscow SU (Russian Federation) andInstitute on Laser and Information Technologies (RussianFederation); Vladislav Ya. Panchenko, Institute on Laserand Information Technologies (Russian Federation)
Interactions of laser radiation with gas cluster targets have been
investigated in the past two decades. Cluster jet, obtained by the
adiabatic condensation of gas flow, has pronounced nonlinear
optical properties and combines the advantages of solid-stateand gas target. Cluster inherits high local density and this implies
high value of nonlinear response. At the same time cluster
beams are not exposed to ablation and renew their properties
before each act of interaction with the laser pulse. There
were observed and predicted various nonlinear effects during
interaction of intense laser pulses with cluster jets: generation of
X-ray radiation, generation of optical harmonics, self-focusing,Stimulated Raman Scattering. It was shown theoretically andexperimentally that absorption of laser radiation in cluster beam
can reach high value (up to 95%) which is related to linear (Mie)and nonlinear resonance interactions. Resonance absorption ofpulse energy results in efficient production of X-Ray and fast
charged particles. In this way, further studies of interaction of
intense laser pulses with clusters seems reasonable due to thepossibility of usage in various practical applications and solving
fundamental problems of behavior of matter under intense laser
fields.
In some recent publications, intense THz generation in cluster
beam excited by ultrashort laser pulses was reported. It wasobserved more than two orders of magnitude enhancementof THz pulse intensity in Ar cluster jet compared to that ingaseous Ar with equal average atomic density. With increasingof excitant pulse energy up to its maximum value of 70 mJ(corresponding to the vacuum intensity ~ 1017 W/cm2) THz pulse
energy increased by the square law without saturation. There wasreported in that the directivity pattern of terahertz radiation fromclustered plasma has four-lobed structure.
At the present moment there is no clear theoretical interpretationof the experimental results and complete understanding of themechanism of low-frequency emission in cluster plasma. It seems
reasonable to carry out further study of terahertz generation ina clustered plasma, and examine this process in both ways: asa fundamental issue of laser-matter interaction on the way tosolving a problem of the dynamics of laser-cluster interaction,
and as a practical goal of obtaining an effective source of

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SPIE Photonics Asia·

pulsed THz radiation. In addition, there is possible to apply
two-color excitation scheme, which has been successfully usedin the past to increase the efficiency of the optical to terahertz
conversion in laser-induced plasma of gas media. In this scheme,
the fundamental laser frequency at ? is mixed with its second
harmonic at 2?. Two-color scheme allows to increase THz yieldby 2…3 orders of magnitude and nowadays this scheme is widelyused for THz generation in gaseous media. Nevertheless, opticalto terahertz conversion efficiency in laser-plasma generation
method is still low [16]. In addition, there was observed asaturation of THz yield in a two-color scheme at high excitantpulse energy that originates from THz absorption in dense
plasma. Cluster target seems to be attractive to solve these
problems.
In this paper we present the results of experimental andtheoretical studies of generation of terahertz emission in thelaser-induced clustered plasma. We have performed experiments
using both single-color and two-color excitation schemes.
Simultaneously with the control of terahertz emission of clusteredplasma we measured the power of accompanying X-ray radiation,
which is an important source of information about the processes
that occur in a cluster plasma. In the theoretical section we madean attempt to explain the experimental results.

10030-10, Session 2

High-repetition-rate widely-tunableterahertz generation in GaSe pumped by adual-wavelength KTP-OPO
Dexian Yan, Degang Xu, Yuye Wang, Wei Shi, Kai Zhong,Pengxiang Liu, Chao Yan, Quan Sheng, Jialin Mei, Jia Shi,
Jianquan Yao, Tianjin Univ. (China)
We report a widely tunable terahertz source by using GaSe
crystals pumped by a walk-off compensated dual-wavelength
KTP OPO around 2.128 ?m, based on difference frequency
generation (DFG). The KTP OPO was intracavity pumped byan acousto-optical Q-switched side-pumped Nd:YAG laser withthe repetition rate of 10 kHz. The tunable THz radiation from 0.2
THz to 3 THz has been achieved in 8 mm GaSe crystal while thetuning range extended continuously from 2.057 ?m to 2.185 ?m.
The maximum output average power is reach ?W-level around1.48 THz.

10030-11, Session 2

THz-wave parametric oscillator with asurface-emitted ring-cavity configuration
Zhen Yang, Yuye Wang, Degang Xu, Longhuang Tang,
Chao Yan, Pan Duan, Wentao Xu, Tianjin Univ. (China)
The terahertz wave (THz wave), located at the boundary between
the microwave and optical bands, is of great interest for various
applications, such as imaging, molecular analysis, life science, andnondestructive evaluation. For many practical applications of THz
technologies, high-energy output and frequency-agile THz wave
sources with continuous tunability over a wide spectral range
are expected to improve the sensitivity, resolution, and speed ofmeasurement.
In this work, a surface-emitted ring-cavity terahertz (THz) wave
parametric oscillator has been demonstrated for high-energy
THz output and fast frequency tuning in a wide frequency range.
Through the special optical design with a Galvano optical scannerand four-mirror ring-cavity structure, a maximum THz output
of 12.9 ?J/pulse is achieved at 1.359 THz under the pump pulse
energy of 172.8 mJ with the repetition rate of 10 Hz. The beamcharacteristics are analyzed and optimized for this cavity. The M2

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
at horizontal and vertical directions is 1.64 and 2.51, respectively.
It is expected that this high-power THz-wave system with a finebeam profile can provide useful advantages and find numerous
applications in several areas.

10030-12, Session 2

Performance of a mm-wave adaptive
beam-formed phased array system forindoor communication
Kinnan Amjad, Huaping Xu, Beihang Univ. (China)
Millimeter waves (mmWaves) spectrum ranging from 30GhZ to
300Ghz is emerging as a potential solution to the bandwidth
problem faced by the wireless communication now a days.
The advancements in the antenna technology has enabled
the fabrication of antenna arrays or phased array systems
which when used with techniques like spatial multiplexing andbeamforming has enabled the use of mmWaves for both indoor
and outdoor communication systems by providing gain andselectivity. This has also opened the doors for its potential use
in long range and cellular communications. The 60GHz bandalso know as the oxygen absorption band due to its higher
attenuation and unlicensing is a good candidate for use in secureand confined communications. In this paper we have investigatedthe performance of a beamformed phased array system in themmWave spectrum. The performance is measured for varying
source and noise locations and for different array types.

10030-13, Session 3

Terahertz free-electron laser spectroscopyof excitons in III-V semiconductor
quantum wells and single quantum dots
(Invited Paper)
Harald Schneider, Helmholtz-Zentrum DresdenRossendorf e. V. (Germany); Daniel R. Stephan, Sabine
Zybell, Helmholtz-Zentrum Dresden-Rossendorf e. V.
(Germany) and TU Dresden (Germany); Stephan F.
Winnerl, Jayeeta Bhattacharyya, Helmholtz-Zentrum
Dresden-Rossendorf e. V. (Germany); Faina Esser, ManfredHelm, Helmholtz-Zentrum Dresden-Rossendorf e. V.
(Germany) and TU Dresden (Germany)
Using intense, spectrally narrow terahertz pulses from thefree-electron laser facility FELBE in Dresden, Germany, we haveinvestigated exciton population dynamics in III-V QWs and single
quantum dots (QD). To this end, carriers are optically injected bypicosecond near-infrared pulses to populate the lowest excitonic
level. Using narrowband terahertz pulses, excitons are resonantly
excited into higher levels. Time-dependent photoluminescence(TDPL) measurements based on a streak camera system and ontime-correlated photon counting, respectively, then allow us to
study the transient population of dipole-allowed higher exciton
levels and to access the relaxation dynamics.
In QWs, the most prominent transition is from the excitonic 1sground state into the 2p excited state (using hydrogen notation),
which rapidly scatters into the 2s state. TDPL originating fromthe 1s and 2s excitons thus provides a unique signature whichallows us to explore the relaxation dynamics involving 1s, 2s, and2p [1]. Now turning to QDs, single QDs rather than QD ensembles
should be investigated in order to prevent strong inhomogeneous
broadening. We have therefore developed a micro-TDPL setup
to become sensitive to one single QD [2]. In particular, weinvestigate the dynamics of the s-to-p inter-sublevel transition,
which occurs in the range 13-20meV for the QDs under study.

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Resonant terahertz excitation, about 0.7ns time delay after
interband excitation, causes an instantaneous reduction of theground state TDPL. The signal recovers within about 100ps
towards a value which depends on the near-infrared excitationenergy. In particular, qualitatively different behavior has been
observed and analyzed using a phenomenological rate equation
for interband excitation of the GaAs matrix, the InGaAs wetting
layer, and quasi-resonant QD excitation.
Acknowledgements: We thank L. Schneebeli, C.N. Böttge, M. Kira,and S.W. Koch (Marburg, Germany) for fruitful discussions andcollaboration.
[1] S. Zybell et al., Appl. Phys. Lett. 105, 201109 (2014)[2] D. Stephan et al., Appl. Phys. Lett. 108, 082107 (2016)

10030-14, Session 3

Trace amount liquids sensing by meansof near-field THz emission spectroscopy(Invited Paper)
Masayoshi Tonouchi, Osaka Univ. (Japan)
Considering biological application using terahertz (THz) waves in
the future, we have developed a nonlinear optical crystal (NLOC)-based THz micro-total analysis system (THz-?TAS) for measuring
trace amounts of liquids using THz waves. The THz-?TASs withand without metamaterials are fabricated on a 500-?m-thick(110)-oriented GaAs wafer by wet etching. We demonstrate todistinguish commercial mineral waters with a amount of several
100 nL (less than 60 femto mol) successfully.The metamaterials
consist of periodically-arranged a few meta-atoms (sprit-ringresonators with the diameter of 84?m) equipped with two gaps
and a micro-fluid channel. In the conference we report theirdesign, fabrication procedures, and sensitivity with and without
metamaterials.

10030-15, Session 3

High-conductivity mechanism ofconducting polymer PEDOT:PSS studied
by terahertz and infrared spectroscopy(Invited Paper)
Masatsugu Yamashita, Yusuke Yamada, Chiko Otani,
RIKEN (Japan)
PEDOT:PSS, one of the most commercially successful conducting
polymer, has attracted wide attentions from both academic
and technological aspects because of its excellent conductivity,transparency in visible region, high thermal stability coupled withthe merit of low cost wet-process. PEDOT has a pai-conjugatedchain and can deliver the charge carrier along its chain via?-orbital. The charge carriers are doped in PEDOT chain throughthe oxidative polymerization with the insulating PSS. The highly
conducting PEDOT:PSS film can be obtained by the additionof ethylene glycol (EG). XRD study captured the existenceof PEDOT nano-crystal which increase from 1 to 5 nm by theaddition of EG. On the other hands, AFM study clearly shows
the macroscopic changes in the film morphology due to theaggregation of PEDOT by the EG. However, it is not clear whether
the metallic state in PEDOT:PSS is realized or not.
In this study, we studied high conductivity mechanism ofconducting polymer PEDOT:PSS with the temperaturedependence of THz and infrared (IR) spectra. While IR spectra
show plasma reflection which has temperature independent
behavior, THz complex conductivity spectra shows thermally
activated and carrier localization behaviors. The localization
modified Drude model explains well the temperature dependence#PhotonicsAsia

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IVof the THz and IR spectra The results suggests the highconductivity of PEDOT:PSS is realized with an weak carrier
localization state where PEDOT nano-crystals aggregate to form
the disordered metallic conducting path.

10030-16, Session 3

Hiromichi Hoshina, RIKEN (Japan)
In this presentation, potential of the terahertz (THz) waves as a
new tool for polymer science will be discussed. In the first part,THz spectroscopy of polymers will be presented. Absorption
spectra of polymer reflect their higher-order conformation which
provides information about polymer crystallization, degradation
and water adsorption. We have succeeded to develop method forthe assignment of low-frequency vibrational modes of polymers
and obtained information of their higher-order conformations.
By the temperature dependent THz spectra, the change of thehydrogen-bond interaction and the structure of the polymers
during the phase transition were observed. In the second part,THz-wave manipulation of polymer structure will be presented,
in which we succeed in altering polymer morphology using THz
wave irradiation. We irradiate a poly(3-hydroxybutylate) (PHB)/ chloroform solution during cast crystallization using a THz
wave generated by a free electron laser (FEL). Morphologicalobservation shows the formation of micrometer-sized single
crystals via the THz wave irradiation. Further, a 10-20% increasein crystallinity is observed through analysis of the infrared (IR)absorption spectra. The power density of the irradiating THz
wave is 40 MW/cm2, which is significantly lower than the typicallaser intensities used for material manipulation.

10030-17, Session 3

A study of vibrational spectra of leucine
and isoleucine in terahertz domain

Amino acid isomers detection is useful for the quality control of
the food and pharmaceutical potency. Leucine and isoleucine
are homologous isomers. They have very similar molecular
structures, but different chemical and physical properties. To
distinguish different amino acid isomers, researchers commonlyuse gas chromatography, liquid chromatography, capillaryelectrophoresis, LC-MS, GC-MS etc. Those methods normallyneed sample preparation, which is time consuming anddestructive. Terahertz wave refers to the frequency in the 0.1-10
THz spectra of electromagnetic radiation and its wavelength is
between 0.03 to 3 mm. THz time domain spectroscopy (THzTDS) can provide the structure information of the material andconfiguration. Biological macromolecular terahertz absorption
are related with intermolecular hydrogen bond vibration androtational level about the dipole transition, and it can be used
for fingerprint identification of molecular dipole transition. In
the present the terahertz time-domain spectroscopy (THz-TDS)and Fourier transform infrared spectroscopy (FTIR) was used tomeasure the absorption spectroscopy of leucine and isoleucine
at room temperature. A number of different well-resolved THz
absorption peaks for the two components were observed, but
their infrared absorption peaks were almost overlapped. In
parallel with the experimental study, the computed vibrational
spectra were also obtained by using first principles calculations
based on the density functional theory (DFT). The theoreticalresults fit well with the experimental results.

·

The production of honey with high nutritional value is difficult tomeet the needs of the market in China, so that the authenticity
problem of honey with difficult identification and great economic
value highlights the certain limitations of the existing examination
methods to distinguish the inauthentic honey.
Considered the strong absorption of water and its low energy,
terahertz technique is promising in the food industry. Terahertz
technique is sensitive to water and has amount of information
about carbohydrates’ intermolecular interactions, causing
terahertz spectroscopy a potential technique to detect honeyquality.
We got the THz absorption coefficient spectra of Acacia honeywith different high-fructose-syrup content in attenuated totalreflection module, which from the bottom up represent thedifferent adulterated high-fructose-syrup content of honeyfrom 10% to 100%. The growth of THz absorption coefficient ismatched by an increasing of high-fructose-syrup.
We find that Acacia honey and high-fructose-syrup have different
content of fructose, glucose and water. Except for water sensitive
to terahertz, fructose and glucose as monosaccharide also haveabsorption in the terahertz band. Then we build a PLS modelfor high-fructose-syrup content in adulterating honey, findingthat RMSEC: 0.0375, RMSEP: 0.0449, RPD: 7.08, showing a goodprediction and training of PLS model.
This work shows that it was possible to determine high-fructosesyrup content of Acacia honey by terahertz technique. The
work here is only a feasibility study, and further studies using
considerably more samples are required before the developedmodel can be adopted.

10030-19, Session 4

Lijuan Huang, Xin Zhang, Guo Wang, Zhuoyong Zhang,
Capital Normal Univ. (China)

SPIE Photonics Asia

Feasibility study of determination of highfructose-syrup content of acacia honey byterahertz technique
Wen Liu, Yuying Zhang, Donghai Han, China Agricultural
Univ. (China)

Application of terahertz waves forpolymer science (Invited Paper)

246

10030-18, Session 3

Terahertz nonlinear interactions,spectroscopy, and coupled modes (Invited
Paper)Keith A. Nelson, Massachusetts Institute of Technology(United States)
Strong THz fields have been used to drive nonlinear responses inevery phase of matter. These include highly nonlinear responses
including phase transitions, chemical reactions, visible lightemission, and dramatic changes in electrical conductivity
and other material properties. A wide range of nonlinear THz
spectroscopy methods have been used including probing of THzinduced responses at frequency ranges from THz to hard x-rays.
2-dimensional THz spectroscopy has also been demonstrated onresonant responses including those of molecular rotations in thegas phase, driven by THz electric fields, and those of collective
spin excitations (magnons), driven by THz magnetic fields. Strong
coupling between THz fields and material excitations to form THz
polariton modes has been exploited for THz signal generation,
control, and visualization as well as THz spectroscopy. Recent
results including spectroscopy and interactions involving THz
electric and magnetic fields will be emphasized.

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-20, Session 410030-22, Session 4

Manipulating magnetic and opticalproperties of condensed matter withintense terahertz pulses (Invited Paper)

Removal of instrumental etalon
oscillations in broadband terahertz spectra
for accurate material characterization

Christoph P. Hauri, Paul Scherrer Institut (Switzerland)

Jindoo Choi, Jinwoo Lee, Kyung-Soo Kim, Soohyun Kim,
KAIST (Korea, Republic of)Laser pulses in the low-frequency Terahertz range (1-15 THz)with field strength up to several GV/m and several Tesla havebecome available only very recently. Such pulses offer novel
opportunities to explore ultrafast magnetization dynamics in a
regime differing from the commonly used optical lasers where
the magnetization control is mediated by heat deposition. We
show that strong THz fields allow coherent spin excitation even
without exciting a magnetic mode [1]. Our investigations on
the classical conducting ferromagnets (Fe, Co, Ni) unravel theonset of a co-existence of precessional motion and ultrafast
magnetization quenching as function of the THz field strength.
While the coherent precessional motion is induced by themagnetic field the concomitant electric field component give rise
to fast demagnetization.
Likewise we will show that intense Terahertz pulses propagating
in semiconductors can change the optical and electronic
properties on a sub-cycle timescale. As an example we will
present THz-assisted octave-spanning spectral broadening of anear IR femtosecond pulse by cross-phase modulation and an
advanced high-resolution 2-dimensional THz detector based onconventional silicon CCD technology [2].
1. C. Vicario et al. , Nature Photon. 7, 720 (2013)
2. M. Shalaby, C.P. Hauri, Nature Commun. 6:5976 doi: 10.1038/
ncomms6976 (2015)

10030-21, Session 4

Efficient structure resonant energy
transfer from EM waves to viruses for virus
inactivation (Invited Paper)
Chi-Kuang Sun, National Taiwan Univ. (Taiwan)
Recently we found that when confined acoustic vibrations
modifies the dipole moments of nanoparticles, incoming
electromagnetic waves oscillating at the same vibrationalfrequencies will resonantly couple with the confined acoustic
modes and result in terahertz photon absorption. Throught
the same prinicple, we recently observed the 3D acoustic
quantization mode in spherical viruses, which allows thestrong dipolar coupling with the resonant EM waves. Following
the previous findings, in this presentation, the efficiency ofenergy transfer from free-space electromagnetic wave to
confined acoustic vibrations in viruses is reviewed. Based ona damped mass-spring model, we established the relationshipbetween the displacement of vibrating viruses and theilluminated power of microwaves. We propose to define theefficiency of energy transfer from microwave to displacement
vibration through exploring the virus inactivation ratio. For
experimental verification, we studied the inactivation ratio of
Influenza A (H3N2) viruses in the phosphate buffer saline withdifferent microwave frequencies. The plaque assay study on
the inactivation ratio indicates high efficacy of the structure
resonance energy transfer from electromagnetic wave to
confined acoustic vibrations in spherical viruses. Our work notonly demonstrates the existance of the dipolar resonant modesof viruses with microwaves, but also establishes a model tofomulate the structure resonance energy transfer from EM wave
to confined acoustic vibrations in viruses. Above all, our study
can form the fundation to plan the future strategy to inactivate
airborne viruses in open space through microwave induced
confined acoustic vibrations.

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Terahertz time-domain measurements display various reflection
waves in the form of echo pulses, leading to oscillations in thefrequency domain. There are two origins for these multiple
reflections, one, the sample under investigation, and two,
optical components in the spectrometer setup. The echoes
produced from the sample provide meaningful supplementary
information about the sample, with which the determination
accuracy of the material parameters can be greatly enhanced.
Instrumental echoes on the other hand, do not possess suchvaluable information and only hinder accurate spectroscopic
analysis. Therefore, it is advantageous to selectively remove
these instrumental echoes, in which the sample-induced echoes
remain unaltered in the process. However, previous reports were
unsuccessful in addressing how to distinguish the two types of
echo signals, and hence, were only able to present algorithms
that remove these etalon effects altogether. In this work, wepoint out this important but often neglected aspect for accuratematerial characterization – the necessity of selective removalof only the instrumental etalon effect from terahertz spectra.
A signal processing algorithm is introduced, dedicated toeffectively eliminate only the instrumental echoes. Mathematicalderivation is presented, followed by several experimental resultsthat validate the proposed method. Application experiments
include water vapor absorption measurements, high-resistivity
silicon wafer characterization, and explosive pellet sample
evaluation. Results clearly show an effective and selective
removal of the instrumental etalon effect, ultimately presenting
highly accurate determination of material parameters.

10030-48, Session Post

A high-speed and low-noise intelligent
test system for infrared detectors
Tianshi Jia, Yulong Xue, Fansheng Kong, Shanghai
Institute of Technical Physics of the Chinese Academy of
Sciences (China)
With the development of infrared focal plane technology, thescale of the detector becomes larger and larger, and the pixel
noise level is lower and lower. Therefore, the rate and the noiselevel of the infrared measurement system are put forward. This
paper designed and implemented a set of infrared high-speed
low noise intelligent test system based on OPENVPX standard,
which is used to test the index, long term monitoring and lifeof infrared detector. OPENVPX architecture is far beyond the
VMEbus and CompactPCI architecture in transmission rate, board
level reinforcement, compatibility and other aspects. The system
is mainly composed of high speed back board, image acquisitionboard, temperature acquisition board and the main control board,which has high speed image acquisition, processing, temperaturemonitoring and alarm function. High speed backplane uses
full interconnection structure. RapidIO is used as the way ofdata transmission to ensure high-speed data transmission;
image acquisition board uses a 16 channel mode, each channel
consists of a low noise conditioning circuit and high precisionanalog to digital converter (ADC). Temperature measurement
board monitors the detector status in real time and has thewireless alarm function; As the control and processing core of
the system, the main control board is used to realize complex
algorithm. Differential amplifier and differential ADC are used
to achieve low noise, multi-channel high precision and low noise#PhotonicsAsia

247

Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
DAC achieves bias adjustable. Test results show that the system
noise is less than 100uV, the dynamic range reaches 100dB, andthe data throughput rate reaches 4Gbps, which can meet therequirements of the infrared detector test currently.

10030-49, Session Post

Investigation on terahertz generation fromzinc-blend crystal waveguide at polariton
resonance
Zhongyang Li, Silei Wang, Mengtao Wang, North China
Univ. of Water Resources and Electric Power (China)
Terahertz (THz) wave generation from zinc-blende crystal
waveguide, such as GaAs, InP, ZnTe and CdTe, at polariton
resonance region (PRR) with a transverse-pumping geometry
is investigated. It is shown that by using grating vector of
periodically inverted crystal THz wave can be efficiently
generated by difference frequency generation (DFG) with atransverse-pumping geometry. Parametric gain coefficient in the
low-loss limit and absorption coefficient of THz wave during DFG
process in the vicinity of PRR are analyzed. The frequency tuning
characteristics of THz wave via varying wavelength of difference
frequency waves and poling period of periodically inverted
crystal are numerically analyzed.

10030-51, Session Post

Oil spill detection using infrared
hyperspectral infrared camera
Hui Yu, Huazhong Institute of Electro-Optics (China)
and Wuhan National Lab. for Optoelectronics (China);
Zhen Zhang, State Oceanic Administration (China); Zhijie
Zhang, Huazhong Institute of Electro-Optics (China);
Song Yue, Hubei Jiuzhiyang Infrared System Co., Ltd.
(China); Chensheng Wang, Wuhan National Lab. for
Optoelectronics (China) and Huazhong Institute ofElectro-Optics (China)
Oil spill pollution is a severe environmental problem thatpersists in the marine environment and in inland water systems
around the world. Visual detection of an oil spill is not reliable
since oil on ocean environment is often confused with othersubstances, such as sea weeds, fish sperm etc. especially in the
low visibility condition, e.g. fog and darkness. Hyperspectral
imaging can be considered as a very reliable manner to detectand monitor oil spill on ocean environment. The hyperspectral
images can not only provide the space information but also thespectral information. Pixels of interests generally incorporate
information from disparate component that requires quantitative
decomposition of these pixels to extract desired information. Oil
spill detection can be implemented by applying hyperspectral
camera which can collect the hyperspectral data of the oil. By
extracting desired spectral signature from hundreds of band
information, one can detect and identify oil spill area in vastgeographical regions. There are now numerous hyperspectral
image processing algorithms developed for target detection.
In this paper, we proposed a target detection algorithm for theidentification of surface oil spills in ocean environment. The
proposed method mainly contains three steps: the first stepis the preprocessing method which is used to de-noise theacquired hyperspectral images; the second step is to abstract thefeatures of spectral data; and the second step is to detect theoil by using the target recognition method. In the experiments,
we applied a hyperspectral camera to collect the real life oilspill. The experimental results shows the feasibility of oil spilldetection using hyperspectral imaging and the performance ofhyperspectral image processing algorithms were also validated.
248

SPIE Photonics Asia·

10030-52, Session Post

Analyzing terahertz time-domaintransmission spectra with multi-beaminterference principle
Maorong Wang, Kai Zhong, Degang Xu, Yuye Wang, Wei
Shi, Jianquan Yao, Tianjin Univ. (China)
In the past decade, terahertz time domain spectroscopy
has become a powerful technique for measuring the opticalconstants of materials in a wide terahertz range. As is known,
this technique is based on recording the time-dependent electricfield of a terahertz pulse. The ratio of the Fourier transforms of
the electric field data recorded with and without the sample
yields the complex transmission coefficient of the sample in thefrequency domain. As to a huge number of transparent materials
such as thin-film dielectrics or semiconductors, remarkable
Fabry-Perot echoes in the time domain or transmittanceoscillations in frequency domain caused by multiple reflection
can be observed, which will be cut out during data processing
but that should lose some useful information. Here we present an
accurate analyzing method based on multiple beam interference
and Fresnel’s formula that extract simultaneously the refraction
index and the extinction coefficient from terahertz time domain
spectroscopy transmission spectra with oscillations, which are
the basis for calculating permittivity. Typical THz-TDS system
worked in transmission mode is utilized for direct measurementof the transmission spectra with a frequency accuracy of 7.6
GHz and range from 0.3 THz to 3 THz at room temperature. Thismethod is verified with a polished 350 ?m 100-cut GaAs wafer,and the reasonable average relative error for refractive index in
the whole range is less than 0.36% comparing with conventional
method, which provides a new approach to process the originaltransmission spectra with oscillations.

10030-53, Session Post

A novel wavefront-based algorithm fornumerical simulation of quasi-opticalsystems
Xiaoling Zhang, Purple Mountain Observatory (China)
and Key Lab. of Radio Astronomy (China) and Shanghai
Normal Univ. (China); Zheng Lou, Purple Mountain
Observatory (China) and Key Lab. of Radio Astronomy(China); Jie Hu, Purple Mountain Observatory (China)
and Key Lab. of Radio Astronomy (China) and Chinese
Academy of Sciences (China); Kangmin Zhou, Yingxi Zuo,
Shengcai Shi, Purple Mountain Observatory,CAS (China)
and Key Lab of Radio Astronomy, CAS (China)
This paper proposes a novel wavefront-based algorithm forthe beam simulation of both reflective and refractive optics
in quasi-optical system. The algorithm can be regarded as
the extension to the conventional Physical Optics algorithm
to handle dielectrics. Internal reflections are modeled in an
accurate fashion, and coating and lossy materials can be treatedin a straightforward manner. A parallel implementation of thealgorithm has been developed and numerical examples showthat the algorithm yields sufficient accuracy by comparing withexperimental results, while the computational complexity ismuch less than the full-wave. The algorithm offers an alternative
approach to the modeling of quasi-optical system in addition to
the Geometrical Optics modeling and full-wave method.

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-54, Session Post

10030-56, Session Post

Cost-effective bidirectional digitizedradio-over-fiber systems employing sigma
delta modulation

FPGA design large-area array infrared
detector video processing circuit of
infrared camera

Kyung Woon Lee, Korea Univ. (Korea, Republic of);
HyunDo Jung, Electronics and Telecommunications
Research Institute (Korea, Republic of); Jung Ho Park,
Korea Univ. (Korea, Republic of)

Tao Liu, China Academy of Space Technology (China)

We propose a cost effective digitized radio-over-fiber (DRoF)
system employing a sigma delta modulation (SDM) and abidirectional transmission technique using phase modulated
downlink and intensity modulated uplink. Delta-sigma modulationis transparent to different radio access technologies andmodulation formats, and more suitable for a downlink of wirelesssystem because a DAC can be avoided at the base station(BS).
Also, Central station and BS share a same light source by using aphase modulation for the downlink and an intensity modulation
for the uplink transmission. Avoiding DACs and light sources haveadvantages in terms of cost reduction, power consumption, andcompatibility with conventional wireless network structure.
We designed cost effective bidirectional DRoF system using
low pass SDM and measured downlink and uplink transmission
performance in terms of error vector magnitude, signal spectra,
and constellations, which are based on the 20MHz LTE 64-QAM
standard.

10030-57, Session Post

Active terahertz wave imaging system fordetecting hidden objects
Yuner Gan, Beijing Institute of Technology (China)

10030-55, Session Post

Infrared image segmentation method
based on interest point detection andsuperparamagnetic clusteringSongtao Liu, Ning Jiang, Zhenxing Liu, Dalian Naval
Academy (China)
The advantages of superparamagnetic clustering include that:(1) the clustering data does not make any assumptions; (2) the
number of clusters is not required and the initial conditions
are robust; (3) the parameters are fewer and adaptable; (4)the clusters of different shapes, sizes and densities can befound; (5) it has the global optimality, therefore, when the
superparamagnetic clustering is applied to infrared image
segmentation directly, the results are satisfactory and stable, but
the algorithm’s computation time is slightly long. In this paper,
after interest point detection and description, superparamagnetic
clustering is used for image segmentation, which overcomes
the deficiency of the traditional superparamagnetic clustering
method. Considering that the detector based on the directionof the edge is more robust to intensity changes and backgroundclutter, the edge foci points are used as interest points, which
are points in the image that are roughly equidistant from edges
with orientations perpendicular to the point. This detector has
three stages. First, locally normalized edge magnitudes andorientations are computed. Second, orientation dependent
filtering on the resulting edges is performed, and their results
are aggregated. Finally, local maxima in the resulting aggregatedfilter responses in both spatial position and scale is found. Whendescribing the interest points, the intensity order pattern is used.
The basic principle is that the relative order of pixel intensities
remains unchanged when the intensity changes are monotonic.
Specifically, a local intensity order pattern is adopted to encode
the local ordinal information of each pixel. This descriptor isinvariant to rotation and intensity changes. In conclusion, themain feature of this novel method is the combination of theinterest point detection and superparamagnetic clustering,which not only ensures the effectiveness of infrared image
segmentation, but also improves the efficiency of the clustering
algorithm.

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Satellite infrared camera to achieve a large-array imaging
infrared detectors, this paper analyzes the characteristics oflarge-array infrared detectors, equipment work environment,
miniaturization, signal sampling precision and high-speed serial
data transmission, using a clock management chip clock network
design, improved signal sampling accuracy and improve thereliability of high-speed serial data transmission; the use of signal
processing to achieve orbit correction channel inconsistencies
and improve the signal to noise ratio of the image; the useof electronic current limiter prevent single event latch-madedevices, the device improves reliability; ground adaptive pixel
correction, programmable blind yuan replace experiments in orbit
for future applications of the technology experiment, from theinfrared imaging camera location imaging results It can be seenon the design ideas and feasible and meets mission requirements.

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Terahertz wave can penetrate the common dielectric materials
such as clothing, cardboard boxes, plastics and so on. Besides thephoton energy of the terahertz wave is low, and does not cause
ionization, which is especially suitable for the safety inspection of
the human body. Terahertz imaging technology has a tremendous
potential in the field of security inspection at stations, airports
and other public places. Terahertz wave imaging system isdivided into two categories: active terahertz imaging system andpassive terahertz imaging system. So far, most terahertz imaging
system works at point to point mechanical scan pattern withthe method of passive imaging. The imaging effect of passive
imaging tend to have low contrast and the image is not clear
enough. This paper designs and implements an active terahertz
wave imaging system combining terahertz wave transmitting andreceiving with a Cassegrain antenna. The terahertz wave at thefrequency of 94GHz is created by impact ionization avalanchetransit time (IMPATT) diode, focused on the feed element for
Cassegrain antenna by high density polyethylene (HDPE) lens,and transmitted to the human body by Cassegrain antenna. The
reflected terahertz wave goes the same way it was emitted backto the feed element for Cassegrain antenna, focused on the hornantenna of detector by another high density polyethylene lens.
The scanning method is the use of two-dimensional planar mirror,
one responsible for horizontal scanning, and another responsible
for vertical scanning. Our system can achieve a clear human body
image, has better sensitivity and resolution than passive imaging
system, and costs much lower than other active imaging systemin the meantime.

#PhotonicsAsia

249

Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-58, Session Post

10030-60, Session Post

Terahertz liquid sensor

Identification of four kinds of rheum
which was gained by means of different
processing methods

Jing Liu, Beijing Institute of Technology (China); Jian Zuo,
CunLin Zhang, Capital Normal Univ. (China)
We demonstrate a novel method to identify liquid such as HCl
and NaCl by terahertz sensor in this paper. When certain liquid is
added to the gap of sensor, the electromagnetic response peakshifts towards red. Different liquid can be distinguish clearly bycomparison of different levels of the red-shifts. The simulation
results show that it is a sensitive method to detect different
substances in terahertz band.

10030-59, Session Post

Widely-tunable terahertz parametricoscillator based on MgO-doped nearstoichiometric LiNbO3 crystal
Longhuang Tang, Yuye Wang, Degang Xu, Zhen Yang,
Chao Yan, Wentao Xu, Pan Duan, Yixin He, Jia Shi, Meitong
Nie, Jianquan Yao, Tianjin Univ. (China)

Compact high-repetition-rate terahertz
source based on difference frequency
generation from an efficient 2-um dualwavelength KTP OPO

In this study, we proposed a wider tunable, high energy output
TPO based on MgO-doped near-stoichiometric LiNbO3 (SLN)
crystal, which was pumped by 1064 nm nanosecond pulsed laser.
The tunability was in the range of 1.2-4.7 THz. The maximum THz
wave output energy was 14.6?J/pulse at 2.19 THz under the pumpenergy of 165 mJ/pulse, corresponding to the maximum THz
wave conversion efficiency of 8.8?10-5 and the maximum photon
conversion efficiency of 3.8?10-3, respectively. Moreover, under
the same experimental conditions, the THz tuning range was
0.8-2.6 THz with MgO-doped congruent LiNbO3 (CLN) crystal. It
is demonstrated that the TPO had better performance with SLN
crystal than that with CLN crystal.

SPIE Photonics Asia·

Recent along with organism high-tech in traditional Chinese
medicinal materials study domanial use, rheum study all themore go deep into, all the more systematization. Rheum is oneof the most commonly used traditional Chinese medicine. Due tothe different processing methods, the drug efficacy of rhubarb
will be different. The absorption spectra of rheum with threedifferent processing methods can be gained by far-infrared
Fourier-transform infrared spectrometer (Far-infrared FTIR)
and terahertz time-domain spectroscopy (THz-TDS). By meansof comparing the discrepancies of spectra of three rheum, it isfound that the positions of their vibration absorption peaks are
distinctly different. On the other hand, the refractive index of
cooked rheum is the largest, followed by rheum and the minimum
is wine processing rheum. Three kinds of rheum can be identified.
In addition, the properties of traditional Chinese medicine will be
discussed in greater depth by using these methods.

10030-61, Session Post

The terahertz wave (THz wave), connected the microwave
region and the infrared region, has a great potential in various
applications, such as biomedical imaging, security andnondestructive evaluation. For many practical applications of
THz technologies, terahertz parametric oscillator (TPO),using
nonlinear crystal such as LiNbO3 and KTP crystal, has been
demonstrated as a promising THz source for its possessing theadvantages of widely tunable ,high energy output and room
temperature operation.

250

Lei Xu, Capital Normal Univ. (China)

Jialin Mei, Kai Zhong, Maorong Wang, Pengxiang
Liu, Degang Xu, Yuye Wang, Wei Shi, Jianquan Yao,
Tianjin Univ. (China); Robert A. Norwood, Nasser N.
Peyghambarian, The Univ. of Arizona (United States)
A compact optical terahertz (THz) source was demonstrated
based on an efficient high-repetition-rate doubly resonant
optical parametric oscillator (OPO) around 2 ?m with two typeII phase-matched KTP crystals in the walk-off compensatedconfiguration. The KTP OPO was intracavity pumped by an
acousto-optical (AO) Q-switched Nd:YVO4 laser and emitted
two tunable wavelengths near degeneracy. The tuning range
extended continuously from 2.068 ?m to 2.191 ?m with amaximum output power of 3.29 W at 24 kHz, corresponding
to an optical-optical conversion efficiency (from 808 nm to 2?m) of 20.69%, believed to be among the highest reported. The
stable pulsed dual-wavelength operation provided an ideal pumpsource for generating terahertz wave of micro-watt level by thedifference frequency generation (DFG) method. A 7.84-mmlong periodically inverted quasi-phase-matched (QPM) GaAs
crystal with 6 periods was used to generate a terahertz wave, themaximum voltage of 180 mV at 1.244 THz was acquired by a 4.2K Si bolometer, corresponding to average output power of 0.6?W and DFG conversion efficiency of 4.32?10-7. The acceptancebandwidth was found to be larger than 0.35 THz (FWHM). As toan 8-mm-long GaSe crystal used in the type-II collinear DFG, atunable THz source ranging from 0.503 THz to 3.865 THz withthe maximum output voltage of 154 mV at 1.85 THz would beachieved, and the corresponding average output power and DFG
conversion efficiency were 0.5 ?W and 3.6?10-7 respectively. This
provides a potential practical palm-top tunable THz sources for
portable applications.

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-62, Session Post

10030-64, Session Post

The properties of electromagnetic
responses and optical modulation interahertz metamaterials

Wavelength scaling of terahertz
generation via two-color photoionizationin pre-formed plasma

Wei Chen, Beijing Institute of Technology (China) andNational Space Science Ctr., CAS (China); Yulei Shi, Wei
Wang, Qingli Zhou, Cunlin Zhang, Capital Normal Univ.
(China)Suxia Huang, Hang Zhao, Cunlin Zhang, Liang-liang
Zhang, Capital Normal Univ. (China)

Metamaterials with subwavelength structural features show
unique electromagnetic responses that are unattainable withnatural materials. Recently, the research on these artificial
materials has been pushed forward to the terahertz (THz) region
because of potential applications in biological fingerprinting,security imaging, and high frequency magnetic and electricresonant devices. Furthermore, active control of their properties
could further facilitate and open up new applications in termsof modulation and switching. In our work, we will first present
our studies of dipole arrays at terahertz frequencies. Then inexperimental and theoretical studies of terahertz subwavelength
L-shaped structure, we proposed an unusual-mode current
resonance responsible for low-frequency characteristic dip intransmission spectra. Comparing spectral properties of ourdesigned simplified structures with that of split-ring resonators,
we attribute this unusual mode to the resonance coupling andsplitting under the broken symmetry of the structure. Finally,
we use optical pump–terahertz probe method to investigate
the spectral and dynamic behaviour of optical modulationin the split-ring resonators. We have observed the blue-shift
and band broadening in the spectral changes of transmission
under optical excitation at different delay times. The calculated
surface currents using finite difference time domain simulation
are presented to characterize these resonances, and the blueshift can be explained by the changed refractive index andconductivity in the photoexcited semiconductor substrate.

10030-63, Session Post

Wavelength scaling of terahertz radiationin plasma gas targets
Hang Zhao, Suxia Huang, Cunlin Zhang, Liang-liang
Zhang, Capital Normal Univ. (China)
In our experiments, terahertz radiation via two-color generated
laser plasma gas targets is studied using nitrogen and thenoble gases (helium, neon, argon, krypton, and xenon) as thegeneration media. Carried out at the infrared beam line of theadvanced laser light source, we studied the effects of different
pump wavelengths ?between 1200 nm and 1600nm?on THz
generation. Terahertz pulse energy and power spectra aremeasured as function of input pulse energy , gas species, gaspressure, and 5 different pump wavelengths between 1200
nm and 1600nm delivered by a commercial optical parametricamplifier (TOPAS). The experimental results show that theterahertz output pulse energy has a regular change with thedifferent variables.

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For the further fundamental understanding of the mechanism of
the THz wave generation in laser-induced plasma, the generationof terahertz radiation using an effective wavelength scalingmechanism is examined when two-color laser fields are mixed
in pre-formed plasma created by another 800nm laser pulse. In
our experiment, the effect of pre-formed plasma is investigatedusing an orthogonal pumping geometry. With a pre-formed
plasma, the THz yield is reduced significantly, and the radiatedTHz modulation changes regularly as a function of increasing
pump wavelength. Possible mechanism of the result is discussed
in terms of tunneling ionization in the terahertz generation
mechanism.

10030-65, Session Post

Chirped distributed Bragg reflector forbroadband group velocity dispersion
compensation in terahertz quantum
cascade lasers
Chao Xu, Dayan Ban, Univ. of Waterloo (Canada)
We present a theoretical study on designing and optimizinga chirped distributed Bragg reflector (DBR) to achieve groupvelocity dispersion compensation over an ultra wide frequency
range from 2 THz to 4 THz in metal-metal waveguides. A onedimensional (1D) model based on transfer matrix method is firstly
adopted to reveal the fundamental behaviors and characteristicsof the chirped DBR structures. Then a more accurate threedimensional (3D) model is deployed by using a COMSOL RF
package to verify the 1D simulation results and finalize the DBR
structure. The simulation results show that the design parametersof the DBR structures, such as the corrugation depth of the
chirped periods and the distribution profile of the period length,
play a critical role in determining how well the group velocity
dispersion is compensated. Substantial modulations in calculatedgroup delay curves emerge if the DBR structures are not properly
designed. These group delay modulations are related to GiresTournois interferometer effect, which is caused by the abrupt
interface between the waveguide sections with and without thechirped DBR. By including a buffer section between the two
waveguide sections to achieve a smooth transition in effective
refractive index, the group delay modulations can be significantly
minimized, yielding flat dispersion compensation over a wide
frequency range 2 THz to 4 THz in THz QCLs.

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251

Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-66, Session Post

correlation matched filter-based approaches such as spectral
signature matching and the spectral angle mapper.

A fast detection method for small weak
infrared target in complex background
Bo Lei, Wuhan National Lab for Optoelectronics (China)
and Huazhong Institute of Electro-Optics (China); Pu
Hong, Huazhong Institute of Electro-Optics (China) and
Wuhan National Lab. for Optoelectronics (China); Song
Yue, Hubei Jiuzhiyang Infrared System Co., Ltd. (China)
Observe from long distance, most targets appear to be weak andsmall, such as missile, aircraft and vehicle. However, for missile
guidance, locking the target in longer distance means more time
would be used to control the flight of the missile, thus morechance to hit the target; for menace warning, detect the target inlonger distance means more time to maneuver, thus more chance
to survive. This paper introduced a fast and effective method todetect small weak infrared target in complex background, which
is suitable for missile guidance and menace warning.
First, a template is created to detect the local maxima in theimage, which is regarded as seeds for the following region
growth. The current point whose gray value is much greater than
the average gray value of the neighbors in the template is marked
as local maxima.
Secondly, a constrained double criteria region growth algorithm
is performed to form separate regions. The region growth begins
from every seed, i.e. local maxima, and those points whose grayvalues are similar to and are adjacent to the seeds are determined
to be in the same region. Nevertheless, to avoid unnecessary
growth calculation in large regions, the growth is constrained bya given point number threshold.
Thirdly, extracted regions are selected by a small round target
filter, which filter out large regions and long regions that are not
likely to be targets. Those regions whose minimum enclosing
rectangles’ lengths are much longer than their widths are marked
as non-targets, and those regions which are constrained in region
growth are marked as non-targets because of their large areas.
Finally, a double check is performed to erase those regions where
there are other high gray value points in their neighbors.
Experimental results show the method introduced in this paper isfast and effective, which is suitable for the imbedded platform.

10030-67, Session Post

A new hyperspectral image classification
approach based improved similarity
measurement
Hui Yu, Pu Hong, Huazhong Institute of Electro-Optics(China) and Wuhan National Lab. for Optoelectronics(China); Song Yue, Hubei Jiuzhiyang Infrared System Co.,
Ltd. (China); Chensheng Wang, Huazhong Institute ofElectro-Optics (China)
Hyper-spectral images can not only provide spatial information
but also a wealth of spectral information. A short list of
applications includes environmental mapping, global change
research, geological research, wetlands mapping, assessmentof trafficability, plant and mineral identification and abundance
estimation, crop analysis, and bathymetry. A crucial aspect ofhyperspectral image analysis is the identification of materials
present in an object or scene being imaged.

In this paper, an improved hyperspectral images classification
algorithm is proposed. In the proposed method, an improved
similarity measurement method is applied, in which both thespectrum similarity and space similarity are considered. We
use two different weighted matrix to estimate the spectrum
similarity and space similarity between two pixels, respectively.
And then whether these two pixels represent the same material
can be determined. In order to reduce the computational cost the
wavelet transform is also applied prior to extract the spectral andspace features.
The proposed method is tested using hyperspectral imagery
collected by the National Aeronautics and Space Administration
Jet Propulsion Laboratory. Experimental results the efficiency ofthis new method on hyperspectral images associated with space
object material identification.

10030-68, Session Post

Hyperspectral image compressing using
adaptive band selection method
Zhijie Zhang, Wuhan National Lab. for Optoelectronics(China) and Huazhong Institute of Electro-Optics (China);
Hui Yu, Huazhong Institute of Electro-Optics (China)
and Wuhan National Lab. for Optoelectronics (China);
Zhen Zhang, State Oceanic Administration (China); Song
Yue, Hubei Jiuzhiyang Infrared System Co., Ltd. (China);
Chensheng Wang, Huazhong Institute of Electro-Optics(China)Hyperspectral imaging sensors can acquire images in hundredsof continuous narrow spectral bands. Therefore each object
presented in the image can be identified from their spectral
response. However, such kind of imaging brings a huge amountof data, which requires transmission, processing, and storage
resources for both airborne and space borne imaging. Due tothe high volume of hyperspectral image data, the exploration ofcompression strategies has received a lot of attention in recent
years. Compression of hyperspectral data cubes is an effective
solution for these problems. Lossless compression of thehyperspectral data usually results in low compression ratio, which
may not meet the available resources; on the other hand, lossy
compression may give the desired ratio, but with a significant
degradation effect on object identification performance ofthe hyperspectral data. Moreover, most hyperspectral datacompression techniques exploits the similarities in spectral
dimensions; which requires bands reordering or regrouping, tomake use of the spectral redundancy.
In this paper, we explored the spectral cross correlation between
different bands, and proposed an adaptive band selection
method to obtain the spectral bands which contain most of
the information of the acquired hyperspectral data cube. The
proposed method mainly consist three steps: the first step isto segment the spectral space into a series of sub-space; thesecond steps is to estimate the intrinsic dimension of sub-spacedata cube; the last step is to select the bands from the sub-space
by applying the wavelet-based method. The performance of the
proposed method was tested by using k-means classification
method.

Classification of a hyperspectral image sequence amounts
to identifying which pixels contain various spectrally distinct
materials that have been specified by the user. Several techniques
for classification of multi-hyperspectral pixels have been usedfrom minimum distance and maximum likelihood classifiers to

252

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-69, Session Post

Spectral radiance characteristic measuremethod based on passive imaging FTIR
spectrometer
Song Yue, Chensheng Wang, Wuhan National Lab. for
Optoelectronics (China); Pu Hong, Huazhong Instituteof Electro-Optics (China) and Wuhan National Lab. for
Optoelectronics (China); Bo Lei, Jiuzhiyang Infrared
System Co., Ltd. (China); Hui Yu, Huazhong Institute ofElectro-Optics (China) and Wuhan National Lab. for
Optoelectronics (China)
The spectral characteristics of infrared radiation from target
provide significant characteristics information for target’s
detection and track including radiance brightness, radianceintensity and spectrum characteristics of target. And the sametime, the spectral characteristics provide the basis of target
detection and recognize equipment’s waveband optimization
design and detection capability analysis. This paper using thepassive imaging Fourier transformation infrared spectrometermeasure the infrared spectral characteristic of target. The
spectral range cover the medium wave and long wave infrared.
And the instrument can interference imaging in 320?256 spatial
resolution or other window size. This paper designs a set ofcalibration and test processes to realize the infrared spectral
radiance measurement of target. The specific operating steps
are as follows: First of all, through the multiple points radiancecalibration, the radiance response characteristic of instrument isobtained. Secondly, the calibration result is applied in the spectral
test result of target scene to get the absolute infrared spectral
radiance curve. Then reducing the dimension of target spectrum
though principle component analysis can remove the interferenceof background and noise to abstract the characteristic
component of target to get the spectral radiance characteristic.
Using this method, this paper test some typical infrared target.
After the radiance calibration, the calibrated result is verified bystandard radiance source. Thereby, the remote measurement of
infrared background outdoors is taken as the comparison test.
Finally, the typical infrared target spectral features are extracted
and measured. The test results show that the method mentioned
in this paper is practical.

10030-71, Session Post

A fast pyramid matching algorithm for
infrared object detection based on region
covariance descriptor
Yin Lihua, Wang Xiao, Shanghai Institute of TechnicalPhysics of the Chinese Academy of Sciences (China)
In order to achieve the purpose of infrared target detection ,there are two phases?Feature Selection and Feature Matching.
Good Features should be discriminative, robust and easy tocompute. The matching strategy affects the accuracy andefficiency of matching. In the first stage, Instead of the joint
distribution of the image statistics, we use region covariancedescriptor and calculated region covariance using integral
images and the computational cost is independent of the sizeof the region. The covariance of 7-features, e.g., the one onedimensional intensity image, the norm of first and second
derivatives of intensity with respect to x and y., characterizes aregion of interest. The idea presented here is more general than
the image sums or histograms, which were already published
before. In the second feature matching stage, we describe a new
and fast pyramid matching algorithm under the distance metric,
which performed extremely rapidly than a brute force search. We
represent an object with five covariance matrices of the image

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Follow us on:features computed inside the object region. Instead of brute force
matching, we constructed the image pyramid and decomposed
the source image and object image into several levels, which
included different Image resolutions. After the completion ofrough match, fine-match is essential. The performance of region
covariance descriptor is superior to other methods, and thepyramid matching algorithm performs extremely rapidly andaccurately, as it is shown, and the large rotations and illumination
changes are also absorbed by the covariance matrix.

10030-72, Session Post

Non-uniformity correction method of
IRFPA based on lookup table
Kun Cui, Xiaofeng Su, Shanghai Institute of TechnicalPhysics of the Chinese Academy of Sciences (China)
The non-uniformity correction method of the infrared focal
plane array based on the blackbody calibration is widely used inengineering applications. In this kind of method, the correction
parameters obtained from the variation of the radiation energy
will be unavailable, when the integration time changes, andvice versa. To solve this problem, this paper presents a method
for non-uniformity correction of IRFPA based on lookup table.
In this method, the three-dimensional pixel response datawith the variation of the radiation energy and the integration
time is stored in a lookup table. Taking into account that the
pixel response output contains the instrument backgroundradiation, and the instrument background is greatly affected by
the environment, so the response data needs to subtract the
instrument background, which is also required in the course ofcorrection. During correction, the radiation energy interval isqueried depending on the real response value of pixel, according
to the current integration time. The radiation energy value is thenestimated by nonlinear interpolation algorithm. The normalized
function is used to obtain the corrected gray value corresponding
to the estimated radiation energy. In the case of that the current
integration time is not stored, the relation curve between the
response output and the radiation energy in this integration timeshould be estimated by using the nonlinear interpolation firstly.
When the pixel response rate is stable, the correction effect ofthe method this paper presents is better than the traditional
multi-point non-uniformity method. In addition, it’s very suitable
for the application that pixel with large response rate nonlinearity
and integration time changing frequently.

10030-73, Session Post

A novel visible and infrared image fusion
algorithm based on detail enhancement
Bo Wang, Huazhong Institute of Electro-Optics (China)
In order to improve the characteristic information of the fused
images, we propose a novel infrared and visible image fusion
algorithm based on image detail enhancement in this paper, thebilateral filter and dynamic range partitioning (BF & DRP) areused to improve the original infrared image, and the multi-scale
retinex transform (MRT) also is used to deal with image fusion.
Firstly a method of bilateral filter and dynamic range partitioning(BF & DRP) was used to improve the details of the low SNR
and low contrast original infrared image, by which the edgesof targets were strengthened, the noises were suppressed, andthe constrast of infrared image was enhanced. Secondly, andfinally, the multi-scale retinex transform was used to improve thefusion of visible and infrared image, by combining the multi-scaletransform and regional fusionwhere the adaptive low frequency
and high frequency coefficient were considered, which effectively
suppressed the noises and enhanced the details..

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253

Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
Experimental results proved the effectiveness of the proposed
image fusion method. The salient color and texture feature ofvisible image was well preserved, the important details of infraredand visible image were highlighted. The results show that thisalgorithm is better than traditional image fusion method, suchas wavelet transform, non-sampled contourlet transform, inmean square error, standard deviation, entropy, cross entropy
and cross-correlation etc.. the algorithm of this paper is able topreserve the details of image, increase the amount of importancecharacteristic information, is advantageous to the visualperformance and distinguishability of fused image for humanobservation.

10030-74, Session Post

Terahertz characteristics of graphene
deposits on different substrates
Chen Gong, Jian Zuo, Cunlin Zhang, Capital Normal Univ.
(China)Graphene is a promising candidate material for ultra-broadband
photodetectors, as it interacts with light strongly from microwave
to ultraviolet. We have characterized terahertz (THz), IR and UVvisible response from monolayer graphene samples depositedon Cyclo Olefin Polymers (COP) and Polymethylmethacrylate(PMMA) substrates. The transmittance, sheet conductivity,
and attenuation of graphene samples were obtained fromtransmission terahertz time-domain spectroscopy (THz-TDS).
The carrier density of graphene is calculated to analyze themechanism underlying this photoconductive response. The
mechanisms that contribute to the optical response of graphene
were quite diverse among the different substrate media used.
The results are promising for the development of modulators andswitchable photoelectric devices.

10030-75, Session Post

Reducing the uncertainty in terahertz
time-domain reflection spectroscopy

The terahertz time-domain reflection spectroscopy (THz-TDRS)
has recently emerged as a powerful tool in investigation ofmaterials. The parameter extraction process based on THzTDRS is nearly perfect. The traditional method to extract
optical parameters of materials based on THz-TDRS is thatusing the total reflection mirror as reference. However, themeasurements for signals still contain errors, which affect thequality of the extracted optical parameters. Several sources ofrandom and systematic errors exist throughout the measurement
process. These sources are, for instance, signal noise, sample
misalignment, thickness measurement variation, phase error,
etc. Thus, reducing uncertainty is critical in the optimization of
measurement accuracy. In this paper, we used the self-referenced
method proposed in our previous study to extract the opticalparameters. As a result, the intrinsic phase error existing in the
traditional method was eliminated. In addition, the variance of thetime-domain signal is lower. We also reduced the error originatedfrom sample thickness by using genetic algorithm through design
the thickness as an optimized parameter. We draw a conclusionthat the self-referenced method can obtain more accurate opticalparameters. Through analyzing the combined uncertainties we
can understand the systemic and random influences on opticalparameters.

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Standoff gas identification and application
with FTIR imaging spectrometer
Chensheng Wang, Huazhong Institute of Electro-Optics(China); Song Yue, Jiuzhiyang Infrared System Co., Ltd.
(China); Zhijie Zhang, Hui Yu, Pu Hong, Huazhong Instituteof Electro-Optics (China); Wei Sun, Jiuzhiyang Infrared
System Co., Ltd. (China)
Fourier transform infrared imaging spectrometer has theadvantages of high spectral resolution, good sensitivity andstaring mode, and it is considered as an ideal solution forlong distance and mobile gas identification. This feature hassignificant meaning in the fields like industrial plume emission
monitoring and public security monitoring. In this paper, a LWIRFTIR imaging spectrometer is applied to realize the field gas
identification experiment. First, the structure and design of thisspectrometer is indicated and discussed. Based on the specificinterferometer design and high performance infrared imaging
module, this instrument can provide stable performance infield application. Then, the basic principle of FTIR imaging dataprocess is described, which includes the reconstruction methodof data-cube and the spectral identification and unmixing in gas
detection. Based on the algorithms research and operation mode
analysis, the related gas identification software is developed toachieve a high-efficiency detection work. To verify this design,both lab and field experiments are realized. At lab, SF6 and NH3
gas are applied to verify the spectral identification algorithm
and test the spectral resolution of the spectrometer, and theresults show that this spectrometer can meet the requirementsof field gas identification application. After that, the field trial
is completed with the permission from the local environmental
protection agency. The instrument is delivered via van to theindustrial area located in Wuhan City, and applied to analyze
the components in the plume emission gas. The field test results
show that this FTIR imaging spectrometer can be easily operated
to identify the gas elements in real time, and give the reasonable
analysis results.

10030-77, Session Post

Xie Yijun, Ping Sun, Beijing Normal Univ. (China); Wenai
Wang, Capital Normal Univ. (China)

254

10030-76, Session Post

Spectrum modulation of terahertz
radiation from air plasma via femtosecond
laser pulses control
Ying Zhang, Wenfeng Sun, Yan Zhang, Capital Normal
Univ. (China)
Terahertz (THz) generation from air plasma can greatly reduce
the energy-loss of THz waves in air than the ones from opticalrectification crystal and photoconductive antenna, owing to
the lower absorption of water suffering in the propagation of
femtosecond laser. This superior makes it potentially useful forthe detection of remote targets. More efforts have been put
on increasing the amplitude of THz waves generated from air
plasma, yet few focuses have been on the spectrum of theseTHz waves. Therefore, the detection efficiency will be greatly
improved if the desirable THz spectrum can be obtained fromair plasma. In this paper, we propose a method to modulate
the spectrum of THz waves by controlling the wavefront of
the femtosecond laser pulses. The wavefront control has been
performed by loading phase maps on a Liquid Crystal Spatial
Light Modulator. The two serially-formed femtosecond filamentswith different length and diameter radiate THz waves under themechanism of Cherenkov radiation respectively. The spectrumsof THz waves have been modulated by varying the spatial
separation and electron density of the two filaments. With thismethod, the central frequency and the spectral bandwidth of thewww.spie.org/pa·

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
generated THz waves can be modulated as well. The modulated
spectrums that measured in the experiment are simulated
theoretically and discussed. The result indicates that this methodof dynamic modulation for THz spectrum will widely extend theapplication of THz remote sensing.

10030-78, Session Post

Vibrational spectral investigation ofanhydrous glucose in the terahertz range
Wenai Wang, Capital Normal Univ. (China); Ping Sun,
Beijing Normal Univ. (China); Wei Liu, Capital Normal Univ.
(China); Yijun Xie, Beijing Normal Univ. (China)
As a powerful tool for the research of molecular structure,
infrared absorption spectrum has been extensively studied
in the field of biomedical photonics. The infrared absorption
spectrum of anhydrous glucose has been measured by Fouriertransform infrared spectrometer (FTIR). The experimental
results provide an important reference for diabetes research anddiagnosis. The origins of the absorption features are generally
attributed to intermolecular vibrations and intramolecular
torsions. To investigate the physical specific structure and themolecular interaction in far-infrared band, the sample structure
properties were analyzed meticulously by solid-state density
functional theory (DFT) calculations. CASTEP quantum chemical
calculation software package was utilized to simulate the infrared
spectroscopy. of glucose crystal structure based on periodic
boundary condition and plane wave pseudopotential method.
In order to obtain glucose infrared absorption spectrum, linear
response approach and norm conserving pseudopotentials are
essential. Besides, the performance of the generalized gradientapproximation (GGA) functional has been commendably
examined. The results show that the standard Perdew-BurkeErnzerhof (PBE) approach along with its line Broyden-FletcherGoldfarb-Shanno (L-BFGS) algorithm tends to be superior.
The agreement between theory and experiment indicates thatthe crystal simulation calculation based on solid-state density
functional theory can identify substance absorption peaks andvibration attribution accurately in THz region.

10030-79, Session Post

The design of circuit for THz time
domain spectroscopy system based on
asynchronous optical sampling
Hailin Cui, Mile Zhang, Yihan Li, Jingsuo He, Capital
Normal Univ. (China)
Terahertz time domain spectroscopy (THz-TDS), as a new methodof spectrum analysis, will play a more and more important rolein basic scientific research in the future. However, the traditional
THz-TDS system takes a few to more than ten minutes to obtain a
THz pulse. Because of the way to scan a terahertz pulse is by themechanical step of mechanical delay platform, which can sample
only one point of a terahertz pulse every step. Therefore, there isa limitation of the THz-TDS system based on the mechanical step
delay device is that the system cannot be detected quickly. The
optical asynchronous sampling technique is the way to realize thefast detection of terahertz pulse. Not only studying the physicalprocess, the technology can also achieve high time resolution andhigh frequency resolution.
To solve the problem above, a circuit for THz-TDS Based on
Asynchronous Optical Sampling, which is the most importantof the THz-TDS system, is designed in this thesis. This thesis
focuses on the researching, designing and experiment of thiscircuit. Firstly, the circuit is designed overall. Then the selection

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Follow us on:of the key device and the designing of the circuit principle isdone by myself. Secondly, the test of the circuit to phase locked
the master and slave fiber femtosecond lasers has been done.
As a result, the two lasers can phase locked on two repetition
frequencies with a small frequency difference calculated by thecircuit.

10030-80, Session Post

Research on trace gas measurement by
ICOS with WMS
Zhenglong Ni, Jie Shao, Haibo Zhou, Kunyang Wang,
Zhejiang Normal Univ. (China)
Integrated cavity output spectroscopy (ICOS) is a very sensitive
method of trace gas measurement. It is widely known as
its extremely long optical path and characteristics of directabsorption. Wavelength Modulation Spectroscopy (WMS) is
another sensitive measurement method. It adds modulation on
the direct absorption so that achieves the noise suppression. We
combine the ICOS technique and WMS technique to research
the trace gas measurement using a narrow band tunable diodelaser. First?we set up a normal ICOS system. It can measure some
low line strength position. Then we modulate the laser with highfrequency sinusoidal signal and demodulation the output signal
from ICOS system into 2f signal by a lock-in amplifier. By thismethod we get several absorption peaks of carbon dioxide inatmosphere. To combine ICOS and WMS the sensitivity of trace
gas measurement has a significantly increase.

10030-81, Session Post

Investigation on optical properties of BSA
protein on single-layer graphene using
terahertz spectroscopy technology
Yiwen Sun, Shengxin Yang, Shenzhen Univ. (China)
Graphene has been wildly interested in developing novel devices
for electronics, photonics and optoelectronics recent years.
Single-layer graphene is a gapless two-dimensional material withunusual properties such as high electric and thermal conductivity
etc.. Also terahertz (THz) spectroscopy is sensitive to probe
several aspects of biological systems. In the terahertz frequency
region, electrically controllable Drude-like intraband absorption
makes graphene a promising platform for building active,
graphene-based optoelectronic devices such as THz biosensor.
Recently we demonstrate a highly sensitive terahertz timedomain spectroscopy method to monitor optical properties ofsilicon-based single-layer graphene and BSA protein on graphenein the frequency range of 0.1-3 THz. BSA protein thin films withdifferent thicknesses were spin coated on single-layer grapheneby controlling the spin coating speed. 808 and 1064 nm IR lasers
with different output power were used as the pump light tostimulate the sandwich-like sample (protein-graphene-silicon
substrate) respectively. The dispersion of substrates complex
refractive indices were extracted by comparing the signal
spectrum with the reference spectrum using the transmission
method. The graphene monolayer complex conductivity was
also calculated. The terahertz optical properties of protein ongraphene was strongly affected by the power of the pumplight. As expected, the conductivity increased with the powerincreasing. Additionally, the absorption peaks obviously appeared
at 1.7 THz for BSA protein on graphene monolayer by stimulating
808 and 1064 nm pump light but with the opposite phase, while
there was none absorption appearance for sandwich-like sample.

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255

Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-82, Session Post

10030-84, Session Post

Terahertz wavelength encoding
compressive imaging

Simulation study of microstrip line on THz
on-chip system

Qiong Zhang, Xinke Wang, Yan Zhang, Capital Normal
Univ. (China)

Cong Zhang, Bo Su, Ning Fan, Cunlin Zhang, Capital
Normal Univ. (China)

Terahertz (THz) compressive imaging can obtain two dimensional
image with a single or line detector, which can overcome thebottleneck problem of lacking of THz two dimensional detector.
In this presentation, a method is proposed to obtain two
dimensional image using a line detector.

At present, terahertz time-domain spectroscopy (THz-TDS)
system has important applications in many fields such as
semiconductors, pharmaceuticals, biological molecule and soon. Though the present THz-TDS systems using THz waves
propagating in free space work quite well, it also has many
limitations like large sample, low spectral resolution, large systemsize and strong water absorption. So this system is desired
to integrate it in a solid state chip to make the system morecompact and functional. In this paper, we put forward a terahertz
on-chip system which integrates terahertz generating device,detection device and waveguide transmission device. Waveguides
suitable for such high frequency electromagnetic waves in solidstate chips are coplanar waveguide (CPW) and micro-strip-line(MSL) familiar in microwave devices. The CPW is a structurein which all the conducting media are coplanar. The dielectric
beneath the conductors need be sufficiently thick to prevent
field leakage. The MSL consist of a strip conductor and a groundplane separated by a dielectric medium. The material of dielectric
substrates is benzocyclobutene (BCB) in our experiment. In the
on-chip system, the evanescent terahertz-bandwidth electricfield extending above the MSL interacts with overlaid dielectric
samples, thus the characteristics of the samples can be probed.
The HFSS software was used to simulate and analyze thetransmission characteristics of the CPW and MSL based on the
on-chip system researched by University of Leeds (America)and Hiroshima University (Japan). The simulation results showthat the scattering parameters of the two waveguides are similar
to the known literatures. Therefore, our simulation work canaccelerate the fabrication progress of the on-chip THz system.

A plano-convex cylindrical lens is employed to preform Fouriertransform and to encode the one dimensional information of
object into wavelengths. After recording both amplitude andphase information at each pixel of the line detector, the twodimensional image of the object can be reconstructed. Numericalsimulation demonstrates the validity of the proposed method.

10030-83, Session Post

Terahertz microfluidic chips for detectionof amino acids in aqueous solutions
Bo Su, Cong Zhang, Ning Fan, Cunlin Zhang, Capital
Normal Univ. (China)
At present, the detection methods widely used in biochemistry
are mostly labeled. Although they are precise, labeled matters
may pollute the samples. In order to overcome the shortcoming,
many researchers study the optical properties of biochemistry
samples in the range of terahertz (THz). Consequently,
the characteristic vibration modes of many biologicalmacromolecules, such as DNA or protein, are just located in therange of THz, so THz has the potential to detect biochemistry
samples.
Water plays very important roles in the functions of biologicalmolecules and the structure of proteins. Hydration, namely theinteraction between water and other molecules, involves many
biological phenomena. As a result, studying the characteristics ofaqueous solutions is closer to the demand.

10030-85, Session Post

Microfluidic technology is able to control the fluidic thickness
accurately in less than 100 micrometers. So the combinationof terahertz and microfluidic technology becomes one of
the most interesting directions towards biological detection.
We designed microfluidic chips for terahertz spectroscopyof biological samples in aqueous solutions. The microfluidic
chips were fabricated using the material of Zeonor 480, which
is both mechanically robust and optically transparent. Using
the terahertz time-domain spectroscopy (THz-TDS) system,
we experimentally measured the transmittance of the chips
and the THz absorption spectra of threonine and arginine withdifferent concentrations, respectively. The experimental results
demonstrated the feasibility of performing high sensitivity THz
spectroscopy of amino acids in aqueous solutions. Therefore,
the microfluidic chips are able to realize real-time and label-freemeasurement for biochemistry samples in THz-TDS system.

Huijuan Sun, Beijing Union Univ. (China); Qingli Zhou,
Capital Normal Univ. (China)

256

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The optical constants of two liquid
crystals in terahertz band

As the breakthrough of terahertz emitter and detection
technology, the unique and superior feature of terahertz waves
has been discovered and shows wide and promising applications
in communication, materials science, biological and medical
imaging, nondestructive testing, etc. It is impossible to theextensive application of terahertz technology without practical
function devices which can meet the special requirements indifferent application fields. Liquid crystals (LCs) have been thesubject of active research for more than a century. The mostprominent LC based device is the flat panel display, which enjoys
an ongoing commercial success and has revolutionized theelectronics industry. Apart from this mainstream application,
the unique properties of LCs also led to the development ofmany other optical components such as light valves, tunablefilters and tunable lenses. The optical properties of LCs havebeen investigated in detail covering the range from UV to
microwave frequencies. For the application of LCs in the THz
frequency range, knowledge of the dielectric anisotropy andelectro-optic properties of LCs in this frequency range is mostimportant. However, knowledge of the dielectric of LCs in theTHz range is still incomplete. THz time-domain spectroscopy(THz-TDS) has recently emerged as a powerful spectroscopic
technique to measure optical properties of materials in theTHz frequency range. THz spectroscopy contains rich physical,
chemical, and structural information of the materials, and one
unique attribute of THz is their ability to sensitively measurewww.spie.org/pa·

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
the induced molecular dipole moments of many liquid crystals.
In this paper, we prepared the testing cell by sandwichingcommercially available TEB300, 9023 LCs between two fusedsilica windows. The thickness of the two fused-silica windows is
0.701mm and 0.702mm. The measurements were made at room
temperature(25?). For each kind of liquid crystals, we scanned
three times for getting average value to decrease the error. The
transmission spectra of the liquid crystals such as TEB300, 9023
LCs were measured by THz time-domain spectroscopy techniqueand free-space electro-optic sampling method. The absorption
coefficient and refractive index of liquid crystals in the THz range
are calculated. Furthermore, the optical constants are compared
and analyzed, expecting to fill the spectrum gap of liquid crystals
in the THz range and provide the experimental and theoreticalfoundation for the application of liquid crystals.

10030-86, Session Post

Nitrocellulose membrane sample holder
for terahertz time domain spectroscopy
Xiaojing Zhao, Cuicui Wang, Jian Zuo, Cunlin Zhang,
Capital Normal Univ. (China)
Terahertz (THz) technology has promising applications for thedetection and identification of materials because it has a great
advantage in measuring material fingerprint spectrum. Terahertz
time-domain spectroscopy (THz-TDS) is a key technique that is
applied to spectroscopic measurement of materials. However,
it is difficult to press a pellet with small mass of sample and abulking medium such as polyethylene (PE) powder usually need
to be added. Characteristic absorption peaks of the solution inliquid cell is hard to be observed due to the interaction between
materials and water molecules. Therefore, one method using
the hydrophilic nitrocellulose (NC) membrane as a sample
holder was applied to detect samples in an aqueous medium
by THz-TDS. In this study, the ?-lactose samples were mixed
with 20 ?l of deionized water and then applied directly onto
the double-layered NC membrane sample holder. This mixture
is located on the gap of two piece of NC membranes. Firstly
the NC membranes with different pore sizes were tested in theexperiment. And then the ?-lactose solutions with different
concentrations were measured on the NC with different poresizes. Consequently, the small mass of samples can be detected
and the characteristic absorption peaks become stronger
with the increase of NC pore size. Moreover, compared to the
traditional pellet-making and liquid cell detection, this membrane
method is more convenient and easy to operate.

10030-87, Session Post

Design and research for biosensing THz
microfluidic chips
Ning Fan, Bo Su, Cong Zhang, Cunlin Zhang, Capital
Normal Univ. (China)
Many Biomolecules vibration frequencies are in THz (0.1THz10THz) frequency range, so terahertz technology is an essential
tool for detecting biological molecules. However, due toterahertz strongly absorbed by water, it is difficult to detect
these molecules for biological and chemical liquid samples.
Therefore, we present a novel detection method by combining
terahertz technology with microfluidic technology. The strong
absorption of water is effectively overcome by controlling thelength that terahertz passes through liquid samples. What’smore, a higher signal to noise ratio is obtained through using
less samples. In this paper, we designed a THz microfluidic chipthat is easy to be fabricated by using the materials of zeonex
and polydimethylsiloxane (PDMS). Using terahertz time-domain-

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spectroscopy (THz-TDS) system, we find that the chip has ahigh transmittance above 85% in the range from 0.1 THz to 2.4
THz. Then the THz spectra of deionized water and different
kinds of electrolyte solutions with different concentrations in the
microfluidic chip were measured, respectively. In our research, it
is found that different kinds of electrolyte solutions have different
absorption coefficients for THz. In addition, the absorption
indexes of some electrolyte solutions markedly increased andothers significantly reduced comparing with deionized water.
In addition, the THz absorption spectrum changes with theconcentration of the same kind of electrolyte.

10030-88, Session Post

Investigation of transient temperature’s
influence on damage of high-speed sliding
electrical contact rail surface
Yuyan Zhang, Shasha Sun, Yanshan Univ. (China)
In the high speed sliding electrical contact with large current,
the temperature of contact area rises quickly under the coupling
action of the friction heating, the Joule heating and electric arc
heating. The rising temperature seriously affects the conductivityof the components and the yield strength of materials, as wellaffects the contact state and lead to damage, so as to shorten
the service life of the contact elements. Therefore, there isvital significance to measure the temperature accurately andinvestigate the temperature effect on damage of rail surface.
Aiming at the problem of components damage in high speed
sliding electrical contact, the transient heat effect on the contact
surface was explored and its influence and regularity on thesliding components damage was obtained. A kind of real-timetemperature measurement method on rail surface of high speed
sliding electrical contact is proposed. Under 2.5 kA current
load condition?based on the principle of infrared radiation
non-contact temperature sensor was used to measure the rail
temperature. The dynamic distribution of temperature field was
obtained through the simulation analysis, further, the connection
between temperature changes and the rail surface damage
morphology, the damage volume was analyzed and established.
Finally, the method to reduce rail damage and improve the life ofcomponents by changing the temperature field was discussed.

10030-89, Session Post

Space-time adaptive: ratio, resolution, andmultiple configuration
Hua Liu, Science and Technology on Electro-Optic Control
Lab. (China)
The principle approach, modeling, and error analysis areanalyzed, and the system configuration based on SLM isadvanced in algorithm analysis. For to improve the resolutionof the imaging system, and achieve the theoretical limit, we
introduced that the core methodology, which is that in the deep
understanding and research of the photoelectric information
control, the basic theory of the spatial light modulator and thealgorithm based on space-time adaptive system is discussed
deeply which used to the core of the photoelectric system
configuration by which key components applied to solve thecontrol function. This paper discusses the hardware system.
Usually, an SLM modulates the intensity of the light beam.
However, it is also possible to produce devices that modulate
the phase of the beam or both the intensity and the phasesimultaneously. Adaptive configuration, for a complicate sensor isaccomplished by an implementation of structured programming,based on global optimization algorithm , which explores theavailable configuration space formed by powers of individualcomponents and inter-component separations. Besides, the#PhotonicsAsia

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
discuss includes the control on the SLM for spatial information of
the amplitude, phase, frequency, polarization, and the intensityof energy research. A typical model is used to illustrate thefeasibility, and the criteria is developed.The technology principleof super resolution restructure from the point of view on theory
and engineering. Three kinds of restructure technologies, that
prototype, micro scanning and sub pixel are described, andhow to decrease their shortcomings are discussed in detail.
Furthermore, to improve the band width by reconstruction
without the spectral alias in super resolution technologies, a newcoding technology combining a optical encoding and the sub
pixel is proposed. With the global method, simulation results
show that the system can meet the application requirements in
MTF, REA, RMS and other related criteria.Results show that they
are effective solutions.

10030-90, Session Post

Detection of NaCl solutions using
terahertz time-domain spectroscopy
Cuicui Wang, Xiaojing Zhao, Jian Zuo, Cunlin Zhang,
Capital Normal Univ. (China)
Terahertz spectrum is corresponding with vibration and rotationof liquid molecules. It is suitable to identify and research theliquid molecular dynamics. As a powerful spectral detection
technology, terahertz time-domain spectroscopy (THz-TDS) is
widely used in solution detection. The absorption coefficient,refractive index and dielectric function of solutions can beextracted based on terahertz time-domain spectroscopy. NaCl
exists in most biological tissues, and it is very important forlife. In this paper, we detected NaCl solutions with different
concentrations at room temperature by THz-TDS technique in therange of 0.2-1.5 THz. The liquid cell with a thickness of 0.2mm is
made of quartz. A linear increase of the real and imaginary partof the dielectric function was observed when compared with purewater with increasing concentrations of NaCl solutions. We fitted
the terahertz dielectric function of the NaCl solutions by Debye
model, Where the dielectric relaxation time can be obtained.
By means of dielectric relaxation process, it was found that thecharacteristic time of molecular movement and the information
related to the liquid molecular structure and movement was
obtained.

10030-91, Session Post

Detection of text information hidden in an
envelope using terahertz imaging
Zhenwei Zhang, Cunlin Zhang, Capital Normal Univ.
(China)Multiply pages text information hidden in an envelope can beobserved clearly and by utilizing the frequency modulation
continuous wave terahertz imaging technology. The delay time
between the probe and reference signal was calculated andthen the positions of the object in depth were estimated. The
phase information and two-dimensional scanning were combined
together to obtain the three-dimensional tomographic imaging
data. Layer resolution is better than 1mm. The spatial resolution
is 1 mm. Layered images can clearly show the text at the different
page. By further improving the accuracy of the hardware andincreasing data denoising algorithm in order to improve the layer
resolution and spatial resolution, we can achieve a more clear andintuitive image. Meanwhile, the method can be further applied to
non-destructive testing of other sealed objects and skin burns.

258

SPIE Photonics Asia·

10030-92, Session Post

Design and simulation of a tunable
metamaterial absorber
Yanan Fu, Guozhong Zhao, Capital Normal Univ. (China);
yonghua li, capital normal university (China)
A photo-excited tunable and broadband metamaterial absorberin the terahertz region is proposed. The metamaterial absorberis composed of three layers like the sandwich, the top layer isacirclr metal-semiconductor circle split ring and the bottom
layer is a metallic ground plane, these two layers are separated
by a dielectric spacer, which we choose as the polyimide. The
conductivity of the silicon can be tuned actively with the incident
pump power. We use the full wave simulation and the equivalentcircuit model to analysis this absorber, and interpreted thephenomena showed when the conductivity of the silicon filledin the gap of ring is changed by the surface current and theelectric field. The proposed equivalent circuit model can savemore time to design this kind of absorber in need. The proposed
photo-excited tunable metamaterial absorber can also be used as
terahertz modulators and switches.

10030-93, Session Post

Electrically controlled terahertz wave
switch based on prism/liquid crystal
Meng Yao He, Jian-rong Hu, Jiu-sheng Li, China Jiliang
Univ. (China)
It is well known that there has a lateral displacement between
the centre of a practical reflected beam and the prediction ofgeometrical optics on the reflection interface. This phenomenon
is called as Goos-Hanchen (GH) shift. The GH shifts were studied
both theoretically and experimentally in the fields of microwave,
infrared wave, and visible light region. Meanwhile, some uniqueeffects have already been revealed in terahertz region. Basedon this, in this work, a novel terahertz wave switch scheme canbe developed utilizing prism/liquid crystal structure. A terahertz
wave detector is fixed at the prism external position of thereflected terahertz wave beam (i.e. the detector locates at theprediction position of geometrical optics). It can control the
position of the reflected terahertz wave beam (e.g. When the
fixed detector receives the terahertz wave signal, named “ON”,
i.e. compared to 1; or else, named “OFF”, i.e. compared to 0).
The terahertz wave ON–OFF mechanism of the novel switch isbased on a dynamic shift of the lateral GH shift of the reflectedterahertz wave beam. This proposal provides a convenient toolfor controlling the lateral shift of the reflected terahertz wave
beam by adjusting the external applied electric field withoutchange the configuration. The stationary phase theory (SPT)
method and the finite element method (FEM) are used to verify
and analyze the characteristics of the proposed switch. Numericalsimulation results show that the presented switch has a highextinction ratio, simplicity, small size, and a low cost. Because of
its excellent characteristics, the novel terahertz wave switch canbe used in future terahertz communication integrated circuits.
Moreover, it may also be easily extended to other terahertz
wave frequencies switching through changing the structure
parameters.

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-94, Session Post

10030-96, Session Post

Tunable terahertz power divider based ongraphene plasmonic waveguideResearch of biological liquid albumin
based on the terahertz time-domain
spectroscopy

Yang Li, Jian-rong Hu, Jiu-sheng Li, China Jiliang Univ.
(China)In this letter, a tunable terahertz power divider based ongraphene ribbon embedded in the PMMA substrate is analyzed.
The numerical simulations are carried out in the configuration
using the finite element method (FEM). In order to obtaina better extinction ratio, the optimized structure with fivegraphene ribbons is proposed. The power divider effects canbe dynamically controlled by varying the Fermi energy of thegraphene waveguides and the coupling length between thegraphene plasmonic waveguides. The tunable terahertz power
divider phenomenon has been observed in our five grapheneribbons system. The total size of the presented terahertz wave
beam splitter is of 5?m?4?m. With the help of the graphene
plasmonic waveguide, the dimensions of the power splitterare reduced dramatically when comparing with the traditional
waveguide power splitter. It is believed to be applicable for
future plasmonic circuit in terahertz ranges. This work may pave
the ways for the further development of ultracompact highperformance terahertz wave devices.

For no corresponding fingerprint characteristic spectrum
detecting complex ensemble biological samples in liquid, in thepaper, such urine of kidney disease patients as samples, using
terahertz time-domain spectroscopy emphatically explores
response characteristics of the urine albumin in the terahertz
region. Combined with stoichiometric method, we find a certain
kind of relationship between terahertz spectrum data and thecontent of urine albumin, which offsets the defects of otherspectroscopy in measuring liquid protein, and in accordance withhospital clinical data. This study established a semi-qualitative
method about using terahertz spectroscopy in detecting nonpurification of biological liquid sample, which provides a simple,
nondestructive, cheap and fast reference method in identifying
the early nephropathy for medical test.

10030-97, Session Post

Processing and fusion for human bodyterahertz dual-band passive image

10030-95, Session Post

Pepper seed variety identification
based on visible/near-infrared spectral
technology
Cuiling Li, Xiu Wang, Zhijun Meng, Pengfei Fan, Jichen Cai,
Beijing Academy of Agriculture and Forestry Sciences(China)Pepper is a kind of important fruit vegetable, with the expansionof pepper hybrid planting area, detection of pepper seed purity
is especially important. This research used visible/near infrared(VIS/NIR) spectral technology to detect the variety of single
pepper seed, and chose hybrid pepper seeds “Zhuo Jiao NO.3”,“Zhuo Jiao NO.4” and “Zhuo Jiao NO.5” as research sample. VIS/NIR spectral data of 80 “Zhuo Jiao NO.3”, 80 “Zhuo Jiao NO.4”
and 80 “Zhuo Jiao NO.5” pepper seeds were collected, andthe original spectral data was pretreated with standard normal
variable (SNV) transform, first derivative (FD), and SavitzkyGolay (SG) convolution smoothing methods. Principal component
analysis (PCA) method was adopted to reduce the dimension of
the spectral data and extract principal components, according to
the distribution of the first principal component (PC1) along withthe second principal component(PC2) in the two-dimensional
plane, similarly, the distribution of PC1 coupled with the thirdprincipal component(PC3), and the distribution of PC2 combinedwith PC3, distribution areas of three varieties of pepper seeds
were divided in each two-dimensional plane, and the discriminantaccuracy of PCA was tested through observing the distribution
area of samples’ principal components in validation set. This
study combined PCA and linear discriminant analysis (LDA) to
identify single pepper seed varieties, results showed that with the
FD preprocessing method, the discriminant accuracy of pepper
seed varieties was 98% for validation set, it concludes that using
VIS/NIR spectral technology is feasible for identification of single
pepper seed varieties.

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Shuai Yang, Capital Normal Univ. (China)

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Li Tian, Beijing Institute of Technology (China); Yanchun
Shen, Capital Normal Univ. (China); Weiqi Jin, Beijing
Institute of Technology (China); Guozhong Zhao,
Capital Normal Univ. (China); Yi Cai, Beijing Institute ofTechnology (China)
Compared with microwave, THz has higher resolution, andcompared with infrared, THz has better penetrability. Humanbody radiate THz also, its photon energy is low, it is harmlessto human body. So THz has great potential applications in the
body searching system. Dual-band images may contain different
information for the same scene, so THz dual-band imaging havebeen a significant research subject of THz technology. Base on
the dual-band THz passive imaging system which is composedof a 94GHz and a 250GHz linear-array detector, this paper
researched the de-noising algorithm and the fusion algorithm
for THz dual-band images. Firstly, the intensity of THz waves
radiated by human is small, and superadded the limitation of
detector and optical mechanical scanning imaging mode, THz
images have such problems: large noise, low SNR, low contrast,
low details. Secondly, the stability problem of the opticalmechanical scanning system makes the images less repetitive,
obvious stripes and low definition. Aiming at these situations,this paper used the BM3D de-noising algorithm to filter noise andcorrect the scanning problem. Furthermore, translation, rotationand scaling exist between the two images, after registered by
the intensity-base registration algorithm, and enhanced by theadaptive histogram equalization algorithm, the images are fusedby image fusion algorithm based on wavelet. This effectively
reduced the image noise, scan distortion and matching error,
improved the details, enhanced the contrast. It is helpful toimprove the detection efficiency of hidden objects too. Methodin this paper has a substantial effect for improving the dualband THz passive imaging system’s performance and promoting
technology practical.

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259

Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-98, Session Post

10030-100, Session Post

Detailed signal model of coherent windmeasurement lidar

Performance of passive terahertz imaging
systemYuechao Ma, Sining Li, Wei Lu, Harbin Institute ofTechnology (China)

Jia Wang, Guozhong Zhao, Capital Normal Univ. (China)

Lidar is short for light detection and ranging, which is a tool
to help measure some useful information of atmosphere. In
the recent years, more and more attention was paid to theresearch of wind measurement by lidar. Because the accurate
wind information can be used not only in weather report,
but also the safety guarantee of the airplanes. In this paper,a more detailed signal model of wind measurement lidar
is proposed. It includes the laser transmitting part which is
described the broadening of the spectral, the laser attenuationin the atmosphere, the backscattering signal and the detectedsignal. A Voigt profile is used to describe the broadening of thetransmitting laser spectral, which is the most common situationthat is the convolution of different broadening line shapes. The
laser attenuation includes scattering and absorption. We use aRayleigh scattering model and partially-Correlated quadraticSpeed-Dependent Hard-Collision (pCqSDHC) model to describe
the molecule scattering and absorption. When calculate theparticles scattering and absorption, the Gaussian particles modelis used to describe the shape of particles. Because of the Doppler
Effect occurred between the laser and atmosphere, the windspeed can be calculated by the backscattering signal. Then, a
two parameter Weibull distribution is proposed to describe thewind filed, so that we can use it to do the simulation. After all
the description, the signal model of coherent wind measurement
lidar is decided. And the simulation is also given by MATLAB.
This signal model can describe the system more accurate andmore detailed, so that the following work will be easier and more
efficient.

10030-99, Session Post

Primary study on scattering property forirregular suspended particles in water with
T-matrix theory
Yanan Liu, Chongqing Technology and Business Univ.
(China); Peng Feng, Chongqing Univ. (China)
In this paper, based on T-matrix theory we describe how
scattering spectrum by small non-spheroid suspended particles
can be computed and measured; spheroid, finite circular cylinderand generalized Chebyshev, three non-spheroid particles oflight scattering model is constructed. Results for non-sphericalsuspended particles scattering intensity will be presented.
Analyze the relationship among suspended particles of size
parameters, the relative refractive index, and the light scattering
intensity. In addition, the change of the suspended particles inwater of relative scattering intensity using different wavelength,
size parameter, and scattering angle has been calculated. Our
numerical results show that when the particles size and thewavelength of incident light changes, the scattered light intensity
is significantly changed with the different types of suspended
particles. These results provide a new approach to conduct
effective water quality testing data preprocessing by UV - visible
absorption spectroscopy.

260

SPIE Photonics Asia·

Terahertz (THz) radiation has the higher penetration to clothing,cardboard boxes, plastic packaging materials and other similar
dielectrics. Its lower photon energy compared with X-rays makethe detected material and the human being to be not destroyed.
THz application in field of security are developed by many
countries. In this research, we present a multiband of passive
terahertz imaging by the thermal radiation measurement. The
Noise Equivalent Temperature Difference?NETD? is obtained.
The result shows that NETD of the passive imaging system is
0.8K@17? and 24? at 94 GHz, and 1.5K@17? and 24? at 250GHz.
We found that the main source of noise is the noise fromdetection circuit. Finally, the improvement methods of detecting
sensitivity are analyzed and discussed.

10030-101, Session Post

Research on THz stepped-frequency ISAR
imaging
Meiyan Liang, Shanxi Univ. (China)
With the bandwidth of 12 GHz, a 0.2THz stepped-frequency
radar system is designed in the paper. Then, the principle of THz
inverse synthetic aperture radar (ISAR) imaging is introduced.
Based on the small rotate angle and the far field approximation,
the Range-Doppler algorithm is used in the simulation of ISAR
imaging. The simulation results show that THz stepped-frequency
radar can achieve high resolution ISAR images of aircraft, theresolution of ISAR images can reach centimeter-scale, which laida theoretical foundation for radar imaging in THz band.

10030-102, Session Post

FPGA-based hardware optimized
implementation of signal processing
system for LFM-pulsed radar
Noor Ul Azim, Wang Jun, Beijing Univ. of Aeronautics andAstronautics (China)
Signal processing is one of the main parts of any radar system.
Different signal processing algorithms are used to extract
information about different parameters like range, speed,
direction etc, of a target in the field d of radar communication.
This paper presents LFM (Linear Frequency Modulation) pulsed
radar signal processing algorithms which are used to improvetarget detection, range resolution and to estimate the speedof a target. Firstly, these algorithms are simulated in MATLAB
to verify their concept and theory. After the conceptual
verification in MATLAB, the simulation is converted into
implementation on hardware using Xilinx FPGA. Chosen FPGA
is Virtex-6 (XC6LVX75T). For hardware implementation pipeline
optimization is adopted and also other factors are considered
for resources optimization in implementation process. Focusing
algorithms in this work for improving target detection, range
resolution and speed estimation are hardware optimized fast
convolution processing based pulse compression and pulse
Doppler processing

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-23, Session 510030-25, Session 5

2D and 3D THz imaging: necessity of
automated data processing tools (Invited
Paper)

New progress of active and passive
terahertz imaging (Invited Paper)

Patrick Mounaix, Hugo Ballacey, Jean-Paul Guillet, Frederic
Darracq, Fréderic Fauquet, Jean Baptiste Perraud, Joyce
Bou Sleiman, Univ. Bordeaux 1 (France); Benoit Recur,
NOCTYLIO (France)
In the field of non-destructive testing, 3D Terahertz (THz)ability offers a modern solution to inspect opaque objects orthin multilayer. Time of flight considerations or tomographic
procedure, reconstruct a 3D volume of the acquired sample byintensive calculations of a huge quantity of data. This resulting
depth information is then extracted either from spectro terahertz
imaging or from several projections acquired around theobject at different viewing angles in the case of tomographic
acquisitions. This property has made THz tomography a very
powerful technique for non destructive control. In this paper,
we present a complete image processing sequence to perform
and render non-destructive inspection from 3D terahertz (THz)images. We implement advanced data and image processing,including 3D visualizations of hierarchical or selected information.
That software includes, for example, all the steps starting froma 3D tomographic reconstruction of a sample from radiographs
acquired with a monochromatic millimeter wave imaging system
to an automated segmentation, extracting the different volumesof interest (VOI) composing the sample. That leads to 3D
visualization and dimensional measurements. This inspection iscompleted by a skeletonisation and caliber analysis, providing
an accurate assessment of the structure, geometry and themorphology of the acquired object

10030-24, Session 5

Terahertz super-focusing and superresolution (Invited Paper)
Yiming Zhu, Univ. of Shanghai for Science and Technology(China)We report two methods to achieve the terahertz (THz) superfocusing and super-resolution imaging, respectively. The first
method is based on the spiral array plasmonic lens, whichis consist of the archimede helix and the circular antenna.
This method is characterized by high intensity focusing andpolarization sensitivity. Our results demonstrate that it cangenerate a focal spot with an FWHM of almost ?0.38? under rightcircular polarized light (CPL) illunimation. We also compare withthe plasmonic lens illuminated under linearly polarized light (LPL)
and right circularly polarized light (CPL). The results demonstratethat our designed plasmonic lens has a good focusing
performance as well as an advantage in focusing intensity. The
second method to obtain the THz super-resolution imaging is byusing the transformation optics (TO). As well known, TO is a new
way to manipulate transmission path of electromagnetic waves.
And, we propose another new kind of method to realize superresolution imaging in the far field by using shifting media basedon TO theory. Unlike hyperlenses and metalenses engineered byanisotropic materials, and superlenses based on left-hand media,
an alternating layered structure of homogeneous and isotropic
materials with positive permittivity and permeability (i.e. positive
index of refraction) can be used to design this shifting media dueto the effective medium theory. The results demonstrate that thisshifting media may open a new perspective for super-resolution
imaging.

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Guozhong Zhao, Capital Normal Univ. (China)
The progress of terahertz imaging at Capital Normal University
in Beijing is presented. Our works on Terahertz Imaging include
the active and passive imaging. For the active terahertz imaging,
the pulse and continue wave terahertz imaging are studied,respectively. The active terahertz pulse imaging is based on
the terahertz time-domain spectroscopy with the probebeam-expanded femtosecond pulse laser and an infrared CCD
detection. The active terahertz continuous wave imaging is basedon a CO2-laser-pumped terahertz coherent source and a NEC
terahertz camera. For the passive terahertz imaging, the low
frequency of terahertz radiometers are used to detect the beamscanned terahertz signal by the point-to-point method. The
related components and methods are developed and used for the
improvement of the imaging speed and the resolution of images.
The polarization terahertz imaging is studied based on the active
continuous wave imaging technology. The higher resolution ofterahertz imaging is achieved at 3.1 THz of operating frequency.
The polarization imaging provide more information on themeasured targets. However, the imaging distance of the highfrequency, such as 3.1 THz, of terahertz imaging is limited dueto the vapor absorption. The focal plane terahertz imaging
is developed to obtain more frequency domain of spectral
information. The focal plane imaging can be realized as a quasinear field imaging so that it can achieve at a higher resolution.
But the visual field of focal plane imaging is limited due to thesize of electro-optic crystal. The passive terahertz imaging isdeveloped for the longer imaging distance and the larger imaging
visual field. The sensitivity of terahertz radiometer is a key factor
for the contract and resolution of passive terahertz imaging.
In summary, the active and passive terahertz imaging areinvestigated at Capital Normal University. The advantage anddisadvantage of different terahertz imaging technology can beseen and compared. Of course, they depend on the different
requirements of application, too. Some further investigations ofterahertz imaging are necessary.

10030-26, Session 5

Application advances of terahertz digitalholography (Invited Paper)
Xinke Wang, Yan Zhang, Capital Normal Univ. (China)
With the maturation of terahertz (THz) technology, THzsensing and imaging systems have gradually demonstrated
their significant impact in the modern optics due to theproperties of THz radiations, such as low photon energy,
high transmission, broad spectral information. Herein, THz
imaging technology, which can coherently reconstruct thetwo-dimensional information of a sample, is one of the mostimportant development directions. In this presentation, we
will review some attempts we carried out in the THz digitalholography system. A THz holographic imaging system is built
and its main performances are elucidated, including higher
spatial resolution, better signal-to-noise ratio and polarizationselected measurement. Utilizing this system, various THz imaging
applications are performed, including demonstration of THz
planar elements, exploitation of optical tunable THz devices,
observation of the THz longitudinal field in a free space and theTHz surface wave on a metallic sub-wavelength structure. These
works push forward the development of THz integration systemand broaden application fields of THz imaging#PhotonicsAsia

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-27, Session 610030-29, Session 6

Tunable and reconfigurable THz devices(Invited Paper)

Active terahertz device based on
optically-controlled organometal halide
perovskite (Invited Paper)

Jinghua Teng, Institute of Materials Research andEngineering (IMRE) (Singapore)

Bo Zhang, Capital Normal Univ. (China)

Terahertz wave is the fingerprint spectral range for many
molecules and has far-reaching applications from molecular
spectroscopy to security screening and bio-imaging. The wide
adoption of THz technology requires the development ofhigh performance and compact THz sources, detectors andvarious components. Tunable devices will add functionality andflexibility to the THz system design and application, besides
other advantages. The unique properties of surface plasmonsand metamaterials such as the strong field localization andenhancement and the flexible control of the permittivity
and permeability bring new ways and opportunities to THztechnology development. In this talk, I will introduce severalof our work on tunable and reconfigurable THz devices
using plasmonics and metamaterials. They include the highefficiency continuous wave THz emitter using a nano-electrode
incorporated photomixer, broadband response with concurrent
filed localization and optical tuning of THz transmission using
InSb plasmonic response in the THz range, the graphene
based multi-layer structure for compact optical switching,modulation and substantial Faraday rotation, and reconfigurable
metamaterials using MEMs structure and phase change materials.

Integrated terahertz optoelectronics(Invited Paper)
Qi Jie Wang, Nanyang Technological Univ. (Singapore)
Terahertz (THz) quantum cascade laser (QCL) is a semiconductor
based heterostructure laser based on intersubband transitions.
Although THz QCLs have been developed with relatively highperformance, there is always a need to further improve the device
performance, for example, achieving high beam collimated,polarization arbitrarily controlled, and high speed modulation. It
is also desired that those performance could be achieved throughan integrated approach for miniaturalization, easy alignment andreducing cost.
In this presentation, we will demonstrate high collimatedTHz quantum cascade lasers through plasmonic collimation
designs with a record beam divergence, electrically tunable
THz polarizations by designing integrated THz metasurfaces
on a hybrid dielectric-plasmonic waveguides, and broadband
graphene-based integrated THz modulators with a fast
modulating speed.

SPIE Photonics Asia

10030-30, Session 6

Development of high-performance
terahertz metasurface flat lens (Invited
Paper)
C.-C. Chang, The Ctr. for Integrated Nanotechnologies(United States); D. Headland, Withawat
Withayachumnankul, Derek Abbott, The Univ. of Adelaide(Australia); Hou-Tong Chen, The Ctr. for Integrated
Nanotechnologies (United States)

10030-28, Session 6262

An active all-optical high-efficiency broadband terahertz device
based on an organometal halide perovskite (CH3NH3PbI3,
MAPbI3)/inorganic (Si) structure is investigated. Spectrally
broadband modulation of the THz transmission is obtained in thefrequency range from 0.2 to 2.6 THz, and a modulation depthof nearly 100% can be achieved with a low-level photoexcitation
power (~0.4 W/cm2). Both THz transmission and reflection were
suppressed in the MAPbI3/Si structure by an external continuouswave (CW) laser. Enhancement of the charge carrier density at
the MAPbI3/Si interface is crucial for photo-induced absorption.
The results show that the proposed high-efficiency broadband
optically-controlled terahertz device based on the MAPbI3/Si
structure has been realized.

·

Conventional optical lenses focus electromagnetic waves by
imparting position-dependent phase delay through shaping theirgeometry. This poses difficulties in eliminating the geometricaberrations in high numerical aperture lenses, in addition to thefabrication challenges when operating at short wavelengths (e.g.
visible light), and bulky devices operating at long wavelengths(e.g. microwaves). In contrast, metasurfaces realize full control ofphase through tailoring the subwavelength resonant structures,
allowing for the demonstration ultrathin flat lens without
suffering from geometric aberrations, although the efficiency is
still rather low using single-layer metasurfaces. Here we report
the demonstration of high-performance flat lens in the terahertz
frequency range using few-layer metasurfaces. The three-layer
metasurface structure is capable of rotating the incident linear
polarization by 90° with a very high efficiency over a bandwidthof two octaves. More importantly, the phase of the output light
can be tuned over the entire 2? range with subwavelength
resolution through simply tailoring the structure geometry of thebasic building blocks. Based on this success, we design, fabricate,and characterize a metasurface lens operating at 0.4 THz. Witha lens diameter and focal length both 5 cm, we realize a highnumerical aperture of 0.44 and diffraction-limited focal diameterof 2 mm. Terahertz time-domain spectroscopy measurements
show that the metasurface lens is capable of achieving the same
signal intensity as compared to a TPX lens of the same diameterand focal length.

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-31, Session 6

Electromagnetically-induced
transparency-enabled asymmetric surface
plasmon excitation (Invited Paper)
Xueqian Zhang, Quan Xu, Quan Li, Yuehong Xu, Jianqiang
Gu, Zhen Tian, Chunmei Ouyang, Jiaguang Han, Ctr. for
Terahertz Waves of Tianjin Univ. (China); Weili Zhang, Ctr.
for Terahertz Waves of Tianjin Univ. (China) and Oklahoma
State Univ. (United States)
Surface plasmons (SPs) has promised a variety of cuttingedge applications, such as deep-subwavelength lasing, highresolution imaging, and ultrasensitive biomedical sensing.
Freely control over SPs is highly desired in developing next
generation of integrated photonic devices. Recently, excitationof asymmetric SPs using structured metallic surface has drawn
huge interest, which is quite potential in plasmonic circuitries
and communications. Among these studies, such excitation was
realized either by engineering the phase gradient at the metaldielectric interface so as to make the momentum matchingcondition satisfied in a selective SP excitation direction, or bycontrolling the SP interference of two or more separated couplers
with different SP excitation phases. However, the coupling effects
among the excitation units were usually ignored, which actually
could also be very useful in controlling SP excitation. In this work,
we demonstrated an exotic approach in exciting asymmetric SPs
in the terahertz regime by introducing the electromagneticallyinduced-transparency (EIT) coupling mechanism. In the freespace regime, EIT metamaterials have been widely investigatedto manipulate the electromagnetic waves by designing thecoupling between a bright and a dark resonator. Here, in thenear-field regime, we also applied such coupled bright and darkresonators as basic excitation units. By changing their relative
position, the coupling strength and thus the asymmetric levelof the excited SP pattern can be freely adjusted. Furthermore,
we also applied such controlling strategy into SP focusing.
The experimental results were characterized by our recently
developed near-field scanning terahertz microscope (NSTM)
system, which agree well with the theoretical predictions.

10030-32, Session 7

Infrared spectroscopy with visible light(Invited Paper)
Leonid Krivitsky, Dmitry Kalashnikov, Anna Paterova, Data
Storage Institute (Singapore); Sergei Kulik, Departmentof Physics, M.V. Lomonosov Moscow State University(Russian Federation)
The concept of nonlinear interference was introduced by Mandel
et al. in 1999. It is based on the interference of parametric down
conversion (PDC) beams from two non-linear crystals. Theinterference pattern depends on the total phase acquired bythree interacting modes: the pump, the signal, and the idler in the
gap between the two crystals. In case, when PDC is operated in
the frequency non-degenerate regime, the interference pattern of
the signal mode in the visible wavelength depends on the phaseof the idler photon in the infrared wavelength. In 2001 this idea
was used to measure dispersion of paraffin oil, and in 2014 it wasused for imaging phase objects.
Here we use the nonlinear interferometer for measurements ofrefractive indices and absorption coefficients of materials in
the Infrared range without the need for IR optical elements andsensors. We built a nonlinear Mach-Zender interferometer, where
mirrors are substituted by two nonlinear crystals, where the PDC
occurs. PDC is operated in the frequency non-degenerate regime,
and the interference pattern of the signal photon (in the visible

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range) depends on the phase of the idler photon (in the infrared range). The intensity distribution of signal photons shows
distinctive fringes. When the sample with resonance absorptionin IR-range is placed between the crystals, the fringes shift andtheir visibility is reduced. From modifications of the interference
pattern for the signal photon both, the refractive index and theabsorption coefficient at IR-wavelength can be easily calculated.

10030-33, Session 7

Analysis on blue and green pigmentsfrom the Thangka of Dhritarashtra (Invited
Paper)Rui Zhang, Xiaoji Fang, Ningchang Shi, Qian Zhou, JirongeSong, The Palace Museum (China)
The purpose of this article is to analysize the dark blue andlight green pigments particles fallen off from the Thangka of
Dhritarashtra portrait collected by the Palace Museum. The
crystal morphology and extinction phenomenon under single
polarized and polarized light of these particles were observed
through polarizing microscope. The chemical component andcrystal structure of these particles were measured throughtwo vibration spectroscopy methods including of laser Raman
spectrum and Fourier transform infrared spectrum. The results
showed that the dark blue particles were azurite and the lightgreen particles were malachite. The clear conclusion could supply
scientific basis for conservation of the Thangka of Dhritarashtra
portrait.

10030-34, Session 7

Measurement of high-temperature spectral
emissivity using integral blackbody
approach
Yijie Pan, Wei Dong, Hong Lin, Zundong Yuan, Pieter
Bloembergen, National Institute of Metrology (China)
Spectral emissivity is a critical material’s thermophysical property
for heat design and radiation thermometry. Specifically, for athermal protective material in an aerospace application such as
re-entry vehicle, hypersonic glide vehicle, its spectral emissivity
determines the heat exchange of the surfaces, and it directly
influences the heat design and corresponding optimization
process of the system. For a high temperature measurement
application, for example a liner pyrometer based radiation
thermometry, spectral emissivity directly influence the accuracyof results.
A prototype instrument based upon an integral blackbody
method was developed to measure material’s spectral emissivity
above 1000?. The system was implemented with an optimizedcommercial variable-high-temperature blackbody, a high speed
linear actuator, a linear pyrometer, and an in-house designed
synchronization circuit. The variable-high-temperature blackbody
had a graphic tube as an electrical heating furnace. A sample
was placed in a crucible at the bottom of the furnace, by which
the sample and the tube formed a simulated blackbody which
had an effective total emissivity greater than 0.985. During
the measurement, the sample was pushed to the end openingof the tube by a graphite rod which was actuated through apneumatic cylinder. The pushing process was fast. Therefore, thetemperature drop of the sample was small. A linear pyrometer
was used to monitor the brightness temperature of the sample
surface through the measurement. The corresponding optoconverted voltage signal was fed and recorded by a digital
multimeter.

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
A physical model was proposed to numerically evaluate thetemperature drop along the process. Tube was discretized asseveral isothermal cylindrical rings, and the temperature profileof the tube was measurement. View factors between sample
and rings were calculated and updated along the whole pushingprocess. The radiation heat transfer among the surfaces was
conducted. The actual surface temperature of the sample atthe end opening was obtained. Taking advantages of the abovemeasured voltage profile and the calculated true temperature,
spectral emissivity under this temperature point was calculated.
Graphite sample at 1000?, 1300?, and 1500?, respectively, wasmeasured to prove the validity of the method. The preliminary
result of sintered silicon carbide, carbon composite, and ceramic
thermal protection material were provided as well.

10030-35, Session 7

Analytic technology of infrared absorption
spectrum based on time-frequency
analysis
Xiyang Liu, Nan Gao, Hebei Univ. of Technology (China);
Zhenhui Du, Tianjin Univ. (China); Chao Chen, Zonghua
Zhang, Hebei Univ. of Technology (China)
Infrared absorption spectroscopy has been widely used in thefield of quantitative analysis. The overlapped spectral lines ofdifferent components make the component recognition andconcentration calculation of the mixture difficult to realize.
In order to solve this problem, in this paper the analytic
technology of infrared absorption spectrum was researched inorder to establish an effective, accurate and stable component
identification method. The derivative spectrum of directabsorption spectral line was calculated to eliminate the influenceof background and noise. The wavelet analysis method withappropriate wavelet basis and scale resolution was used tomake the time-frequency analysis of the derivative spectrum
to obtain the two dimensional time-frequency characteristics
matrix. The correlation analysis in both time and frequency
dimensions to the time-frequency characteristics matrix ofdifferent components and mixtures was researched to realize thecomponent identification in combination with the morphologicalcharacteristics of the derivative spectral line. Experimental
results show that the proposed method can effectively identify
the target component from the their mixture spectral line. The
research in this paper provides a method and technical route forsimultaneous detection and spectral analysis of multi-component.

data processing unit. Spectrometer detection wavelength ranged
from 400nm to 1000nm. After hyperspectral images of tomato
leaves being captured, it was needed to calibrate hyperspectral
images. This research used spectrum angle matching method andspectral red edge parameters discriminant method respectively
to identify diseased tomato leaves. Using spectral red edge
parameters discriminant method produced higher recognition
accuracy, the accuracy was higher than 90%. Research results
have shown that using hyperspectral imaging technology toidentify diseased tomato leaves is feasible, and provides thediscriminant basis for subsequent disease control of tomato
plants.

10030-37, Session 7

TDDA technology for high spatial
resolution SWIR InGaAs imaging
Yueming Wang, Shanghai Institute of Technical Physics of
the Chinese Academy of Sciences (China)
Infrared remote sensing imaging technology as one of thehigh-tech of today’s rapid development, more and more widelyused in weather forecasting, natural disaster detection, earth
environmental monitoring, navigation, agriculture, astronomy,
and other fields. Whether in civilian areas or astronomy research,study high sensitivity infrared detection imaging technology has
a positive significance. SWIR (shortwave infrared) has got more
and more attention because of its spatial resolution approaching
the level of visible light, through the fog ability.
High spatial resolution SWIR imaging often requires highframe frequency. If the frame frequency is too high, it could
cause the shortage of the image’s SNR (signal to noise ratio),
seriously affecting the image quality. Some foreign remotesensing satellites use image motion compensation technology
to increase SNR. But this requires additional control mechanism,
which increases system structure’s complexity and leads to scan
blindness. Digital TDA (time delay and accumulation) technology
is proposed in this paper to improve system’s SNR and image
quality.

10030-36, Session 7

This paper introduces the image motion compensation
technology and TDI (time delay and integration) technology,
analyzes the noise model of different remote sensing devices andcompares the difference of PA (pixel accumulation) technology,
digital TDI technology and digital TDA technology. A prototypeof SWIR imaging system based InGaAs detector is designed,
which demonstrates digital TDA technology. The experimentresult indicates digital TDA technology can increase system’s SNRof the square root of TDA’s stage and improve image’s uniformity.
The results in this paper are helpful for the improvement andapplication of high spatial resolution SWIR imaging technology.

Using hyperspectral imaging technology
to identify diseased tomato leaves

10030-38, Session 7

Cuiling Li, Xiu Wang, Xueguan Zhao, Zhijun Meng, Wei
Zou, Beijing Academy of Agriculture and Forestry
Sciences (China)

Tunable mid-infrared emission fromacetylene-filled hollow-core fiber

In the process of tomato plants growth, due to the effect ofplants genetic factors, poor environment factors, or disoperationof parasites, there will generate a series of unusual symptoms
on tomato plants from physiology, organization structure andexternal form, as a result, they cannot grow normally, andfurther to influence the tomato yield and economic benefits.
Hyperspectral image usually has high spectral resolution, notonly contains spectral information, but also contains the image
information, so this study adopted hyperspectral imaging
technology to identify diseased tomato leaves, and developed asimple hyperspectral imaging system, including a halogen lamp
light source unit, a hyperspectral image acquisition unit and a

264

SPIE Photonics Asia·

Zefeng Wang, Zhiyue Zhou, Zhixian Li, Naiqian Zhang,
Yubin Chen, National Univ. of Defense Technology (China)
Mid-infrared fiber lasers have wide application in defense,
security, atmosphere monitoring, and medicine, and haveattracted enormous attentions. Usually, due to the low damage
threshold, solid-core fiber lasers lack the ability to provide thesame power levels as conventional gas lasers, which can reach
MW levels in chemical gas lasers. Because of nonlinear effects,
the spectral linewidth of light generated in glass fibers will
broaden at high powers. Additionally because the number ofrare earth materials is limited, only certain laser wavelengths areavailable. Gas lasers have been demonstrated to be an effectwww.spie.org/pa·

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV
method to generate mid-IR emission. In traditional gas cells theeffective interaction length is very short and the system is bulky
and cumbersome, limiting the applications of these lasers. The
advent of hollow core fibers and their excellent properties makeit possible to develop a novel type of laser, fiber gas lasers. In ourprevious works, we have reported firstly efficient diode-pumped
3?m mid-infrared emission from acetylene-filled hollow-core fiber.
Here, we use a modulated, two-stage Er-doped fiber amplified,narrowband, tunable 1.5 ?m diode laser as the pump, and awavelength, pulse width, repetition rate tunable mid-infrared
single-pass fiber acetylene laser is demonstrated for the firsttime. The wavelength is step-tunable in the range of 3.1~3.2 ?mwhen the pump laser is precisely tuned to different absorption
lines of P-branch of acetylene. The shortest pulse width is about
10 ns and the highest repetition rate is several tens of MHz, which
is limited by the acousto-optical modulator.

10030-39, Session 7

The initial design of LAPAN’S IR
microbolometer using mission analysis
process
Bustanul Arifin, Irwan Priyanto, Andi Mukhtar Tahir, Firman
Bakti, Indonesia National Institute of Aeronautics andSpace (Indonesia)
As new player in Infra Red (IR) sector, uncooled, small, andlightweight IR Micro Bolometer has been chosen as one of
payloads for LAPAN’s next micro satellite project. Driven
the desire to create our own IR Micro Bolometer, mission
analysis design procedure has been applied. After tracing all
possible missions, the Planck’s and Wien’s Law for black body,
Temperature Responsivity (TR), and sub-pixel response had beenutilized in order to determine the appropriate spectral radiance.
The 3.8 – 4 ?m wavelength were available to detect wild fire
(firest fire) and active volcanoes, two major problems faced byIndonesia. In order to strengthen and broaden the result, iteration
process had been used throughout the process. The analysis,
then, were continued by calculating Ground pixel size, IFOV
pixel, swath width, and focus length. Meanwhile, regarding ofresolution, at least it is 400 m.
The further procedure covered the integrated of optical design,wherein we combined among optical design software, Zemax,
with mechanical analysis software (structure and thermal
analysis), such as Nastran and Thermal Desktop / Sinda
Fluint. The integration process was intended to produce highperformance optical system of our IR Micro Bolometer that canbe used under extreme environment. The results of all thoseanalysis, either in graphs or in measurement, show that the initialdesign of LAPAN’S IR Micro Bolometer meets the determined
requirement. However, it still needs the further evaluation(iteration). This paper describes the initial design of LAPAN’s IR
Micro Bolometer using mission analysis process

10030-50, Session 7

A design on low noise imaging circuit for
SWIR sensor
Ben Fan, Zhixue Han, Fei Ma, Beijing Institute of Space
Mechanics and Electricity (China); Shuli Dong, Beijing
Institute Of Space Mechanics & Electricity (China)
SWIR(Short Wave Infrared) imaging is an important imaging
technology in space remote sensing. According to thecharacteristics of SWIR detector, the whole scheme of low noise
imaging circuit is presented. For the certain key circuit that is
noise sensitive in the design, such as bias generation circuit,

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Follow us on:an analysis on noise sources and the calculation of theoreticalnoise value on actual circuit that is usually ignored in previous
researches are proposed in order to estimate the level of circuit
noise and find way to optimize the circuit to reduce noise.The
structure of analog filter amplifier circuit is also analyzed byintroducing noise-factor analytic approach and based on theanalysis result some design principles of the circuit are proposed.
The noise suppression methods in the design are separated
analyzed in both time suppression and space suppression, somespecific methods for these two kinds of measures are listed.
The finally experiment results indicate that the low noise designof imaging circuit based on above methods is reasonable andeffective, the circuit has a higher SNR and could work normally inhome temperature with a clear imaging, the whole design meetsthe original requirement on low noise. This low noise circuit for
SWIR detector and its methods to analyze and calculate thetheoretical noise value are valuable examples for future similar
designs.

10030-40, Session 8

Optical feedback effects on terahertz
quantum cascade lasers: modelling andapplications (Invited Paper)
Aleksandar D. Raki?, Yah Leng Lim, Thomas Taimre, Gary
Agnew, Xiaoqiong Qi, Karl Bertling, She Han, The Univ.
of Queensland (Australia); Stephen J. Wilson, The Univof Queensland (Australia); Andrew Grier, Zoran Ikonic,
Alexander Valavanis, Paul Dean, Aleksandar Demic, James
Keeley, Lianhe H. Li, Edmund H. Linfield, A. Giles Davies,
Univ. of Leeds (United Kingdom); Paul Harrison, Sheffield
Hallam Univ. (United Kingdom); Tarl W. Prow, The Univ. of
Queensland School of Medicine (Australia); Dragan Indjin,
Univ. of Leeds (United Kingdom); H. Peter Soyer, The Univ.
of Queensland School of Medicine (Australia)
Terahertz (THz) quantum cascade lasers (QCLs) are compact
sources of electromagnetic radiation in the 1–5 THz frequency
range with significant potential for applications in sensing,imaging and communications due to their ability to generate
coherent, continuous-wave (cw) and high-power pulsed emission
with quantum noise-limited linewidths.
In this work we will discuss the effects of optical feedback on the
dynamics of THz QCLs and explore the relationship between theelectrical, optical and thermal processes in these devices.
Laser feedback interferometry (LFI) with THz QCLs is a novel
sensing technique, well-suited to the development of compact
THz sensing systems, in which the radiation is reflected back into
the QCL cavity from an external target. The retroinjected wave
gives rise to measurable changes in the electronic and opticalbehavior of the laser, through a phenomenon frequently referred
to as self-mixing.
Most THz LFI systems to date have employed THz QCLs
operating in the continuous-wave cryogenic regime. In this work
we will discuss the potential for the development of pulsed THz
LFI techniques, which would unlock pathways to new applications
in higher-temperature THz QCL imaging, long-range screening,and materials identification.
We will then focus on the interferometric schemes for biologicaltissue imaging due to its sensitivity to hydration levels, as aconsequence of high absorption of THz radiation in water. We willshow that the confocal nature of the QCL LFI systems with theirinnate capacity for depth sectioning makes them suitable for skindiagnostics with well-known advantages of more conventional
confocal microscopes.

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265

Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-41, Session 8

to the antennas. Both the focusing and imaging properties aredemonstrated. This designed THz multi-focus lens performs overa broad frequency band of 0.3–1.1 THz. This type of transmissive
metasurface serves as an attractive alternative to conventional
diffractive optical elements based on its broadband operation,
small area, ease of fabrication, and low cost.

Localized spoof surface plasmon
resonances at terahertz range
Lin Chen, Li Chen, XiaoFei Zang, Yan Peng, Yiming Zhu,
Univ. of Shanghai for Science and Technology (China)
We theoretically demonstrated and experimentally verified
terahertz multipolar spoof localized surface plasmons(LSP)
modes by introducing symmetry breaking in a textured metallic
disk in normal incidence. Through exact numerical simulations,at normal incidence, we show the emergence and near-field
properties of these multipolar spoof LSP resonances in two
asymmetrical metal particles: a defective corrugated metallic
disk structure and a hybrid structure consisted of a C-shaped
resonator and a corrugated metallic disk. Their occurrence
and spectral properties are measured and characterized
experimentally by using terahertz time domain spectroscopy(THz-TDS), showing an excellent agreement with theoreticalpredictions.

10030-42, Session 8

Completely evolution of Gouy phase shift
in terahertz wave
Yan Peng, Tao Geng, Yiming Zhu, Univ. of Shanghai for
Science and Technology (China)
We experimentally and theoretically investigate the Gouy
phase shift of the longitudinal and transverse terahertz wave
in the entire focal region. By comparing the pulses shape andorientation before and after the focus, we find that the complete
Gouy shift for the longitudinal field components is same to thatof the transverse field components, with the value of π. The only
different between them is their phase difference π/2. Additionally,
we found that an external longitudinal electric field (-6~+6 kV)
can be used to control the time-domain waveform and then thecorresponding Gouy phase shift. These results have important
implications for the near-field optical microscopy and superresolution imaging.

10030-43, Session 8

Terahertz beam shaping with metasurface
Jingwen He, Harbin Institute of Technology (China) and
Capital Normal Univ. (China); Sen Wang, Harbin Instituteof Technology (China); Yan Zhang, Capital Normal Univ.
(China)Metasuface is composed of a subwavelength optical antenna
array, which can be used to modulate the phase and amplitudeof the cross-polarized scattered wave. Based on this principle,
we design some terahertz (THz) beam shapers, such as THz
ring-Airy beam shaper and THz multi-focus lens. Each beam
shaper consists of gold C-shaped slot antennas with various
opening angles and azimuthal angle of the axis of symmetry. A
THz holographic imaging system is utilized to measure the fieldof the generated beams. The ring-Airy beam shaper is designedby replacing phase and amplitude of its initial electric field withthe corresponding antennas. In the experiment, an abrupt focus
following a parabolic trajectory is subsequently observed. Thismethod can be expanded to other wavebands, such as the visible
band, for which the ring-Airy beam shaper can replace traditional
computer-generated holography to avoid undesirable multiple
diffraction orders. The phase distribution of the multi-focus lens
is obtained by using the Yang-Gu algorithm and then encoded

266

SPIE Photonics Asia·

10030-44, Session 9

Terahertz magnetic and electric Mie
resonances of an all-dielectric onedimensional grating and their sensing
capability (Invited Paper)
Yuping Yang, Minzu Univ. of China (China)
Here, high-resolution resonant phenomena in a silicon-based,
1D grating are theoretically and experimentally demonstrated
at terahertz frequencies. The periodic grating used in theexperiment was fabricated on a double-side polished Si wafer
with a length, period, width, and thickness of 5000, 205, 110
and 110 m, respectively.A series of high-qualify Mie resonanceswere excited in the all-dielectric grating, and displayed strong
frequency-selection and polarization-sensitivity behaviors.
For the application of the resonator as a sensor, all 105-m thickgaps between the silicon pillars are filled by a dielectric layer
with refraction index ranging from 1.0 to 2.0 at =0 and 20 S/m.
Simulations show that the position, intensity and linewidthof the second TE Mie resonance explicitly dependent on the
dielectric condition of surrounding media with the increased
redshift in wavelength and broadening in linewidth when therefraction index increases. In case of =20 S/m, the intensity ofthe transmission dip is also much sensitive to the change of therefraction index.

10030-46, Session 9

Gas trade detection with cavity-enhanced
absorption spectroscopy: a review of
CEAS’ process
Liu Siqi, Zhongqi Tan, National Univ. of Defense
Technology (China)
Cavity-enhanced absorption spectroscopy (CEAS) is atechnology that uses cw laser to directly detect substances’absorption spectrum with a high finesse optical cavity and it isused to detect or calculate samples’ parameters, such as species,
concentrations and absorption cross section. It was found out
in 1998 by R. Engeln or A. O’Keefe for improving sensitivity ofCavity Ring-down spectroscopy(CRDS). This technology has
extraordinary detection sensitivity, high resolution and goodpracticability, so it is projected to be use in many fields at near
future, such as clinical medicine, gas detection and basic physics
research. In this paper, we present the basic theory of CEAS
and its development over the past two decades. First, the key
points of CEAS, such as optical cavity, optical source and gas
cells, would be discussed in this paper. Next, we would introduce
the newest research progresses in labs. And finally, we would
simply compare the CEAS with other detection technologies andpredicate of the CEAS’s development direction in the future.

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Conference 10030: Infrared, Millimeter-Wave,
and Terahertz Technologies IV

10030-47, Session 9

Ripple FPN reduced algorithm based on
temporal high-pass filter and hardware
implementation
Yiyang Li, Weiqi Jin, Shuo Li, Beijing Institute ofTechnology (China); Zhipeng Zhang, Tianjin JinhangInstitute of Technical Physics (China)
Cooled infrared detector arrays always suffer from undesired
Ripple Fixed-Pattern Noise (FPN) when observe the scene ofsky. The Ripple Fixed-Pattern Noise seriously affect the imaging
quality of thermal imager, especially for small target detection
and tracking. It is hard to eliminate the FPN by the Calibration
based techniques and the current scene-based nonuniformity
algorithms. In this paper, we present a modified space low-passand temporal high-pass nonuniformity correction algorithm using
adaptive time domain threshold (THP&GM). The threshold isdesigned to significantly reduce ghosting artifacts based on thelocal gray-level gradient. We test the algorithm on real infraredin comparison to several previously published methods. Thisalgorithm not only can effectively correct common FPN suchas Stripe, but also has obviously advantage compared with thecurrent methods in terms of detail protection and convergence
speed, especially for Ripple FPN correction. Furthermore,
we display our architecture with a prototype built on a Xilinx
Virtex-5 XC5VLX50T FPGA. The hardware implementation of thealgorithm based on FPGA has two advantages: (1) low resources
consumption, and (2) small hardware delay(less than 20 lines).
The hardware has been successfully applied in actual system.

10030-70, Session 9

Multicasting of signal-carrying Gaussianmode to multiple orbital angularmomentum (OAM) modes (Invited Paper)
Shuhui Li, Jian Wang, Huazhong Univ. of Science andTechnology (China)
Recently, orbital angular momentum (OAM) beams haveunlimited orthogonal states (in principle, l can take arbitrary
integer number ranging from -∞ to +∞), showing great potential
to multiplex a large number of OAM beams and tremendously
increase the available information bandwidth. Lots of research
efforts have been devoted to increase the transmission capacity
and spectral efficiency in both free-space and fiber-opticalcommunication systems by employing OAM multiplexing. In
addition to OAM multiplexing, OAM-based networking functions
such as data exchange, add/drop multiplexing and multicasting
have also proposed to advance the usefulness of OAM for multiuser communication applications. Among these functions, OAM
multicasting is a very important one which can duplicate dataof one single channel onto multiple OAM channels, without theneed of detection and remodulation processes. In this paper, we
review our recent works on N-fold orbital angular momentum(OAM) multicasting links. By exploiting optimized complex phasepattern, the data information carried by an input Gaussian modecan be copied and delivered to multiple OAM modes which are
distinguishable from each other owing to their own distinct
spiral phase fronts. Experiment demonstration of 1-to-34 OAM
multicasting, adaptive power-controllable OAM multicasting, andcompensation of a distorted OAM multicasting link are presented.
It is expected that the proposed OAM multicasting schemes,
facilitating flexible and efficient OAM manipulation, may findwide potential use in future grooming OAM communications andnetworks.

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