2012
5–7 November 2012

Technical Abstracts
www.spie.org/pa

Location
Beijing International Convention Center
Beijing, China

Conference
5–7 November 2012

1A  Sponsored by:

Cooperating Organizations:
Tsinghua University
Peking University
Zhejiang University
Beijing Institute of Technology
Beijing University of Posts andTelecommunications
University of Science and Technology
of China
Tianjin University
Nankai University
Changchun University of Scienceand Technology
University of Shanghai for Scienceand Technology
Capital Normal University
Huazhong University of Science andTechnology
Beijing Jiaotong University
Shanghai Institute of Optics and Fine
Mechanics, CAS
Changchun Institute of Optics Fine
Mechanics and Physics, CAS
Institute of Semiconductors, CAS
Institute of Optics and Electronics, CAS
Institute of Physics, CAS
Shanghai Institute of Technical 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

General Chairs:

Supported by:
China Association for Science andTechnology (CAST)
Department of Information of National
Nature Science Foundation, China(NSFC)

Guangcan Guo, University of Science andTechnology of China

Eustace Dereniak, SPIE President,
University of Arizona

Bingkun Zhou, COS President,
Tsinghua University

Local Organizing Committee Co-Chairs:
Guoqiang Ni, Beijing Institute of Technology
Shusen Xie, Fujian Normal University
Xiaomin Ren, Beijing University of Posts andTelecommunications
Ying Gu, PLA General Hospital
Huilin Jiang, Changchun University of
Science and Technology

General Secretary:
Qihuang Gong, Peking University

General Co-Chairs:
Arthur Chiou, National Yang-Ming University
Zhizhan Xu, Shanghai Institute of Optics andFine Mechanics, CAS
Jianlin Cao, China Ministry of Science andTechnology
Junhao Chu, Shanghai Institute of TechnicalPhysics, CAS

Technical Program Chairs:
Songlin Zhuang, University of Shanghai for
Science and Technology
Xingde Li, Johns Hopkins University

Technical Program Co-Chairs:
Qiming Wang, Institute of Semiconductors,
CAS
Xu Liu, Zhejiang University
Daoyin Yu, Tianjin University
Qihuang Gong, Peking University
Tianchu Li, National Institute of Metrology
Wei Huang, Nanjing University of Posts andTelecommunications

Local Organizing Committee Chair:

Local Organizing Committee:
Yan Li, Chinese Optical Society/Peking
University
Zhiping Zhou, Peking University
Changhe Zhou, Shanghai Institute of Optics
and Fine Mechanics, CAS
Qingming Luo, Huazhong University of
Science and Technology
Chongxiu Yu, Beijing University of Posts andTelecommunication
Hongda Chen, Institute of Semiconductors,
CAS
Yongtian Wang, Beijing Institute ofTechnology
Yiping Cui, Southeast University
Xuping Zhang, Nanjing University
Feijun Song, Daheng Corp.
Cunlin Zhang, Capital Normal University
Yanting Lu, Nanjing University
Yuejin Zhao, Beijing Institute of Technology
Chunqing Gao, Beijing Institute ofTechnology
Tiegen Liu, Tianjin University
Xiaocong Yuan, Nankai University
Weimin Chen, Chongqing University
Zhongwei Fan, Academy of Opto-electronics,
CAS
Hanyi Zhang, Tsinghua University
Lan Wu, Zhejiang University
Yongsheng Zhang, University of Science andTechnology of China
Hong Yang, Peking University
Xiaoying Li, Tianjin University
Lin Zhai, Chinese Optical SocietyContents

Click on the conference title andyou will be taken to the page8551

High-Power Lasers and Applications VI. .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 48552

Semiconductor Lasers and Applications V. .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 16

8553

Optics in Health Care and Biomedical Optics V . .  .  .  .  .  .  .  .  .  .  . 26

8554

Quantum and Nonlinear Optics II. .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 54

8555

Optoelectronic Devices and Integration IV . .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 68

8556

Holography, Diffractive Optics, and Applications V . .  .  .  .  .  .  .  . 85

8557

Optical Design and Testing V . .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 101

8558

Optoelectronic Imaging and Multimedia Technology II . .  .  .  . 123

8559

Information Optics and Optical Data Storage II . .  .  .  .  .  .  .  .  .  . 146

8560

LED and Display Technologies II. .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 153

8561

Advanced Sensor Systems and Applications V. .  .  .  .  .  .  .  .  .  .  . 158

8562

Infrared, Millimeter-Wave, and Terahertz Technologies II . .  . 174

8563

Optical Metrology and Inspection for
Industrial Applications II. .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 193

8564

Nanophotonics and Micro/Nano Optics. .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . 205

SPIE would like to express its deepest appreciation to thesymposium chairs, conference chairs, program committees,
session chairs, and authors who have so generously given theirtime and advice to make this symposium possible.
The symposium, like our other conferences and activities,
would not be possible without the dedicated contributionof our participants and members. This program is based oncommitments received up to the time of publication and issubject to change without notice.

Conference 8551:
High-Power Lasers and Applications VI
Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8551 High-Power Lasers and Applications VI

8551-2, Session 1

8551-4, Session 1

Theoretical and experimental investigationof Rb-Ar excimer pumped alkali laser
characteristics

Competition between spontaneous radiationand ionization in the process of resonanceenhanced multi-photon ionization

Desheng Yue, Wenyu Li, Hongyan Wang, Zining Yang, Xiaojun
Xu, National Univ. of Defense Technology (China)

Guiyin Zhang, Haiping Li, Haiming Zheng, North China ElectricPower Univ. (China); Hui Ji, North China Electric Power
University (China)

Diode Pumped Alkali Laser (DPAL) has been identified as one of themost promising high energy lasers due to its combination of solidstate laser’s compactness, high efficiency and gas laser’s easy thermal
management. However, commercial diode laser stack typically emitswith spectral widths of 1000 GHz, which must be narrowed down 2orders magnitude to match alkali atom’s absorption bandwidth. And
the small hydrocarbon molecule added in DPAL to accelerate P3/2 andP1/2 state mixing may react with alkali atoms at elevated temperature.

With the coming forth of high power laser, the technique of resonanceenhanced multi-photon ionization (REMPI) spectroscopy has become
one of the important methods for studying the high excited energy
levels and the dynamics of chemical reaction of atoms and molecules.
Photo-ionization probability is an important factor in the practicaluse of REMPI. To a certain experimental condition, it depends on thecompetition between spontaneous radiation and ionization of theexcited particles. In this work, we investigate the influence of laser
resonance detuning, Rabi frequency and ionization rate on spontaneousradiation and ionization in the process of REMPI with the theory ofdensity matrix equation. A model of three energy level system isadopted. It is found that the spontaneous radiation and ionization
probability increase with the decrease of laser resonance detuning.
They get to the maximum when resonance detuning is zero. The line
width of spontaneous emission will decrease with the increase ofionization rate due to the competition between spontaneous radiationand ionization. In addition, the spontaneous radiation and ionization
probability increase with Rabi frequency until gets to saturation. Laser
resonance detuning has no influence on the saturation value. It only
influences the Rabi frequency for saturation. If Rabi frequency increases
further after saturation, the spontaneous radiation will decrease
because of the phenomena of energy level splitting in strong laser field.
Now that resonant absorption and large laser intensity can increase theionization probability greatly, so we must select suitable laser frequency
and large laser intensity in the practical use of REMPI, in order to get
optimum detection result.

Recently, Excimer Pumped Alkali Laser (XPAL) was proposed to solve
the two disadvantages. By pumping alkali-rare gas atomic collisionpairs, named excimer’s broad blue spectral satellites, commercial
diode stacks could be directly used, and the hydrocarbon would not beneeded any more. The Cs-rare gas XPAL had been thoroughly studied
by group of University of Illinois with short pulsed dye laser, while the
Rb-rare gas XPAL’s report is rare.
In this paper, theoretical and experimental study of Rb-Ar four level
XPAL was put forward. A self-made 10 nanosecond pulsed opticalparametric oscillator was acted as the surrogate pump source, andsuccessful lasing in 780nm was realized in a broad spectra range
centered at 755nm. A time dependent rate equation model was carriedout to study the Rb-Ar laser’s threshold and cw running characteristics.
It was found that due to the extreme low absorption cross-section ofblue wing satellites, much higher pump intensity than DPAL is needed
to get population inverted. To realize high efficient cw running, highefficient absorption of pump light must be assured.

8551-3, Session 1
8551-5, Session 2

Gas dynamic effect in high-energy fluid
diode pumped alkali vapor laser

Variation of thermal lens curvature type
between the convex and the concave lensfor zigzag slab laser

Yao Xu, Wenyu Li, Hongyan Wang, Zining Yang, Xiaojun Xu,
National Univ. of Defense Technology (China)
In the field of high energy lasers, diode pumped alkali laser has become
one of the high lights in recent years. Our team has done abundantresearches on spectral linewidth narrowing for diode pumping lasers,
side-pumped DPAL model setting with flowing medium, etc, boththeoretically and experimentally. And we obtained 795nm Rb vapor
laser by using a volume Bragg grating stabilized diode laser bar on Jul,2011.

Xing Fu, Qiang Liu, Mali Gong, Tsinghua Univ. (China)
In this letter, we investigate the thermal lensing along the directionof heat removal in a zigzag slab laser by numerically computing its
temperature distribution, the OPD profile and the focal length of thethermal lens. Particular attention is paid to the dependence of thecurvature type of the thermal lens on the number of bounces. As thenumber of bounces increases consecutively, the curvature type ofthe thermal lens in the slab thickness direction oscillates between
the concave lens and the convex one, but not in an alternate manner.
The reason is disclosed that for the convex lens case, the averagetemperature along the route, through which the ray on the edge of themain lobe aperture travels is much lower than that at the center. The
formation of the concave lens can be well explained in a similar way. In
addition, we conclude that the beamlet with a larger number of bounces
experiences weaker thermal lensing but more serious wavefront
deformation due to the large side lobe portion in the curve of optical
path difference.

With the aim to improve the power of DPAL, one of the hotspots today
is to solve the heat sinking problem by using cycled flowing medium
method. However, gas dynamic effects haven’t been taken into
consideration in all these methods. In this paper, a one dimensional
heated pipe flow model is set to discuss the influence that alkali active
media heat source brings to the thermodynamics parameters of thegas. We discover that due to the small size of the volume source, theheat giving out per volume is huge which notably affects the velocity,temperature and the density of the active medium along the direction of
the flow. As a result, the rectangular cross section of the pipe needs tobe redesigned. With the help of fluid dynamics software based on limit
volume method, we calculate the influence a MW light field brings tothe volume source and analyze the boundary layer effect. These work
can be a reference to the researches on high energy fluid diode pumped
alkali vapor laser.

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The analysis and the discussion provide a good reference for thedesign of slab parameters and the selection of the number of bounces.
Furthermore, multiple zigzag slabs with different curvature types ofthermal lenses can be placed in a cavity or lined up as a multi-stage
amplifier, which may compensate the thermal lensing and the wavefront
deformation, thus improving the beam quality.

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Conference 8551:
High-Power Lasers and Applications VI

8551-7, Session 28551-9, Session 2

Nonlinear imaging properties of two parallel
gain-typed wirelike scatterers

Low threshold cholesteric liquid crystal
based laser with temperature-tunablecharacteristics

Jie Huang, Yonghua Hu, Hunan Univ. of Science andTechnology (China)
Based on the optical path model for nonlinear imaging, we
systematically investigated the propagation of flat-topped Gaussian
beam which is modulated by two parallel gain-typed wirelike scatterers
through computer simulation. It is found that hot image for eachscatterer can be formed, with the hot image plane several centimetersbehind the predicted conjugated plane obtained by the approximate
theory for attenuation-typed scatterers. When compared with the casewhere only one scatterer exists, the hot image intensity can be relatively
smaller under certain parameters. Moreover, it is found that the object
distance, i.e. the distance from the scatterer plane to the incident
surface of the Kerr medium slab, has an important influence on the
propagation properties and results in some new phenomena. Firstly,
under certain object distances, the evolution of the maximum intensityof the beam has one prominent peak before that for hot image, where
the on-axis location is dozens of centimeters ahead of the hot image
plane, and as the size of the scatterers increases, the distance between
these two planes decreases at first, then increases and decreases atlast; the value of this peak increases at first and then decreases. The
intensity distribution corresponding to this peak shows that, there isan intense fringe, which is the most intense fringe in the plane, at the
middle point of the line connecting the two scatterers, indicating that it
is a unique result of the interaction of the two scatterers. Second, undersome other object distances, the evolution of the maximum intensityof the beam also has one prominent peak before that for hot image,but there are two fringe pairs corresponding to each scatterer in theintensity distribution.

8551-8, Session 2

In-situ measurement based on priorcalibration with analogist samples for laser
cladding
Jichang Liu, Yaoting Wu, Lei Wang, Hunan Univ. (China)
A system, consisting of a CCD camera, a frame grabber and acomputer, is developed to in-situ measure the molten pool parameters
during laser cladding based on prior calibration with analogist samples.
The signals acquired during laser cladding vary with change insubstrate material or clad material, so that, in order to gain the true dataof the molten pool parameters, calibration of the instrument must be
performed for every set of substrate and clad materials. In this study,
a new strategy for on-line acquisition of molten pool parameters ispresented. Before measurement of the objective molten pool, cladding
is performed to get some analogist samples of the same materials
as those used to generate the objective molten pool. The width of acertain segment of the clad bead on the analogist sample is gauged
to calibrate the CCD camera-grabbed image of the molten pool which
solidify to this segment of the clad bead. The pool width in the grabbed
image can be confirmed to the gauged bead width times the scaling
because the width of the clad bead segment must be equal to thewidth of the related pool. It is assured which type of area in the grabbed
image is located on by the pool, and the CCD is calibrated for this setof substrate and clad materials. After calibration, the CCD system isapplied to in-situ measure the molten pool parameters during laser
cladding. In the presented experiments, the measured values agree wellwith the actual ones.

Yongjun Liu, Feiru Wang, Xiaoqi Liu, Harbin Engineering Univ.
(China)In cholesteric liquid crystal based laser, the periodic helical structuresof cholesteric liquid crystal is used to replace resonator and laser dyes
to laser medium.With proper orientation treatment and pump light,
high monochromaticity laser of 5nm has been gained. the thresholdand power are discuss in the paper. By changing pumping light, exit
light gets weak, then the threshold measurement of laser is done. To
gain high power and low threshold laser, improvement measures areproposed and texted, such as experiment temperature, thicknessof liquid crystal layer and angle of pumping light.Among these, theexperiment temperature also affect the wavelength of exit light bychanging helical pitch and refractive index of cholesteric liquid crystal.
At the temperature from 30°C to 43°C, the wavelength changes
observantly ,gradually and slowly. At the same time the transmissionsof cholesteric liquid crystal at different temperature are texted to verify
relationship between the wavelength of exit light and transmissions
spectrum. Though this, we can conclude the wavelength of exit lightalways at the right fall edge of transmissions spectrum. Low thresholdcholesteric liquid crystal based laser with temperature-tunablecharacteristics can be obtained by altering the experiment condition
above.

8551-10, Session 2

Analysis of convective heat transfer
coefficient for SG-II Prototype
Zhiyuan Ren, Jianqiang Zhu, Zhigang Liu, Hongbiao Huang,
Shanghai Institute of Optics and Fine Mechanics (China)
The forced convective heat transfer coefficients during the period ofthermal recovery for laser slab on the multi-segment amplifies of SG-?isanalyzed. We have simulated the parameters including coolant gas andthe geometry of amplifier with computational fluids dynamics (CFD)
method. Based on the simulated results, we attained the optimized
parameters such as the flow rate, the temperature and the type of gas,
the diameter of inlet jet, the quantity of inlet jet, the distance between
the inlet jet and the laser slab, the spray angle of inlet.

8551-11, Session 3

Ultra-fast ytterbium fiber laser operating at
low repetition rate (Invited Paper)
Jean-Bernard Lecourt, Simon Boivinet, Yves Hernandez,
Multitel A.S.B.L. (Belgium)
Ultra-fast lasers operating at 1 µm have been used in a lot of industrial
applications such as micromachining. Among all the available sources,
the recently developed All Normal Dispersion (ANDi) mode-lock fiber
lasers are of particular interest because they are compact, alignmentfree and able to deliver high pulse energy. In this study, we report a
Polarization Maintaining (PM) ANDi all-fibered laser passively modelocked with a SESAM exhibiting high modulation depth (25%) andultra-fast relaxation time (~500 fs). We have focused on the possibility tooperate with both ultra-short pulses (<1 ps) and low repetition rate (<10MHz), thus a great care has been taken to manage chromatic dispersion
and spectral filtering in the cavity. We observed that a strong spectral
filtering is required to operate with stable and ultra-short optical pulses
in a highly dispersive cavity. The built laser is a unidirectional ringcavity composed of PM components (optical coupler, multiplexer andcirculator), PM fiber Bragg gratings and PM Yb-doped fiber pumped

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Conference 8551:
High-Power Lasers and Applications VI
by a single-mode 976 nm laser diode. The repetition rate has been set
to 7,7 MHz, corresponding to the cavity roundtrip. The laser delivers
picoseconds highly chirped optical pulses that are compressible
down to about 800 fs (Fourier transform limit). The optical spectrum iscentered at 1065 nm with a bandwidth of 2 nm. The output power is 4,7mW leading to a pulse energy of 0,6 nJ.

Yb3+-doped fiber lasers (YDFL) have an important advantage ofpossessing a broad emission spectrum range (970 nm-1200 nm). Mostof recent research of YDFL focuses on the wavelength range between
1030-1120 nm. Exploring the operation of long wavelength (> 1120nm)
may increase the number of applications. For example, YDFL operating
at 1150-1180 nm is quite attractive for creation of yellow light sources
for medicine and astronomy by frequency doubling technique. YDFLs
with the emission wavelengths in the wavelength 1120-1160 nm can be
defiantly used as pump source for Ho-doped fiber laser emitting in the
2 µm region.

8551-12, Session 3

Single mode linearly polarized high power
fiber laser at 1120 nm

In this paper, we will report an YDFL operates at a long-wavelengthof 1137 nm. The laser cavity consists of a pair of fiber Bragg gratings(FBG) and a piece of highly-doped Yb3+-doped fiber. The central
wavelength of both FBG is 1137nm, and the reflectivity of which is
99.62% and 39.74%, respectively. The highly-doped Yb3+-doped fiber
had a core diameter of 5 µm and cladding diameter of 125 µm, theabsorption coefficient of this highly-doped Yb3+-doped fiber could be
more than 500 dB/m at 976 nm. The laser cavity is pumped by an YDFL
operates at 1040 nm. Experimental results show that the YDFL could
work at long-wavelength band and operates at 1137 nm efficiently. The
1137 nm YDFL had a pump-limited maximal output power of 276 mW
and the ASE centered at 1080 nm is suppressed by a factor of morethan 20 dB.

Jianhua Wang, Shanghai Institute of Optics and Fine Mechanics(China) and National Univ. of Defense Technology (China); Lei
Zhang, Jinmeng Hu, Yan Feng, Shanghai Institute of Optics andFine Mechanics (China); Jinbao Chen, National Univ. of Defense
Technology (China)
We will report our recent progress in developing 1120nm Yb-doped
fiber laser. QCW fiber laser at 1120nm with about 100 W peak power
was realized, which was successfully used for achieving single
frequency Raman fiber amplifier at 1178nm with a peak power of 40W.
The polarization extinction ratio of 16dB was measured. At the sametime, high power fiber amplifier at 1120nm will be also researched for
Raman amplifier. As far as we know, this is the first detailed reportabout 100W-class Yb-doped linearly polarized single mode fiber laserat 1120nm. In this paper, we will detailed analyze the factors impacting
on Yb-doped fiber emitting at 1120 nm.

8551-15, Session 3

Femtosecond fiber lasers for biomedical
solutions
Jian Liu, Lihmei Yang, PolarOnyx, Inc. (United States)

8551-13, Session 3

For the past few years, femtosecond (fs) fiber lasers have been growing
in popularity over conventional solid state lasers. A turn-key fs fiber
laser solution offers unprecedented features of compactness, lowmaintenance, and low power consumption. Many types of fs fiber lasers
have been developed for biomedical applications covering opticalcoherence tomography (OCT), multi-photon imaging (MPI), coherent
anti-stoke Raman spectroscopic imaging (CARS), Raman spectroscopic
imaging, nonlinear spectroscopy, confocal microscopy, cell dissection,nano surgery, and more.

High average/peak power all fiber pulse
laser from picosecond to microsecond
regimeXiaolin Wang, Pu Zhou, Zhiqun Gong, Hanwei Zhang, Rumao
Tao, Xiaojun Xu, National Univ. of Defense Technology (China)

Several methods have been used to generate passive mode locking
femtosecond pulses for fiber lasers: nonlinear polarization rotation,
carbon nanotube, and saturable absorbing mirrors SESAM. All thesemethods can obtain stable mode locking operation with a reasonable
performance and qualification. By adding amplifiers after the seed fiber
oscillator and in cooperating with pulse shaping, spectral shaping andpolarization shaping techniques, output power from 100’s of mW to
100’s Watts can be obtained with pulse duration compressible to lessthan 100 fs. For majority of biomedical applications, power level ofseveral Watts is sufficient while most of the requirements are within 100
mW.

We demonstrated four types of high power/energy all fiber pulse laser inmaster oscillation-power amplification configuration at 1µm wavelengthfrom ps to ?s regime. The picosecond pulsed amplifier is based onan active phase modulated mode-locked seed laser, and more than
196.5W average power, 0.96?J pulse energy at ps regime is obtained.
The 10ns amplifier is based on intensity modulated single-frequency
pulse seed, and 0.5mJ pulse energy, 32.4kW peak power pulses at
15ns regime is obtained, which is considered to be the highest peak
power in single-frequency pulse fiber laser. The 100ns pulse amplifier isbased on a Q-switched seed laser, 6.2mJ, 33.8kW peak power pulses
at 170ns is obtained. The fourth one is based on an active phasemodulated Q-switched laser, more than 100W average power and5mJ pulse energy at 5?s regime is obtained. The fiber core/cladding
diameters in the final stage amplifier of the four types of amplifiers areof 50/400µm, 50/400µm, 30/400µm, and 30/400µm, respectively. In
experiment, we coiled the fiber to an appropriate diameter and strip off
the high order mode as well as pump light to improve the beam quality.
The measured beam quality M2 in the 10ns and 100ns amplifiers areboth about 3, and the measured beam quality M2 in the ps and ?samplifiers are about 1.5. All pulse amplifiers work steadily without
any distinct nonlinear effects such as Stimulated Brillouin and Raman
scattering.

In this paper, we will discuss pulse shaping, spectral shaping
and polarization shaping techniques used in fs fiber lasers andpresent experimental results for femtosecond fiber lasers operating
at wavelengths of 1 um, 1.55 um, and 2 um, and their harmonic
generations including second harmonic generation (SHG), third
harmonic generation (THG), and fourth harmonic generation (FHG).
Aplications in biomedical imaging and diagnose will be present.

8551-16, Session 3

Properties of a double-clad erbium-doped
fiber pumped by 355-nm laser system

8551-14, Session 3

Junqing Zhao, Shuangchen Ruan, Shenzhen Univ. (China)

Yb3+-doped fiber laser operating at longwavelength

Erbium-doped fibers often pumped by 980 nm laser diodes or 1480
nm pump lasers, in order to construct high-efficiency fiber lasers or
fiber amplifiers. Besides that, five other absorption bands except
the one centered at ~490 nm, between 480 to 1500 nm, have also

Hanwei Zhang, Pu Zhou, Hu Xiao, Xiaolin Wang, Xiaojun Xu,
National Univ. of Defense Technology (China)
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High-Power Lasers and Applications VI
been investigated using corresponding pump sources. However, theabsorption bands fallen in the ultraviolet (UV) region have never been
experimentally investigated using a corresponding pump laser, up tonow, although their existences have been theoretically predicated.
We experimentally investigated, for the first time to our knowledge, thefluorescence properties of a home-made double-clad erbium-doped
silicate fiber (DC-EDF) using a 355 nm laser system as pump source.
Broad fluorescence spectra covering most visible region, from 450 to
850 nm, and part of near-infrared region, from 1400 to 1700 nm, weregenerated from the DC-EDF with different lengths and at different pump
powers. The different excited transition lines, fallen in a wide spectrum
range from visible region to near-infrared region, were analyzed mainly
based on the energy-level system of erbium ion. In our experiments,
the excited central wavelengths after 8 m DC-EDF, at the pump powerof ~860 mW, were 474.34 nm, 505.34 nm, 559.08 nm, 670.76 nm, and1555.25 nm, respectively. All the obtained central wavelengths had
different red-shifts compared to the original transitions of erbium ions.
Phenomena including spectrum red-shifts and fluorescence-line-width
broadenings, especially in the near-infrared region, occurred as the
DC-EDF lengthening, which were qualitatively analyzed. For contrast,
a piece of ~13.7 cm long highly doped single mode (SM) Liekki Er
110-4/125 EDF and an erbium-ytterbium (Er-Yb) co-doped crystal
were also exited by the same pump laser. The results showed that theexcited fluorescence spectra of DC-EDF and SM-EDF had much larger
spans than those of Er-Yb co-doped crystal, i.e. line-broadenings. A
qualitative analysis was given to indicate the possible mechanisms
behind the differences between them. This work demonstrated a newroute to pump erbium-doped fibers, as well as to get more exited
fluorescence lines; thus, it will find wide potential applications in widerwavelength-range fluorescence sources and new- wavelength-emitted
fiber lasers.

8551-17, Session 4

Design and modeling of 10-kW level singleside-pumped slab laser amplifier chain
Xing Fu, Mali Gong, Tsinghua Univ. (China)
We report a novel design of solid-state laser amplifier chain based on
Nd:YAG gain mediums, by lining up multiple single-side-pumped slabs
in an unique manner. The scheme takes advantage of the excellent
power scalability of the side-pumping configuration, and allows areduction in cost and complexity comparing to the conventional way, by
decoupling the cooling and pumping interfaces and thus avoiding watersealing application and water contamination to the crystal.
The pump system is designed with optimization, while the main focus
is the feasibility of efficient power scaling through the amplifier chain.
Specifically, influences of ASE effects on the amplifier performance(power scaling, beam quality and transverse mode profile) are describedin detail, considering the re-amplification of ASE along the slab chain.
A point design at 10 kW power level with a total extraction efficiency of
46% is presented with a well-developed numerical modeling.

8551-18, Session 4

LD-pumped 30W high beam quality 1064 nm
laser at a 500-Hz repetition rateZhen-xu Bai, Ming-Liang Long, Gang Li, Beijing Univ. ofTechnology (China)
A LD-side-pumped Nd:YAG all-solid-state two voltage supplied
Q-switched nanosecond laser was demonstrated. The laser cavity isa plane-to-plane linear cavity. Fundamental mode 1064 nm in center
wavelength with pulse width tunable from 5ns to 20ns was obtainedat the repetition rate of 500 Hz. The oscillator was scaled up to 30 W
through 3 stages Nd:YAG amplifiers at the pulse-width of 6 ns withthe divergent angle less than 3 mrad, and the single pulse energy
fluctuation was less than 1.16% in 1 hour operation.

8551-20, Session 4

Is diamond a good material for wavelength
conversion at high power?
Richard P. Mildren, Ondrej Kitzler, Aaron McKay, Hua Liu,
Macquarie Univ. (Australia)
The recent availability of high-quality and low-cost synthetic crystal
diamond has stimulated major activities in several areas of optics
including laser source development. Although the use of diamondin Raman lasers has prevailed only in the last 5 years, it has alreadyenabled the highest efficiency and output power for several of theprominent laser design configurations. With the thermal conductivity of
diamond being two-orders of magnitude higher than most other laser
host materials, and its low thermal expansion coefficient, diamondholds substantial promise for enabling Raman-functional devices
with greatly enhanced power handling capacity. The external cavity
Raman laser is a conceptually simple approach to wavelength shiftinga pump laser source, and for increasing beam brightness. Diamondexternal cavity Raman lasers have yielded the highest powers, as far
as we aware, with 25 W pulsed and 10 W cw. However, the output
power limitations of external cavity diamond Raman lasers are yet tobe elucidated. In this paper, we summarize the current state-of-theart in high average power external cavity Raman lasers in pulsed andcontinuous wave formats. We also review progress in external cavity
diamond Raman lasers operating in picosecond, nanosecond andcontinuous wave temporal regimes. By considering thermal lensing, andthermal-gradient induced stress, we investigate the design issues when
scaling output power and estimate power limits. We show the highthermal conductivity, low thermal expansion coefficient and high flexuralstrength of diamond, combine to ameliorate these three effects toenable relatively straightforward order-of-magnitude power increases.

8551-21, Session 5

The technologies on lidar range profile,
Doppler spectra, and range Doppler image
for target recognition
Mingjun Wang, Xianyang Normal Univ. (China)
The characteristics laser scattered from target with rough surface
has been an increased interesting and need for further utilizing these
theories and experiments to study the laser radar imaging technologies
for past several decades. And with the development of laser detected
technologies in aerospace and air industry, more and more many aeroand air crafts is of decisive influence on our national contravallation,intercommunion, civilian industries and other applications, foracquisition, tracking, limited discrimination, aim point selection, andperforming their different tasks. The Range Resolved Doppler Imaging(RRDI) Lidar will be a research hotspot in aerospace and national
defence fields. In this paper, we comprehensive review previous works
on Lidar RRDI of the target including the experiments, simulations
and features which are useful for target discrimination. The problemsof the Lidar imaging system are analyzed to solve in experiment andmodel. The developed achievements of Range profile, Doppler spectra
and Range Doppler imaging Lidar are reported in detail. As special
examples, the Laser range Profiles and Range Resolved Doppler
imaging features of a cone and cylinder are respectively shown. Our
works can be used for laser applications as well as target recognitionand discrimination.

8551-23, Session 5

Phase monitor in coherent beam steeringsystemDengcai Yang, Dayong Wang, Zhiyong Wang, Beijing Univ. ofTechnology (China)
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Conference 8551:
High-Power Lasers and Applications VI
Coherent beam steering system(CBSS) attract great attention for its
amazed advantages. CBSS provides an elegant means for achieving
the inertialess, high-resolution random access beam steering and manyother advantages, so it is widely studied by researchers for numerous
applications, including laser radar, laser projection displays and highpower laser process .

We put forward a quasi-concentric laser resonator configuration
employing a line-shaped end-pumping profile (QRLE).A thermal
lensing modeling of the QRLE is developed, including the quartic
phase deformation and the dependence of the thermal focal poweron the TEM00 mode size at the thermal lens.Based on the calculation,
we found that the dynamic operating point of the QRLE depends
on both the resonator condition and the thermal effect condition.
Furthermore, we predicted that the operating point in the subcriticalregion is insensitive to power fluctuation, i.e., the QRLE with extremely
short cavity length is capable of stable operation. The validity of ourprediction was well confirmed by theoretical modeling and experimental
realization.

In CBSS, One of the key technologies is the phase monitoring. After
monitoring the phase of each beam. Then the phase difference ofadjacent beam is controlled. The combination beam is steered for thevariation of the adjacent beam phase difference. So how to measure thephase different is very important in the CBSS. In this paper, A approachis provided to measure the phase difference between the adjacent two
beams. In this approach, a M-Z interferometer is used. The adjacent
two beams as the two branchs of the interferometer respectively. It
monitor the phase difference between adjacent two beams in the CBSS
through measurment the output of the interferometer. The output of
the interferometer is callculated theoretically. It is assumed p1,The
test value of the interferometer is assumed p2. The phase differenceis calculated through the theoretical(p1) and practical(p2) test value.
Even the steering of the CBSS can be calculated from the adjacent two
beams phase difference. Still we can control the beam phase throughthe closed loop circuit. In this paper, we design the M-Z interferomtor
and set up it. And still the measurment circult is designed and set up.
In this experiment, we test the output of the inerferometor above ten
hours. The output is very stable. And the variation of the output lessthan 0.04dB.

Compared to conventional resonator designs, the QRLE resonator
design produces the fundamental mode output with an LD bar insteadof the fiber-coupled pump source and realizes good stability withshort cavity length, demonstrating a clear advantage of both low costand compactness. Based on the QRLE configuration, we produced>12 W pulsed TEM00 output, with the repetition rate of 30 kHz andoptical-optical efficiency of 27%. The laser output mode is elaborately
symmetrized in two directions in terms of beam quality, waist radius,
and waist position.

8551-19, Poster Session

Modeling of distributed-side-pumped slab
lasers: power scaling by adding slab units

8551-24, Session 5

Xing Fu, Qiang Liu, Mali Gong, Tsinghua Univ. (China)

A high-power structured light vision systemused for remote fast and effective obstacle
detection of automated vehicle in off-road
environment

We present a novel distributed-side-pumped configuration for power
scaling of solid-state slab lasers, which combines the advantagesof both end-pumped and side-pumped geometries, realizing large
absorption length and large pump area at the same time. In the
distributed-side-pumped slab laser, the long gain medium can bedivided into multiple segments (slab units), each of which adopts an
end-pumped like geometry, thus the pump uniformity and the utilization
ratio of the whole slab are greatly improved comparing to the endpumped scheme. Furthermore, this configuration decouples the pumpwindows from the cooling areas, avoiding the necessity of water sealing
the optical surfaces.

Xiao Kang, Wei Zhu, Li Tian, KeJie Li, MaoSong Zhang, Jing
Jiang, Beijing Institute of Technology (China)
How to achieve remote fast and effective obstacle detection in offroad environment is a key and difficult part of the automated vehicle
navigation. As a non-contact measurement method, structured lightvision system is widely used in the industrial measurement for its highprecision, fast speed and active-controlled characteristics. In thispaper, a high-power structured light vision system, which is composedof a high-power 12W 808nm continuous point light source laser withthe divergence angle 2.4mrand, fast piezoelectric ceramics steering
mirror of PI and the high sensitivity industrial camera of DALSA with
the narrow-band filter plate of 808nm, is used for the remote fast andeffective obstacle detection in off-road environment. The light spots
emitted by the laser are projected to the steering mirror continuously
and are formed the line structured light in the ground through the fastswing of the mirror. The image of the light stripe is obtained by thecamera. When there is an obstacle, the distortion of the light stripe
in the image will occur, which is used to obtain the position and size
information of the obstacle through fast image processing. Experimentresults show that, with the high-power laser, the system can detect
the obstacle which is in front of the vehicle with the distance of 120m.
Detection time of this system can reach 10ms and detection accuracy
can reach 5cm which meet the automated vehicle remote fast andeffective obstacle detection requirement in off-road environment at the
speed of 120km/h.

The parameters of gain medium and pumping system are carefully
optimized, while numerical calculation of thermal effects for composite
slab and homogeneous slab are compared. An oscillator based the
Nd:YAG slab that includes 5 slab units, is expected to produce CW
output at 1kW level, with the optical-optical efficiency of 52.6%. By
adding more slab units, the distributed-side-pumped slab laser can beenhanced easily and efficiently.

8551-22, Poster Session

The research of adaptive optics technology
for Fourier telescopy
Changming Lu, Gao Xin, Tang Jia, Jianjun Wang, Beijing
Institute of Tracking and Telecommunication Technology (China)
Previous experiments in both the lab and field have verified that theFourier Telescopy (FT) technique to imaging geostationary targets isboth viable and robust. By theory analysis and numerical calculationof power dispersal and atmosphere’s affection, it is proved that the
Adaptive Optical (AO) System for the transmitter subsystem of FT isnecessary. A special AO system is designed for FT. The AO system
includes two wavefront sensors (WFS), a deformable mirror (DM) andan actuator command computer. The AO system can use laser guidestars, GEO itself or star as reference star. Two wavefront sensors havedifferent functions. One WFS is used to measure the wavefront of thereference star’s wavefront after it’s broadcast through the atmosphere,
the other WFS is used to measure the transmitted laser’s wavefront
before it leave the telescope. The actuator command computer syncalculate the DM’s distortion value according to two waveront sensors’

8551-6, Poster Session

Q-switched quasi-concentric laser resonatorwith line-shaped end-pumping profile:
power-insensitive operating point andsymmetrized TEM00 output
Xing Fu, Qiang Liu, Mali Gong, Tsinghua Univ. (China)
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High-Power Lasers and Applications VI
measure results and figure out the drive voltage of every actuator.
The AO system of Fourier Telescopy will realize two functions. On the
one hand, it will improve the transmitted beam’s quality, decrease thelaser ‘s size formed at the side of the GEO object and increase thecentralization of the transmitted beam. On the other hand, the AO
system will alter transmitted beam’s wavefront, make it’s value is equal
to wavefront distortion induced by atmosphere turbulence, but having
reverse direction, so the AO system will decrease the infection to theuplink beam caused by atmosphere turbulence.

8551-25, Poster Session

Study on laser ranging to medium-longrange moving target
Zhi-Chao Wu, Xiuli Zhang, Xi’an Technological Univ. (China);
Lixin Zu, Beijing Chengxin Science and Technology Ctr. (China)
In view of the high precision ranging needs of military, civilian, laser
ranging to medium-long range moving target is studied. We adopted
three high power diode arrays with symmetric distribution side pumped
Nd:YAG ceramic crystal. According to the thermal focal length of lasermaterial, we optimized the cavity structure and designed reasonablecooling system. In our experiment, the cavity dumping technology andthe pockcls effect of KD*P crystal were used for high pulse repetition
rates, short pulse durations. So, under repetition rate of 1 kHz andsingle pulse pumped energy of 144 mJ, the high peak power and theshort pulse durations are obtained, which have improved the ranging
precision to some extent. By using the time to digital conversion chip
TDC-GP2 and related circuit, the precise measurement of laser flighttime is measured. Finally, laser ranging about 5 km moving target isrealized, and the ranging precision is less than ± 2m. The results formed
the basis for the further development of the high precise and long range
moving target laser ranging.

8551-41, Poster Session

Treatment of numerical overflow insimulating error performance of free-space
optical communication
Fei Li, Anhui Institute of Optics and Fine Mechanics (China) andUniv. of Science and Technology of China (China); Zaihong Hou,
Yi Wu, Anhui Institute of Optics and Fine Mechanics (China)
Gamma-Gamma distribution model was widely used in numericalsimulations of free-space optical communication system. The
simulations were often halted by numerical overflow error due toexcessive parameters. Based on former research, two modified models
were presented utilizing scientific calculation software and program.
Factors of original model where overflow arises were transformed
into corresponding logarithmic formats adopting substitution andrecurrence, and numerical overflow in the process of calculation
was eliminated. Through numerical calculation the practicability andaccuracy of modified algorithms were proved and the advantages anddisadvantages of the two algorithms were listed. The proper algorithm
should be chose according to practical situation. The two algorithms
were also applicable to other numerical models based on gammagamma distribution such as outrage probability and mean fade time ofwireless optical communication.

8551-42, Poster Session

Parameters optimization of the beam cleanup system based on stochastic parallel
gradient descent method
Sanhong Wang, Junfeng Cui, Taiyuan Satellite Launch Ctr.

(China); Haotong Ma, Yonghui Liang, Qifeng Yu, National Univ.
of Defense Technology (China)
In a high-power laser, the system aberrations and the dynamicaberrations caused by thermal absorption degrade the beam quality.
The diffraction losses incident to these aberrations will reduce
the laser’s output power. Adaptive optics (AO) technique basedon a stochastic parallel gradient (SPGD) algorithm can be used tocompensate for the wavefront distortions in real time to clean up thelaser beam. In such a beam clean-up system, a deformable mirror iscontrolled by the SPGD algorithm to optimize a scalar beam quality
metric. According to the algorithm, statistically independent small
random perturbations are simultaneously applied to all the control
channels of the deformable mirror in each iteration step, and thestochastic approximation of the corresponding gradient component of
the beam quality metric is subsequently measured. So the convergence
speed of this algorithm is faster than that of the conventional gradientdescent algorithm. However, the parameters of the gain coefficientand the amplitude of the perturbation still need to be optimized to
improve the final convergence state and speed of the SPGD algorithm.
A simulation system of the beam clean-up based on SPGD was built
up to be used to study the optimizing and scaling method of the twoparameters. Beam clean-up experiments with the simulation systemwere conducted for a team of typical aberrations measured in a reallaser. The results show that the convergence property of the SPGD
algorithm is improved after the parameters being optimized.

8551-43, Poster Session

Numerical analysis of thermal effects in
micro-evaporator cooling module
Siqiang Fan, Peng Zhang, Yiping Liang, Teli Dai, Yu Zhang,
Chongqing Normal Univ. (China)
At present, the cooling ways of LD with high power are mainly two
types, freezing by the cooling water going through micro channel
and freezing by the gastification of liquid nitrogen. Both of them have
deficiency. The first type needs special freezing machine which can
produce cooling water .Besides, the efficiency of cooling is quite
low. The latter type needs plenty of liquide nitrogen as consumablematerials. The micro channel cooling module uses the theory of normal
cooling with single compresser and adopts Freon as its freezing
medium. Strong difference in temperature which has high efficiency ofheat dissipation will take place between the micro channel tune andthe heating surface of LD if the compressor , freezing machine andsteamer are small enough. In the paper, the temperature of LD heating
surface and steam tune is defined at 25 degree and minus 10 degree
respectively. The range of temperature of micro channel will be work out
according to the Numerical analysis of Matlab.

8551-44, Poster Session

High-power Q-switched Yb-doped doublecladding fiber laser
Zhenhua Yu, Yanrong Song, Beijing Univ. of Technology (China)
The Q-switched lasers could form optical pulses with higher pulseenergy and longer pulse-duration than mode-locked pulses andhave established their role in the application fields that do not require
ultrafast speed. Recently, single-walled carbon nanostructures haverealized a novel paradigm of the passive saturable absorbers with theadvantages of wide operating range, simple manufacturing process,and extremely high nonlinearities than the normal Q-swithchedtechnology. But most of single- walled carbon nanostructures usedin the Q-swithing or mold locking experiments were mixed with
Polymer. This kind of saturable absorbers has been suffered fromhigh nonsaturable loss and low damage threshold. Here, we present
a saturable absorber based on pure single-walled carbon nanotubes
without polymer, which was directly deposited on the core surface of

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Conference 8551:
High-Power Lasers and Applications VI
one Ytterbium-doped double-cladding fiber end by optically driven
deposition method to obtain a higher output power. A linear-cavity
was employed and a 1.5m long Ytterbium-doped double-cladding
fiber played the roles of both gain fiber and the cavity. The two fiber
ends were used as the cavity end mirrors. When a 20-W 976-nm fiber
coupled diode laser was pumped from one end of the Ytterbium-doped
double-cladding fiber, 1.3W of maximum power was obtained at the
wavelength of 1070 nm. 385 ns of pulse duration with a wide range ofpulse-repetition rate from 90KHz to 540KHz were demonstrated.

and electronic transport properties probably occurred as a fact of thedifferent oxygen partial pressure used in the PLD.

8551-45, Poster Session

Jian Li, Yanrong Song, Zhenhua Yu, Cuicui Tian, Yanlin Li,
Beijing Univ. of Technology (China); Yonggang Wang, The Hong
Kong Polytechnic Univ. (Hong Kong, China)

Properties of all-fiber supercontinuum
generation by all-normal-dispersion
dissipative soliton ytterbium fiber lasers
Li Wuyi, Jian Wu, Jintong Lin, Beijing Univ. of Posts andTelecommunications (China)
Recently, widely broadened supercontinuum (SC) generation has been
demonstrated using ultrashort pulses and photonic crystal fibers. The
SC generated with this technique is a coherent ultrawideband sourcethat emits light from the small cores of the fibers, allowing the beam tobe delivered and tightly focused. The SC is also useful for advanced
new applications, such as optical frequency combs and ultrahighresolution optical coherence tomography. We realize the flattening andextending of a low-threshold all-fiber broadband SC source basedon the use of the highly nonlinear photonic crystal fiber (HNL-PCF)
in combination with a passively mode-locked Yb-doped fiber laser.
Passively mode-locked fiber laser operating in the all-normal-dispersion(ANDi) regime with high pear power is great important to generate
ultrafast pulses near 1 micron. In this paper, we report the dissipative
soliton operation of an Yb-doped ring fiber laser without dispersion
compensation and an additional filter that is passively mode-locked by
nonlinear polarization rotation (NPR). The formation of the dissspative
soliton pulse is a self-consistent result of various effects in the laser
cavity. The spectral broadening resulting from the normal group velocity
dispersion (GVD) and nonlinear phase accumulation is balanced bygain saturation and narrowing. A 619 mW, 487 fs high-power ultrashortpulse was generated at 1060 nm in Yb-doped fiber-chirped pulse
amplification system. We show that the use of the HNL-PCF with a zero
dispersion wavelength close to the pump laser wavelength leads toefficient generation of nonlinear broadening. SC wave with the 20 dB
bandwidth of ~1200 nm has been obtained.

8551-46, Poster Session

Oxygen partial pressure influence on thecharacter of InGaZnO thin films grown by
PLD
Lu Yi, Li Wang, Jiangbo Chen, Yulin Gan, Beijing Univ. ofTechnology (China)
Amorphous oxide semiconductors (AOSs) are promising for emerging
large-area optoelectronic applications because of capability of largearea, uniform deposition at low temperatures such as room temperature(RT). Indium-gallium-zinc oxide (InGaZnO) thin film is a promising
amorphous semiconductors material in thin film transistors (TFT)
for its excellent electrical properties. In our work, the InGaZnO thinfilms are fabricated on the SiO2 glass using pulsed laser deposition(PLD) in the oxygen partial pressure altered from 1 to 10 Pa at room
temperature (RT). The targets which were prepared by mixing Ga2O3,
In2O3, and ZnO powder at a mol ratio of 1: 7: 2 before the solid-state
reactions in a tube furnace at the atmospheric pressure. The targets
were irradiated by an Nd:YAG laser(355nm).Finally, we have three filmsof 270nm, 230nm, 190nm thick for 1Pa, 5Pa, 10Pa oxygen partialpressure. The product thin films were characterized by X-ray diffraction(XRD), atomic force microscopy (AFM), Hall-effect investigation. The
comparative study demonstrated the character changes of the structure

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8551-47, Poster Session

Passive Q-switched Nd:YCOB laser with asingle-walled carbon nanotube saturable
absorberA passively Q-switched Nd:YCOB (Nd3+:YCa4O(BO3)3) laser wasdemonstrated at the wavelength of 1055 nm employing a single-walledcarbon nanotube saturable absorber (SWCNT-SA).Nd:YCOB crystal wasgrown by the Czochralski method, and its structure was measured byusing a four circle X-ray diffractometer. The transparent spectrum from
200 to 2600 nm was measured at room temperature. The fluorescence
spectrum near 1.06 um showed that the main emission wavelength of
Nd:YCOB crystal was centered at 1060.8nm. SWCNT-SAs exhibit not
only high nonlinear optical effect comparable to that of SESAMs but
also low nonsaturable loss and high damage threshold. Moreover, byconfigure different concentrations of SWCNT-SA solution, we could
dropped the liquid on different types of mirror to produce different typesof absorber mirrors. We put 10mg of SWCNT powder into 10ml sodium
dodecyl sulfate (SDS) aqueous solution. Then the SWCNT aqueous
solution was ultrasonically agitated and centrifuged 10000r/min for 10
minutes. After that, the SWCNT dispersion was diluted and poured
onto a glass substrate to evaporated at atmosphere or in oven. Using asingle-walled carbon nanotube as saturable absorber (SWCNT-SA) ( wedropped SWCNT-SA fluid on the reflect mirror), a passively Q-switched
Nd:YCOB (Nd3+:YCa4O(BO3)3) laser was realized at 1055nm pumped
by a 808 nm diode laser. A 242 mW output power were obtained at thepump power of 9W in a plano-concave cavity. The slope efficiency is27%, the repetition rate is 22.7kHz.The duration is 2µs and the energy
could reach 10.7µJ.

8551-48, Poster Session

The fabrication, optical properties research,
and application in the Q-switched Yb doped
double cladding fiber laser of single-walledcarbon nanotubes
Cuicui Tian, Yanrong Song, Zhenhua Yu, Jian Li, Yanlin Li,
Beijing Univ. of Technology (China); Yonggang Wang, The Hong
Kong Polytechnic Univ. (Hong Kong, China)
The single-walled carbon nanotubes can be used as saturable
absorber in Q-Switched and mode-locked lasers recently.The different
concentration and different ultrasound time of dispersed single-walledcarbon nanotubes could get different parameters of the absorber andthen could influence the characteristics of the pulsed laser. The opticalinfrared absorption spectrum of all different kinds of single-walledcarbon nanotubes have been measured respectively. The influenceof the concentration and ultrasound time on the single-walled carbon
nanotubes’ absorption rate were discussed. Along with the increasingof the concentration and ultrasound time the single-walled carbon
nanotubes’absorption rate increases proportionately. The structure andmorphology of the single-walled carbon nanotubes were investigatedby the atomic force microscope (AFM) and scanning electron
microscopy (SEM) respectively. Atomic Force Microscope exhibited thesingle-walled carbon nanotubes’ strip shape microstructure of different
sizes. As we can see in the photographs the single-walled carbon
nanotubes’ diameters are from about a few tenths of nm to a few nms
unequally. There was more obvious aggregation of SWCNTs at thehigher concentration under the scanning electron microscopy. We use
the single-walled carbon nanotubes saturable absorber (SWCNTs) in the

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Yb doped Q-switched double cladding fiber laser, a duration of 650ns
pulses were obtained at the center wavelength of 1037 nm, the average
output power of 1.3w with the pump power of about 10w.

8551-49, Poster Session

Temperature distribution of laser crystal in
LD end-pumped Nd:YAG/LBO blue laser
Lei Zhang, Shijiazhuang Univ. of Economics (China)
It is well known that diode-pumped solid-state laser have provided
many excellent advantages such as smaller cubage, stable power
and longer using-life. Still, it is more difficult to obtain higher stable
output power because of the strong thermal effects caused by the heat
deposited in laser crystals. The thermal distribution is determined by
the pumping light distribution. With the high power pumped, the heatcaused by radiationless transition and absorb through the laser crystal
influences the optical behaviour of the laser crystal which makes theresonator unstable, and greatly limits the maximum pump power. There
are three aspects caused the thermal effect of laser crystal: refractive
index variety, end-face distortion and double-refraction stress of laser
crystal. The threshold value and output power are seriously influenced
by the distribute radius and total departure of pumping light, so thetemperature distribution of laser crystal is one of the most importantfactors which influence the quality of output light.
In this study, LD End-pumped Nd:YAG/LBO solid state Blue Laser isrealized by even hollow cavity. The temperature distribution in different
cooling system was studied. A thermal distribution model of Nd:YAG/
LBO crystal was established. Based on the calculation, the temperature
distribution and deformation of laser crystal in different cooling systemwere obtained. The results show that the temperature decreases fromthe pump end to the launch end exponentially. When the pumping
power is 2 W and the radius of pumping beams is 320µm, a biggest
output power 46.3 mW of blue light is achieved, giving an frequency
doubled optical conversion efficiency of 2.3%. The temperature
distribution and end face distortion of the laser crystal are lowest byusing side directly hydrocooling method. The study shows that, the side
directly hydrocooling method is a more efficient method to control the
crystal temperature distribution and reduce the thermal effect.

8551-50, Poster Session

Evolution of damage morphology in InSb
irradiated with ultrashort laser pulses
Amit Garg, Acharya Narendra Dev College (India); Surendra K.
Bansal, Univ. of Delhi (India)
We report here the evolution of laser damage morphology in polished
InSb as a function of increasing energy and number of pulses using
ultrashort laser pulses. The laser pulses used in the present studies
are of 50 femtosecond duration having a repetition rate of 10 Hz witha central wavelength around 800 nm. Damage primarily occurs in theform of surface removal with no crater formation. The morphology
shows periodic structuring in the form of ripples and grains. Microcrater
formation is observed only at a very high fluence. The results are
discussed in light of various ablation theories.

8551-51, Poster Session

Numerical analysis of beam quality’s
influence on coherent combination ofmultiple laser beams
Yi Tan, Xinyang Li, Institute of Optics and Electronics (China)
A numerical simulation model for coherent combination of multiple
rectangular beams, square beams and circle beams has beendeveloped. The factor b of single beam which was with wavefront
aberration of Zernike polynomials from two to twenty-one and its
combination was obtained by numerical calculation through fast
Fourier transform (FFT). The influence of piston on coherent beamcombination was analyzed when each beam has wavefront aberrationof Zernike polynomials from two to twenty-one. We demonstrated
that the influence of piston was small if other aberrations were high.
The relationship between the average of single beam’s factor b andfactor b of its coherent combination was also obtained by numericalcalculation. A fitting formula was used to fit the discrete number. By thisway, an expression of the relationship was acquired. Fitting coefficients
between numerical calculation and theoretical result were comparedand the affecting factor of the difference was analyzed. We concluded
that fitting coefficients of numerical calculation result was smaller thantheoretical result because of beam’s arrangement and filling ratio.

8551-52, Poster Session

Effect of a self-injected electron bunch on
the laser wakefield and electron accelerationin the bubble regime of the laser-plasmainteraction
Ming-Ping Liu, Nanchang Univ. (China)
The effect of a self-injected electron bunch from background plasmaon the laser wakefield and electron acceleration in the bubble regimeof the laser-plasma interaction is investigated by theoretical analysis.
The test electron bunch weakens the space-charge electric field of thelaser wake. The wakefield structure is strongly modified and the bubble
elongates as the density of the self-injected electron bunch increases.
The subsequent plasma electrons can be self-injected into the evolving
bubble with higher initial longitudinal momentum. As a comparison we
perform particle-in-cell simulations and it is found that the results fromtheoretical model are consistent with simulation results.

8551-53, Poster Session

Narrow linewidth, wavelength stable Er/Yb
co-doped fiber MOPA source operating at
1547.8nm
Hongxin Su, Xiaoming Li, Fuyun Jiao, Lijing Xu, Xu Li, Hebei
Univ. (China)
High-power optical sources with narrow linewidth and stablewavelength are of great importance in a wide range of applications.
Owning to the potential of high efficiency and high power level
operating in the eye-safe wavelength region around 1.55 µm, Er3+/
Yb3+ co-doped fiber lasers (EYFLs) have attracted much attention inrecent years. Though DBR configuration which uses fiber Bragg grating(FBG) as the reflector to form resonator has been widely used in EYFLs
for the sake of compactness and wavelength stability, FBGs are notvery effective for wavelength selection in high power and multimodefiber lasers, because the wavelength for the reflectivity peak varies
with the effective refractive index of the mode and the temperature in
the fiber core due to heat accumulation. In this paper, we demonstrate
the output characteristics of an optical soucre based on Er3+/Yb3+
co-doped double-clad fiber (EYDCF) in a master oscillator-power
amplifier configuration. In the experimental setup, a DFB diode laser
with linewidth less than 0.02nm and power up to 10 mW serves as themaster oscillator. The amplifier is composed of a 10m long EYDCF,
two isolators at both input and output terminals, and a 975nm pump
diode connecting with the EYDCF via a side-pump fiber coupler. A
maximum output power of 1.16W is obtained in a backward-pumping
configuration. The gain of the fiber amplifiers is up to 30.7dB. The
wavelength centered at 1547.8nm with a spectral width no more than
0.02nm shows long-time stability.

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Conference 8551:
High-Power Lasers and Applications VI

8551-55, Poster Session

8551-58, Poster Session

Diode-pumped composite YVO4/Nd:YVO4/
YVO4 mode-locked laser with ring resonator

Nano-gold colloids prepared by microwave
synthesis method and its SERS activity

Guoxi Huang, Shenzhen Univ. (China)

Lan Wang, Fujian Normal Univ. (China)

Some investigates fast physical phenomena, but the nanosecond pulse
duration of Q-switched lasers is often not sufficient. Such investigations
require mode-locked picosecond laser sources. Since the firstobservation of the self-mode-locking phenomenon in a Ti:sapphire laser
much attention has been given to both experimental and theoreticalinvestigations of self-mode-locked lasers. And the same phenomenon
was observed in the Nd:YVO4 laser, which can obtain a mode-locked
picosecond laser. It is expected that the output pulse width of modelocked laser could be more narrow when inset a saturable absorber into
the ring resonator, such as Semiconductor Saturable Absorber Mirror(SESAM). The self-mode-locking mechanism is now attributed to theoptical Kerr effect inside the Ti:sapphire crystal; thus the mechanism istermed Kerr-lens mode locking (KLM). However, the presence of spatial
hole burning in standing-wave resonators limits the efficiency andfrequency characteristics of the lasers. As ring lasers sustain oscillationof travelling-wave rather than standing wave, they can eliminate spatial
hole burning in the gain medium and enable the lasers to work in theless longitudinal modes. The less longitudinal modes could weaken
the mode-locking, but the long length ring resonator can increase thenumber of longitudinal modes. Compared with the standing-wave
resonators mode-locked laser, the ring laser has the smaller gain
dispersion, which could be easier to obtain the narrower mode-locked
pulse width. With rapidly development of laser diode pump technology,
there are many advantages of diode pumped solid state lasers, suchcompact structure, high efficiency and long service life. They makemode-locked laser technology more practical.

A novel method for rapidly synthesized Au colloidal under microwave
irradiation was present in this paper. Size of the Au nanoparticles
varied from 30 nm to 60 nm along with varying mol fractions bychloroauric acid solution reduced with sodium citrate. The prepared Au
nanoparticles were characterized by transmission electron microscope(TEM) and ultraviolet-visible (UV-Vis) spectrophotometer. It is foundthat the nanoparticle size and shape are highly dependent on thereaction time and the molar ratios of the reducing agent. By the SERS
measurements of R6G, 4-MBA and BSA, this Ag colloid is shown to be
an excellent SERS substrate with good stability and biocompatibility.
As the fabrication process of this SERS substrate is simple andinexpensive, this method may be used in large-scale preparation ofsubstrates that can serve as an ideal SERS substrate in biomedical
application.

8551-59, Poster Session

STK and application in simulation of thespace laser communication network
Jianing Wang, Jingyi He, Yue Yang, Changchun Univ. of Scienceand Technology (China)

8551-57, Poster Session

Laser communication with its large capacity communication, strong
confidentiality, structure of light and other advantages is becoming
research focus. Space laser communications networking technology
is communications network of bi-directional, multi-directional network,
which is made of satellites, ground station, near the space vehicle andso on. This paper uses the STK (Satellite Tool Kit) on a visibility analysisof the laser communication in satellite network between different orbits. Simulation results demonstrate the two-dimensional or threedimensional chart.

Effects of passivation of nitrogen plasma on
photoluminescence of GaAs substrates

8551-60, Poster Session

Yunhua Wang, Lu Zhou, Xin Gao, Baoxue Bo, Changchun Univ.
of Science and Technology (China)

Characteristic research of the waveguide bynanosecond laser pulses on LiNbO3

GaAs is one of the most important compound semiconductor materials
as substrates for 940nm semiconductor lasers, which has a wide directenergy band gap, high electron and hole mobility, and high saturation
drift velocity, etc. The band gap of GaAs is 1.424 eV, corresponding
to an emission wavelength of 940nm with high radiation efficiency.
However, GaAs is a binary compound semiconductor materials, surface
state with high density usually exists at the oxygen-exposed surface
and acts as non-radiative recombination centers resulting in rigid
pinning of the Fermi level, which has a negative effect on the lifetimeand reliability of the lasers. So, in order to eliminate the undesirable
effect of the surface state on 940nm semiconductor lasers, in thispaper, the GaAs substrate samples were treated by Nitrogen plasma
at different plasma cleaning process simulating the laser facet, andthen to deposit a SiO2 passivation layer by radio frequency magnetron
sputtering to avoid reoxidation or recontamination of the surface. We
introduced N plasma by gas glow discharge, and the fluorescence
properties of GaAs substrates were analyzed using RPM2000 rapid
photoluminescence mapper. The results showed that the sample wastreated under the conditions of sputtering power 10W, N2 flow 25sccm,
cleaning time 15min, the luminous intensity was increased by 63.61%
compared with before passivating. The optimized result illustrates
that the plasma cleaning process can help to effectively remove theattached contaminants and the native oxides.

Zigang Zhou, Southwest Univ. of Science and Technology(China)In this paper, we report unidirectional ring resonators composite YVO4/
Nd:YVO4/YVO4 mode-locked laser. We present the results of ourresearch on the mode-locked ring laser. By optimizing the resonator, amode-locked picosecond ring laser at 1.06 µm was achieved.

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The damage threshold and morphology of optical material have been
investigated by 800nm, 76MHz, 30fs laser pulses, in 50 magnificationand 0.65 numerical aperture (NA) objective in the Z-LiNbO3 crystals.
The influence of several experimental parameters, for example energy
per pulse, a ser scanning speed, or repeat time on writing quality
and the characters of relative microstructures has been analyzed andstudied in theory. The damage structural change, from small refractive
index changes to micro explosion structure in LiNbO3 induced byhigh intensity nanosecond laser is studied. Nonlinear interactions of
nanosecond laser and transparent material are discussed.
The subsurface morphology of the processed structures inside the
LiNbO3 was obtained by a Nikon optical microscope. Particularly, we
find that the wider width of the buried channel with the increase ofenergy per pluse, repeat time and the reduce of scanning speed. It wascaused by the avalanche ionization and multi-photon absorption oflithium on the processed area, and which is also lead to the refractive
index change rang by the writing conditions. The result shows thatthe propagation of optical waveguide could achieve ideal effect whenthe energy per pluse is under 300mW, the scanning speed is from0.05mm/s to 0.2mm/s, and the focus depth is from 350?m to 400?m.
At last, in this approach, the insertion loss of 1?4 optical splitter is lessthan 1dB/cm.

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8551-62, Poster Session

An equivalent method to analyze theelectrical effect induced by laser plasma
Yunjing Ji, Chunyong Wang, Bao-Min Bian, Nanjing Univ. of
Science and Technology (China)
Electrical effect induced by laser plasma in air is measured using atiny probe placed in close to a metal target. Analysis shows that theresulting signal wave varies with detection distance. Based on thetesting system, an equivalent circuit model was proposed to analyze
the formation mechanism and evolution of the electrical signal and its
dependence on the probe distance. The observed signal peak polarity
overturn was also analyzed and explained. Finally, our method provides
an explanation for the effects of the testing angle on the probe signals
according to the time and space evolution of the laser plasma.

8551-26, Session 6

Mode-locking characteristics of all-solidstate mode-locked laser with graphenesaturable absorber
Jieyu Wang, Li Wang, Beijing Univ. of Technology (China)
Ultrafast laser sources have always been an attractive field in laser
research and are acquired mostly from the mode-locked lasers by
SESAM currently. However, the fabrication of SESAM is very complex
and costly, and the saturable absorption band is limited. Graphene isa promising saturable absorber for broadband saturable absorption
due to the gapless linear dispersion of Dirac electrons. Thus it is widely
investigated in experiments in recent years. Nevertheless, there are few
theoretical research about the saturable absorption of graphene thatshould be important for designing the scheme of the experiments.
In this paper, the saturable absorption of graphene is studied bynumerical method. By using the experiment data and assuming thecharacteristics of monolayer graphene are uniform, the parametersof saturable absorption, such as saturable fluence and saturable
absorption coefficient, i.e., modulation depth, are derived from a
simple two-level saturable absorber model. With these data, basedon theoretical mode of suppressing Q-switched mode locking andcombining with all-solid-state Yb:YAG laser, the critical pump powerof suppressing Q-switched mode locking is studied. It can be seenthat saturable fluence and modulation depth increase with the numberof layers. The critical pump power will decease when the number oflayers, transmittance of the output mirror and beam waist on graphenedecrease, while cavity length increase, and it contribute to suppress
Q-switched mode locking. The minimum critical pump power will beobtain if the crystal length is 1.9mm and beam waist on gain medium
is about 67µm. Compare with SESAM, graphene is a better choice togenerate stable mode-locked laser.

8551-27, Session 6

Nonlinear graphene photonics: saturable
absorption for ultra-fast laser photonics andlarge Kerr nonlinearity for graphene based
Kerr photonics
Han Zhang, Hunan Univ. (China)
Graphene as an ideal two-dimensional form of carbon shows wonderfulnonlinear photonics property. By performing the open and close
aperture Z-scan technique, we are able to ambiguously identify thesaturable absorption and Kerr nonlinearity effect for the first time, whichcorresponds to the imaginary and real part of the third order opticalnonlinearity in graphene. Owing to its linear energy band structure,graphene exhibits broadband saturable absorption with attractive

laser photonics applications. Herein, we review the state of the art inthis rising field: graphene passively mode locked/Q-switched fiber orsolid state lasers from near infrared, telecommunication to mid infrared
wavelength band. Very recently, we experimentally confirmed thelarge Kerr nonlinearity in graphene, which indicates several interesting
Kerr based photonics applications including: self and cross phasemodulation, optical Kerr switcher, four wave mixing generation, Kerr
soliton, and so on. Both the saturable absorption and large Kerr
nonlinearity in graphene renders it as an attractive nonlinear optics
material platform, with either fundamental or application importance.

8551-28, Session 6

Experimental and simulation research of
passive mode-locking fiber laser based ona single-walled carbon nanotube saturable
absorber
Pan Zhu, Mei Sang, Ke Liu, Xiaolong Wang, Tianxin Yang,
Tianjin Univ. (China)
Single-walled carbon nanotubes has been widely used in the researchof passive mode-locking fiber laser, researchers often observed theexisting of soliton pulses in the experiment of mode-locking laser.
However, few people studied the process how mode-locking pulses
evolve into soliton pulses, while they are propagating in the laser cavity.
Here, we report a passive mode-locking laser based on single-walledcarbon nanotubes saturable absorber experimentally and a numericalsimulation based on a modified non-linear Schrodinger equation, which
is used to analyze the procedure of soliton pulse evolution in the fiber
laser. The physics of passive mode-locked fiber lasers comprises acomplex interaction of gain, dispersion and nonlinear effects. In theexperiment of mode-locking laser based on single-walled carbon
nanotubes saturable absorber, which approaches the working regimeof dispersion managed soliton lasers, we obtained 1.2ps mode-locking
pulses sequence successfully, whose repetition rate is 8.366 MHz, andthe Center wavelength of the spectrum with obvious Kelly sideband is1562.3nm. The existence of solutions in a dissipative nonlinear cavity
comprising a periodic combination of two distinct nonlinear waves
is likely to be applicable to various other nonlinear systems. In thesimulation, we find that the mode-locked pulse propagates self-similarlyin the gain fiber with normal dispersion, soon afterwards for very small
anomalous-dispersion segment lengths it approaches dissipative
soliton lasers, then gradually transforms into a regular soliton in the restof the cavity, where the dispersion is anomalous.

8551-30, Session 6

Coherent beam combination of seven highpower fiber amplifers with an all-opticalfeedback loop
Houkang Liu, Bing He, Jun Zhou, Chi Liu, Liyun Hao, Shoujun
Dai, Yunrong Qi, Xiaolong Chen, Shanghai Institute of Optics
and Fine Mechanics (China)
We demonstrated a coherent beam combination of seven high power
all-fiber polarization-maintaining amplifiers channels with an all-opticalfeedback loop. Every single channel has four stages amplifiers and theoutput power of a main amplifier reached about 50 W with an opticalto-optical conversion efficiency of 80%. A broadband laser diode witha central wavelength of 1064nm is used as seed for seven amplifiers
channels before the feedback loop been established. Spectrums of
output beams are detected before and after phase locking. Thanks
to self-organization properties of the all-optical feedback loop, many
low loss longitudinal modes are successfully selected for phaselocking when the system is in closed loop. There are no stimulated
Brillouin scattering, which is a main limitation of power scaling in active
coherent beam combination, and other detrimental nonlinear effects.

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Conference 8551:
High-Power Lasers and Applications VI
Seven output beams of main amplifiers are space coupled via sevencollimators and carefully arranged in a hexagonal laser array in thenear field by using a homemade mirrors array module. The space duty
ratio is up to 65%, which is helpful to improve power of central lobe in
beam combination. Once the all-optical feedback loop is established,
the phase of seven fiber amplifiers is locked steadily in a very shorttime. The pleasing visibility of interference patterns in the far field ismore than 90%. The total combined power is 352 W. Undoubtedly, theall-optic feedback loop technique has the potential to boost passive
coherent beam combination to higher power and larger number ofamplified channels with low cost, compact configuration, and simple
phase-locking mechanism.

8551-31, Session 6

Phase and spectrum control requirements ofhigh intensity laser beam combining
Yanqi Gao, Shanghai Institute of Laser Plasma (China)
Because of the limited optical element aperture, damage threshold, gain
bandwidth, and so on, the output capability of a single laser beam islimited seriously. The coherent laser beam combine offers an excellent
method to improve the peak intensity which could be gotten greatly.
Aiming at getting the general requirements of the coherent beamcombine for large aperture laser facilities, this work devotes to modelingthe influences of the phase factors and spectrum factors on the
combine results. The effects of the phase factors, including the beam
configuration, piston error, and tip/tilt error, are studied analytically andnumerically. It is found that the expressions of the intensity in the focal
plane can be written as three parts, the scale factor, a point spreadfunction (PSF), and a grid function (GF), for the ideal beam combine
and beam combine with piston error. Every part has its special physicalmeaning, and decides different characteristics of the combined focus.
For the beam combine with tip/tilt error, though the expression of focal
spot intensity can not be separated like the above situations, every
part still has obvious physical meanings. The results show that thebeam configuration can not affect the Strehl ratio of the combined
beam, but it influences the FWHM of the main peak and the ratio of
the main peak and the side peak. The piston error affects the gridfunction greatly, including its maximum value, transverse translation,and shape. For the two beam combine, a piston error less than 2π/5
rad is suitable. For multi-beam combine, the standard deviation of thepiston error should be no more than 2π/10 rad. The tip/tilt error affects
the superposition degree of the focal spots of the combined elements
directly. A requirement of 0.5~1?rad for the standard deviation of the
tip/tilt error is adequate. The effects of the spectrum factors, including
the longitudinal chromatism, high order dispersion, and residual chirp,
are studied analytically and numerically. Results show that the above
spectrum factors have significant influences on the short pulse coherent
beam combine, and must be controlled carefully when the pulse isshorter than 1ps.

8551-32, Session 7

Fiber coupled high-power multi-mode diodepump lasers
Tao Wang, Oclaro Technology (Shenzhen) Co., Ltd (China)
This paper summarizes complete fiber coupled diode pump laser
products and solutions mainly used in fiber laser application, while
covering both Yb and Tm systems. The combination of various power
ratings, wavelength ranges and packaging platforms on single/
multi emitters, and mini-bars offer flexible options to customers byenabling flexibility of emitter or bar fiber coupling solutions during thesystem design. Some of key features of pump diodes will be normallyconsidered like brightness, driving current, pumping efficiency, system
cooling requirements, diode protection, reliability, and cost. Advanced
packaging technologies on diverse platforms assure the most costeffective, high coupling and reliable solutions to the customers.

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Oclaro’s high power diode laser products are built with the same
manufacturing standard, and some even share a common platform, as
telecom products which enable high power diode laser high reliability
and stringent qualification requirements for industrial customers. The
low cost packaging solution also offers customers an attractive $/W
margin for pump diodes which is the most critical and cost consuming
component in the fiber laser system. Single emitter, multi emitters andmini-bar fiber coupled platforms are fully developed internally andmature for mass volume manufacturing with these advanced packaging
technologies.These factors lead to more explosive growth in the fiber
lasers market share.

8551-33, Session 7

A ridge waveguide quantum well AlGaAs/
GaAs laser design
Marziyeh Nazari, Islamic Azad Univ. (Iran, Islamic Republic of);
Mohammad Mahdi Oskoie Tabrizi, Sharif Univ. of Technology(Iran, Islamic Republic of)
An advanced structure of AlGaAs laser diodes has been designed using
the simulation software.
Simulation results suggest that the thicknesses of SCH layers, inner
cladding and outer cladding layers should be changed in order to give
low loss, narrow far-field divergence angle and high confinement factor.
The Thickness of the etch stop layer is optimized to give the required
effective lateral refractive index. At the end the channel width and ridge
width are also optimized to obtain single lateral mode.
The aim of our study was three folds: (1) to provide the comprehensive
analysis and calculations to design a ridge waveguide laser. In thesimulations, the thicknesses of SCH layers, inner cladding layers
and outer cladding layers are varied in order to observe variations of
far-field divergence and the total confinement factor as functions oflayer thicknesses. Comparison among loss, narrow far-field divergenceand high confinement factor are made to optimize layer thicknesses,(2) The thickness of an etch stop layer is optimized to achieve therequired lateral effective refractive index difference, and also the far-field
divergence of the ridge waveguide laser, (3) the channel width and ridge
width are designed to maintain single lateral mode and low loss byusing the three layer dielectric slab waveguide calculations.

8551-35, Session 7

Linewidth-tunable laser diode with double
volume Bragg gratings for rubidium laser
pumpingZhiyong Li, Institute of Electronics (China) and Graduate Univ. ofChinese Academy of Sciences (China); Rongqing Tan, Instituteof Electronics (China); Cheng Xu, Lin Li, Wei Huang, Institute ofElectronics (China) and Graduate Univ. of Chinese Academy of
Sciences (China)
In the research field of diode pumped alkali laser (DPAL), one of thecritical issues is matching the linewidth and central wavelength of thepumping diode laser with that of the alkali vapor’s absorption line. Dueto the radial temperature gradient in the active medium of high power
alkali laser system, the diodes with ultra-narrow linewidth may notpump efficiently than diodes with wider linewidth. With double volume
Bragg gratings (VBG), we achieved a laser diode (LD) with linewidth
tunable while the output power changed no more than 1% during theadjustment. The temperature of the VBGs was controlled by thermoelectronically coolers respectively. Because VBG’s central wavelength
shifts with temperature while the bandwidth maintains the same,
adjusting the temperature differences between the two VBGs resulted
in different bandwidth of the feedback to the LD. As a result, linewidthof the LD with double VBGs can be tunable in a large range. Throughcontrolling the temperature differences, the linewidth of the LD, which

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High-Power Lasers and Applications VI
was 1.8 nm before adding the two VBGs, was tunable from 90 pm to
200 pm while the output power changed little. By changing the VBGs’
temperature simultaneously, central wavelength of the linewidth-tunable
LD was tunable from 779.40 nm to 780.10 nm. Since the tunable range
covered the Rb D2 absorption line, the LD will help to choose thepumping source for high-power alkali vapor laser system.

8551-36, Session 8

High-average-power eye-safe diamond
Raman laser
Aaron M. McKay, Ondrej Kitzler, Hua Liu, David Fell, Richard P.
Mildren, Macquarie Univ. (Australia)
Diamond is a highly attractive laser material due to its exceptional
material properties, which in most cases, outclasses competing
materials. Its high thermal conductivity, low thermal expansion and wide
transparency make CVD-grown diamond especially commendable forhigh-average power laser applications. Already diamond, in comparison
to more mature Raman crystalline materials, has demonstrated thehighest recorded output powers for both pulse and continuous wave
operation. In addition, when combined with well-established Nd laser
technology, the 1332 cm-1 Raman frequency in diamond provides aconvenient and efficient route to the eye-safe spectral region via its
second Stokes shift. In this paper, we report an external cavity Raman
laser using a 10-mm-long low-loss CVD diamond pumped by a 35
W q-switched side-pump Nd:YVO4 laser with approximately 22 ns
pulses at 36 kHz pulse repetition frequency. Our diamond Raman laser,lasing near 1485 nm, had in excess of 10 W and efficiencies greaterthan 50%. This represents a substantial improvement in power whencompared to other crystalline Raman lasers operating in this eye-safe
region. The thermal lens strength was estimated for an external cavity
diamond Raman laser which were also compared to those using KGWwith similar pumping and resonator conditions. This direct comparison
between KGW and diamond in similar resonators gives insight topotential thermal design issues when scaling to higher Raman output
powers and estimates possible power limitations.

8551-37, Session 8

Solar pumped laser with the grooved Nd:
YAG
Dan Fang, Changchun Univ. of Science and Technology (China)
As the global climate is warming, the earth environment is deteriorated
gradually. It is desired to exploit renewable energy and clean energy.The
ultimate renewable energy source might be the solar energy, which isfar from fully utilized. The power density of solar on earth is so low thatit can’t achieve to pump laser. To surpass the lasing threshold, the solar
has to be highly concentrated. A Fresnel lens as primary concentrator
instead of the large-dimensional paraboloidal mirrors collects the solar
radiation in 1m2 efficient areas. Sunlight concentrated is coupled
into the conical chamber pumping grooved Nd: YAG laser media?in
8mm-diameter and 100mm-length. The pumping cavity is designed to
combine end-pumping to side-pumping, in which the pumping lightcomes from many directions, which could compensate the drawbacksof single end-pumping or side-pumping. The cooling effect is improvedon grooved crystal rod, which changes the state of the fluid motion into
turbulence. By comparing grooved rod to ordinary rod, the output laser
power and beam quality is by 25%. In our experiment, laser output of
25 W has been achieved and the collect efficiency is 25 W/m2 with thegrooved laser rod.

8551-39, Session 8

LD dual-end-pumped CW Tm:YLF laser
Xinyu Chen, Changchun Univ. of Science and Technology(China)Continuous wave Tm:YLF laser by 792nm LD dual-end-pumped ispresented. Based on the rate equation of quasi three level, we analyzed
the pump threshold and the slope efficiency of the laser system. At
the same time, according to ABCD Matrix theory, we analyzed thestability condition and the pattern matching of the plano concave
resonator. We contrast the pump threshold, the slope efficiency andoptical conversion efficiency when different output mirror transmittanceof 15% and 23% is applied. The pump threshold is lower of the 15%transmittance output mirror than that of the 23% transmittance output
mirror, while the slope efficiency of the 23% transmittance output
mirror is a little higher than that of the 15% transmittance output mirror.
Besides, the lser Beam quality are measured using output mirrors
with different radius of curvature of 150mm,200mm and 300mm when
we apply different output mirror transmittance of 15% and 23%,
respectively. For all the experiments, the Tm:YLF laser crystal keeps
18? and the temperature control method is water cooling. When weapplied L shape plano concave resonator, the length of the resonatoris 135mm, the radius of curvature output mirror is 300mm and thetemperature of the Tm:YLF laser crystal is 18?, we observed the central
laser wavelength is 1908. The threshold power is 6.8W. The highest
output power reaches 21.6 W when the totally input pump power is
53.9W. And the optical conversion efficiency and the slope efficiency is
48.1% and 40.0%, respectively. The experimental results are coincidewith the theory.

8551-40, Session 8

High-power single-frequency Nd:YVO4 green
laser by self-compensation of astigmatism
Yaohui Zheng, Shanxi Univ. (China)
High-power single-frequency solid-state green lasers can be used for avariety of roles, such as pumping of Ti:sapphire or dye lasers, precision
measurement, and high-resolution laser spectroscopy. However, thepower scaling and beam quality are limited by thermal effect of the gain
medium.
In order to quantify the influence of the thermal effect and to find an
optimal resonator scheme, the value of the thermal focus in Nd:YVO4
crystal is measured by using a probe beam technique. The measuring
results show that a strong astigmatism of the thermal lens of Nd:YVO4.
With a laser diode of the wavelength of 888nm as the pump source,
the thermal effect in the pumping progress is mitigated greatly. By
orienting the c-axis of the Nd:YVO4 crystal in the tangential plane of
the ring cavity, the astigmatisms introduced by the thermal lens andthe ring cavity can be mutual-compensated. Due to the mitigation andcompensation of the thermal effect, scaling the single-frequency laser
to higher output power, whilst retaining the excellent performance. We
obtain a high power intracavity frequency-doubling single-frequency
green laser, with maximum output power of 25.3 W, with 32.2% of
the optical-optical conversion efficiency with respect to absorbed
pump power. To the best of our knowledge, this is the highest output
power and conversion efficiency of single-frequency Nd:YVO4 laser byintracavity frequency–doubling. The power stability of the green laser at
25.3 W is better than ±0.4% for 8 h.

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Conference 8552:
Semiconductor Lasers and Applications V
Monday - Tuesday 5 –6 November 2012
Part of Proceedings of SPIE Vol. 8552 Semiconductor Lasers and Applications V

8552-1,

Quantum dot lasers and relevant
nanoheterostructures
Alexey E Zhukov, Natalia V. Kryzhanovskaya, Artem V. Savelyev,
Alexey M. Nadtochiy, Ekaterina M. Arakcheeva, Fedor I.
Zubov, Vladimir V. Korenev, Saint-Petersburg Academic Univ.
(Russian Federation); Mikhail V. Maximov, Yuri M. Shernyakov,
Marina M. Kulagina, Ilia A Slovinskiy, Ioffe Physical-TechnicalInstitute (Russian Federation); Daniil A Livshits, Innolume GmbH
(Germany); Alexandros Kapsalis, Charis Mesaritakis, Dimitris
Syvridis, University of Athens (Greece); Alexander Mintairov,
University of Notre Dame (United States)
Microring and microdisk structures (d = 3-6 ?m) comprising 1.3 ?m
InAs/InGaAs quantum dots have been fabricated and studied by
micro-PL and NSOM. Ground-state lasing was achieved well above
root temperature (up to 380 K). Effect of inner diameter on thresholdcharacteristics was evaluated. Spectral and power characteristics of
QD stripe lasers operating in two-state lasing regime have been studied
in a wide range of operation conditions. It was demonstrated thatneither self-heating nor increase of the homogeneous broadening are
responsible for quenching of the ground-state lasing beyond the twostate lasing threshold. It was found that difference in electron and holecapture rates strongly affects light-current curve. Modulation p-type
doping is shown to enhance the peak power of GS lasing transition.

8552-2, Session 1

Ultrafast nonlinear dynamics insemiconductor optical amplifiers for opticalsignal processing (Invited Paper)
Yong Liu, Ligong Chen, Xiu Zheng, Shangjian Zhang, Rongguo
Lu, Univ. of Electronic Science and Technology of China (China)
Semiconductor optical amplifiers (SOAs) have been broadly used
as nonlinear elements for all-optical signal processing, where thenonlinearities in the SOAs have been utilized. To increase the operating
speed of the SOA-based optical switches, it is crucial to understandthe ultrafast nonlinear dynamics in the SOAs. The gain dynamics of
the SOA has been extensively studied. However, the phase dynamics
and chirp dynamics are not as clear as the gain dynamics. We present
the investigation results on the nonlinear phase and chirp dynamics in
SOAs. Time-resolved gain and phase dynamics of a quantum well SOA
are measured using 2 ps pump pulses into an integrated Mach-Zehnderinterferometer switch under a co-propagation arrangement. Ultrafast
component in the phase recovery is clearly observed. We explain theultrafast phase dynamic by using a field propagation numerical modelthat includes the impact of sub-picosecond intra-band effects of the
SOA. In addition, we numerically investigate the chirp properties of
the SOA in all-optical switches, and analyze the influences of chirp
dynamics upon the detuned-filtering-based optical switches that extract
the ultrafast chirp component to realize more than 160 Gbit/s opticalswitching. The results are very useful for SOA-based ultrafast opticalsignal processing in photonic networks.
We present the investigation results on the nonlinear phase and chirp
dynamics in semiconductor optical amplifiers (SOAs). Time-resolved
gain and phase dynamics of a quantum well SOA are measured using
2 ps pump pulses into an integrated Mach-Zehnder interferometerswitch. Ultrafast component in the phase recovery is observed. We also
numerically investigate the chirp properties of the SOA, and analyze theinfluences of chirp dynamics upon the detuned-filtering-based opticalswitches that extract the ultrafast chirp component to realize more than

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160 Gbit/s optical switching. The results are very useful for SOA-based
ultrafast optical signal processing in photonic networks.

8552-4, Session 1

An open-path semiconductor lasertransmissometer for smoke opacity
measuring (Invited Paper)Peng Shi, Ke Du, Institute of Urban Environment (China)
Opacity is an efficient gauge to evaluate obscuring effect and Particles
characteristics of smoke. An open-path laser transmissometer has been
fabricated to quantify the light opacity of smoke, which is operated infield environment. The 532nm laser emitted out from semiconductor
laser diode has been modulated as square wave pulses by an electronic
oscillator based on 555 integrated circuit chip. An optical transceivermodule has been developed which is based on an off-axis parabolic
mirror and a retro-reflector. The laser is expanded to parallel light beamand diverted to open atmosphere by a 90 degree off-axis parabolic
mirror. After transmitted the smoke, light beam is reflected back on
the same light-path by the retro-reflector. A Fast Fourier Transform
Filtering algorithm combining with modulating of laser has beendeveloped to exclude the Mie scattering effects of sunlight by particles
in the smoke. The returned light and light from laser source are both
detected by two photodiode detectors; detected signals are converted
by A/D convertor and then sent to the computer via a USB cable.
The opacity of smokes which consisted of fugitive dust is measured
by both Laser Transmissometer Method and Digital Optics Method
in filed campaign in Xiamen, china. There are 91% of the individual
absolute opacity difference values from April 26 that are < 15%, andLaser Transmissometer has much high temporary resolution than Digital
Optics Method.

8552-5, Session 2

VCSELs for exascale computing, computer
farms, and green photonics (Invited Paper)
Werner H. Hofmann, Philip Wolf, Technische Univ. Berlin(Germany); Wei Li, Technische Univ. Berlin (Germany) andInstitute of Semiconductors (China); Philip Moser, Gunter
Larisch, Technische Univ. Berlin (Germany); James A. Lott, VI
Systems GmbH (Germany); Dieter Bimberg, Technische Univ.
Berlin (Germany) and King Abdulaziz Univ. (Saudi Arabia)
The copper-induced communication bottleneck is inhibiting
performance and environmental friendliness of today´s supercomputers.
Vertical-cavity surface-emitting lasers (VCSELs) are ideally suited tosolve this dilemma. Global players like Google, Intel, HP or IBM are
now going for optical interconnects based on VCSELs. The required
bandwidth per link is given by Amdahl´s balanced system law anddepends on the architecture of the data center. According to Google,
a band¬width of 40 Gb/s has to be accommodated in the future.
IBM demands 80 Tbps interconnects between solitary server chips
in 2020. We recently realized ultra-high bit rate VCSELs up to 49
Gb/s suited for such optical interconnects emitting at 980 nm. These
devices show error-free transmission at temperatures up to 155°C andoperate beyond 200°C. Serial data-rates of 40 Gb/s were achieved
up to 75°C. Record high energy efficiencies close to 50 fJ/bit could
be demonstrated for lasers emitting at 850 nm. The devices were
fabricated using a full three-inch wafer process, and the apertures wereformed by proprietary in-situ controlled selective wet oxidation. All
device data were measured, mapped and evaluated by our proprietary
fully automated probe station. The bandwidth density of our present

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devices is scalable from reasonably 100 Gbps/mm? to a physical limit
around 15 Tbps/mm?. Still more energy-efficient devices dissipating
less heat are mandatory for further up scaling of the bandwidth. Novel
metal-clad VCSELs enable to reduce the footprint for ultra-short range
interconnects by 1 to 2 orders of magnitude enabling a similar increaseof device density and bandwidth.

8552-6, Session 2

Retreving alpha factor of semiconductor
lasers from a self-mixing interference
waveform (Invited Paper)
Yan Gao, Yanguang Yu, Jiangtao Xi, Univ. of Wollongong(Australia)
As an active research field, the self-mixing interferometry (SMI) basedon semiconductor lasers (SLs) is a highly promising and emerging
technique for non-contact sensing and parameter measurements ofSLs. The basic structure of an SMI system consists of an SL, a lensand an external target. When a portion of reflected light from the target
travels back to the laser cavity, a new lasing field is built up leading toboth amplitude and phase modulations. The modulated optical output
power, which is detected at the rear facet of laser diode, is called a selfmixing signal which carries the information of both the target and SL’s
feature parameters. Alpha factor, also known as linewidth enhancement
factor, is one of the most important SL’s feature parameters. It
characterizes the characteristics of SLs, such as the linewidth, thechirp, the injection lock range and the dynamic performances. This
paper presents a new method for retrieving alpha of SLs by making useof a self-mixing interference waveform. According to the well-known
Lang-Kobayashi (L-K) theory, the self-mixing interference waveform
is shaped by multiple parameters, including the alpha, the opticalfeedback level factor (denoted as C) and other parameters related
to the oscillation of the external target. In this work, we build a set of
new equations based on the SMI model derived from the L-K theory,
which can be used to calculate the alpha value. In existing SMI based
methods for measuring the alpha, there are two restrictions: the external
target is set in a single harmonic vibration and the C is limited within acertain narrow range. The proposed method is able to relieve these twolimitations. The associated simulations and experiments are carried out
for verifying the proposed method.

characteristics and their close interaction is provided by the photonic
integrated circuit simulator in 3D (PICS3D) software. The temperature
distribution contour is solved for the proposed structure with 4µm
aperture device under a driving current of 2 mA at temperatures of
358K and 300K. It is obviously shown that the proposed VCSEL
demonstrates a single-mode output power more than 0.4mW and a
3dB bandwidth more than 6.8 GHz even at 358K, which meets the twomost requirements of single mode output and high speed modulation athigh temperature.

8552-8, Session 2

Cavity optimization of 1.3 micron InAs/
InGaAs quantum dot passively mode-locked
lasersTianhong Xu, Paolo Bardella, Ivo Montrosset, Politecnico di
Torino (Italy)
Performance optimization of monolithic 1.3 micron InAs/InGaAsquantum dot (QD) passively mode-locked lasers of 3 mm long and
10 QD layers have been investigated systematically using the FiniteDifference Traveling-Wave (FDTW) model by changing simultaneously
the length of the saturable absorber (SA) and the cavity reflectivity.
Our numerical model describes in a rigorous way the dynamics of the
field propagating in the Fabry-Perot cavity consisting of a gain section
and a SA and the dynamics of the associated carrier distributions in
QD-based lasers. ML lasers designed with help of this model haveshown outstanding performances respect to more traditional structures.
In this work, we demonstrate that instead of the typically used low
value of the output facet reflectivity (5% to 1%), an appropriate higher
value of it with a proper length of the SA allows to achieve performance
improvement. Reduction in pulse width from 4.4 ps to 930 fs andincrease in the product of the peak power and the average power(figure of merit) from 0.012 W^2 to 0.2 W^2 were obtained. Clear design
guidance are extracted, which can be also exploited in the design oflasers with different length or QD layers.
Furthermore, we put in evidence that the pulse shape formation isdetermined not only by the gain/absorption saturation energy, but also
by the cumulative longitudinal gain/absorption saturation effects which
are related to the length of the gain/SA sections.

8552-7, Session 2

Our simulation results also confirm that reducing the ratio between
the unsaturable losses and the saturable losses would benefit the ML
performances of a laser.

High-temperature operating 795-nm VCSELs
for 87Rb chip-scale atomic clock8552-9, Session 2

Yongqiang Ning, Changchun Institute of Optics, Fine Mechanics
and Physics (China)
This paper reports the design and growth of high-temperature
operating 795-nm VCSELs with compressively strained InAlGaAsAlGaAs multiply quantum well (MQWs) which improves the power andmodulation performances at 358K. Compositions and thickness of the
InAlGaAs MQWs are optimized for operation at elevated temperatures.
Temperature sensitivity of the threshold current is estimated by thetemperature dependence of cavity-mode gain over a broad temperature
range (25oC-150oC).
VCSEL samples with three 6nm In0.125Al0.14Ga0.735As-Al0.3Ga0.7As
QWs and 32/45 pairs Al0.25Ga0.75As/Al0.9Ga0.1As p/n-type DBR
are grown by metalorganic vapor phase epitaxy (MOVPE) in an Aixtron
200/4 reactor on exactly oriented (001) GaAs substrates. Temperaturedependent DBR reflectivity spectra and photoluminescence (PL)showed a temperature-shift of 0.298nm/K for peak wavelength of PL
and 0.062nm/K for central wavelength of DBR reflectivity spectra.
Cavity mode wavelength is spectrally aligned with peak wavelength of
PL at 80oC (353K) which agrees with the calculated expectation.
A self-consistent VCSEL model based on quasi 3D finite element
analysis accounting for the electrical, optical, and thermal

The characteristics of spectral in verticalcavity surfacing-emitting lasers based on
defect layer structure
Bao Lu Guan, Beijing Univ. of Technology (China)
one-dimensional (1D) photonic crystal (PC) such as Bragg reflectors
spontaneously form a photonic band gap (PBG), which widens
considerably as the dielectric contrast increases, and would exhibit
vivid Bragg reflecting walls at the design wavelengths when the
periodicity of the dielectric matches the wavelength of the laser. The
PBG feature of the PC has attracted considerable interests for multiwavelength laser devices and display devices. It is possible to realize
a dual-wavelength VCSEL with a single defect layer such as AlGaAs
by employing a two-mode asymmetrical 1D PC device structure.
Here, we have proposed an inexpensive multbeam control method
using an asymmetric-PC structure with defect layer to get two or more
wavelengths simultaneously from a high-gain VCSEL. It is pointed outthat the defect layer matching in the composite mirror of a PC andasymmetric-PC structure could provide an extremely large difference inthe reflectivity between the two mode states. The EL spectrum of the
GaAs/Al0.9Ga0.1As asymmetric 1D PC structure with Al0.8Ga0.2As

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Conference 8552:
Semiconductor Lasers and Applications V
defect layer shows that one of the modes is centered near 980 nm andthe other near 930nm. The full width at half maximum (FWHM) of thedual-wavelength are 1 nm and 2.2 nm, respectively and the total optical
thickness of the microcavity device is about 4.5p. This structure can be
fabricated after growing an ordinary QW laser structure with a standard
epitaxial method. It is very simple and suitable for multibeam control.
In the field of nonlinear optics, this laser may be used as the source inspectroscopy and communications.

8552-10, Session 3

Design and optimization of the microwave
structures for multi-channel PICs’ packaging
using flip-chip method and LTCC substrate(Invited Paper)
Wei Han, Frank Hudson Peters, Tyndall National Institute(Ireland)In order to meet the high-speed, high-density, and low cost packaging
scheme for the future broadband and multichannel PICs, we havedesigned and optimized the packaging scheme using LTCC based
flip-chip technique. In this paper, the microwave model was built for
the LTCC substrate and the flip-chip structure using 3D distributed EM
method, in which different signal feeding structures were designed tocontrol the transmission loss and RF reflection. The RF crosstalk aswell the isolation was also investigated to provide an optimum signal
integrity situation for high-density integration which will also provide thedesign rules for the PIC fabrications. Finally, the LTCC substrates weremade and assembled with the dummy chips to validate our design.

8552-11, Session 3

Holding beam injection for improving
self-induced polarization rotation in asemiconductor optical amplifier (Invited
Paper)
Shangjian Zhang, Yali Zhang, Rongguo Lu, Shuang Liu, Yong
Liu, Univ. of Electronic Science and Technology of China (China)
Gain recovery is critical to ultrafast dynamics of a semiconductor
optical amplifier (SOA), which determines the working speed and output
quality of SOA-based all-optical signal processing functionalities.
It has been reported that slow gain recovery might lead to serious
signal distortions, pattern effects and degradation of extinction
ration (ER), and limit the operating speed to be lower than 40 Gbit/s
in high-speed communication systems. We propose a scheme toimprove the performance of self-induced polarization rotation (SPR)
in a semiconductor optical amplifier by holding beam injection. It isfound that the gain recovery time of TE and TM modes can be largely
reduced through an appropriate holding beam injection, with which the
response of SPR in the SOA for ultrafast signal can be speeded up. As
an example of validation, we apply a holding beam in the SPR-based
optical power equalization. Simulation shows that both the distortionof Return-to-zero (RZ) signal and the overshoot of Non-return-tozero (NRZ) signal due to the slow gain recovery of the SOA can besignificantly suppressed. After the power equalization, an extension
ratio (ER) improvement of 10 dB and 7 dB of RZ and NRZ has beenobtained respectively, and both signals can reach high quality with the
Q factor of eye-diagram over 20.
A scheme for improving the self-induced polarization rotation (SPR)
in a semiconductor optical amplifier (SOA) based on holding beam
injection is proposed. Gain recovery of TE and TM modes can be largely
accelerated through an appropriate holding beam injection, with which
the response of SPR in the SOA for ultrafast signal can be speededup. Holding beam injection is employed in SPR-based optical power
equalization as an example of validation, in which the distortion of RZ(return-to-zero)and the overshoot of NRZ (non-return-to-zero) signal are
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largely suppressed, and the extension ratio are improved by 10 dB and7 dB, respectively.

8552-12, Session 3

Single facet slotted Fabry-Perot laser and its
application in photonic integrated circuits(Invited Paper)
Hua Yang, Tyndall National Institute (Ireland)
to meet the exponentially growing demands on data transmission
capacity, dense wavelength division multiplexing (DWDM) technology
which multiplexes a number of optical carrier signals onto a single
optical fiber by using different wavelengths has been adopted by
optical communication systems and more channels and components
are introduced to improve the functionality. Monolithic photonic
integration circuits (PICs) in InP have provided an effective solution torealize multiple channels and advanced functions in the system levelwith compact size, lower power consumption, simpler coupling andpackaging, higher reliability as well as lower cost. In these systems,
single mode lasers, typically distributed feedback (DFB) or distrusted
Bragg reflector (DBR) lasers, are the indispensible components forgenerating the optical signals. However both require submicron gratings
which must be generated using time consuming and costly ebeam orholographic lithography.
Slotted FP lasers using the optical perturbation by one or multiple
slots etched into the ridge waveguide of the Fabry-Perrot lasers to
select the desired mode have been demonstrated as single modeand tunable. And by properly designing the multiple slots to provide
enough reflection necessary for lasing, single facet or facetless slottedlasers can be realized which are suitable for monolithic integrationin the PIC. These lasers are based on a single epitaxial growth witha simple fabrication process in which traditional photolithographic
techniques can realize the feature size of the slots of 1µm. In this paper,
we demonstrate a single facet slotted FP laser with single mode andtenability and its application in the PIC.

8552-13, Session 3

Opto-electronic hybrid integrated platform
for high-speed applications
Wei Han, Tyndall National Institute (Ireland)
In this work, a broadband Optoelectronic Modulator Module wasdeveloped to enable the fabrication of 40G broadband, low-cost, andcompact transceivers for telecommunications. In order to examine
the microwave performances of the proposed module, the equivalentcircuit method and 3D distributed electromagnetic model are employed.
In this module, an opto-electronic device such as a high-speed EAM
modulator is integrated with a RF interconnection circuit. A Kovar
heatsink with multistep structure is designed for ease of optical
coupling using a laser welding process. In order to control the highfrequency resonances and improve the signal integrity, AlN based
subcircuits are designed to feed the RF and DC signals separately.
The interconnection networks between the opto-electronic device andhigh-speed transmission lines are carefully investigated to optimize
the microwave performances. The influence of the packaging for thisopto-electronic integration platform on the microwave performance isalso analyzed in detail. The simulation results obtained and successful
fabrication of a transmitter module demonstrate that the proposed
platform can meet the requirements for high-speed WDM or TDM
systems.

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Semiconductor Lasers and Applications V

8552-14, Session 3

High-power narrow far-field broad-stripe
semiconductor lasers with second-order
metal grating feedback
Li Qin, YongYi Chen, Peng Jia, YongQiang Ning, Lijun Wang,
Changchun Institute of Optics, Fine Mechanics and Physics(China)In order to obtain high power semiconductor lasers with narrow far-field
and improve the quality of the output beam, a broad-stripe distributed
feedback semiconductor laser with second-order metal surface gratingsemitting around 940 nm is fabricated, based on the holographic
photolithography and wet etching technology. The second-order
metal gratings are located at the metal/semiconductor interface in the
p-Al0.2GaIn0.49P cladding layer, with 960 µm x 142 µm grating area,
and the metal gratings also act as ohmic contact of the p side, which
differs from traditional DFB-LDs. The grating period is 287 nm, thegrating depth is 100 nm, and the duty cycle is 0.5.
The characteristics of the semiconductor laser with second-order metal
surface gratings are tested under room temperature continuous-wave
conditions without any temperature-control device. For the laser withsecond-order metal gratings, the powers is 700 mW, spectral linewidth(FWHM) is less than 0.1 nm, lateral far-field angle (FWHM) is 2.7º andthe vertical far-field angle (FWHM) is 16.7° at the current of 1.5 A. For
the laser without gratings at a current of 1.5 A, the spectral linewidth is
1.3 nm, the lateral far-field angle is 7.3º and the vertical far-field angle is
36º, both worse than lasers with second-order metal surface gratings.
To improve the output characteristics, the DFB laser structure withsecond-order metal surface gratings was optimized by using themodified coupled-wave equations and COMSOL multiphysics.
In conclusion, because of the integration of second-order metal surface
gratings, the spectrum is narrowed and the far-field angles are reduced
greatly. This opens the way for the realization of watt-scale high-power
second-order metal surface grating edge-emitting and surface-emitting
lasers with high beam quality.

8552-15, Session 3

InGaAsP/InP DFB laser array monolithicallyintegrated with MMI combiner and SOA
Li Ma, Institute of Semiconductors (China) and Tsinghua Univ.
(China); Hongliang Zhu, Institute of Semiconductors (China);
Minghua Chen, Tsinghua Univ. (China); Can Zhang, Baojun
Wang, Institute of Semiconductors (China)
We developed compact (2.5mmx0.5mm) four-channel 1.55 um range
InGaAsP/InP wavelength-selectable microarray distributed feedback
laser diodes (DFB-LD’s) with a monolithically integrated multimodeinterference (MMI) optical combiner and a semiconductor opticalamplifier (SOA). The lasing wavelengths of four channels were changed
by varying width of ridge waveguides from 2 um to 3 um and the fourchannels can operate separately or simultaneously. Metal-organic
Chemical Vapor Deposition (MOCVD) was used for crystal growth
and a butt-joint technique was used to integrate the active MQW andpassive waveguide. Separation between two adjacent lasers was set
at 100um.The sine S-bends were 850-um-long. The MMI coupler is24-um-wide and 316-um-long. The length of SOA was 600um.1storder gratings were fabricated by normal holographic exposure and a
CH4:H2:O2 reactive ion etching (RIE) dry etching process. A shallow
ridge waveguide was used for lasers and amplifiers and a deep ridge
waveguide was used for the multimode interference optical combiner
and S-bend waveguide to reduce bending and radiation losses. The
250-nm-thick InGaAs contact layer was removed by a dry etchingprocess from electrical isolation areas, the S-bend and MMI regions inorder to obtain electrical isolation and reduce the absorption loss. At
25°C, the lasing wavelengths of the four channels were 1549.965nm,
1551.105nm, 1552.255nm and 1553.015nm, respectively. Side

mode suppression ratios of more than 35dB were obtained. A typicalthreshold current was around 35mA when the length of DFB LD was
690um. Output power of 1.86mW could be achieved when the injection
current of DFB LD and SOA were both 100mA at 25°C.

8552-16, Session 4

Time delay signatures of chaotic output in
1550nm VCSELs with variable-polarization
double optical feedback (Invited Paper)
Ping Xiao, Zheng-Mao Wu, Jia-Gui Wu, Long Jiang, GuangQiong Xia, Southwest Univ. (China)
In the last two decades, the optical chaos based on semiconductor
lasers (SLs) has received considerable attention for its applications
in secure communications, fast physical random bit generation andchaotic radar etc. Since high dimension chaos can be relatively
easily obtained by introducing time delay (TD) feedback, externaldelay feedback SL (EDF-SL) system has been regarded as a main
candidate in optical secure communication and physical random bit
generation. However, the chaotic output of an EDF-SL system usuallyretains obvious TD signatures, which inevitably affects the statistical
performance of random bit sequences and also may provide a possibleclue to the encryption attackers in chaos cryptosystem. Hence, theTD signature suppression becomes crucial both for improving thestatistical performance of random bit sequences and for ensuring thecryptosystem security.
In this paper, we theoretically investigate the TD signatures of chaos
output in a 1550nm vertical-cavity surface-emitting laser (VCSEL)
with variable-polarization double optical feedback (VPDOF) by using
self-correlation function (SF) and permutation entropy (PE). Throughsimulating the influences of polarized angle, feedback strength andinjection current on the TD signatures, the optimal parameters setting
for the TD signature suppression have been specified. We believethat this work would offer a high-efficiency, simple and practicable TD
signature suppression scheme for high speed random bit generationand chaos cryptosystem.

8552-17, Session 4

Photonics-assistant spectra shapingof ultra-wideband signals for dynamic
spectrum access in cognitive network(Invited Paper)
Jianyu Zheng, Ninghua Zhu, Lixian Wang, Jianguo Liu, Hui
Wang, Yuanxin Du, Institute of Semiconductors (China)
The dynamic control for the spectra of the Ultra-wideband (UWB)
signals, which is the key for implementing the dynamic spectrum
access in the cognitive radio, is still a challenge due to the limited
processing speed of the electronic devices. In this paper, we havesummarized our recent work about controlling the spectrum shapeof the UWB signals in optical domain, in addition to review the othergroups’ related research work. The experiment setups and results
based on nonlinear dynamics of the optoelectronic oscillator, transfer
response of the phase or polarization-to-intensity convertor and fourwave-mixing of the nonlinear optoelectronic device will be describedin detail respectively, in which the controllable frequency suppress
for the optical UWB signals at specific frequency positions were
implemented. Particularly, the UWB pulse with the special shape,
which corresponds to the 5-GHz band-rejection in frequency domain,
was generated in order to avoid the interference between UWB and
Wireless Fidelity system in practice. In addition, the UWB signals whose
center frequency could be continuously tuned and converted up to
the frequency range of millimeter wave were generated by utilizing
the polarization modulator based optical switch. The areas for future
development and the challenge of implementation of these techniques
for the applications in practice will also be discussed.

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Conference 8552:
Semiconductor Lasers and Applications V

8552-18, Session 4

Design of laser echo data acquisition system
based on USB2.0
Fuzhou Shang, Yong Song, Qun Hao, Wenlong Zhang, He Sun,
Beijing Institute of Technology (China)
As a new kind of PC Bus interface specification, USB is widely usedin data collection system. The technology of FPGA has its own
particular advantages, which has been widely used in the fields of dataacquisitions and image manipulation etc.
While collecting the echo signal of the laser and detecting object witha single APD, the data acquisition system based on the technology of
FPGA and USB2.0 was designed in this paper.
Firstly, the proposed research project of 3D-imaging radar is explained.
The project uses a 905nm pulsed laser diode as the laser sourceand detects object with a single APD to obtain instance images. The
hardware of the data acquisition system including APD, NE5210
amplifier, FPGA controller and USB interface circuit was designed andalso analyzed.
Secondly, the architecture of the USB was deeply analyzed firstly, andaccording to the scheme of the data acquisition system, the detailed
hardware and software design was introduced. In the hardware section,
the interface between the CY7C68013 and FPGA was introduced. In
the software section, the whole communication process of CY7C68013
in the slave FIFO mode were expounded; and the testing result of thefirmware was listed at the end of the firmware part; the design processof the driver for the USB was introduced here; Finally the application
software used to exhibit the curves and save data was designed.
Finally, the hardware and the software of the system were debugged,
the results of debugging were given and analyzed.

8552-19, Session 5

The modeling of comb spectrum stability inquantum dot lasers (Invited Paper)
Artem V. Savelyev, Mikhail V. Maximov, Alexey E. Zhukov, SaintPetersburg Academic Univ. (Russian Federation)
Lasers emitting low-noise broadband spectra formed by more thandozens narrow spectral lines (comb lasers) are very promising for anumerous applications. Though it has been shown experimentallythat quantum dot lasers have a unique property to generate stable
multimode spectrum, the origin of it remains unclear. Still the stabilityof the spectrum is the key issue for understanding laser dynamics
and further calculations of the laser properties. The goal of this paper
is to explain the stability of quantum dot laser spectrum in terms ofinterplay between homogeneous and inhomogeneous broadening andspatial interaction of longitudinal modes. It examines three aspects ofstability: modeling convergence, Lyapunov’s conditions and robustness
to small spectral losses variation. It is shown that the spatial modeinteraction is the major mechanism that ensures the spectral stability inthe presence of large homogeneous broadening. Moreover, if the latter
is taken into account assuming spatial uniformity no solutions stablein the mentioned means could be obtained. These results could be thestarting point in studying quantum dot laser’s dynamical properties
such as intensity noise.

8552-20, Session 5

40-Gbps random bit generation by
oversampling chaos from an injected
semiconductor laser (Invited Paper)
Xiao-Zhou Li, Sze-Chun Chan, City Univ. of Hong Kong (HongKong, China)

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Random bit generators are applicable to a wide range of areas
including numerical simulation, encryption, and secure communication,
where a high generation speed is often preferred. Semiconductor
lasers in chaotic oscillations have recently been utilized for random
bit generation with bit rates on the order of gigabits per second, far
exceeding those obtained from conventional electronics. However, inprevious works, the chaotic waveforms were usually generated fromsemiconductor lasers subject to optical feedback. The existence of
the internal feedback round-trip delay times had often led to residual
peaks in the autocorrelation at multiples of the delay times, whichwere detrimental to the randomness quality of the outputs. Different
approaches such as high-resolution analog-to-digital conversion,
bandwidth enhancement, and complicated post-processing wererealized to improve the randomness to sufficient quality, which
inevitably sacrificed the simplicity of the setups. Recently, as analternative, we have demonstrated random bit generation using asemiconductor laser subject to optical injection in lieu of opticalfeedback. The approach inherently avoids existence of any problematicdelay time. In this paper, we further report on oversampling the chaotic
signal that is recorded by an oscilloscope with 2.5-GHz bandwidthand sampled at 10 GHz, which is twice the Nyquist rate. This allows
retention of 4 least significant bits per sample point. After a bitwise
exclusive-or operation, output bits generated at 40 Gbps is shownto pass the National Institute of Standards and Technology Special
Publication 800-22 statistical tests of randomness. Oversamplingsignificantly alleviates the requirements on the electronic bandwidths.

8552-21, Session 5

Raman spectroscopy system with hollow
fiber probes
Binghong Liu, Yi-Wei Shi, Fudan Univ. (China)
A simple Raman spectroscopy system was realized using a flexible
hollow waveguide (HW) as laser emitting fiber and another HW as signal
collecting fiber. A silver-lined capillary waveguide has flat transmission
characteristic in the visible and near infrared wavelength region longer
than 500nm and little optical background fluorescence noise without
intrinsic Raman scattering compared with silica optic fiber duringtransmission, which would be of great significance to the detection in
low frequency Raman shift region. The complex filtering and focusing
system was thus unnecessary. The Raman spectra of CaCO3 andpolythene were obtained using our simple system with reasonable
signal to noise ratio without any lens and were compared with theresults detected by commercial optic fiber probe. In addition, we used
Ag HW as sample cell to detect liquid phase sample, we adopt a 6cm
Ag HF cell and direct forward butt-coupling system construction.
Experiment results show that such HW and simple system construction
can obtain very high signal to noise ratio induced by increasing opticallength between sample and laser light. We also give the elementary
theoretical analysis of using HW as sample cell, the parameters of thefiber which would affect the system were discussed. HW plays a good
performance for Raman detection and thus is allowed to be a potentialcommercial fiber probe and sample cell.

8552-22, Session 5

All-optical sampling towards high-speed
optical analog-to-digital conversion
Shangjian Zhang, Yali Zhang, Rongguo Lu, Shuang Liu, Heping
Li, Yong Liu, Univ. of Electronic Science and Technology ofChina (China)
All-optical sampling attracts considerable attention due to its crucial
applications in high-speed optical analog-to-digital conversion. Several
fiber-based optical sampling schemes have been demonstrated, suchas self-phase modulation, cross-phase modulation, four wave mixing
and Raman soliton self-frequency shifting. These schemes can provide
ultra-fast sampling speed, but suffer the high operating power and

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Semiconductor Lasers and Applications V
performance instability. Semiconductor-based signal processing is
promising because of low power consumption, high nonlinear efficiency
and potential large-scale integration. We propose and demonstrate
an all-optical sampling scheme using a single semiconductor opticalamplifier, in which the analog optical signal is sampled through thenonlinear polarization rotation arising in the semiconductor opticalamplifier. In the experiment, 40 GSa/s all-optical sampling for 2.5 GHz
analog optical signal is successfully demonstrated with commerciallyavailable fiber-pigtailed components. The all-optical sampling shows
the fundamental conversion efficiency of 1.35 and the total harmonic
distortion of 2.01% at the operating power of 5 mW. In the fullcharacterization, the output sampling signal demonstrates very goodsignal quality with the signal-to-noise ratio (SNR) of 38.1 dB and the
Signal to Noise and Distortion Ratio (SINAD) of 29.75 dB, which shows
an equivalent effective-number-of-bit (ENOB) of 4.65. Our scheme
requires only one semiconductor optical amplifier and has low power
consumption, which shows much potential for the high-speed opticalanalog-to-digital conversion.

8552-23, Session 5

0.5Gbits/s message bidirectional encryption
and decryption based on two synchronizedchaotic semiconductor lasers
Jia-Gui Wu, Zheng-Mao Wu, Tao Deng, Xi Tang, Li Fan, Yi-Yuan
Xie, Guang-Qiong Xia, Southwest Univ. (China)
Chaotic cryptography is an attractive technique for information
secure transmission at the physical layer. In particular, the opticalchaos communication using semiconductor lasers (SLs) has received
intensive attention because of its high relaxation oscillation frequency(several GHz) and direct compatibility with existing optical fiber
networks. In past years, many valuable theoretical and experimental
works have been performed on unidirectional information secrettransmission based on SL chaotic synchronization. However, such a
unidirectional communication is dissatisfactory, and bidirectional or
multidirectional secure communications are always highly expected.
In order to implement bidirectional chaos communication, various
system configurations have been proposed, where most of them arebased on the chaos synchronization between two mutually coupled
SLs (MC-SLs). Usually, some additional measures must be adopted
to strengthen the stability of chaos synchronization in such a MC-SLs
system. Very recently, we have experimentally reported a novel chaos
synchronization scheme between two independent SLs driven by acommon signal. Different from a MC-SLs system, there is no direct
coupling between the two synchronized SLs, which are only linked by acommon mediating SL.
In this paper, based on our recent reported chaos synchronization
scheme mentioned above, we propose and experimentally investigate
a bidirectional chaos communication system. Preliminary experimental
results show that the robust chaos synchronization between two
authorized SLs can be experimentally realized. Based on thischaos synchronization, by using the synchronized chaos signals as
communication carriers, two pseudo-random data streams with arate of 0.5Gbits/s can be encrypted into the chaotic carriers and be
effectively decrypted on both ends of the communication channel.

8552-24, Poster Session

The influence of sampling duty cycle
fabrication error in an SBG semiconductor
laser on its lasing wavelength
Yating Zhou, Changzhou Institute of Technology (China) andNanjing Univ. (China); Weichun Li, Rui Liu, Linlin Lu, Yuechun
Shi, Xiangfei Chen, Nanjing Univ. (China)
In order to investigate the influence of the sampling duty cycle
fabrication error on the lasing wavelength of an SBG semiconductor

laser, a monolithic integrated laser array is fabricated. In this laser array,
there are 56 p equivalent phase shift (EPS) SBG semiconductor lasers
laid out adjacently to each other in the same bar. Except the sampling
duty cycle of these lasers are designed and fabricated from 0.21 to 0.76
successively with a step of 1%, the cavity length, the sampling period
and seed grating period for each laser is the same. Furthermore, boththe two end facets of every laser are coated with ant-reflection coating(reflectivity 1%).
For these SBG lasers, the -1st channel is selected as the lasing
channel. Furthermore, for each laser the work temperature is controlled
at 25 oC by a thermoelectric cooler while the injection current is set as
70 mA keeping constant. In order to eliminate the impacts of random
end-facet phases on the lasing wavelengths of these lasers, linear fitting
curves of the lasing wavelengths versus sampling duty cycles is utilized.
The experimental results show that when the sampling duty cycle varies
from 0 to 100%, the lasing wavelength of an SBG semiconductor laser
increases about 0.5 nm. Due to the fabrication error of the sampling
duty cycle being not less than 2%, the lasing wavelength tolerance that
do not exceed to 0.01 nm, which can be ignored in an actual WDM
system.

8552-25, Poster Session

Thermal effects of pulsed pumping insemiconductor disk lasers
Peng Zhang, Teli Dai, Yiping Liang, Siqiang Fan, Yu Zhang,
Chongqing Normal Univ. (China)
It has been demonstrated experimentally that pulsed pumping cansignificantly improve the thermal management in an optically-pumped
semiconductor disk laser, and the output power of semiconductor disklasers under pulsed pumping can be upgraded to times of those undercontinuous pumping. This paper presents numerical analysis of thethermal effects of the pulsed pumping in semiconductor disk lasers,
so to theoretically disclose the details of the thermal processes ofthe pulsed pumping. In the simulation, the parabolic heat conduction
equation, which is widely employed to describe the transient thermaltransfer processes, is solved under cylindrical coordinates by the useof the finite element method, a time-dependent heat source of periodic
laser pulse train is assumed, and the maximum temperature rise in themultiple quantum wells active region is focused. The influences of thepulse shape, the repetition rate, and the duty cycle of the pumping
laser pulse train on the maximum temperature rise and the heat flux are
investigated respectively, and the results are compared with the caseof continuous pumping, i.e., the solutions of the time-independent,
elliptical steady heat conduction equation. To verify the applicability ofthis numerical modeling, some simulation results are compared with
reported data, and the theoretical results are in good agreement withthe experiments.

8552-27, Poster Session

A multiple excitation technique forfluorescence rejection in Raman
spectroscopy base on external cavity diodelaser
Hongwu Zhou, Zhijian Cai, Jianhong Wu, Soochow Univ. (China)
Raman spectroscopy is widely used in food-safety inspection, material
identification, chemical analysis and biomedical test. However,its applications are often limited by fluorescence disturbance. So,
it’s necessary to suppress the fluorescence background in Raman
spectroscopy, especially for biochemical Raman analysis. An obvious
characteristic difference between Raman signal and fluorescence isthat fluorescence spectrum is not sensitive to the change of excitation
wavelength while Raman signal will shift along with the excitation
wavelength in the spectrograph. Based on this principle, a Shifted
excitation Raman difference spectroscopy (SERDS) technique is

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Conference 8552:
Semiconductor Lasers and Applications V
recently developed for suppressing fluorescence, which has shown
good performance and broad suitability. Compared with otherfluorescence rejection methods such as laser bleaching method andtime resolved spectroscopy technique, SERDS has the advandagesof low cost, mininum sample selectivity and good compatibility withthe existing Raman instruments. The prevailing SERDS system usuallytakes two closely-spaced excitation wavelengths to illuminate thesample alternatively, and uses two spectra to generate the first-orderdifference spectrum, where the fluorescence background will becancelled out. The difference spectrum will then be processed by adeconvolution algorithm to reconstruct the normal Raman spectrum.
However, only two wavelengths are not sufficient to remove thefluorecence background completely and the data reconstruction by
first-order difference spectrum could be disturbed by electronic noises.
In order to reject the fluorescence better and to improve the signalto-noise ratio further, multiple excitation and higher-order difference
spectroscopy method could be used. In this paper, a multiple excitation
SERDS method for Raman fluorescence rejection is proposed. A
tunable laser system, which was constructed by a home-made Littrow
grating external cavity diode laser, was incorporated in a Raman
instrument to achieve multiple wavelength excitation. And the highorder difference spectrum was generated to remove fluorescencebackground. A robust algorithm based on iterative deconvolution withmultiple constraints was specifically developed for Raman spectrum
reconstruction. In this paper, the details of system design and algorithm
procedure were illustrated, and the simulation and experiment results
were presented, which demonstrated that this system could effectively
reject the fluorescence disturbance and greatly improve the signal-tonoise ratio of Raman measurement.

8552-28, Poster Session

Low threshold 980-nm tunable vertical-cavity
surface-emitting lasers
Shi Guozhu, Baolu Guan, Beijing Univ. of Technology (China)
Because of large, mode-hop free tuning range, low power
consumption, high integration density and the compatibility with current
optoelectronic fabrication processes, wavelength tunable vertical-cavity
surface-emitting lasers (VCSELs) have been of great interest in various
applications including optical networks, bio- or chemical molecularsensing technology, such as absorption spectroscopy, fiber Bragg
grating measurement and trace gas monitoring. Short-wavelength
tunable VCSELs can serve as efficient and low cost transmitters forwavelength-division multiplexing in the short distance reconfigurable
optical interconnect to provide larger bandwidth.
We present an electrostatic actuated 980nm tunable VCSEL basedon two-chip assembly method. The half-VCSEL and the mechanicalpart of the laser are fabricated separately and are assembled in a
final packaging step which allow for independent optimization of thetwo components to achieve optimum device performance for desired
application. From the measured result, we obtain the maximum output
power is 4.56mW with 14µm diameter oxide aperture in continuous
operation and the continuous tuning range is 6.8nm. Confocal laser
scanning microscope is used to detect the flatness and smoothness of
the MEMS membrane. The very smooth interface is fabricated between
the membrane and air gap in the resonance cavity owing to separate
optimization of the two parts of device, resulting in the threshold current
as low as 0.6mA. The free-spectral range of 42 nm and the threshold
gain versus air gap and resonance wavelength for experimental
configuration are obtained from theoretical calculation. A large tuning
range performance of the 980nm VCSEL is predicted by improving
resonance cavity design and fabrication process.

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8552-29, Poster Session

Wavelength tunable VCSELs based on
voltage-dependent birefringence of liquid
crystalWang Qiang, Baolu Guan, Beijing Univ. of Technology (China)
Tunable vertical-cavity surface-emitting lasers (VCSELs) have become
one of the key optical sources in optical interconnect, spectroscopy,
sensor techniques based on fiber Bragg gratings, especially in thedense wavelength division multiplexing (DWDM) system, owing totheir advantages, for instance, low cost, low consumption, easy
fiber coupling, large and mode-hop-free continuous wavelengths
tuning range. VCSELs incorporating micro-electro-mechanicalsystems (MEMS) structure for various actuation mechanisms, suchas electrostatic, thermal and piezoelectric actuation have beenpresented in recent years. However, the MEMS movable mirror layersof wavelength tunable VCSEL is fragile, instable and easily influenced
by mechanical vibration which will deteriorate the tunable performance.
Here, we present a widely tunable 850nm-range VCSEL structure
based on the voltage-dependent birefringence of the liquid crystal. An
intracavity liquid crystal layer is imbedded between the top DBR andthe active region as an electro-optic index modulator. Al0.98Ga0.02As
oxidization layer is employed above the active region for current andoptical confinement. Because of the voltage-dependent birefringence ofnematic liquid crystal, tunable VCSEL with an intracavity liquid crystal
layer is designed to develop the tunable performance and stability.
Tuning efficiency of 5.4nm/V and 20-nm tuning range are obtained fromtheoretical calculation. With increasing the thickness of liquid crystal
layer, the tuning efficiency increases, nevertheless, the optical loss inresonance cavity also increases. So we found that 1837nm is the mostsuitable thickness for compromise. Furthermore, the material gain
characteristics of the GaAs/Al0.3Ga0.7As quantum well and electricfield intensity in the structure layers are investigated, respectively. Our
study can provide insight into tunable VCSELs design and optimization.

8552-31, Poster Session

A novel four-section DBR tunable laser withdual-wavelength lasing
Liqiang Yu, Lingjuan Zhao, Dan Lu, Hongliang Zhu, Jiaoqing
Pan, Institute of Semiconductors (China); Yan Li, State Key
Lab. of Inf. Photonics & Opt. Commun., Beijing Univ. of Posts& Telecommun. (China); Wei Wang, Institute of Semiconductors(China)A novel dual-wavelength DBR laser is fabricated and investigated. The
DBR laser has four parts, a front gain section, a phase section, a DBR
grating section, and a rear gain section. The device material was grownon an n-InP substrate by the metal organic chemical vapor deposition.
The active region has separate confinement heterostructure withstrain-compensated InGaAsP-InGaAsP multiple quantum wells. The
wavelength detuning between the passive waveguide and the active
region is achieved by the quantum well intermixing (QWI) technique.
The facets of both sides were left as cleaved, and optical output fromthe front gain section was measured.
When the current injected into the front gain section is above thethreshold current, the device is working in single mode. Then dualwavelength can be obtained by adjusting the current injected into therear gain section. The wavelength detuning of two modes is about
0.73 nm, which corresponds to a beating frequency of 93 GHz. The
length of the front gain section, phase section, DBR grating section,and the rear gain section are 250 µm, 150 µm, 150 µm, and 250 µm,
respectively. When the laser is working on dual-wavelength lasing, thepower difference between the two modes can be less than 1 dB, andthe side-mode suppression ratio (SMSR) can achieve about 36 dB.
Moreover, the dual-wavelength can be tunable at the same time when
the current injected into the DBR grating section is adjusted. The device
can achieve a tuning range of at least 3 nm. Then when we maintain

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Semiconductor Lasers and Applications V
the current injected into the DBR grating section and tune the front gain
section and the rear gain section, the wavelength can be tuned slightly,
which is due to the currents induced the effective cavity length changeof the laser diode.

8552-33, Poster Session

Numerical simulation on output performanceof continuous-wave Raman silicon lasers
Hongxin Su, Lijing Xu, Xiaoming Li, Fuyun Jiao, Xu Li, Hebei
Univ. (China)
The potential of silicon as a photonic material for light generation has
attracted a great deal of attention owing to the demand for photonic
components that can be fabricated in a standard CMOS process.
Because Si is not naturally capable of accomplishing efficient radiative
recombination, stimulated Raman scattering (SRS) in silicon-oninsulator (SOI) waveguides has been discovered as an effective way
for optical amplification and lasing in SOI planar lightwave circuits,
and both pulse and continuous-wave (cw) Raman silicon lasers havebeen demonstrated experientially in recent years. To understand thephysical process of SRS lasing in SOI waveguides and to optimize
the performance of cw Raman silicon lasers, in this paper numericalsimulation on the output characteristics of cw Raman silicon lasers
with different parameters is performed based on power propagation
equations in SOI waveguides and boundary conditions. The output
powers as functions of the launched pump power, the gain length,
the reflectivity of the output end, and the effective mode area of the
SOI waveguide are presented. It is shown that two-photon absorption(TPA) and free-carrier absorption (FCA) lead to a significant reduction
to the output power of cw Raman silicon lasers, which is in good
agreement with the experimental reports. Numerical analysis predicts
that in the absence of TPA and FCA there are optimum values for thesilicon waveguide length, the effective mode area and the output end
reflectivity, respectively. The results can be used in the design of cw
Raman silicon lasers with high efficiency.

8552-34, Poster Session

The amplified spontaneous emission in EDF
with small pulse pumpWang Fu, Chongqing Wu, Lanlan Liu, zhi wang, zhenchao sun,yaya mao, Beijing Jiaotong Univ. (China)
Abstract: The Active Spontaneous Emission (ASE) is the importantnoise source for EDFA, affecting the EDFA based fiber laser seriously.
The theory and practice have shown that the ASE is closely related withpump methods, so the study on the ASE of EDF under the conditionof the pulse pumping has important academic significations. What’smore, the mode-locked laser based on EDFA fiber ring could bepumping by the pulse to realized mode-lock, and the ASE will impact
its characteristics. In this paper, the effects of pump pulse with different
width and amplitude on the ASE were investigated by the theoreticaland experiment methods.
Beginning with the carrier density rate equation,we can get each levelof the distribution of the number of particles carriers along with thechange of time.based on the relationship between the average numberof photons of the spontaneous radiation and the number of particles
carriers distribution. An approximate analytical solution of output
ASE noise average is derived when pump signal is small.Building anexperimental system, the results show that the output amplitude of ASE
is proportional to the input width of pump pulse when the pump pulse issmall.It’s also shows that the output amplitude of ASE is proportional tothe input amplitude of pump pulse. The new phenomena can be used
for the all-optical measurement of a pulse width.

8552-35, Poster Session

A high-power laser diode driver andcollimating optical system design for laser
3D imaging
Wenlong Zhang, Qun Hao, Yong Song, Fuzhou Shang, He Sun,
Tengfei Li, Beijing Institute of Technology (China)
In the paper,a design of driving circuit and collimating optical systemused for 3-D (three-dimensional) imagingdevice have been proposed. It
can improve the detecting range and precision of semiconductor laser
3-D imaging.
Propose the scheme of main driving circuit based on the model ofcapacitor charging and discharging. To get a high peak power laser
pulse with short pulse width and fast rise time, high speed power
MOSFET is used in the laser diode driver. Analyses on main influenceof the driving circuit are proposed. According to the corresponding
equation of the discharge circuit, which can be regarded as the nullinput-response series-would RLC circuit, the energy storage capacitor
C has been calculated. The parasitic inductance L is deduced, whichis the most influence of output waveform. In addition,the DC-DC
circuit which transforms the low input voltage to an DC high voltage
is designed, simulated and tested. Experimental results show thatthe maximum output peak current can be up to 20A when the energy
capacitor C is charged by DC-DC converter of 280V and the pulse
width is around 100ns.
According to semiconductor laser’s far field divergencecharacteristic,the aspheric collimation part has been designed by
optical design software ZEMAX. Far field beam trace and collimation
are simulated. The results of the simulation indicate that the RMS
divergent angle is 0.318mrad and the spot ismore uniform, which can
improve the efficiency of energy. The proposed system provides a basis
for further study of the three-dimensional laser imaging system.

8552-36, Poster Session

A balanced-detector optical heterodyne
detection for local-oscillator excess-noise
suppression
Jie Yang, Zhaohui Hu, Yuchi Zhang, BeiHang Univ. (China)
A semiclassical approach is used to calculate the principle and thesignal-to-noise density ratio for heterodyne detection utilizing two
optical detectors. These calculations show that excess-noise in thelocal-oscillator can be canceled and the balanced-detector optical
heterodyne detection requires less local oscillator power comparedwith the traditional single-detector optical heterodyne detection. An
experimental demonstration of excess-noise cancellation is reported.

8552-37, Poster Session

Speckle characteristics of a broad-area laser
diode
Shengtao Zhang, North Univ. of China (China); Xuyuan Chen,
Vestfold Univ. College (Norway); Pengfei Zhao, Wenhong Gao,
Yunbo Shi, North Univ. of China (China)
The speckle measurement setup consists of a semiconductor laser
diode (LD), a polarizer, a rectangular aperture, a scattering screen and a
CCD with lens. The laser diode used is the blue laser product of Nichia
with center wavelength of 450nm. The intensity of the incident laser
light onto a diffuser is controlled by using polarizer or adjusting input
current. The rectangular aperture with dimensions of 10mm*10mm
close to diffuser is used to select different parts of laser light field
as illumination spot. The distance between rectangular aperture and23A  Previous

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Conference 8552:
Semiconductor Lasers and Applications V
laser diode without depolarization is set to 465mm. The CCD with the
pixel size of 5.6um*5.6um is used to capture the speckle pattern, andthe lens with focus length of 50mm has an F number of 22. The laser
light field formed on the plane surface of the rectangular aperture hasdimensions of 430mm*30mm. The speckle contrast of the different
parts selected by aperture is measured, which has the values from 0.92
to 0.96. However there is no obvious trend (turn up or down) along the
movement of rectangular aperture. So when the laser diode operates
at its typical power output condition, the speckle contrast measured
approximately equals 1, while the speckle contrast is depressed about
to 0.2 when the laser diode operates with low driving current.

8552-38, Poster Session

Research on the performance of opticalcommunication system based on PolSK withbalance detection
Dan Liu, Zhi Liu, Puyao Wang, Xin Zhou, Changchun Univ. of
Science and Technology (China)
The paper proposes polarization shift keying (PolSK) technology basedon analysis polarization characteristics of the optical wave. Polarization
shift keying (PolSK) technology is a new standard digital modulation
technique in optical communication field. In this paper, atmosphericlaser communication system based on circular polarization shift keying(CPolSK) with balanced detection is constructed, we use the left andright circularly polarization states of optical wave representation logic
signal ‘ 0 ’ and ‘ 1 ’.Simulate and contrast OOK systems and PolSK
system with single receiver and CPolSK system with balance detection,
analysis of the performance of communication systems. The results
showed that, optical communication based on CPolSK has a uniqueadvantage in the field of free-space optical communication. Waveform
amplitude of signal received by CPolSK system with balance detection
is tow times OOK system and PolSK system with single receiver. And
in the same simulation parameters, the performance of CPolSK systemwith balance detection is far superior to the OOK system see fromeye diagram, and the bit error rate of CPolSK system is also decrease
tow order of magnitude. From this we can see that, Atmospheric laser
communication system based on PolSK can effectively improve theperformance of the communication system, and it has broad space fordevelopment and application in the free space optical communication
field in the future.

8552-39, Poster Session

Three-dimensional finite element modellingof conductive silver ink tracks thermally
cured on flexible substrates by repeating
irradiations of Nd:YAG laser at the
wavelength of 532 nm
Liwei Fu, Shuo Shang, Eamonn Fearon, Stuart Edwardson,
Geoff Dearden, Kenneth Watkins, Univ. of Liverpool (United
Kingdom)of laser beam scan and protection of heat-sensitive polymer substrate
due to its high transparency to the wavelength at 532 nm.
This work presented in this paper is a 3-D Finite Element Modelling(FEM) based investigation into a DPSS Nd:YAG laser with a top-hat
beam curing a particulate silver ink track on top surface of Polyethylene
terephthalate (PET) substrate at the wavelength of 532 nm. Key physicalproperties of materials have been defined in heat transfer module within
COMSOL multiphysics 4.0 environment, a Time-dependent solver has
been chosen for modelling a 3 pass curing mechanism, which the firstpass of laser scan removes the solvent, the second pass cross links
the resin complex, and the third pass increases the degree of interparticle connections as a result of resin complex further cross links.
The modelling results have been compared to the experimentation forevaluations and suggested sets of working parameters that optimizing
the balance between fast processing speed and good curing quality inindustrial manufacturing.

8552-40, Poster Session

Adaptive optics system based on magnetic
fluid spatial light modulator applied in laser
communication
Xiaolong Ni, Changchun Univ. of Science and Technology(China)Abstract: Laser communication is a potentially attractive technologythat can offer intrinsically high data rates and resistance to jamming,and facilitates low probability of interception and low probability ofdetection.In laser communication system,the wavefront aberrations
caused by atmospheric turbulence cause many negative influence.
This paper presents a new method based on magnetic fluid spatial
light modulator(MFSLM) to cancel dynamic wavefront aberrations inlaser communication system. MFSLM have been found particularly
suitable for imaging systems where they can be used to compensate
for the complex optical aberrations. Experimental results showing theperformance of a multi-channel closed-loop adaptive optics system arepresented. The resulting distortions lead to enhance signal power anddecreased bit error rate (BER).

8552-41, Poster Session

Study on the optical antenna for laser
communication network
Fu Qiang, Changchun Univ. of Science and Technology (China)
with the urgent needs of the development of high-resolution
observation techniques and high data rate transmission of information,
studying all-optical network the high-speed laser communication isiminent.
This article describes the advantages of a space laser communication
technologies and development trends, optical antenna for laser
communication network, to provide a new way on space laser
communication link network.

Particulate silver inks are made of three basic components: silver flakes,
resin complex, and organic solvent, and they are finding increasing use
in the direct manufacture of electronic circuitry applications such as
conductive traces on Printed Circuit Boards (PCBs), the antennas on
Radio-frequency identification (RFID) tags, and the grid wires on strain
gauges. Curing by repeating laser irradiations at the wavelength of 532
nm is advantageous for reasons of fast processing speed, good curing
quality due to a reduced track’s electrical resistivity by multiple passes

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8552-42, Poster Session

Performance comparison study ofmodulation in laser communication system
Jianhua Liu, Fu Qiang, Changchun Univ. of Science andTechnology (China)
There were many ways of modulation in the laser communication
system. In order to verify that PolSK modulation was the most suitable
technology for space laser communication system, we analyzed theimplementation principle of several signal modulation ways in thispaper. By combing the theoretical analysis and software simulation,
we make an analysis and comparative study through five aspects inthe function of the PolSK modulation and the traditional modulation
ways, including transmission rate in the unit, bandwidth requirements,
transmission capacity, the average power utilization and error
performance. The results indicated that PolSK modulation possess ahigher transmission rate in the unit, a lower bandwidth requirements,
and a larger transmission capacity. The most important thing was thatPolSK modulation mode had a superior performance and a strong
anti-air channel interference activity compared with the traditional
modulation in a weak turbulence conditions. So PolSK modulation
mode was suitable for laser communication system.

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Conference 8553:
Optics in Health Care and Biomedical Optics V
Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8553 Optics in Health Care and Biomedical Optics V

8553-1, Session 1

8553-4, Session 1

Optical imaging for mouse brain
connnectivity (Invited Paper)

Motion compensation of optical mapping
signals from beating rat heart slices (Invited
Paper)

Qingming Luo, Britton Chance Ctr. for Biomedical Photonics(China)This presentation will give an overview of optical imaging for mousebrain connnectivity, and will focus on progress of my group on MOST
for brain connnectivity.

B. Stender, Univ. zu Lübeck (Germany); M. Brandenburger,
Fraunhofer Research Institution for Marine Biotechnology EMB(Germany); B. Wang, Z. X. Zhang, Xi’an Jiaotong Univ. (China);
Alexander Schlaefer, Univ. zu Lübeck (Germany)
Introduction

8553-2, Session 1

Imaging neurons with inertia-free beamsteering of the femtosecond laser pulse(Invited Paper)
Shaoqun Zeng, Britton Chance Ctr. for Biomedical Photonics(China)We will show how the femtosecond laser pulse changes its
characteristics after passing an angular device, and how thisinformation is used to implement an inertia-free beam steering, andhow such techniques can be used to measure the fast neuronal activity
and to achieve high throughput high resolution imaging for neuronalconnectivity studies.

8553-3, Session 1

Integrated on-chip lens applied tomicrofluidic chips (Invited Paper)
Qin Li, Yingying Zhao, Xiaoming Hu, Dongfang Yang, Beijing
Institute of Technology (China)
The optical signal on microfluidic chip is hard to be collected. On-chip
microlens is the potential choice to improve the collecting efficiency.
Optical fiber assembled on chip also can increase the signal detection
quality. Therefore, the combination of optical fiber and microlens could
get much stronger signal on chip. However, the matching between
optical fiber and microlens is a tough work. And if we hope to design
the one-off chip for medicine test, the fabricating cost of chip should
be considered. This article introduced a simple, inexpensive fabrication
method to make polymer and air integrated microlens to increase
the couple rate of optical fiber. This small element can improve theoptical signal detection and could be used to a blood cell counting
system based on microfluidic chip. Compared to other establishedprotocols, this procedure allows a simple, miniaturizing and inexpensive
microlens fabrication with high reproducibility. The on-chip microlens
was designed by Zemax software and tested by numerical simulation
to optimize the parameters. The air microlens was produced by using
direct lithograph of SU-8 resist. The couple effect showed that thesingle microlens was possible to reduce the beam divergence of opticalfiber. So the export light beam can be focused into a very small point
to satisfy the needs of excite the fluorescence of cell. On the other
hand, the strength of emission or scattering light coupled into opticalfiber also could be increased by the help of the on-chip microlens. The
fabrication method does not require any assembly process or external
driving forces. To fabricate the polymer and air microlens with different
focus, we only need to change the figures on masks. This technique
can be used in a variety of applications owing to its ability to achievecustomized microlens for specific applications.

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Monitoring the state of myocardial tissue over time is essential
to quantify the effects of new pharmacological substances or toperform toxicity tests. The use of mammalian cardiac tissue slices
as multicellular model has already been demonstrated, [1, 2, 3].
Typically the slices are grown on a microelectrode array (MEA) torecord electrophysiological signals. Another option to measure cardiac
excitation with high spatial resolution is optical mapping, [4]. We
introduce a technique to noninvasively record simultaneously opticalmapping data and motion of the rat heart slices.
Methods
A rat heart was excised and cut into short-axis slices. The slices were
stained with Di-4-ANEPPS and placed in warm oxygenated Tyrode’s
solution. The heart slices were beating first autonomously and thenvoltage controlled stimulated. Optical mapping data were recorded foreach slice with 295fps during both phases.
The motion of the rat heart slices was determined from the images
in four steps: First the translation was determined using a 2D affine
registration algorithm. Due to the radial nature of the periodic slice
contraction we decided to perform a coordinate transformation topolar coordinates on the affine registered images. In the third step thedeformation was calculated using a nonrigid B-Spline registration.
Finally the resulting images were transformed back to cartesian voxel
positions. The approach was implemented in Matlab.
Results
We compared traces of the fluorescence difference signal with andwithout compensation of the detected motion. We could determine asignificant reduction of motion artefacts. In addition the temporal traceof the myocardial defor-mation was similar to the course of force signals
recorded during previously performed experiments with rat heart slices.
Conclusion
Optical mapping of cultured rat heart slices in combination with opticalmotion tracking makes it possible to monitor the myocardial viability
state of a multicellular model with high spatial resolution. Future work
will focus on evoked arrhythmia.
References[1] M. Brandenburger, J. Wenzel, R. Bogdan, D. Richardt, F. Nguemo, M.
Reppel, J. Hescheler, H. Terlau, and A. Dendorfer, “Or-ganotypic slice
culture from human adult ventricular myocardium”, Cardiovasc. Res.
93(1):50-59, 2012.
[2] A. Bussek, E. Wettwer, T. Christ, H. Lohmann, P. Camelliti, U.
Ravens, “Tissue slices from adult mammalian hearts as a model for
pharmacological drug testing”, Cell. Physiol. Biochem. 24:527-536,
2009.
[3] W. Habeler, S. Pouillot, A. Plancheron, M. Puceat, M. Peschanski, C.
Monville, “An in vitro beating heart model for long-term assessment ofexperimental therapeutics”, Cardiovasc. Res. 81:253-259, 2009.
[4] Eds. D.S. Rosenbaum, M. Jalife, “Optical Mapping of Cardiac
Excitation and Arrhythmias”, Futura Publishing Compony, New York,
2001.

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Optics in Health Care and Biomedical Optics V

8553-5, Session 2

Multifunctional activatible microbubbles
for multimodal imaging and image-guided
therapy (Invited Paper)
Ronald X. Xu, The Ohio State Univ. (United States) and Univ.
of Science and Technology of China (China) and Chongqing
Medical Univ. (China)
Background: The therapeutic outcome of many anti-cancer drugs isvery low. The poor clinical outcome is partially caused by the low drugdelivery efficiency to the tumor site via the Enhanced Permeability andRetention (EPR) effort and is further complicated by tumor hypoxia that
increases the tumor resistance to chemotherapies.
Method: We have fabricated multifunctional drug-loaded microbubbles
for image-guided active delivery of oxygen and drugs to the tumor sitewith the increased efficiency. The microbubbles were fabricated byvarious processes such as micro-emulsification, co-axial electrospray,
and co-axial flow focusing. The surface of the microbubbles weremodified for cancer targeting. Anti-cancer drugs, imaging agents, andoxygen were loaded in the microbubbles. Upon exposure to ultrasoundpulses, the microbubbles were broken and the therapeutic/imaging
payloads were released. Optical and ultrasonic imaging tools were used
to monitor the microbubble activation process.
Results: Both lipid and poly lactic-co-glycolic acid (PLGA) microbubbles
were fabricated and tested. The surface of the microbubbles wereconjugated with various cancer-targeting ligands, such as a CC49
antibody(targeting TAG-72 antigen), an anti-VEGF antibody (targeting
VEGF), and a Luteinizing Hormone Releasing Hormone analog(targeting LHRH peptide). Oxygen, gene, and anti-cancer drugs wereencapsulated in the microbubbles. Upon exposure to 1 MHz ultrasoundpulses, the oxygen and the therapeutic payloads were released fromthe microbubbles. The activation process was monitored by ultrasoundand fluorescence imaging.
Conclusion: The multifunctional activatible microbubbles can bepotentially used for image-guided active delivery of anti-cancer
therapies.

8553-6, Session 2

Scanning optical microscope for samples
introducing spatially varying aberrations into
the illumination beam (Invited Paper)
Bosanta R. Boruah, Abhijit Das, Indian Institute of Technology
Guwahati (India)
Scanning optical microscope such as a laser scanning confocal
microscope, when employed to image biological specimens, often
suffer from specimen induced aberrations. The aberrations in turn
reduce image contrast and degrade the signal to noise ratio. Hence theillumination beam needs to be pre-corrected for the specific aberrations
to be introduced by the sample in order to retrieve the image quality.
It is easy to construct a microscope that has a single pre-corrected
illumination beam profile for the entire image frame. Unfortunately
specimen induced aberrations may vary from region to region such thatone pre-correction profile may not produce the best image over theentire field of view. Hence in such cases the illumination beam needs
to be pre-corrected using phase profiles that may vary from region
to region. In this paper we describe the design of a scanning optical
microscope with binary hologram based beam scanning where theillumination beam can have phase profiles that can vary from pixel topixel. The binary hologram is implemented by a liquid crystal spatial
light modulator (LCSLM). For a given specimen we first measure thevarious aberration co-efficients introduced by the specimen on a pixel
to pixel basis. The measured aberration co-efficient matrix is thenused to construct an appropriate hologram for each of the pixels in
the imaged area. The sequence of holograms when displayed on the
LCSLM, lead to an illumination beam scanning over the sample, thathas a region specific correction phase profile. We will present here
preliminary experimental results obtained using proposed system.

8553-7, Session 2

Fluorescence holography with two sphericwaves produced by a spatial light modulator
Shaoqun Zeng, Britton Chance Ctr. for Biomedical Photonics(China); Xiaomin Lai, Huazhong Univ. of Science andTechnology (China)
Holographic fluorescence imaging is very promising as it can obtain
three-dimensional fluorescence imaging without scanning. However,current method usually recorded holograms far from the image plane,
with the fluorescence decays when spreading broadly. Here we show
the fluorescence holography with two spheric waves shows high signalto-noise (SNR) ratio over other configuration such as one plane wave
and one spheric wave. This provide better performance in fluorescenceimaging for the biological samples.

8553-8, Session 2

Parallel localization of multiple emitters forfast localization microscopy
Yina Wang, Wuhan National Lab. for Optoelectronics (China);
Zhen-li Huang, Huazhong Univ. of Science and Technology(China)Using the strategy of separating close-packed fluorescence emitters
into hundreds or even thousands of image frames, localization-based
super-resolution fluorescence microscopy naturally scarifies its
temporal resolution to obtain ultra-high spatial resolution, thus limits theversatility of this technique in studying dynamic processes inside living
samples. A possible approach to minimize this limit is high-density
localization microscopy, which increases the density of active emitters
so that each image frame samples more molecules. Recently, a numberof high-density localization methods have been reported that can
retrieve emitter positions when multiple emitters overlap. However, allthese methods suffer from either weak localization performance or slow
image processing speed, thus obstruct widely uses of these methods inlocalization microscopy.
In this talk we will introduce a new high-density localization method,termed PALMER for “PArallel Localization of Multiple Emitters via
Bayesian information criterion Recommendation”. This method comesfrom the combination of GPU parallel computation, multiple-emitter
fitting, and optimal model recommendation via Bayesian Information
Criterion (BIC). Compared to DAOSTORM, a representative high-density
localization method, the PALMER method shows an overall better
localization accuracy performance and an order of magnitude faster
analysis speed. Meanwhile, compared to conventional localization
microscopy, high-density localization microscopy based the PALMER
method allows a speed gain of up to ~14-fold in data acquisition withthe same desired Nyquist resolution. We believe that this PALMER
method has great potentials in pushing forward the field of fast
localization microscopy.

8553-9, Session 2

Coherent fiber supercontinuum laser for
nonlinear biomedical imaging
Haohua Tu, Yuan Liu, Univ. of Illinois at Urbana-Champaign(United States); Xiaomin Liu, Jesper Lægsgaard, Dmitry
Turchinovich, Technical Univ. of Denmark (Denmark); Stephen
Boppart, Univ. of Illinois at Urbana-Champaign (United States)

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Conference 8553:
Optics in Health Care and Biomedical Optics V
The last decade has witnessed an increased application of
femtosecond (or picosecond) solid-state lasers and closely
related optical parametric oscillators (or amplifiers) in label-freebiomedical imaging. Representative techniques include multiphoton
autofluorescence, stimulated Raman scattering, stimulated emission,and nonlinear absorption. With the rapid advancement of ultrafast
spectroscopy, similar molecular specific nonlinear imaging techniques
will continue to emerge. However, ultrafast solid-state lasers are oftenbulky, expensive, and alignment-sensitive, restricting these techniques
to dedicated optical laboratories. Also, daily laser operation demands
training and experience far beyond that of regular clinical staff. To
translate these techniques to the clinic (e.g., point-of-care diagnosis
and imaging), there is a critical need to replace the solid-state lasers
with portable, low-cost, low-maintenance, and environmentally-stablefiber lasers.
Unfortunately, conventional ultrafast fiber lasers have narrow gain
bandwidth, so that the emission is typically limited to a few discrete
wavelengths of rare earth dopants, such as ~1040 nm (Yb), ~1550
nm (Er), and ~2000 nm (Tm). To address this key limitation, we havedeveloped a supercontinuum source based on dispersion-engineered
photonic crystal fibers, which converts 1040 nm femtosecond pulses(pump) to a targeted wavelength (signal) anywhere inside the UVvisible-IR region of 350-1700 nm. In sharp contrast to traditional
supercontinuum generation that loses coherence between the pumpand signal, this source preserves the coherence, and thus behaves likea fiber analogue of optical parametric oscillators. The demonstrated
frequency up- and down-conversion of a fixed-wavelength ultrafast
fiber laser facilitates the envisioned clinical translation of this coherent
fiber supercontinuum source for nonlinear biomedical imaging.

8553-10, Session 2

Wide field-of-view microscopy with Talbot
pattern illumination
Jigang Wu, Guangshuo Liu, Shanghai Jiao Tong Univ. (China)
Wide field-of-view (FOV) microscopy is useful for high-throughput
applications because of the capability to obtain large amount of
information from a single image. One way to implement a wide FOV
microscope is to scan the sample with a two-dimensional focus grid.
The transmission or reflection of the focal spots can then be used toreconstruct the sample image. This scheme is effectively a parallel
scanning optical microscope (SOM), where the FOV depends on thearea of the focus grid and the imaging resolution depends on the
spot size of the foci. We use the Talbot image of a two-dimensional
aperture grid as the focus grid and developed a wide FOV microscope.
Preliminary experimental results show the capability of our microscopeto acquire wide FOV images of US air force target and green algae
samples.
Because the diffraction of incident beam by the aperture grid contains
complicated angular frequencies, the focal spots in Talbot pattern
cannot be approximated as Gaussian beams as in conventional SOM.
We characterized the focal spots in Talbot pattern and studied theevolution of the full width at half maximum (FWHM). We also simulated
the SOM imaging under Talbot pattern illumination using the razor
blade and the US air force target as the sample objects, and compared
the results with those performed with Gaussian beams as illumination.
Using several foci searching algorithms, the optimal focal distanceswere found to be shorter than the theoretical Talbot distances. The
simulation results were consistent with the experiment results.

8553-11, Session 3

Interstitial laser irradiation inphotoimmunotherapy (Invited Paper)
Wei R. Chen, Univ. of Central Oklahoma (United States);
Xiaosong Li, First Affiliated Hospital, Chinese PLA General
Hospital (China); Jessica Goddard, Univ. of Central Oklahoma
Return to Contents(United States); Roman Wolf D.V.M., Eric Howard, Univ. of
Oklahoma Health Sciences Ctr. (United States)
In situ photoimmunotherapy was developed to treat metastatic
cancers. It uses a combination of laser irradiation and modifierbased immunotherapy, to induce tumor-specific immune responses.
Previously, in situ administration of a light-absorbing dye has beenused to achieve non-invasive, selective laser photothermal destructionof tumor cells, as an integral part of the photoimmunotherapy. To
extend the applications of photoimmunotherapy for deep tumors
and/or tumors in internal organs, we developed interstitial laser
irradiation using a cylindrical diffuser. The thermal effect of theinterstitial photoimmunotherapy was studied using magnetic resonancethermometry and its immune effect was studied using an animal modelwith metastatic mammary tumors. Our results indicated that interstitial
irradiation could be controlled to induce the desired thermal effects. In
combination with the immunotherapy, interstitial irradiation is effectivein the stimulation of host immune responses to fight against local andmetastasized tumors.

8553-12, Session 3

Indirect photobiomodulation in functional
networks (Invited Paper)
Timon Cheng-Yi Liu M.D., South China Normal Univ (China);
En-Xiu Wei, Xiang-Bo Yang, South China Normal Univ. (China)
Photobiomodulation (PBM) is a non-damaged modulation of laser
irradiation or monochromatic light (LI) on a biosystem function. It
depends on whether the function is in its function-specific homeostasis(FSH). A FSH is a negative-feedback response of a biosystem tomaintain the function-specific conditions inside the biosystem so thatthe function is perfectly performed. A function in its FSH or far fromits FSH is called a normal or dysfunctional function. The process of afunction from dysfunctional to normal is called functional normalization.
Low level LI (LLL) can not directly affect a normal function, but may
self-adaptively modulate a dysfunctional function until it is normal. A
normal function in its FSH is maintained by a network of subfunctions
which mainly include its FSH-essential subfunctions (FESs) and its
FSH-non-essential subfunctions (FNSs). For a biosystem in a FSH, all
the FESs of the normal function are normal, but only some of FNSs
are normal. The quality of a FSH is also called the functional fitness ofthe normal function. The more the normal FNSs of a normal function
and the higher the FNS fitness, the higher the functional fitness of thenormal function. Through redundant pathways, LLL may self-adaptively
modulate a dysfunctional FNS of a normal function until it is normal andthe normal function is then upgraded. This PBM is called indirect PBM(iPBM). The iPBM on tumor cells, myoblast cells and fibroblasts andtheir applications will be reviewed in this paper.

8553-13, Session 3

Blue light rescues mice from fatal
pseudomonas aeruginosa burn infections:efficacy and mechanism (Invited Paper)
Tianhong Dai, Massachusetts General Hospital (United States)
Blue light has attracted increasing attention due to its intrinsic
antimicrobial effect without the addition of exogenous photosensitizers.
However, the use of blue light for wound infections has not been
established yet. In this study, we demonstrated the efficacy of blue
light at 415 nm for prophylaxis of lethal Pseudomonas aeruginosaburn infection in mice. In vitro study indicated that an average
7.64-log10-cycle reduction in the colony forming units of P. aeruginosa
was achieved after 109.9 J/cm2 blue light had been delivered to P.
aeruginosa suspensions. Transmission electron microscopy revealed
apparent steps in blue light mediated damages to P. aeruginosa cells.
Fluorescence spectroscopy suggested that coproporphyrin III or/and
uroporphyrin III are the intracellular photosensitizing chromophores

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associated with the blue light inactivation of P. aeruginosa. In vivo
study using bioluminescence imaging technique showed that a single
exposure of blue light at 55.8 J/cm2, applied at 30 min after bacterial
inoculation to the infected mouse burns, reduced bacterial burdenin mouse burns by an approximately 100-fold (P<0.0001). Survival
analysis revealed that blue light prophylaxis increased the survival rateof infected mice from 18.2% to 100% (P<0.0001).

Hospital (China); Ying Wang M.D., Ying Gu, Chinese PLA
General Hospital (China)

Photodynamic therapy (PDT) is an emerging therapeutic modality basedon the generation of highly reactive singlet oxygen through interactionsof photosensitizer, light, and molecular oxygen. As PDT techniques
continue to develop and find morepotential clinical indications andother new applications, robust dosimetry becomes a critical factor
for achieving satisfied treatments. In this review, the advantages andlimitations of each available PDT dosimetric method will be presented.
In particular, we highlight the recent advances inoptical monitoring
technologies for real-time clinical PDT dosimetry, and the singlet
oxygen luminescence dosimetry will be emphasized in details. Finally,
the future challenges in clinical PDT dosimetry will be discussed.

[Ru(bpy)2(dppn)]2+, one of Ru(II) polypyridyl complexes, present
inner dicationic charge and high 1O2 quantum yield. In this study,
the synthetic compound was used as photosensitizer (PS) tophotoinactivate a reference strain of Staphylococcus aureus ATCC
25923. Bacterial suspensions consisting of 108 colony-forming units(CFUs) per milliliter were incubated with PS of different concentrations(0.025µM ~ 25µM). After a 30 minutes period, the suspensions were
exposed to 457nm laser light, determined by the absorption spectraof the PS in PBS, with a power density of 40mW/cm2 for 10 minutes(energy density of 24J/cm2). PS group, light group and the blankcontrol were also concerned. Viability of bacteria was determined bypour plates. The Log10 reductions were calculated and killing effects
in photodynamic inactivation (PDI) group were analysed contrast to theblank control. We observed that neither the laser light nor the PS per
se had any inhibitory effect on the viability of the bacteria. PS at low
dose (0.025µM) followed by illumination yielded no significant decreasein the viable number. PS at 0.25µM and 2.5µM with irradiation induced
reductions of 1.69 Log10 and 5.97 Log10, respectively. PS at 10µM
and 25µM combined with light brought viable bacterial cells down toundetectable levels (reductions > 7 Log10). We concluded that with the
PS of appropriate doses, [Ru(bpy)2(dppn)]2+ mediated PDI inactivatedS.aureus efficiently. At the concentration of 2.5µM, bactericidal activity
was reached where the viability of bacteria fell more than 3 Log10
based on previous researches.

8553-16, Session 48553-18, Session 4

Efficacy of gallium phthalocyanine as aphotosensitizing agent in photodynamic
therapy for the treatment of cancer

Mechanistic study of apoptosis induced by
low-irradiance light delivery photodynamic
therapy

Kaminee Maduray, Durban Univ. of Technology (South Africa)

You H. Zhao, Ren Jie, Ying Gu, Chinese PLA General Hospital(China)8553-15, Session 4

Recent advances on photodynamic therapy
dosimetry (Invited Paper)
Buhong Li, Fujian Normal Univ. (China)

Photodynamic therapy (PDT), also known as photoradiation therapy
is a revolutionary treatment aimed at detecting and treating cancers
without surgery or chemotherapy. It is based on the discovery thatcertain chemicals known as photosensitizing agents or photosensitizers(e.g. porphyrins, phthalocyanines, etc.) can kill cancerous cells when
exposed to low level laser light at a specific wavelength [1]. The focus of
this study is to investigate the photodynamic effect and cellular uptakeof gallium phthalocyanine using human colorectal adenocarcinoma cells(Caco-2). Caco-2 cells will be treated with different concentrations ofgallium phthalocyanine and laser irradiated. Post-irradiated cells will
be incubated for 24 hr before measuring cell viability. Cellular uptake
studies will be performed by incubating the cells with the gallium
phthalocyanine, and lysing them into solution to measure the gallium
phthalocyanine fluorescence emission. The results showed an increasein fluorescence intensity of emission peaks at longer incubation times,
indicating a greater uptake of gallium phthalocyanine by Caco-2 cells at
24 hr in comparison to 30 min.
It is well documented that the gallium induces chromatin condensation
which is an early step of cell death (apoptosis). Therefore, thephotodynamic effect of gallium phthalocyanines will be investigatedfurther.
[1] Brown, SB, Brown, EA, and Walker I 2004, The present andfuture role of photodynamic therapy in cancer treatment, The Lancet
Oncology, vol. 5, pp. 497-504.

8553-17, Session 4

Efficient photodynamic therapy
against Staphylococcus aureus using[Ru(bpy)2(dppn)]2+, a novel cationicphotosensitizer
Yucheng Wang, Nankai Univ. (China) and Chinese PLA General

Photodynamic therapy (PDT) is an approved therapeutic procedurethat exerts cytotoxic activity towards tumour cells by irradiating
photosensitisers with light exposure to produce reactive oxygen species(ROS). In contrast to conventional PDT treatment that low-irradiancelight delivery PDT has been reported to be more effective to eradicate
tumor. Purpose: To investigate the mechanism of this phenomenon.
Experimental Design: Hela cells were co-incubated with Photofrin(5 µg/ml) in complete growth medium in the dark. After 16 h of incubation,
the cells were irradiated at 3 mW/cm2 or 30 mW/cm2 with identicallight dose(3 J/cm2). For the control group, cells were incubated in thesame medium without Photofrin or light. Cellular ROS generation was
assayed with DCF. Mitochondrial depolarization under PDT treatment
was labeled by TMRM (tetramethylrhodamine, methyl este). In order toimage single cells, the confocal laser scanning microscope system wasused.
Results: The fluorescence intensity of DCF in the cells irradiated at 3
mW/cm2 was significant higher than cells irradiated at 30 mW/cm2. The
fluorescence intensity of TMRM in the cells irradiated at 3 mW/cm2 wasdecreased quicker than the cells irradiated at 30 mW/cm2.
Conclusions: In contrast to that conventional PDT treatment that lowfluence light delivery PDT is more effective to induce ROS generationand damage mitochondria.

8553-19, Session 4

Water-soluble benzylidene cyclobutanone
dyes for two-photon excited photodynamic
therapy
Qianli Zou, Technical Institute of Physics and Chemistry (China)
and Graduate Univ. of the Chinese Academy of Sciences(China); Hongyou Zhao, Chinese PLA General Hospital (China);
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Conference 8553:
Optics in Health Care and Biomedical Optics V
Yuxia Zhao, Technical Institute of Physics and Chemistry(China); Ying Wang M.D., Ying Gu, Chinese PLA General
Hospital (China); Feipeng Wu, Technical Institute of Physics andChemistry (China)

8553-21, Session 5

Two-Photon Excited Photodynamic Therapy (TPE-PDT) is a novel
phototherapy technology, which attracts much attention in recent years
due to its advantages of deep biological tissue penetration and highlyselective targeting damage. Conventional clinical PDT drugs were usedin early TPE-PDT studies. However, their two-photon absorption (TPA)
cross-section values were too small to be suitable clinically. In last
decade, a great number of compounds with large TPA cross-section
values were reported. However, most of them are hydrophobic, can not
be used as photosensitizer directly for TPE-PDT.

Valery V. Tuchin, N.G. Chernyshevsky Saratov State Univ.
(Russian Federation) and Univ. of Oulu (Finland) and Russian
Academy of Sciences (Russian Federation)

In this study, a series of polyethylene glycol-functionalized benzylidene
cyclobutanone dyes (Q1-Q4) for TPE-PDT were synthesized. Detailed
characterization and systematic studies of these molecules, including
linear and nonlinear photophysical properties, lipid/water partition
coefficients, reactive oxygen yields, and in vitro photodynamic therapy(PDT) activities, were conducted and compared with our previously
reported cyclopentanone derivatives (B2, B3) side-by-side. All thesedyes are water-soluble and two of them (Q3, Q4) are completely
miscible with water. The singlet oxygen yields of Q1-Q4 are in the rangeof 0.76 to 0.78 in toluene, which is about three times larger than thecyclopentanone derivatives. These dyes are found to have large TPA
cross-section values, for example, 801GM for Q4 at 820nm in toluene.
All the studied dyes showed no obviously dark toxicity up to 10µM, atwhich concentrate almost all cells were killed under one-photon lightirradiation. TPE-PDT activities were also successfully demonstrated
in in vitro cell experiments using 800nm laser. Owing to the simple
synthesis route and the capability of two-photon reactive oxygen
sensitizations, we believe these new synthesized dyes will be goodcandidates for TPE-PDT applications in the future.

8553-20, Session 4

Monitoring microcirculation flow ratechanges of port wine stains after
photodynamic therapy by laser speckle
imaging
Jie Ren, You H. Zhao, Ying Gu, Chinese PLA General Hospital(China)Background and Objective: Microcirculation change is an important
aspect in the study of photodynamic therapy (PDT) damage effects.
Laser speckle imaging (LSI) is a new technology developed in recent
years for the detection of microcirculation flow rate. In this study, we
aimed to monitor the microcirculation flow rate changes of Port Winestains (PWS) after PDT by LSI.
Cases and methods: A female PWS patient with a purple erythemalocated in the right lower jaw was involved in this study. The patient wasplaced in the supine position, and remained stationary in the testingprocess. The speckle images were accessed at pre-treatment, at posttreatment 0, 5, 10, 15, 20, 25, 30 min, and at the first return visit after 2
months. Finally, the speckle images of the PWS regions and the control
regions were analyzed by the RTLBI software.
Results: The flow rate values decreased in both the PWS region andthe control region after PDT. The differential flow rate values between
the PWS region and the control region have a sharp decline at 0 min
after PDT, and then rise slowly in the 0-30 min after PDT. There was little
difference in the flow rate values at the first return visit compared to thevalues accessed at 30 min after treatment.
Conclusion: LSI can be used for monitoring the microcirculation
flow rate changes of PWS after PDT. As a specific indicator, thedifferential flow rate values have certain significance in evaluate themicrocirculation changes of the PWS regions.

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Tissue optical clearing: enhanced imaging
and therapy (Invited Paper)

The main limitations of optical diagnostics and phototherapy are the low
penetration depth of light beams and/or low image contrast, becauseof high tissue scattering. The following optical diagnostic modalities
are suffering strongly from a high scattering: Doppler and speckle
blood flow measuring techniques, optical coherence tomography(OCT), confocal microscopy, SHG imaging, multi-photon spectroscopy,
polarization imaging, and Raman spectroscopy. Optical clearing due
to reduction of tissue scattering ability is an attractive method forcontrolling of optical properties of a variety of tissues. This technology
provides many benefits for successful application of optical methods inbiomedicine.1-3 Even for optical diffusion imaging, in-depth blood flow
monitoring using diffusion wave spectroscopy, and other principally
scattering-based techniques, reduction of scattering of the upper layersof tissues also could be useful to provide more flexibility in getting
quantitative information about tissue lesions and functioning. One of the
optical clearing approaches is based on impregnation of tissue by an
immersion liquid which refractive index is higher than refractive index ofinterstitial fluid (ISF) and/or tissue dehydration (losing water).
In this paper optical clearing of different tissues will be analyzed in
the framework of receiving of more precise and valuable informationfrom reflectance spectroscopy, polarization measurements, Raman
spectroscopy, confocal microscopy, and optical coherence tomography(OCT), as well as from nonlinear spectroscopies, such as two-photon
fluorescence and second harmonic generation (SHG). In vitro, exvivo, and in vivo spectroscopic, polarization, and OCT studies ofhuman tissues will be presented. Optical clearing agents and delivery
techniques, as well as tissue enhanced permeation, will be discussed.
Some important applications of optical immersion technique indermatology, ophthalmology, gastroenterology, and some other medical
fields will be demonstrated.
References
1. V.V. Tuchin, Optical Clearing of Tissues and Blood, PM 154, SPIE
Press, Bellingham, WA, 2006.
2. V.V. Tuchin, A clear vision for laser diagnostics, IEEE J. Select. Topics
on Quantum Electronics, 13, ? 6, pp.1621-1628, 2007
3. Elina A. Genina, Alexey N. Bashkatov, and Valery V. Tuchin, Tissue
optical immersion clearing, Expert Rev. Med. Devices 7(6), 825–842(2010)

8553-22, Session 5

Advances in optical clearing of tissue in vivo
(Invited Paper)
Dan Zhu, Britton Chance Ctr. for Biomedical Photonics (China)
The optical technology has provided significant tool for molecularimaging and medical diagnosis with high sensitivity and resolution,and has been a focus of life science and engineering. However, thehigh scattering in turbid biological tissues limits the penetration ofvisible and near-infrared light in tissue, which affects its applicability
in preclinical and clinical medicine, and other life science. The tissue
Optical clearing technique based on immersion of tissues into opticalclearing agents (OCAs) with high refractive indices, hyperosmolarityand biocompatibility allows one to effectively control optical propertiesof tissues, leads to essential reduction of scattering, and therefore
enhance the depth to which light penetrates in tissue, and currently
attracts great attentions. This technique, combined with various opticaltechniques has shown a great potential for improving the capabilities of
optical imaging, diagnosis and therapeutic treatments. Especially, whentissue optical clearing technique was applied on investigating the brain

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or central nervous system, the tissue micro-structural information wereobtained with high resolution by using of microscopy imaging, whichhas produce significant breakout in neuroscience field. However, thefinal purpose of optical clearing technique is to apply in vivo animal oreven human.
During the last several years, we have focused our research intereston optical clearing of tissue in vivo, including skin and skull. In orderto develop some safe, effective and reliable optical clearing methods
to perform in vivo, non-invasive subcutaneous imaging or cortex
neuroimaging, we mainly paid attention to mechanisms of tissue opticalclearing and biocompatibility of OCAs. Firstly, we explored the physicalor physiological mechanisms, and found that higher refractive indices of
OCAs improve optical clearing efficacy as long as OCAs do not change
the structure of sample. For the in vivo skin optical clearing, there wasa noticeable concentration-dependent decrease in dermal thickness
and collagen fiber diameter, and increase in fiber regularity, which isdifferent from in vitro skin optical clearing. Secondly, we paid attention
to the dynamical function and morphology of blood vessels caused
by OCAs, the negative effect on blood vessel or skin depends on thedose of OCAs and type. Topical application of a mixture of thiazone
and the OCA can make skin transparent and improve visualizationof subcutaneous microvessels. Combined with optical imaging
technology, we will be able to improve image contrast and resolution.
The optical clearing methods could be used for non-invasive optical
diagnosis of peripheral blood vessel disease.
Recently, we developed an innovative optical clearing agent of skull
which can establish a stable transparent cranial window without
craniotomy. The preliminary investigations show that there is neither
short-term nor long-term effect on cortical blood vessel distribution.
Combining optical clearing technique of skull with laser speckle
temporal contrast analysis, we not to visualize cortical blood flow athigh resolution, which was not previously possible with the use of
OCAs alone. Post-imaging treatment with saline allowed the skull
recovery. We believe that combining the transparent cranial window
with multi-photon microscopy or other optical imaging techniques will
help to study cortex neural activity in vivo, which is very beneficial forneuroscience research.

8553-23, Session 5

Autofluorescence in single molecule
fluorescence imaging
Yanqiao Huang, Austin Tomaney, Paul Lundquist, Pacific
Biosciences (United States)
Single molecule fluorescence imaging has found broad applicationin biomedical research areas such as in situ molecule tracking,conformational study of biomolecules, and DNA sequencing. Low
light levels demanded by single-molecule observations are limited
to extremely low signal levels and the SNR requirements are quitedemanding. In many systems, autofluorescence from the optical systemand from sample substrates constitutes the dominant noise sourceand determines the fundamental SNR limitations for achieving single
molecule sensitivity. However, the optical modeling of autofluroescenceis not straightforward, and little quantitative data is available for evencommonly used optical materials.
In this manuscript we present an approach to detailed opticalsimulations of this important noise source and the ultimate SNR
resolution of a specific optical system, along with guidelines forthe design of optimal instrumentation. Specific optical designs thathave been constructed are characterized and comparisons between
measured autofluorescence levels and theory are presented. We also
propose an intrinsic metric for the evaluation of optical materials,
including the separation of bulk and surface contributions and spectral
information, and a measurement methodology to separate distinct
coefficients as they impact to system noise levels. A quantitative
comparison of commonly used optical glasses and crystals is presented
along with an analysis of the importance of sample preparation andhandling both in material characterization as well as for the construction
and maintenance of optical instrumentation maintaining single-moleculesensitivity.

8553-24, Session 5

Design of an affordable fluorescence
confocal laser scanning microscope for
medical diagnostics
Christin Bechtel, Technische Univ. Dresden (Germany); Jens
Knobbe, Heinrich Grüger, Hubert Lakner, Fraunhofer-Institut
für Photonische Mikrosysteme (Germany); Günter Huber, Univ.
Hamburg (Germany)
Confocal fluorescence microscopes are a promising imaging tool in
medical diagnostics due to their capability to selectively survey crosssections of individual layers from ‘thick’ samples. Non-invasive depth
resolved investigation of neoplastic skin disorders is one example
among other applications.
However these microscopes are at present uncommon in medical
practice. This is due to their main application area in research. The
instruments dealt with here are generally complex, stationary units andare accordingly cost-intensive.
It is for this reason, we have designed a robust and portable MEMS
based confocal fluorescence microscope with a field of view of 500µm.
This has been made possible by the integration of a 2D micro¬scanner
mirror developed at Fraunhofer IPMS. A variable acquisition depth ofcross-sectional images of the fluorescence specimen is enabled by an
integrated z-shifter.
With the use of commercially available optics an optical demonstrator
set up has been realized. To characterize and to demonstrate the abilityof this system for visualization and analysis test measurements were
performed. The resolution of the microscope is better than 228 lp/mm
determined by 1951 USAF resolution test target. Images of various
biological samples are presented and optical sectioning capabilities
are shown. A comparison of the measured with the predicted system
performance will be given.

8553-25, Session 5

Multiview hyperspectral topography of tissue
structural and functional characteristics
Shiwu Zhang, Univ. of Science and Technology of China (China)
and The Ohio State Univ. (United States); Peng Liu, Univ. of
Science and Technology of China (China); Jiwei Huang, The
Ohio State Univ. (United States); Ronald X. Xu, The Ohio State
Univ. (United States) and Univ. of Science and Technology ofChina (China)
Accurate and in vivo characterization of structural, functional, andmolecular characteristics of biological tissue will facilitate quantitative
diagnosis, therapeutic guidance, and outcome assessment in many
clinical applications, such as wound healing, cancer surgery, andorgan transplantation. However, many clinical imaging systems have
limitations and fail to provide noninvasive, real time, and quantitative
assessment of biological tissue in an operation room. To overcome
these limitations, we developed and tested a multiview hyperspectral
imaging system.
The multiview hyperspectral imaging system integrated the multiview
and the hyperspectral imaging techniques in a single portable unit. Fourplane mirrors are cohered together as a multiview reflective mirror set
with a rectangular cross section. The multiview reflective mirror set wasplaced between a hyperspectral camera and the measured biologicaltissue. For a single image acquisition task, a hyperspectral data cubewith five views was obtained. The five-view hyperspectral image
consisted of a main objective image and four reflective images. Threedimensional topography of the scene was achieved by correlating thematching pixels between the objective image and the reflective images.
Three-dimensional mapping of tissue oxygenation was achieved usinga hyperspectral oxygenation algorithm. Our multiview hyperspectral
imaging technique was under quantitative validation in a wound

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model, a tissue-simulating blood phantom, and an in vivo biologicaltissue model. Preliminary validation results have demonstrated thetechnical feasibility of using multiview hyperspectral imaging for threedimensional topography of tissue functional properties. This researchis sponsored by National Institute of Standards and Technology(60NANB10D184).

8553-26, Session 6

Recent advances in optical coherence
tomography (Invited Paper)
Zhihua Ding, Chuan Wang, Yi Shen, Tong Wu, Liangming
Huang, Lan Wu, Chixin Du, Zhejiang Univ. (China)
This paper reports our recent advances in optical coherence
tomography at Zhejiang University.
A high speed swept source OCT system is reported, where spectral
calibration is conducted by use of the phase from a Mach-Zehnderinterferometer, and full-range imaging is realized by wave-number
carrier frequency. With evenly divided phase signal, arbitrary number of
uniform sampling can be realized. Wave-number carrier frequency of thespectral interference signal is introduced by a double-pass transmissive
dispersive optical delay line. High carrier frequency in the spectralinterference signal corresponding to a distance shift is exploited toobtain full-range OCT imaging. Instantaneous coherence function is
introduced for complete description of the spectral interference signal.
The performance of the established full-range imaging system is well
above conventional one-side offset approach with increased SNR andespecially suitable for high-speed SS-OCT system.
A high speed spectral domain Doppler OCT system is reported. The
developed spectral domain Doppler OCT system is applied to monitor
cerebral blood flow velocity changes in a rat. An animal model witha cranial window is used, and by application of a drug, light, andelectric stimulations, changes in blood flow velocity of the pial artery insensory cortex are measured in real time. The results show significant
differences in blood flow velocity before and after drug administration
or light and electric stimulations, demonstrating the feasibility of DOCT
in cerebral microcirculation study. Furthermore, a method based onhigher order cross-correlation is proposed in the spectral domain
Doppler OCT system to fetch the Doppler information on flow velocity
within area under low signal-to-noise ratio (SNR). Experimental results
demonstrate that the proposed method can significantly suppress
noise, thus rendering it suitable for flow measurement under low SNR
cases. Since noise is significantly suppressed, the proposed method
is much less vulnerable to low SNR and is more reliable for qualitative
Doppler imaging.

8553-27, Session 6

Intra-operative OCT devices for clinicaltranslation (Invited Paper)
Yu Chen, Chia-Pin Liang, Jaydev Desai, Univ. of Maryland,College Park (United States); Cha-Min Tang M.D., Rao L.
Gullapalli, Univ. of Maryland School of Medicine (United States)
Stereotactic procedures that require insertion of needle-based
instruments into the brain serve important roles in a variety ofneurosurgical interventions, such as biopsy, catheterization, andelectrode placement. A fundamental limitation of these stereotactic
procedures is that they are blind procedures in that the operator does
not have real-time feedback as to what lies immediately ahead of theadvancing needle. Therefore, there is a great clinical need to navigate
the instrument safely and accurately to the targets. Towards that end,
we developed a forwarding-imaging needle-type optical coherence
tomography (OCT) probe for avoiding the hemorrhage and guiding
neurosurgical interventions. The needle probe has a thin diameter of
0.7 mm. The feasibility of vessel detection and neurosurgical guidancewere demonstrated on sheep brain in vivo and human brain ex vivo.

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In addition, we further reduced the probe size to 0.3 mm using an
optical Doppler sensing (ODS) fiber probe that can integrate withmicroelectrode recording (MER) to detect the blood vessels lying ahead
to improve the safety of this procedure. Furthermore, to overcome thefield-of-view limitation of OCT probe, we developed an MRI-compatible
OCT imaging probe for neurosurgery. MRI/OCT multi-scale imaging
integrates micro-resolution optical imaging with wide-field MRI imaging,and has potential to further improve the targeting accuracy.

8553-28, Session 6

Phantom testing of a novel endoscopic OCTProbe: a prelude to clinical in-vivo laryngeal
Use
Taran Tatla, Jing-Yin Pang, Northwick Park Hospital (United
Kingdom); Ramona C. Cernat, George M. Dobre, Paul J.
Tadrous, Adrian Bradu, Univ. of Kent (United Kingdom); Grigory
V. Gelikonov, Valentin M. Gelikonov, Institute of Applied Physics(Russian Federation); Adrian Podoleanu, Univ. of Kent (United
Kingdom)
Optical Coherence Tomography (OCT) involving low-coherence infrared light interferometry allows micron-scale image resolution, providing
tissue detail up to 2-3mm deep. A unique international collaboration,
involving otolaryngologists and experts in biomedical optics used a
1300 nm SS-OCT imaging system which incorporates a miniaturisedprobe and passed it in tandem with a flexible fibreoptic nasoendoscope
into the larynx to interrogate the characteristics of normal versus
diseased tissue. The novel OCT probe (rigid part: 15mm long, diameter
1.9mm) was designed and constructed at the Institute of Applied
Physics, Russia. The probe tip was passed into a disposable latex
endosheath (outer diameter 5.5mm, inner diameter 5.2mm), alongsidea flexible fibreoptic nasoendoscope (diameter 3.7 mm) coupled to a
USB digital camera connected to its eye-piece. An ex vivo OCT image
dataset was acquired as a baseline using a desktop 1300nm TDOCT imaging system. Here we present pre-clinical data from a novel
miniaturised OCT probe utilised for endoscopic imaging of laryngeal
mucosa. We tested the feasibility, robustness and safety of this system
on an anatomically correct manikin, which was the Trucorp Airsim
Advance Larynx. Following validation of the system ex vivo, we plan toextend the use of this assembly to a patient cohort to assess patient
tolerability, practicality, clinical efficacy and accuracy. The ability to
extract histological information from OCT imagery holds great potential
to guide surgical biopsies, direct therapy and monitor disease.

8553-30, Session 7

Anatomic correlate to the hyper-reflective
inner/outer segment band in retinal opticalcoherence tomography (Invited Paper)
Xincheng Yao, The Univ. of Alabama at Birmingham (UnitedStates)Given the excellent capability to identify morphological changes atindividual functional layers of the retina, optical coherence tomography(OCT) has increasing application in eye disease detection. Early studies
have disclosed four hyper-reflective OCT bands at the outer retina, i.e.
photoreceptor side. Anatomic sources of these four OCT bands havebeen typically attributed as follows: first (1st) band at the outer limiting
membrane (OLM); second (2nd) band at the photoreceptor inner/outer-segment (IS/OS) junction; third (3rd) band at the posterior tip of
the OS; and fourth (4th) band at the retinal pigment epithelium (RPE).
Anatomic correlates of the 2nd and 3rd bands remains controversial.
The 2nd OCT band is widely attributed to the IS/OS junction, whichcell biologists consider the connecting cilium (CC) between thesestructures. However, comparative alignment of OCT bands with ananatomically correct model of the outer retina suggested an alternative

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correlate, i.e., the IS ellipsoid, to the 2nd OCT band. This study was
to experimentally test the anatomic correlate to the 2nd OCT band.
In order to achieve sub-cellular resolution in both lateral and axial
directions, a rapid line-scan OCT (LS-OCT) was developed. The
LS-OCT combined technical merits of our recently demonstrated
electro-optic phase modulator (EOPM) based functional OCT andline-scan confocal microscopy. Quantitative comparison of histologicalimages and LS-OCT images revealed that dominant source of thesignal reported as the ‘IS/OS’ OCT band actually originates from theIS. We speculate that the IS ellipsoid, which consists of abundantmitochondria, or the CC extended into the IS may contribute to theobserved 2nd OCT band signal.

8553-31, Session 7

Imaging of coronary arteries and respiratory
airways ex vivo using micro-opticalcoherence tomography (µOCT)
Linbo Liu, Harvard Medical School (United States) and
Massachusetts General Hospital (United States); Joseph A
Gardecki, Brett E. Bouma, Guillermo J. Tearney, Massachusetts
General Hospital (United States)
Understanding pathophysiology processes in coronary arteries andrespiratory airways requires knowledge of tissue anatomy at thecellular and sub-cellular level. Unfortunately, methods for visualizing
coronary arterial wall and respiratory mucosa at high resolution arelimited. We have developed a novel imaging technique termed µOCT
which obtains images with a resolution of 2 µm ? 2 µm ? 1 µm (x, y, z)
in tissue. We used the µOCT system to image fresh human coronary
arteries prosected from explant (donor) hearts, cultured humanbronchial epithelial (HBE) cells, and freshly explanted swine tracheas.
Preliminary results show that µOCT is capable of visualizing most of
sub-cellular structures associated with coronary artery diseases (CAD)
and mucociliary clearance (MCC) in three dimensions in intact humantissues. Future development of µOCT for imaging in vivo could open up
new opportunities for studying CAD and respiratory airway diseases inhuman patients.

8553-32, Session 7

In vivo integrated photoacoustic
ophthalmoscopy, optical coherence
tomography, and scanning laser
ophthalmoscopy for retinal imaging
Wei Song, Harbin Institute of Technology (China) andNorthwestern Univ. (United States); Rui Zhang, Harbin Instituteof Technology (China); Hao F Zhang, Northwestern Univ. (UnitedStates); Qing Wei, Northwestern University (United States)
and Northwestern Univ. (United States); Wenwu Cao, Harbin
Institute of Technology (China) and The Pennsylvania State
Univ. (United States)
Photoacoustic ophthalmoscopy (PAOM) is an emerging ophthalmic
imaging technology that measures optical absorption properties of
the retina. By delivering short laser pulses onto the posterior segmentof the eye and detecting laser-induced photoacoustic (PA) signals
with an unfocused ultrasonic transducer, PAOM non-invasively
images retinal/choroidal vascular networks and retinal pigment
epithelium (RPE) melanin at a high contrast due to the strong opticalabsorption of hemoglobin and melanin. Fluorescein angiography(FA), autofluorescence-scanning laser ophthalmoscopy (AF-SLO),
and spectral-domain optical coherence tomography (SD-OCT) are
widely used in the ocular research, but they predominantly rely on
fluorescence/scattered photons from the retina. Because retinal
physiology and pathology are always associated with multiple opticalcontrasts, the integration of PAOM with the well-established ophthalmic
imaging techniques permits the complementary evaluation on theretina. We built a multimodal imaging platform of PAOM, SD-OCT, andFA for in vivo imaging of wild-type rat eyes, which revealed the opticalabsorption, optical back-scattering, and fluorescence properties in
the retina. Further, an integrated PAOM, SD-OCT, and AF-SLO wasdeveloped for imaging mice eyes because mice have more attractive
advantages of widely available genetically defined strains, wellcharacterized genome, and well-established techniques for genetic
manipulation. The multimodal capability was demonstrated by imaging
transgenic Nrl-GFP mice that express green fluorescent protein (GFP)
in photoreceptors. Our integrated ophthalmic imaging system provides
more comprehensive information of the retina, and therefore it holds
potentials for benefiting clinical diagnosis and fundamental investigationof major blinding diseases.

8553-33, Session 8

Studying the role of macrophages incirculating prostate cancer cells by in vivo
flow cytometry (Invited Paper)
Xunbin Wei, Shanghai Jiao Tong Univ. (China)
Metastasis is a very complicated multi-step process and accounts forthe low survival rate of the cancerous patients. To metastasize, themalignant cells must detach from the primary tumor and migrate tosecondary sites in the body through either blood or lymph circulation.
Macrophages appear to be directly involved in tumor progression
and metastasis, but the role of macrophages in affecting cancer
metastasis has not been fully elucidated. Here, we have utilized a novel
technique, namely in vivo flow cytometry (IVFC) to study the depletion
kinetics of circulating prostate cancer cells in mice and how depletionof macrophages by the liposome-encapsulated dichloromethylene
diphosphonate affects the depletion kinetics. Our results show thedifferent depletion kinetics of PC-3 cells between macrophage-deficientgroup and the control group. The number of circulating tumor cells(CTCs) in macrophage-deficient group decreases in a slower mannercompared to the control mice group. The differences in depletion
kinetics indicate that the absence of macrophages facilitates the stayof prostate cancer cells in the circulation. In addition, our imaging datasuggest that macrophages might be able to arrest, phagocytose anddigest PC-3 cells. Therefore, the phagocytosis may mainly contributeto the depletion kinetic differences. The study here might provide new
insights in anti-prostate cancer therapy.

8553-34, Session 8

Monitoring heart and respiratory rates atradial artery based on PPG
Cheng Wang, Univ. of Shanghai for Science and Technology(China)To develop an apparatus for simultaneous monitoring of heart andrespiratory rates using photoplethysmography (PPG) and Fast Fourier
Transform algorithm (FFT). The PPG waveform was measured at
the radial artery with an original based on diffuse reflectance mode
photoplethysmographic device. A FFT algorithm was used to extract
heart and respiratory information from the PPG waveform. The results
good agree with conventional method. The correlation coefficient ofheart rate and respiratory rate obtained using PPG waveform andconventional method, which are 0.988 and 0.976, respectively. The
PPG waveform and FFT algorithm can contribute to quicker and moreaccurate measurement of human heart rate and respiration rate. A
portable watch-like device can be made via this method and be utilized
to monitor heart and respiratory rates in hospitals or daily life care.

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Conference 8553:
Optics in Health Care and Biomedical Optics V

8553-35, Session 8

Noninvasive monitoring traumatic brain
injury based on an annular transducer array
Diwu Yang, Hunan Univ. of Technology (China)
A photoacoustic imaging system with an annular transducer array was
designed for noninvasive in vivo monitoring of traumatic mouse brain.
The annular transducer array consists of 256 elements arranged along
a 300-deg arc with a 50-mm radium of curvature, using piezocomposite
technology for high sensitivity and signal-noise-ratio. An 8-channel
data acquisition system is applied to capture the photoacoustic
signals using multiplexing and a limited- view filtered back projection
algorithm is used to reconstruct the photoacoustic images. Traumaticlesions accompanying with hemorrhage in the mouse cortical surface
were accurately mapped and a series of photoacoustic images ofmorphological changes were also obtained during rehabilitation processof a mouse brain with traumatic brain injury. Compared to other imaging
systems, the imaging system overcomes the shortcomings of the longdata acquisition time and requiring rotating transducer.

8553-36, Session 8

Simulating the demyelination of a nerve
fiber by action potential encoded second
harmonic generation
Hong-Pin D. Yang, Zhihui Luo, Xinguang Chen, Yimei Huang,
Shusen Xie, Fujian Normal Univ. (China)
Demyelination is the main underlying factor responsible for someneurological diseases. The primary clinical diagnostic methods in
identifying demyelination include magnetic resonance imaging (MRI),
analysis of cerebrospinal fluid (CSF) and visual evoked potential(VEP). However, these methods have limitations of sensitivity and/or accuracy. In this paper, we simulated the demyelination of a nerve
fiber by action potential encoded second harmonic generation (SHG),
which may greatly improve the sensitivity and accuracy. The dynamics
of action potential propagation in a multi-internode demyelinated nerve
fiber, including successive internodes and intermittent internodes was
simulated. We found that the attenuation and delay of action potential
could obviously change, while the refractory period would increase fora demyelinated never fiber. In addition, under the same demyelinatedconditions, i.e. the same thickness and number of the demyelination,
the peak of SHG signals attenuated much more along successive
injured internodes than intermittent injured internodes. Demyelination
in a nerve fiber could be revealed through the dynamics of action
potential recorded by optical SHG signals. Our study indicates that
action potential encoded SHG could be a powerful tool for examining
the demyelination induced by autoimmune diseases, or many metabolicand inflammatory disorders.

8553-37, Session 8

The diagnosis of CTCL by color image
enhancement technique
Shih-Jie Dai, Hsiang-Yuan Tan, Ta-Wei Chien, National Chung
Cheng Univ. (Taiwan); Yu-Ping Hsiao, Chung Shan Medical
Univ. (Taiwan); Hsiang-Chen Wang, National Chung Cheng Univ.
(Taiwan)Cutaneous Lymphoma is a heterogeneous group of extranodal nonHodgkin’s lymphoma, which is the most common cutaneous T-cell
lymphoma, known as the general academic with CTCL (Cutaneous
T-cell Lymphoma). Such symptoms for the majority of plaque are onlya slight redness, peeling, but some parts will have skin atrophy to forma reticular pigmentation. Some patients will be accompanied by skinsensation abnormalities, such as tingling phenomenon. In addition,
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some patients there will be local depigmentation of the skin pigment.
Sometimes, physician may be mistaken for white spot or systemic
Pityriasis alba. Recently, methods of the CTCL diagnosis are using theexcision biopsy, blood tests, and ultrasound scans. In this study, we
use multi-spectral image technology to reproduce new images of theabnormal tissues. The objects for visual perception enhancement focus
on the CTCL for coordinating with doctor`s diagnosis.

8553-38, Session 9

Identification of non-neoplastic andneoplastic gastric polyps using multiphoton
microscopy (Invited Paper)
Jianxin Chen, Shanghai Jiang, Fujian Normal Univ. (China);
Deyong Kang, Meifang Xu, Fujian Medical Univ. (China)
Gastric polyps can be broadly defined as luminal lesions projecting
above the plane of the mucosal surface. They are generally divided into
non-neoplastic and neoplastic polyps. Accurate diagnosis of neoplastic
polyps is important because of their well-known relationship withgastric cancer. Multiphoton microscopy (MPM) based on two-photon
excited fluorescence (TPEF) and second harmonic generation (SHG)
is one of the most important recent inventions in biological imaging. In
this study, we used MPM to image the microstructure of gastric polyps,
including fundic gland polyps, hyperplastic polyps, inflammatory fibroid
polyps and adenomas, then compared with gold-standard hematoxylineosin(H-E)-stained histopathology. MPM images showed that different
gastric polyps have different gland architecture and cell morphology.
Dilated, elongated or branch-like hyperplastic polyps are arranged byneck cells and columnar epithelial cells. Inflammatory fibroid polyps
are composed of small, thin-walled blood vessels surrounded by shortspindle cells. Fundic glands polyps are lined by parietal cells and chiefcells, admixed with normal glands. Gastric adenomas are generallycomposed of tubules or villi of dysplastic epithelium, which usuallyshow some degree of intestinal-type differentiation toward absorptive
cells, goblet cells, endocrine cells. Our results demonstrated that MPM
can be used to identify non-neoplastic and neoplastic gastric polyps
without the need of any staining procedure.

8553-39, Session 9

Collagen fiber spatial orientation mapping
using polarization-sensitive SHG microscopy
Vladimir A. Hovhannisyan, National Taiwan Univ. (Taiwan); PoSheng Hu, National Taiwan Univ (Taiwan); Chen-Yuan Dong,
National Taiwan Univ. (Taiwan)
Ability to characterize and quantify 3D structural organization oftissue fibers using non-invasive optical microscopy is important for
the functional characterization of the extent of disease progression.
Polarization dependence of the second harmonic signal from opticallynonlinear tissues and other noncentrosymmetric materials provides
information on characteristic orientations and degree of structuralorganization not available from intensity measurements alone. However,azimuth (or lateral) angle of collagen fiber orientation was the onlyorientation parameter quantified in previous studies. Here we suggest
a simple approach for determining both the azimuth and elevation
angles, and spatial orientation mapping of second harmonic generated
structures.
Using dependences of the effective second-order nonlinear
susceptibilities for producing SHG signal components with parallel andperpendicular polarizations on the azimuth (b) and elevation (d) angles[1], the expressions for b and d are derived [2], and pixel-resolution
mapping of collagen fiber spatial orientation in tendon, cornea, and skin
was demonstrated using SHG polarization-resolved microscopy. The
new approach may be used for analyzing of biological tissues in vivo.
Spatial orientation mapping method provides additional information
about fiber organization, and may be incorporated into nonlinear optical

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imaging systems.
[1] A. Erikson, J. Örtegren, T. Hompland, C. de Lange Davies, and M.
Lindgren, J. Biomed. Opt. 12, 044002 (2007).
[2] V. A. Hovhannisyan, P.S. Hu, H.-Y. Tan, S.J. Chen, C.Y. Dong. J.
Biophotonics 5, (2012).

8553-40, Session 9

Measuring intracellular calcium dynamics
of HeLa cells exposed to nitric oxide byfluorescence microplate reader
Yimei Huang, Jiangxu Chen, Hongqin Yang, Liqin Zheng, Yuhua
Wang, Hui Li, Shusen Xie, Fujian Normal Univ. (China)
Nitric oxide (NO) has been reported to promote or inhibit cancer cellproliferation and metastasis. NO appears to have an effect on inducing
calcium transients, which participates in essential cellular signaling in
the physiological and pathological processes. Our work was intended to
study the effects of exogenous NO on intracellular calcium dynamics of
HeLa cells measured by a fluorescence microplate reader with Fluo-3, acalcium fluorescent indicator. Results showed that after NO donor was
injected into the wells, intracellular Ca2+ fluorescence intensity changed
significantly comparing to that of the control group. Moreover, thecalcium transients activated by NO were likely to be due to extracellular
calcium influx. These would be helpful to further recognize the roles ofNO involving in cancer cell proliferation and metastasis.

Jen, Hsiang-Chen Wang, National Chung Cheng Univ. (Taiwan)
Bladder cancer is one of the common malignant tumors of the urinary
system. One of them is transitional cell carcinoma, accounting for
more than 90% of all bladder cancer. In this study, the detection of thedegrees of transitional cell carcinoma was demonstrated by multispectral image technique. The spectral difference with the degree of the
bladder cancer was discussed. For more exactly verify the degree ofthe bladder cancer, the Raman spectroscopy of various bladder cancer
was measured. Finally, the different degrees of the bladder cancer will
be mark and display through color image reproduction.

8553-43, Session 10

Optical methods for knee osteoarthritis
detection
Yanping Chen, Chunbin Li, Xiong Ma, Xiamen Univ. (China)
Osteoarthritis is one of the most common diseases nowadays. One
with serious damage of osteoarthritis would get disabled of joint, andlife quality decreased. Optical methods for knee osteoarthritis detection
were reviewed in this paper. Firstly, the advantages and disadvantagesof some common imaging diagnostic techniques, such as X-ray, CT
and MRI, were briefly summarized. Then three kinds of typical optic
methods for the detection were introduced emphatically, which arecoherence tomography (OCT), diffuse optical tomography (DOT) andphotoacoustic tomography (PAT). After the introductions of somefeatures of these three optical imaging methods on OA detection, thispaper briefly forecasts their application prospects in early OA detection.

8553-41, Session 9Morphological and metabolic changes ofcultured DRG neurons induced by adenosineusing confocal microscopy[confocal laser
scanning microscopy] imaging
Liqin Zheng, Jiangxu Chen, Yuhua Wang, Yimei Huang,
Hongqin Yang, Yanding Zhang, Shusen Xie, Fujian Normal Univ.
(China)Adenosine exerts multiple effects on pain transmission. However,
the mechanism is still controversial. This study was performed touse confocal microscopy to evaluate whether adenosine could affectdorsal root ganglia (DRG) neurons in vitro and test which P1 receptor
mediate[mediates]s the effect of adenosine on DRG neurons. Afteradding adenosine with different concentration, we compared themorphological changes of cultured DRG neurons by quantifying theaxonal length, soma size and the ratio of nucleus and cytoplasm.
And the metabolic changes were also in comparison by the real time
imaging of ATP (NAD(P)H, FAD), calcium and mitochondria membranepotential using confocal microscopy after adding adenosine withdifferent concentration. The results showed that the effect of 500µM
adenosine on the morphological and metabolic changes of DRG
neurons was more significant than others. Furthermore, four different
P1 receptor antagonists were used to study which receptor mediatedthe influences of adenosine on the cultured DRG neurons. All theantagonists, except adenosine A1 receptor antagonist (DPCPX), had
no or little effect on the DRG neurons. The above studies demonstrated
that adenosine may be involved in the signal transmission on thesensory neurons and the adenosine A1 receptor mediated thetransmission.

8553-44, Session 10

Noninvasive screening for diabetes using
skin fluorescence
Yikun Wang, Anhui Institute of Optics and Fine Mechanics(China); Shandong Ye, Chengsong Ye, Anhui Medical Univ.
(China); Yuanzhi Zhang, Fei Li, Anhui Institute of Optics andFine Mechanics (China); Gong Zhang, Univ. of Manitoba(Canada); Ling Zhu, Yong Liu, Anhui Institute of Optics and Fine
Mechanics (China)
Advanced glycation end-products (AGEs) are biochemical end-products
of non-enzymatic glycation. The accumulation of AGEs in tissue has
been implicated in the progression of diabetes mellitus and related
complications. Some AGEs fluoresce and accumulation of AGEs intissue can be assessed noninvasively through optical spectroscopy.
A portable device for noninvasive assessment of AGEs using skinfluorescence and reflectance spectrum has been developed, andnoninvasive screening for diabetes has been evaluated with it. Results
indicated that the noninvasive technology assessing skin AGEs is moresensitive at screening diabetes than either fasting plasma glucose or
glycated hemoglobin A1C. These results suggest that noninvasive
assessment of skin AGEs may be an effective tool to identify individuals
with diabetes mellitus. Besides, the noninvasive technology yields
immediate results, and since measuring skin fluorescence andreflectance spectrum require no blood draws or subjects fasting,the developed device may be well suited for diabetes opportunistic
screening.

8553-45, Session 108553-42, Session 10

Novel optical detection of bladder cancer
cells

Nonlinear optical imaging characteristics ofcolonic adenocarcinoma using multiphoton
microscopy

Jhe-Ming Yang, Tsung-Chih Lin, Ching-Te Huang, Chun-Ping

Nenrong Liu, Rong Chen, Jianxin Chen, Fujian Normal Univ.

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Conference 8553:
Optics in Health Care and Biomedical Optics V(China)8553-63, Poster Session

Colorectal cancer is the third most common malignancy, and themost common colorectal cancer cell type is adenocarcinoma which
accounts for 95% of cases. Early detection is important. Multiphoton
microscopy (MPM) is a noninvasive optical method with highresolution and high sensitivity, can obtain detailed microstructures of
biotissues at submolecular level. In this study, MPM is used to image
microstructure varieties of human colonic mucosa and submucosa
with adenocarcinoma. The distortion of glands, loss of collagen, anddistribution of cancer cells in cancerous tissues are clearly monitored,
which are tightly relevant to the clinical pathology of early colorectal
cancer. The morphological and pathological differences between normal
and cancerous can be effectively distinguished using the MPM. And
some parameters, such as gland configuration, SHG/TPEF intensity
ratio, and collagen orientation and so on, should serve the indicators ofearly colorectal cancer. The exploratory results show that it’s potential
for the development of multiphoton mini-endoscopy in real-time early
diagnosis of colorectal cancer.

A simulation method of polarizationsensitive optical coherence tomography
based on a polarization-sensitive Monte
Carlo program and a sphere cylinder
birefringence model

8553-46, Session 10

Molecular application of spectral photoacoustic imaging in pancreatic cancer
pathology
Minalini Lakshman, Clinton W. Hupple, VisualSonics Inc.
(Canada); Ines Lohse, Ontario Cancer Institute (Canada) andCampbell Family Cancer Research Institute (Canada); David
W. Hedley, Ontario Cancer Institute (Canada) and Campbell
Family Cancer Research Institute (Canada) and Univ. of Toronto(Canada); Andrew Needles, Catherine Theodoropoulos,
VisualSonics Inc. (Canada)
Spectral imaging is an advanced photo-acoustic (PA) mode that candiscern optical absorption of contrast agent(s) in the tissue microenvironment. This advancement is made possible by precise control of
optical wavelength using a tunable pulsed laser, ranging from 680-970
nm. Differential optical absorption of blood oxygenation states makes
spectral imaging of hemoglobin ideal to investigate remodeling of thetumor microenvironment- a molecular change that renders resistance tostandard cancer treatment.
Approach: Photo-acoustic imaging was performed on the Vevo®
LAZR system (VisualSonics) at 5-20 Hz. Deep abdominal imaging was
accomplished with a LZ250D probe at a center frequency of 21MHz
and an axial resolution of 75 µm. The tumor model was generated in
an immune compromised mouse by surgical implantation of primarypatient derived tumors, in the pancreas.
Results: Spectral imaging for oxygen saturation at 750 nm and 850 nm
characterized this tumor with a poorly oxygenated core surrounded
by a well oxygenated periphery. Multispectral imaging identified a
sub region in the core with a four-fold signal exclusively at 750 and
800 nm. A co-registered 2D image of this region was shown to beechogenic and calcification was suspected. Perfusion imaging with
contrast enhanced ultrasound using microbubbles (Vevo MicroMarker®
contrast agents, VisualSonics) identified functional vessels towards
this sub region. Histology confirmed calcification and vascularizationin the tumor core. Taken together, non-invasive characterization of
the tumor microenvironment using photo-acoustics rendered spectral
imaging a sensitive tool to monitor molecular changes representative of
progression of pancreatic cancer that kills within 6 months of diagnosis.

Dongsheng Chen, Nan Zeng, Celong Liu, Hui Ma, Graduate
School at Shenzhen, Tsinghua Univ. (China)
In this paper, we present a new method to simulate the signal ofpolarization-sensitive optical coherence tomography (PS-OCT), by using
a sphere cylinder birefringence tissue model and a polarization sensitive
Monte Carlo program developed by our lab. Using the program andthe model, we can simulate complicated tissue containing anisotropic
microstructures and various polarization imaging and measurement
systems. In this simulation program, the detecting area and angle range
and the scattering times of the photons are three main conditions used
to screen out the photons contributing to various imaging methods.
We study the effects of these three factors on the signals of PS-OCT
through simulation using our program, and simulation results show thatthe scattering times of the photon is a key factor to simulate a rightPS-OCT signal, and detecting area and angle range are less importantbut necessary. By comparison of our simulation with Extended Huygens
Fresnel (EHF) method and experimental results, we set a proper
screening regularity of PS-OCT photons. Meanwhile, we also makesome research on the influence of two anisotropic sources in tissue
on PS-OCT imaging: cylindrical scatters and tissue birefringence. In
previous work, we have reported that fiber structure and birefringenceeffect in tissue caused by molecular inherent characters can generate
optical anisotropy, and experiments and simulations of PS-OCT showthat the retardation measured by PS-OCT comes from birefringenceeffect. In this paper, we explain further the regularities of anisotropic
structure characterization by PS-OCT, through comparison of thedifferent imaging regularities of anisotropic sphere scatters andanisotropic cylindrical scatters.

8553-73, Poster Session

Temperature changes in the pulp chamber
during cavity preparation with Er:YAG laser
Xianzeng Zhang, Shusen Xie, Fujian Normal Univ. (China)
To examine the temperature changes in the pulp chamber during
cavity preparation with the Er:YAG laser (2940 nm), a total 20 intact
molars teeth were divided into 5 groups for cavity preparation withdifferent radiant exposures at 4Hz and 8Hz with and without water
spray. the total time of irradiation was 40 sec. Cooling was done witha water spray (3 mL/min). It showed that the temperature in the pulp
increased with the increasing of radiant exposure and pulse repetition
rate. The highest rise of temperature in the pulp was achieved with
20 J/cm2 and 8 Hz(19.83°C). For all the sample without water spray,
the rise of temperature was exceed 5°C. In contrast, with water spray,
the temperature rise in the pulp can be firmly controlled under 1°C.
The highest rise of temperature appeared at 8Hz and 20J/cm2. It also
indicated that the influence of energy on temperature increase wasstronger than that of frequency

8553-79, Poster Session

Second harmonic generation imaging of skinwound healing and scarring in a rabbit ear
model
Yiyan Tang, Affiliated First Hospital Fujian Medical Univ. (China);
Xiaoqin Zhu, Fujian Normal Univ. (China); Shuyuan Xiong, Fujian

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Medical Univ. (China); Jianxin Chen, Fujian Normal Univ. (China)
Skin wound healing and scarring in rabbit ears was examined bysecond harmonic generation (SHG) microscopy. Rabbit ear woundmodel was created by punching from the ventral surface with removalof epidermis, dermis and perichondrium. The samples were collected
weekly, and cut into 100 um thickness sections for SHG imaging. SHG
imaging system was operated at 810 nm, producing SHG signals at half
the excitation wavelength 405 nm. A Plan-Neofluar objective (?40 and
NA=0.75) was employed for focusing the excitation beam into tissue
samples and was also used to collect the backscattered intrinsic SHG
signals. Our results showed apparent difference in collagen content
and microstructure at various wound healing and scarring time points.
It suggested that SHG signals from collagen can serve as a good
indicator for characterization of wound status. With the advancementon miniaturization, microscopy based on SHG will become a valuable
tool for monitoring the wound healing and scarring in vivo, and help to
guide the improvement of scar appearance with appropriate and subtle
modulation during wound healing based on better understanding ofscarring response mechanism.

8553-80, Poster Session

Study of human plasma protein fraction by
combining membrane electrophoresis withsurface-enhanced Raman spectroscopy
Jing Wang, Juqiang Lin, Zufang Huang, Fujian Normal Univ.
(China); Yonghong Shao, Shenzhen Univ. (China); Peng Lu, Wei
Shi, Jinyong Lin, Rong Chen, Fujian Normal Univ. (China)
Surface-enhanced Raman spectroscopy (SERS) is emerging as a
powerful method in the characterization of biological materials. Recently
SERS was successfully applied for blood plasma analysis and obtained
good results. However, the effect of blood types on these studies was
not discussed adequately in previous reports. In this study, membraneelectrophoresis based SERS method was carried out to study theseeffects. The plasma proteins were firstly purified by membraneelectrophoresis and then mixed with silver colloids to perform SERS
spectral analysis. We use this method to analyze the blood plasmaof normal samples and cancerous samples, where the cancerous
samples were obtained from patients (n = 28) with pathologicallyconfirmed gastric cancer and the normal samples were obtained fromhealthy volunteers (n = 48). Principal component analysis (PCA) was
then performed on the spectra of these two groups, respectively.
PCA plots calculated from these two groups have similar results andreveal that the data points as a representative of different blood types
clustered together in a small region, meaning that these plots can not
be distinguished by any clear delineation between different groups. It’s
more likely that the expressions of alleles which are relative to blood
types do not result in distinct differences in the SERS spectra. Thesesuggest that blood types have little effect on the SERS analysis ofblood plasma.

8553-81, Poster Session

Detection of recombinant membrane
receptor protein expression in living
transgenic HEK293 cells using Raman
spectroscopy
Juqiang Lin, Jing Wang, Zufang Huang, Wei Shi, Jinyong Lin,
Peng Lu, Rong Chen, Fujian Normal Univ. (China)
Raman spectroscopy can be used for noninvasively measuringchanges in cellular activity in single living cells without further labeling/
modification or denaturing of the target. G-protein coupled receptor 120(GPR120) is an orphan G-protein-coupled receptor playing functions
as a sensor for dietary fat in the gustatory and digestive systems. In
this study, we recorded Raman spectra of single HEK293 cells at thedifferent induction concentration during the G-protein coupled receptor
120 (GPR120) proteins in transformed HEK293 cells were induced byaddition of doxycycline. We found that the intensity of the GPR120
protein-associated spectra from single HEK293 cells is depend on thedose of inducer and increased accordingly, which correlates with theaccumulation of GPR120 proteins inside the cells. Moreover, principal
components analysis (PCA) of the spectra revealed that the data points
for the different treatments of HEK293-GPR120 cells form distinct,
completely separated clusters with the receiver operating characteristic(ROC) area of 1, while for the HEK293 cells form a little overlap clusters
with the ROC area of 0.815. These findings demonstrated that Raman
spectroscopy combined with mathematical methods has sufficientsensitivity for real-time, noninvasive, and quantitative monitoring of
biological processes in single living cells.

8553-82, Poster Session

Surface-enhanced Raman spectroscopy
study of radix astragali based on soxhlet
extractor
Peng Lu, Juqiang Lin, Nengrong Liu, Fujian Normal Univ.
(China); Yonghong Shao, Shenzhen Univ. (China); Jing Wang,
Wei Shi, Jinyong Lin, Rong Chen, Fujian Normal Univ. (China)
Radix Astragali, one of the most important Chinese traditional medicine,is sweet in taste with a slightly warm property in nature and manifests
its the therapeutic actions in the spleen and lung meridians. But inherbal medicine market, counterfeits are very popular which are not
only useless to sufferers, but also may cause chronic toxicity. So,
it is very important for us to distinguish and identify Radix Astragali
though one relatively more precise and quicker quality analysis way.
Among other things, high sensitivity, flexibility, and “fingerprints”
sensing capability make Surface-enhanced Raman Spectroscopy(SERS) a very powerful method for the characterization of Radix
Astragali. In this study, Radix Astragali were firstly extracted throughcontinuous circumfluence extraction method and then mixed with silver
nanoparticles for SERS detection. Among the Raman spectrum wehave obtained, most Raman bands due to Radix Astragali extraction
solution are found at 440~520cm-1 and 950~1490 cm-1. Importantly,
two main peaks of Radix Astragali spectrum are found at 729 and 1327
cm-1 which belong to the vibration bands of adenine and C(6)-H2
respectively. The preliminary results show that SERS combining with
continuous circumfluence extraction method may be a direct, accurate
and rapid detection method of Radix Astragali.

8553-83, Poster Session

Photo-induced electron transfer between
dendritic zinc(II) phthalocyanine bearing
carboxylic terminal groups and methyl
viologenYuhua Wang, Jiangxu Chen, Lishan Huang, Shusen Xie,
Hongqin Yang, Yiru Peng, Fujian Normal Univ. (China)
Dendritic phthalocyanines have been emerged as a new kind ofpromising biomaterial for biological imaging, since they exhibit excellent
photophysical properties, such as a large absorption cross-section, redfluorescence emission and photosensitizing properties. In this study,
the intermolecular electron transfer between carboxylic dendritic zinc(II)phthalocyanine bearing carboxylic terminal groups: tetra–{3,5-di-[3,5-di(4-carboxylic benzyloxy) benzyloxy] benzyloxy} zinc(II) phthalocyanine(G1-Znpc(COOH)16) and methyl viologens(MV2+) was studied bysteady-state fluorescence and UV/Vis spectroscopy. The effect ofdifferent concentrations of MV2+ on intermolecular electron transfer
was investigated. The results show that the fluorescence emissionof this dendritic phthalocyanine could be greatly quenched with anincreasing amount of MV2+ upon excitation at 610 nm. The SternVolmer constant(Ksv) of electron transfer is 0.792?103(L•mol -1). The

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Conference 8553:
Optics in Health Care and Biomedical Optics V
quenching coefficient Kq is 1.61?1011(L•mol-1•S-1), which is higher
than the normal value for dynamic quenching. This indicates that thefluorescence quenching of this dendritic phthalocyanine by MV2+ ismainly through a static quenching mechanism. Our study suggests that
this novel dendritic phthalocyanine is an effective new electron donor
and transmission complex and could be used as a potential biosensor
conjugated with suitable fluorescence quencher.

8553-84, Poster Session

Cutaneous pain and threshold induced by
1.32um laser stimulus with different pulses
duration
Jiarui Wang, Zai-fu Yang, Beijing Institute of Radiation Medicine(China); Guang yuan Yu, Chinese PLA General Hospital (China)
To study cutaneous pain and detection threshold induced by 1.32?mlaser stimulus in human. The skin of lateral margin of forearm wasirradiated by a 1.32?m Nd: YAP laser. This study was performed with
3 healthy adult volunteers.The energy of each pulse and whether the
subjects felt a painful sensation after each stimulus were recorded.
The pain threshold was defined as the laser dose at which the subjects
reported a painful sensation to 50% of stimulus deliveries. The pain
thresholds were determined under 3 different pulse duration. The
stimulus evoked two kinds of perceptions simultaneously?one of which
was thermal sensation and the other was pinprick sensation. As a result
the pain thresholds were determined to be 4.0mJ/mm2, 5.4mJ/mm2
and 5.03mJ/mm2 respectively under the stimulating condition of 4.0mm
beam diameter and 8ms, 0.1s and 1s pulse duration. The thresholdof cutaneous pain elicited by1.32?m laser stimulus does not change
significantly with increasing pulse duration when the exposure time in
the range of 8ms~1s.

8553-85, Poster Session

Distinction of gastric cancer tissue based on
surface-enhanced Raman spectroscopy
Jun Ma, Hanjing Zhou, Longjing Gong, Shu Liu, Zhenghua
Zhou, Ocean Univ. of China (China); Weizheng Mao, Qingdao
Municipal Hospital (East) (China); Ronger Zheng, Ocean Univ. ofChina (China)
Gastric cancer is one of the most common malignant tumors with highrecurrence rate and mortality rate in China. This study aimed to evaluate
the dia gnostic capability of Surface-enhanced Raman spectroscopy(SERS) based on gold colloids for distinguishing gastri c tissues. Goldcolloids were directly mixed with the supernatant of homogenizedtissues to heighten the Raman signal of various biomolecule. A total of
56 samples were collected from normal (30) and cancer (26). Raman
spectra were obtained with a 785nm excitation in the range of 600-1800
cm-1. Significant spectral differences in SERS mainly belong to nucleic
acid, proteins and lipids, particularly in the range of 653, 726, 828, 963,
1004, 1032, 1088, 1130, 1243, 1369, 1474, 1596, 1723 cm-1. PCALDA algorithms with leave-one-patient -out cross validation yielded
diagnostic sensitivities of 90% (27/30), specificities of 88.5% (23/ 26),
and accuracy of 89.3% (50/56), for classification of normal and cancer
tissues. The receiver operating characteristic (ROC) surface is 0.917,
illustrating the diagnostic utility of SERS together with PCA-LDA to
identify gastric cancer from normal tissue. This work demonstrated the
SERS techniques can be useful for gastric cancer detection, and it isalso a potential technique for accurately identifying cancerous tumor,
which is of considerable clinical importance to real-time diagnosis.

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8553-86, Poster Session

Error analysis of image acquisition by
moving objective lens
Hongxia Xie, Hua Chen, Guangxi Univ. (China); Yi Cai, Fengjuan
Yang, Guangxi University (China)
Abstract: In the digital confocal microscopy technology, voltage
ceramic is used to drive axial moving of objective lens to collectimage slices, which is simple and flexible, easy to control and will geta large precision. But as a result of the movement, the corresponding
parameters of the system like magnification and numerical aperture,even the point spread function changes, which will bring error to theimage restoration.
According to the principle of optical imaging, we obtained that with themoving of the objective lens, the magnification and numerical aperturechanged a little, and the PSFs of different positions were very similar,
for example, look at the central value of the PSFs, compared withthat of the initial PSF when the lens did not start to move, the biggest
relative rate of change is 1.86E-5. While MSE is the mean square errorof those PSFs and the initial PSF, and the biggest MSE is 4.99E-09, allof the differences are very small.
In the simulation experiment, it can be found that the restoration resultof image slices collected by moving objective lens is very close to therestoration result of image slices collected by moving the biologic cellon the loading platform, and the image clarity were both significantly
improved. So, using the initial PSF to restore the image slices collectedin these two ways, the difference is quite small.
Therefore, all of the results above can verify the feasibility of moving
lens to collect image slices.

8553-87, Poster Session

Reverse propagation properties of lightwave in tapered micro-nano fiber for cellendoscopy
Deshan Zhou, Jingang Zhong, Jinan Univ. (China)
Over the past decade, as the progress of manufacturing technology andbiological sensors, micro-nano optical fiber makes living cell monitoring
possible. Due to its unique optical propagation feature and sharp tip,
tapered micro-nano optical fiber is often used as probe to penetrate
into cell for internal detection. The tiny size also can greatly reduce thedamage to the cell.
Lately, an American scientist and his research team have further
developed this probing technique and put forward a kind of endoscopeused for single-cell internal structure. However, this “endoscope” only
leads the exciting light into cell membrane through optical fiber, which
is different form the traditional endoscope. If we can reversely export
optical signal from the tapered fiber, it will contribute to confirm theposition of the fluorescent labels more accurately. Consequently, it isnecessary to discuss the reverse propagation of optical wave in tapered
micro-nano optical fiber.
In this paper, we use Finite Difference Time Domain?FDTD) algorithm
to simulate the propagation of light wave back and forward in fiber
taper, respectively. The results indicate that most of the light is still incore when reverse propagation. At the same time, in the subsequent
experiment the conclusion is further proved. Based on this feature, thelight signal in living cell can be easily guided out and the real meaning“endoscopic” for cell detection would be realized.

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8553-88, Poster Session

Diiblock compolymer micelle deliver
substituted aluminum phthalocyanine forenhancement intracellular photodynamic
Zhe Chen, Fujian Normal Univ. (China)
Phthalocyanines (Pcs) and their substituted derivatives had been
intensively investigated as the second generation photosensitizers
for photodynamic therapy (PDT) of malignant cancer or or maculardegeneration. The solubility and aggregation of Pc played importantroles on the in vitro distribution and efficiency to generate singlet
oxygen. By introducing amphiphilic long spacer chains substituted
groups in the periphery of Pc ring, we hope to improve the solubility inorganic solvent, inhibit the self-aggregation, and extend the reactive
scope of interaction with proteins of this Pc. In this paper,A novel
tetra-carboxylaminohexanoicsulfonyl aluminium phthalocyanine 1 wassynthesized. Its structure was characterized by elemental analysis, IR,
1H NMR and MS. Polyion micelle (PIC) between the 1 and amphiphilic
triblock copolymer poly(L-lysin)- block-poly(ethylene glycol) (PLL-bPEG) was formed via an electrostatic interaction between the positively
charged poly(L-lysin)(PLL) segment and negatively charged peripheryof the 4 . Atom force microscopy (AFM) showed that 4-loaded PIC
formed a spherical nanocarrier micelle with approximately 100 nm indiameter. The fluorescence intensity and lifetime of 4-loaded PIC weresignificantly enhanced by the incorporation 1 into PIC nanocarrier. The
time-dependent intracellular uptake amount and in vitro photodynamic
photocytotoxicity of the 1 within the nanocarrier were drastically
improved compared with the 1.

8553-89, Poster Session

Polyion complex micelles incorporating poly(aryl benzyl ether) dendritic phthalocyanine:
effective photosensitizers for enhanced
photodynamic therapy
Kuizhi Chen, Sining Zhen, Ming Yu, Yiru Peng, Fujian Normal
Univ. (China)
Photodynamic therapy(PDT) is an effective method for treatment ofseveral diseases, including choroidal neovascularization, CNV) andsolid tumors. Creating new PSs or their formulation plays a crucial rolein the development of PDT. Among the various photosentizers (PSs)
investigated, phthalocyanine have been found to be highly promising.
Recently, phthalocyanines and their metal complexes encapsulated into
the interior core of dendrimer bearing hydrophilic surface groups havebeen prepared and reported on their prominent nature on high aqueous
solubility, avoiding aggregation as well as interesting photophysicalproperties. In order to obtain higher PDT efficacy, the selective deliveryof PSs to the target tissue was also very necessary. Amphiphilic triblock
copolymer PLL-b-PEG-b-PLL had gained increased interest, due to its
small size, thermodynamic and kinetic stability in vivo, higher drugloading capacity and good biocompatibility.
In this paper, a new series of phthalocyanines zinc (II) carrying four poly(aryl benzyl ether) dendritic substituents (Gn= n-generation dendrimer,
n=1-2) with carboxylic acid functionalities, and polyion complexes(PICs), which is formed via an electrostatic interaction between thenegatively charged periphery of anionic dendritic phthalocyanine
zinc (II) and positively charged poly(L-lysin) (PLL) segment of triblock
copolymer poly(L-lysin)- block-poly(ethylene glycol)-block-poly(L-lysin),
were prepared for use as effective photosensitizers for photodynamic
therapy.
Atom force microscopy (AFM) and transmission electron microscopy(TEM) showed that dendritic phthalocyanines formed core-shell –typenanoparticles with a relatively high polydisperisty. The photophysicalcharacteristics of dendrtic phthalocyanines and their corresponding
micelles were strongly depend on the generation of photosensitizers.
Electrostatic assembly resulted in a red-shift of the Q band of thephthalocyanine core, reduced fluorescence intensity and prolonged
fluorescence lifetime. The incorporation of dendrimer phthalocyanines
into PIC nanocarriers led to an appreciable increase in time-dependent
intracellular uptake amount , yet inversely correlated with thegeneration . Alternatively, the in vitro photocytotoxicity of dendrimer
phthalocyanines within the nanocarriers increased with an increase in
the generation despite a decrease in the cellular uptake.

8553-90, Poster Session

Ultra-long scan depth optical coherence
tomography for imaging the anterior
segment of human eye
Dexi Zhu, Meixiao Shen, Ming Li, Wenzhou Medical College(China)Most people over 45 years old had to face to the common healthproblem of presbyopia, which reduce the ability of accommodation.
The mechanism of accommodation has not been clarified yet because
the modality of anterior segment of eyes can’t be precisely monitored
during accommodation. Optical coherence tomography (OCT) is a low
coherence interferometric imaging technology and widely applied in
ophthalmology for the features of high speed, high resolution and noninvasive to eye. But the scan depth of current OCT is limited (less than
5 mm), causing it can’t been used in accommodation research. In thispaper, we developed a novel spectral domain OCT with ultra-long scan
depth for imaging the entire anterior segment of human eye. A scan
depth of 11 mm and an axial resolution of 10 um are achieved basedon the specially designed spectrometer of OCT system, thus the entire
anterior segment from front surface of cornea to the posterior surfaceof crystalline lens is included in one picture. In order to compensate thedrop of signal to noise ratio (SNR) through the OCT image, the opticaldistance in reference arm was adjustable to acquire two images withdisplacement of zero delay line. These images were overlapped finallyto generate one picture with no SNR drop. We demonstrated that using
this ultra-long scan depth OCT, the changes of anterior segment wereclearly observed in vivo during the eye accommodation.

8553-91, Poster Session

A high-density localization of active
molecules for super-resolution microscopy
Xin Liu, Qimei Liao, Gang Li, Junyan Rong, Hongbing Lu, Fourth
Military Medical Univ. (China)
The super-resolution microscopy techniques based on single-moleculeswitching, e.g., stochastic optical reconstruction microscopy (STORM)
or (fluorescence) photoactivated localization microscopy ((f)PALM),
can achieve 20-30 nm spatial resolution, which provide a powerful
way to understand molecular processes in live cells. However, toobtain high spatial resolution, the super-resolution microscopy requires
accumulating enough single-molecule switching events, which need
the long imaging time. As a result, the low imaging speed limits theuse of the technique in live cell imaging, especially in dynamic live cell
imaging. To improve the temporal resolution without sacrificing the
spatial resolution, an efficient approach is to increase the density ofactivated fluorophores in each image frame. However, the high-densityof activated fluorophores in each frame leads to them overlap eachother. As a result, the existing single-molecule localization method
is difficult to solve the problem. To overcome the limit, in this paper,
based on the compressed sensing theory, we propose a high-density
localization method, which is implemented by minimizing the total
variation (TV) of image frame. To evaluate the performance of the
proposed method, the numerical simulations are performed. The results
demonstrate that compared with the previous reported localization
method, the proposed method greatly can reduce the imaging time,
while keeping a similar imaging quality.

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Conference 8553:
Optics in Health Care and Biomedical Optics V

8553-92, Poster Session

8553-94, Poster Session

Observation of water diffusion in human skinwith optical coherence tomography

Fractional laser microablation as anenhancer for skin optical clearing

Feng-Yu Chang, Chih-He Yang, Kung-Min Lin, Chang Gung
Univ. (Taiwan); Chih-Hsun Yang M.D., Chang Gung Memorial
Hospital (Taiwan); Yuan Ouyang, Meng-Tsan Tsai, Chang Gung
Univ. (Taiwan)

Ekaterina A. Kolesnikova, Darya Tuchina, Elina A. Genina,
Leonid E. Dolotov, Alexey N. Bashkatov, N.G. Chernyshevsky
Saratov State Univ. (Russian Federation); Valery V. Tuchin, N.G.
Chernyshevsky Saratov State Univ. (Russian Federation) andInstitute of Precise Mechanics and Control (Russian Federation)and Univ. of Oulu (Finland)

Optical coherence tomography (OCT) has been widely used forbiomedical applications due to noninvasive, depth-resolves, andhigh imaging speed natures. In this study, a swept-source OCT(SS-OCT) is used for dermatology studies. Here, time-resolved OCT
images of the water diffusion process in the skin that illustrate thechanges in the attenuation coefficient of the skin due to the increased
water concentration are presented. In our experiments, the water
concentration in the skin was increased by soaking the hand in water,
and the same region of the index fingertip was scanned and measured
with the OCT system and a commercial moisture monitor every 3
min. To quantitatively analyze the process of water diffusion and theincreased water concentration detected by OCT, the attenuation
coefficients of the skin, including the epidermis and dermis layers, were
evaluated based on the Beer-Lambert law. Based on the Beer-Lambertlaw, the attenuation coefficients of the water concentration in the skin’s
epidermis and dermis layers can be evaluated during water diffusion.
Furthermore, the evaluated attenuation coefficients were compared withthe measurements by using the commercial moisture monitor. From
the results, the evaluated attenuation coefficients show the same trendwith the measured moisture from the commercial product when theskin was soaked into the water. In contrast to the measured results ofthe commercial moisture monitor, OCT can provide three-dimensional
structural images of the skin and characterize its optical properties,
which together can be used to observe morphological changes andquantitatively evaluate the water concentration in different skin layers.

8553-93, Poster Session

Quadratic trianqular element for diffuse
optical tomography
Xuanxuan Zhang, Yong Deng, Jun Xu, Zhaoyang Luo,
Hui Gong, Qingming Luo, Huazhong Univ. of Science andTechnology (China)
The forward problem of Diffuse optical tomography (DOT) can be
described by diffuse equation generally which is an approximation of
Boltzmann transport equation at the situation of high scattering andlow absorption . Diffuse equation is a typical partial differential equation(PDE) which can generally be solved by analytical method or numericalmethod. Analytical method can give an exact solution of PDE, but only
available for infinite or semi-infinite medium or other certain regular
geometries. On the contrary, numerical method is only able to obtainapproximate solution of PDE but have no limitation on the shape of
medium. Finite element method (FEM) is a major numerical approachfor PDE. It uses Galerkin method to attain an approximate solution on
an arbitrary mesh. The type of mesh in FEM is optional, but fine meshes
consisting of linear element are often chose. However, although thelinear element could improve the time consumption for calculation,
its accuracy is much lower than that of the high order elements atthe same size of mesh. In this paper, we investigate the differences
between the linear and quadratic triangular element in the forward
problem of diffuse optical tomography. The results show that thequadratic element is a better compromise between high accuracy andlow time consumption compared to the linear element. This means highorder element is a better choice for diffuse optical tomography.

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We are proposing a new method for enhancement of optical clearing
agent delivery into the skin using fractional laser microablation of theskin surface. Fractional laser microablation was used to overcome theprotective skin barrier. The Palomar Lux2940 erbium laser (Palomar
Medical Products Ltd., USA) was used as a light source. Its parameters
were the following: the wavelength 2940 nm, the pulse energy from 0.8
to 1 J. The pulses possessed a spike structure (from one to three spikes
per pulse depending on the energy) with the spike duration of 5 ms. The
microchannels were produced by means of a probe that allowed microablation of skin areas as multiple dots. In vitro and in vivo studies haveshown that laser fractional ablation enhance the penetration depth anddiffusion rate of PEG-300 and mineral oil in the skin tissue. The diffusion
measurements were performed using the Spectral Radar OCT System
OCP930SR 022 (Thorlabs Inc., USA) at a wavelength of 930 nm. The
values of permeability and diffusion coefficients of the investigatedchemicals in the tissue are presented.

8553-95, Poster Session

Three dimensional manipulations of cells
using holographic optical tweezers
Tao Tao, Jing Li, Yang Lin, Univ. of Science and Technology ofChina (China)
Optical tweezers technology can be used to trap particles ranging insize from tens of nanometers to several hundreds micrometers withtrapping forces from fN to nN. It is charaterized with non-touch, noharm to the sample,operation in the liquid enviroment and so on.
Therefore, it has been applied in the area of life science to manipulate
cells, stretch DNA, etc.
Recently, more attention has been paid to the application of opticaltweezers on single cell analysis. In order to avoid regarding individual
behavior of single cell as colony behavior, statistic investigation ona number of related cells is needed while single cell is studied. Thisrequirement can be satisfied by using holographic optical tweezers
to manipulate multiple cells simultaneously. In addition, the study
has proved that hepatocytes cultured as a monolayer can quickly
lose special functions, whilst those same cells in a quasi 3D collagenmatrix retain their normal functions for weeks in culture. So, culture
and differentiation of cells are infleuenced by distribution position,
proximity and number of the nearby biological particles. Holographic
optical tweezers can produce multiple traps which can be controlledindividually, and can create new and complex 3D micro-structures. It
provides experimental tools to study functions and behaviors of single
cell in multi-body structures.
A holographic optical tweezers system is presented with yeast cellas trapped objects, experiments on 3D trapping and manipulation ofmultiple cells and building 3D strutures are performed in it.

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8553-96, Poster Session

Photoacoustic measurement for glucose
solution concentration based on tunable
pulsed laser induced ultrasound
Zhong Ren, Guodong Liu, Zhen Huang, Dengji Zhao, Jiangxi
Science and Technology Normal University (China)
Noninvasive blood glucose concentration(BGC) measurement has
become a research hotspot. Up to now, some noninvasive BGC
measurement methods have been researched. e.g. near-infrared
spectroscopy, Raman spectroscopy, fluorescence detection, OCT.
Although some progresses have been achieved, many problems arestill in researching, such as, strong light-scattering disturb for tissues,
individual difference and complexity of human system. However,photoacoustic(PA) spectroscopy have better advantages than others
because of the detected ultrasonic waves instead of photon, which
overcomes the drawback of scattering light and has higher contrast
and resolution. In this paper, a custom-built tunable OPO pulsed laser
induced ultrasonic system was established. In this system, the focusedultrasound transducer was used to detect PA signals of glucose. In theexperiment, forward PA detection mode was employed. To determine
the characteristic wavelength of glucose, the tunable wavelengthof OPO laser was adjusted from 1300nm to 2400nm with intervalof 10nm. And the distilled water and five different concentrations of
glucose aqueous solutions with 50, 100, 150, 200 and 250mg/dl were
measured. Experimental result shows that the PA profiles of glucose
solutions are highly consistent to other literatures’ reports. By mean ofthe difference of PA peak-to-peak values between glucose solutions
and distilled water, several wavelengths, i.e. 1410nm, 1510nm, 1890nm,
2020nm and 2130nm are relatively determined as optimal wavelengths.
And the prediction error of glucose concentration by means of fitting
algorithm is less than 0.28mmol/L, which is too much better than thatof other methods. Therefore, the PA method has large potential value in
BGC measurement.

8553-97, Poster Session

Preliminary study on the estimation of
epidermal melanin content using diffuse
reflectance spectra
Ying Wang M.D., Chinese PLA General Hospital (China);
Xiaohua Liao, Fujian Metrology Institute (China); Ying Gu,
Chinese PLA General Hospital (China); Rong Chen, Fujian
Normal Univ. (China)
Objectives: The object of this study is to characterize the epidermalmelanin content of Chinese skin by diffuse reflectance spectra, andevaluate the melanin content change after photodynamic therapy for
port wine stains.
Methods: Firstly, diffuse reflectance spectra of normal transplantskin flap skin were measured in vivo in eighteen mildly burned
patients before surgery, and Fontana-Masson stain was made in thepathological sections. Epidermal melanin contents were analyzed byimage analysis software. Then, least squares fitting was performed tothe experiment points from 620-700nm, and the slope of this straightline which corrected with the melanin content was calculated. A
semiquantitative relationship between epidermal melanin contents andthe slope values was established. Further, diffuse reflectance spectra of
PWS patients with various degree of pigmentation were measured, andepidermal melanin contents were estimated approximately. In addition,
Monte Carlo algorithm was utilized to investigate the light distribution
character of 532 nm laser deposited in PWS skins with various degreeof pigmentation.
Results: The epidermal melanin contents estimated with FontanaMasson stain in these eighteen patients was 5~20%. The slope
values were -0.00158 to 0.000592, and reduced with melanin content
increasing. The slope value of PWS patient with pigmentation was

smaller than PWS without pigmentation. The 532 nm laser depositedin PWS skin with high degree of pigmentation is much lower than PWS
without pigmentation.
Conclusions: Diffuse reflectance spectra have the potential to be
applied in establishing the epidermal melanin content and the degree of
pigmentation.

8553-98, Poster Session

Expansion of scattered phase matrix basedon Zernike polynomials
Haishui Ye, Zhishan Gao, Qianwen Wang, Kexin Bao, Xiaowei
Yang, Nanjing Univ. of Science and Technology (China)
Multiple scattering and absorption in biological tissue occurs thatscattered light’s polarization changes as incident angle and tissue’s
physical performance when beam bounds to spherical particles in theturbid media. Combined with the classical Mie scattering, radiativetransfer equation (RTE) is also introduced to describe dynamic energy
conservation. It has been demonstrated that RTE can in fact bederived from the electromagnetic theory of multiple wave scatteringin discrete random media under certain simplifying assumption.
Obviously, the key is to solute RTE. There exists three variables in the
RTE, including polar angle, azimuthal angle and normalized penetrate
depth. In order to solute this equation with double integral on polar
angle and azimuthal angle, the first step is to introduce proper method
to isolate the azimuthally dependency from polar angle, commonly
including Fourier series and Legendre polynomials expansion. In thispaper, we put forward a novel phase matrix expansion with Zernike
polynomials, which represents the probability of scattering events.
Specifically, orthogonal Zernike polynomial in square integral region
has been derived from Gram-Schmidt orthogonalization. The results
show that it can provide a new improved strategy for the solution ofradiative transfer equations in Discrete-Ordinate Method (DOM), andthe final solution for scattered lights’ polarization greatly coincide withthe results from Spherical Harmonic Method (SHM). Besides, we also
extend this orthogonal decomposition of scattered phase matrix tomore orthogonal basis.

8553-99, Poster Session

Optical-resolution photoacoustic
microscopy for imaging blood vessels in vivo
Yi Yuan, South China Normal Univ. (China)
An optical-resolution photoacoustic microscopy system wasdesigned and fabricated by integration of a two-dimensional scanninggalvanometer, an objective lens, an unfocused ultrasound transducer
and a sample stage for imaging blood vessels in vivo. The lateral
resolution of the system was measured to be ~5 µm. In vivo bloodvessels of mouse ear were clearly shown and the injured blood vessels
were also monitored. The experimental results demonstrate thatgalvanometer-based photoacoustic microscopy holds clinical potential
in detecting lesion of blood vessels.

8553-100, Poster Session

Optical characters of prostate using
nonlinear optical microscopy
Shulian Wu, Hui Li, Xiaoman Zhang, Fujian Normal Univ. (China)
The incidence rate of the prostatic hyperplasia is increasing in neardecade, early detection is important for preventing the prostatic cancer(PCa). In this study, the imagines of prostate and cavernous nerves
were carried out using intrinsic fluorescence and scattering propertiesof the tissues without any exogenous dye or contrast agent based on

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Conference 8553:
Optics in Health Care and Biomedical Optics V
nonlinear optical microscope. The texture feature and optical propertyof the interfibrillar substance in prostate tissue were extracted andanalyzed for charactering the prostate structure. It will be the featureparameter to differentiate the normal, the inflammation or cancer of
prostate tissue in clinical with the application of miniature endoscope
nonlinear optical microscope in vivo.

8553-101, Poster Session

Crystalline lens surgery: cutting quality
and safety evaluation of femtosecond laser
pulsesJiaying Zhang M.D., Chinese PLA General Hospital (China); Rui
Wang, Institute of Physics (China); Bin Chen, Hongyou Zhao,
Ying Gu, Chinese PLA General Hospital (China)
A femtosecond laser-induced crystalline-lens micro-cut procedure foralleviating presbyopia has received attention recently. We determinedthe efficiency and safety of this promising strategy using opticalmeasurements of the distribution of pulse energy as light passes
through the eyeball. Laser pulses of 35 fs in duration were used toperform in vitro cutting of porcine lens. The transmittance through therefractive media was measured to be 69%~84% according to different
input energies. Our data illustrate the theoretical feasibility and safetyof the procedure. The results recommend the use of nanojoule laser
pulses combined with high numerical aperture optics.

8553-102, Poster Session

Effect of apertures in ultrasound-modulated
optical tomography with photomultiplier
tube
Lili Zhu, Shubing Ran, Zhiyuan Lin, Hui Li, Fujian Normal Univ.
(China)Improving signal to noise ratio in ultrasound-modulated optical
tomography (UOT) is a research topic. Laying apertures in front of aphotomultiplier tube (PMT) can reduce the ambient noise collectedby the PMT, and efficiently improve the signal to noise ratio of UOT. In
addition, the effective area of detection and the off-axis position of the
PMT would be varied by changing the aperture size and position in frontof the PMT. Experimental results indicated that the modulation depthof ultrasound-modulated signal is dependent on the area of detection.
The greater the detector area, the smaller the modulation depth. The
modulation depth also depended on the off-axis position of the PMTfrom the optic axis. In particular, the modulation depth did not reach thebiggest value when the PMT just placed on the optics axis. Choosing
appropriate size, position of aperture, can improve modulation depth
and image contrast.

further, these technology mentioned below could not trap particles by
only one optical fiber.
Now there many structures of single optical tweezers. In the experiment
the researchers found that some of these optical tweezers could
trap multi-particles simultaneously. Actually the conventional opticaltweezers also has this ability of trapping multi-particles. But it isdifficult to observe this phenomenon because the viewing field of theconventional optical tweezers is perpendicular to the trapping direction.
So there is no further research on it. The trapping direction of the fiber
optical tweezers exists in the focal plane of the imaging. And it makes
the research of the multi-particles trapping meaningful
We propose a novel tapered-tip single fiber optical tweezers, which canrealize micro particles multi-trapping. The theory analysis about multitrapping was finished with the finite difference time domain (FDTD)
method. The theory and experiment results showed that the particle
refractive index affects the multi-trapping obviously.

8553-104, Poster Session

Scattering properties of normal andcancerous tissues from human stomach
based on phase-contrast microscope
Hui Zhang, Zhifang Li, Hui Li, Fujian Normal Univ. (China)
In our experiment, all fresh tissue specimens from human stomach
were frozen and cut on a microtome (HM550,Microm) to a thicknessof 5-um. These unstained tissue slices are microscopic phase objects,
its structural information mostly reflect in the refractive index, notamplitude contrast. So we use a phase-contrast microscope (TS100,
Nikon) to measure variations in refractive index and observe structural
information of each slice. All phase-contrast images were acquired withtaken at magnifications of 100?,200?,400? with a CCD camera(TCA5.0C, Tucsen).
Next, images were processed by Matlab software. Mie scattering
theory suits for spherical particles as a conventional model. In order tostudy scattering properties of normal and cancerous tissues, therefore,
we analyze phase-contrast images using multiscale mathematicalmorphology. Creating disk structure elements, and opening operation
with a series of various radius on image, we can obtain particle size
distribution of tissues.
Assume scattering of light in biological tissue can be seen as separate
scattering events by different particles, total scattering properties canbe equivalent to as scattering sum of particles with different diameters.
According to classical algorithm of Mie scattering providing an exact
solution, scattering properties parameters of tissue including scattering
coefficient, reduced scattering coefficient, mean cosine of scattering
angle, phase function can be calculated.
Compared with normal tissue, we found that scattering coefficient andreduced scattering coefficient of cancerous tissue is significantly higher,mean cosine of scattering angle is approximately equal, scattering
phase function is different especially in the backscattering area.

8553-103, Poster Session

8553-105, Poster Session

The tapered-tip single fiber optical tweezers
and its multi-trapping

Retrieval of atmospheric visibility frommulti-axis differential optical absorption
spectroscopy

Xiaolei Guo, Zhihai Liu, Yuanheng Zhao, Libo Yuan, Harbin
Engineering Univ. (China)
Since 1986 Ashkin presented the concept about optical trapping, theoptical tweezers have been rapidly developed in the following years.
Especially, in the area of bioscience, optical tweezers have become
one of the most effective tools in doing research on single cells andbiomacromolecule because of its ability of controlling nano-scaleparticles without contacting and damaging them.
The early fiber optical tweezers using two or more optical fibers guiding
light beams to build a large gradient for trapping[].Then as the need for

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Haijin Zhou, Univ. of Science and Technology of China (China);
Wenqing Liu, Fuqi Si, Anhui Institute of Optics and Fine
Mechanics (China)
The multi-axis differential optical absorption spectroscopy (MAX-DOAS)
technique is being widely used in the monitoring of trace gases column
density. In this paper, a retrieval method of visibility from O4 slant
column density measured with MAX-DOAS is present. O4 slant column
density is sensitive to the change of aerosol properties, and aerosol
properties determines the atmospheric visibility. The relationship

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of atmospheric visibility and O4 slant column density is analyzed,
and a retrieval algorithm to convert the O4 differential slant column
density into the surface mixing ration with the information of visibility
is described. MAX-DOAS observation is carried out at HeFei, andatmospheric visibility is retrieved successfully. The visibility measured
with MAX-DOAS shows good agreement with the result obtained withvisibility meter, proving the feasibility of the retrieval method. This
research presents a simple and effective monitoring method of visibility
with MAX-DOAS, expands the application of MAX-DOAS technique.

staging of prostate cancer, such as ultrasound, CT, MRI, etc. But
they lacked adequate sensitivity and specificity for finding cancer intransition or central zone of prostate. To overcome these problems,
we propose a photoacoustic imaging modality based on cylinder
diffuse radiation through urethra for prostate cancer detection. The
related parameters, such as resolution, imaging depth and so on, were
employed with this system. Finally, in vitro canine prostate as a sample
was imaged. The results demonstrate the feasibility for detecting
prostate cancer.

8553-106, Poster Session

8553-109, Poster Session

Monte Carlo Simulation of Photon Coherent
Behavior in Half Infinite Turbid Medium by
Scaling Method

Realization of the ergonomics design andautomatic control of the fundus cameras

Lin Lin, Guangdong Medical College (China); Mei Zhang,
Huazhu Liu, Dongguan University of Technology (China)
A method of coherent measuring optical parameters of scattering
medium is presented based on Monte Carlo simulation. The condensed
scaling method is introduced to accelerating process of calculation. A
tri-layer structure BP-artificial neural network is developed for reverse
calculation of scattering and absorption coefficients of medium. Fatemulsion and stain mixture of IntralipidTM and India ink are taken as
scattering and absorbing sample for coherent measurement by fiberMichelson interferometer. Results of experiments have shown linear
relation between scattering or absorption coefficients and concentrationof IntralipidTM or India ink. The method is helpful to nondestructive
testing components of turbid material.

Chiliang Zeng, Zexin Xiao, Shichao Deng, Xinye Yu, Guilin Univ.
of Electronic Technology (China)
The design principle of ergonomics design in fundus cameras should
be extending the agreeableness by automatic control. Firstly, a 3D
positional numerical control system is designed for positioning the eyepupils when patient doing fundus examinations. This system consistsof a electronically controlled chin bracket for moving up and down, alateral movement of binocular with the detector and automatic focusingof the edge of the eye pupils. Secondly, a auto-focusing device for theobject plane of patient’s funds is designed, which collects the patient’s
fundus images automatically whether their eyes is ametropic or not.
Finally, a moving visual target is developed for expanding the field of thefundus images.

8553-110, Poster Session
8553-107, Poster Session

In vivo detection of hemoglobin oxygen
saturation and carboxyhemoglobin
saturation variations with photoacoustic
microscopy
Zhongjiang Chen, Yang Sihua, Da Xing, South China Normal
Univ. (China)
Almost all pulse oximeters in common use measure tissue lighttransmission at two wavelengths (two colors) to estimate arterial
hemoglobin saturation. If any other light absorbers are present
in the blood, the pulse oximeter’s calibration may be invalid. The
carboxyhemoglobin(HbCO) is the most life-threatening in blood in
CO poisoning. In this study, a method for noninvasive detecting
hemoglobin oxygen saturation (SO2) and carboxyhemoglobin saturation(SCO) in subcutaneous microvasculature with multi-wavelength
photoacoustic microscopy is presented. Blood samples mixed withdifferent concentrations of carboxyhemoglobin were used to test thefeasibility and accuracy of the photoacoustic microscope comparing
with the blood-gas analyzer. Moreover, fixed-point detection of SO2
and SCO in mouse ear was obtained, and the changes from normoxia
to carbon monoxide hypoxia were dynamically monitored in vivo.
Experimental results demonstrate that multi-wavelength photoacoustic
microscopy can detect SO2 and SCO, which has future potential
clinical applications.

Laser speckle contrast imaging for early
acute myocardial ischemia of rat
Biying Yu, Hui Li, Fujian Normal Univ. (China); Haiyu Chen,
Fujian Medical Univ. (China); Shusen Xie, Fujian Normal Univ.
(China)Nowadays, cardiovascular diseases that threat to human life andhealth have become main diseases with an obvious rising incidence.
Myocardial ischemia is the most of the focus on cardiovasculardiseases. The change of microcirculation blood flow and the process of
myocardial ischemia are closely related. Laser speckle contrast imaging
provides full-field and real-time investigation of microcirculation bloodflow in vivo with several outstanding characteristics that including
non-contact, noninvasive and high speed imaging. An acute myocardialischemia model of rat is established by the ligation of the left anterior
descending branch in this study. Images that reflect blood flow of thefront wall of left ventricle in different ligation time are attained by laser
speckle contrast imaging. And some data for evaluating myocardialischemia degree are obtained used laser speckle contrast imaging.

8553-111, Poster Session

Study the effect of temperature on opticalproperties of biological tissue-simulating
phantom based on OCT

8553-108, Poster Session

Youwu He, Hui Li, Fujian Normal Univ. (China)

Photoacoustic imaging of prostate cancer
using cylinder diffuse radiation

In the basic research area, people would like to study the effects oftemperature on optical properties measurement of tissue-simulating
sample and vitro tissue. Many methods has been used such as
near-infrared spectrum technology and CCD diffusing reflection
measurements etc. In our research, we use optical coherence
tomography (OCT) technology to study the effect of temperature on the
optical properties of biological tissue by using intralipid as an example.
OCT imaging is based on the differences of backscatter light, in the

Wenming Xie, Hui Li, Li Li, Fujian Normal Univ. (China)
Prostate cancer is one of diseases with high mortality in man. Many
clinical imaging modalities are used for the detection, grading and

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Conference 8553:
Optics in Health Care and Biomedical Optics V
model, OCT is assumed to detect light that only scattered once, andthus the decay of the OCT signal with depth function fellows the bearLambert law. According to the beer-Lambert law, we can easily obtain
information on sample scattering properties. Put the sample in theelectric heating constant temperature pot(working accuracy:±0.5°C),
and we measure the optical prosperities in the temperature range of
25-40°C. The temperature span is 5°C. The results show that obvious
decrease can be observed with increasing temperature in the reduced
scattering coefficient. The results were in contrast with those reported
results on the study of ex vivo tissue, and they were coherent. The
results demonstrate that OCT is an effective and novel method to study
the effect of temperature on optical properties of biological tissue.

8553-112, Poster Session

Miniature interferometer for refractive index
measurement in microfluidic chip
Minghui Chen, Univ. of Shanghai for Science and Technology(China); Martial H. Geiser, Frederic Truffer, Univ. of Applied
Sciences Western Switzerland (Switzerland); Chengli Song,
Univ. of Shanghai for Science and Technology (China)
The design and development of the miniaturized interferometerfor measurement of the refractive index or concentration of submicroliter volume aqueous solution in microfludic chip is presented.
It is manifested by a successful measurement of the refractive index
of sugar-water solution, by utilizing a laser diode for light source
and the small robust instrumentation for practical implementation.
Theoretically, the measurement principle and the feasibility of thesystem are analyzed. Experimental device is constructed with a diodelaser, lens, two optical plates and CMOS. Through measuring thepositional changes of the interference fringes, the refractive index
change are retrieved. A refractive index change of 10-4 is inferred fromthe measured image data. The entire system is approximately the sizeof half and a deck of cards and can operate on battery power for longtime.

8553-113, Poster Session

Study for noninvasive determination of
optical properties of bio-tissue using
spatially resolved diffuse reflectance
Dongqing Peng, Fujian Normal Univ. (China) and Jimei Univ.
(China); Hui Li, Fujian Normal Univ. (China)
The optical characteristic of absorption and scattering of irradiatedtissue determine light spatial distribution and the subsequent biologicaleffects, which can decide the dosimetry for laser medical applications.
Based on the measurement of diffuse reflectance obtained by Monte
Carlo simulation, the optical properties of bio-tissue were determinedthrough the nonlinear least-square algorithm with spatially resolved
diffuse reflectance theory in the first. and the data scope, data
space,even start value for the nonlinear regression were discussed
in detail.Then, a laser scattering imaging system based on digital
camera was designed by ourselves for measurement radial distributionof diffuse reflectance light at 632.8nm from several bio-tissues. The
absorption and reduced scattering coefficients are derived by nonlinear
fitting of diffusion equation with the relative distribution data of diffuse
reflection light intensity. The results were compared with the reported
results and show the feasibility of theoretical model and experiment
method. Study indicate that the appropriate regression of noninvasive
measurement of radial dependence of the diffuse reflectance and amore accurate light diffuse reflectance theoretical model are required
to provide the possibility to obtain the optical parameters of biologicaltissues.

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8553-114, Poster Session

Development of an in situ magnetic
beads based RT-PCR method forelectrochemiluminescent detection ofrotavirus
Fangfang Zhan, Xiaoming Zhou, South China Normal Univ.
(China)Rotaviruses are double-stranded RNA viruses belonging to the familyof enteric pathogens. It is a major cause of diarrhoeal disease in infants
and young children worldwide. Consequently, rapid and accurate
detection of rotaviruses is of great importance in controlling andpreventing food- and waterborne diseases and outbreaks. Reverse
transcription-polymerase chain reaction (RT-PCR) is a reliable methodthat possesses high specificity and sensitivity. It has been widelyused to detection of viruses. Electrochemiluminescence (ECL) can
be considered as an important and powerful tool in analytical andclinical application with high sensitivity, excellent specificity, and low
cost. Here we have developed a method for the detection of rotavirus
by combining in situ magnetic beads (MBs) based RT-PCR with ECL.
RT of rotavirus RNA was carried out in a traditional way and theresulting cDNA was directly amplified on MBs. Forward primers werecovalently bounded to MBs and reverse primers were labeled withtris-(2, 2’-bipyridyl) ruthenium (TBR). During the PCR cycling, the TBR
labeled products were directly loaded and enriched on the surface ofMBs. Then the MBs-TBR complexes could be analyzed by a magnetic
ECL platform without any post-modification or post-incubation, which
avoid some laborious manual operations and achieve rapid yet sensitive
detection. In this study, rotavirus from fecal specimens was successfully
detected within 2 h, and the limit of detection was estimated to be
104copies/µl. This novel in situ MBs based RT-PCR with ECL detection
method can be used for pathogen detection in food safety field andclinical diagnosis.

8553-115, Poster Session

ERK-dependent activation of Sp1 is required
for low-power laser irradiation-induced
vascular endothelial cell proliferation
Jie Feng, Da Xing, South China Normal Univ. (China)
Angiogenesis participates in developmental and pathologicalneovascularization, during which proliferation of vascular endothelial
cells is a crucial procedure. The role of low-power laser irradiation(LPLI) in promoting cell proliferation has been widely spread in clinicalfor decades of years. Therefore, the effect of LPLI on proliferation may
offer clinically therapeutic options to facilitate angiogenesis. However,the underlying mechanisms are not fully elucidated. Here, we reportthat LPLI activates ERK/Sp1 (Extracellular signal-Regulated Kinase /Specificity protein 1) pathway to upregulate VEGF expression andpromote vascular endothelial cell proliferation. Using a Sp1 luciferase
reporter and chromatin immunoprecipitation analysis, we demonstrate
for the first time that LPLI enhances DNA-binding activity andtransactivation activity of Sp1 on VEGF promoter. The results from realtime single-cell analysis suggest that ERK translocates from cytoplasm
to nucleus following LPLI. More importantly, activated ERK by LPLI
phosphorylates Sp1. FRET method and co-immunoprecipitation revealthat the interaction between ERK and Sp1 is gradually increasing.
In addition, selective inhibition of Sp1 by mithramycin A or shRNA
suppresses the effect of LPLI on the promotion of vascular endothelial
cell cycle progression and proliferation, which is also significantly
abolished by inhibition of ERK with PD98059, a specific inhibitor of
MEK. These findings provide a novel link between LPLI and endothelial
proliferation, an essenial procedure of angiogenesis, supplying potential
therapy strategies for vascular pathologies through ERK/Sp1 signalling
pathway with LPLI.

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8553-117, Poster Session

8553-119, Poster Session

Iterative reconstruction for bioluminescence
tomography with total variation
regularization

Low-power laser irradiation protects
mitochondrial function and inhibits MPP+induced neuron loss through the activationof PGC-1[alpha]Wenma Jin, Peking Univ. (China); Yonghong He, Beijing
Aerospace Control Ctr. (China)
Bioluminescence tomography(BLT) is an instrumental molecularimaging modality designed for the 3D location and quantification of
bioluminescent sources distribution in vivo. In our context, the diffusion
approximation (DA) to radiative transfer equation(RTE) is utilized tomodel the forward process of light propagation.
Mathematically, the solution uniqueness does not hold for DA-based
BLT which is an inverse source problem of partial differential equations
and hence is highly ill-posed. In the current work, we concentrate on a
general regularization framework for BLT with Bregman distance as data
fidelity and total variation(TV) as regularization.
Two specializations of the Bregman distance, the least squares(LS)distance and Kullback-Leibler (KL) divergence, which correspond to theGaussian and Poisson environments respectively, are demonstrated
and the resulting regularization problems are denoted as LS+TV
and KL+TV. Based on the constrained Landweber (CL) scheme andexpectation maximization(EM) algorithm for BLT, iterative algorithms for
the LS+TV and KL+TV problems in the context of BLT are developed,
which are denoted as CL-TV and EM-TV respectively. They are bothessentially gradient-based algorithms alternatingly performing thestandard CL or EM iteration step and the TV correction step which
requires the solution of a weighted ROF model. Chambolle’s dualitybased approach is adapted and extended to solving the weighted ROF
subproblem. Numerical experiments for a 3D heterogeneous mouse
phantom are carried out and preliminary results are reported to verify
and evaluate the proposed algorithms. It is found that for piecewiseconstant sources both CL-TV and EM-TV outperform the conventional
CL and EM algorithms for BLT.

Juan Wang, Shengnan Wu, Da Xing, South China Normal Univ.
(China)Parkinson’s disease (PD) is a pervasive neurodegenerative disease
which results from the loss of the dopaminergic neurons in thesubstantia nigra pars compacta. 1-methyl-4-phenylpyridinium (MPP+)
induced mitochondrial dysfunction and oxidative stress have been
implicated in PD model. Previous studies show that low-power laser
irradiation (LPLI) can reverse MPP+-induced decrease of mitochondrial
membrane potential and neurons loss. However, the underlying
mechanisms are unknown. In the present study, we first reported thatLPLI promoted peroxisome proliferator-activated receptor g coactivator
1 (PGC-1a) expression and activation, which decreased the number ofneurons undergoing apoptosis, and significantly reduced the excessive
reactive oxygen species in MPP+-exposed neurons. Inhibition of
PGC-1a expression by siRNA significantly abolished the effect of LPLI.
We also discovered that MPP+-induced neurons toxicity declined thephosphorylation of cAMP-responsive element-binding protein (CREB),a main regulator of PGC-1a expression, which was recovered by LPLI
in an extracellular signal-regulated kinase (ERK) dependent manner.
Therefore, LPLI protects neurons from MPP+-induced apoptosis
through ERK/CREB/PGC-1a pathway. These data provide a newclue that PGC-1a may be a potential target for the PD therapeutic
manipulation with LPLI treatment.

8553-120, Poster Session

Amplification-free detection of miRNA via an
ECL chips system8553-118, Poster Session

Weipeng Liu, Xiaoming Zhou, South China Normal Univ. (China)

Imaging the morphological change oftissue structure during the early phaseof esophageal tumor progression using
multiphoton microscopy

MicroRNAs play pivotal roles in many fundamental aspects oflife, such as plant and animal development, tissue differentiation,
metabolic modulation and cell proliferation control. As miRNA with thecharacteristics of small size, easy degradation and low abundance, a
simple, rapid and specificity method to measure the concentration of
miRNA is required. Herein, we present an Electrochemiluminescent
Chips system for rapid microRNA detection based on the basestacking hybridization and magnetic beads(MB) enrichment
technology. In this design, integrating the microfluidic system with
Electrochemiluminescent detection makes it easy to assemble themultiple assay steps (e.g., sample preparation, incubation, washing anddetection) and let the device convenient to carry. This method is very
fast, we can detect miRNA-21 in 15 min with a 10 uL sample volume.
Moreover, in this experiment the detection limit was 0.1 nM or 1 ug total
small RNA(20-200 nt) from human tissues, and the linear range from
0.1 nM to 50 nM. It also exhibited excellent selectivity over a series ofinterference miRNA, which display a high level of expression in cancercell. These results suggest that this method might have potential forcancer diagnosis at the point of care.

Jian Xu, Fujian Normal Univ. (China); Deyong Kang, Meifang Xu,
Fujian Medical Univ. (China); Jianxin Chen, Fujian Normal Univ.
(China)Esophageal cancer is one of the most common cancer and leading
cause of cancer death worldwide. Like most other cancers, early
detection is important to improve the quality of life in patient and reduce
mortality. Multiphoton microscopy (MPM) is becoming a novel optical
tool of choice for imaging tissue architecture and cellular morphology by
two-photon excited fluorescence. In this study, we used MPM to image
the morphological change of tissue structure during the early phase of
esophageal tumor progression, including human normal esophagus,
carcinoma in situ, and early invasive carcinoma. We extracted the
diagnostic features to distinguish between normal and cancerous
esophagus tissue, such as the appearance of cancerous cells, theabsence of the basement membrane. We also quantitatively describedthe differences of morphology between normal and cancerous cells.
These results correlated well with the paired histological findings. With
the advancement of clinically miniaturized MPM and the multi-photonprobe, combining MPM with standard endoscopy will therefore allow us
to make a real-time in vivo diagnosis of early esophagus cancer at thecellular level.

8553-121, Poster Session

Label-free and sensitive fluorescence
detection of nucleic acid, based on
combination of a graphene oxid /SYBR
green I dye platform and polymerase
assisted signal amplification
Xiao Zhu, Da Xing, Xiaoming zhou, South China Normal Univ.

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Conference 8553:
Optics in Health Care and Biomedical Optics V(China)A new label-free isothermal fluorescence amplification detection for
nucleic acid has been developed. In this paper, we first developed anovel sensitive and specific detection platform with an unmodified
hairpin probe (HP) combination of the graphene oxid (GO) / intercalatingdye, which was relied on the selective principle of adsorption and thehigh quenching efficiency of GO. Then for the application of this new
strategy, we used Mirco RNA-21 (Mir-21) as the target to evaluate thisworking principle of our design. When the target was hybridizing with
the HP and inducing its conformation of change, an efficient isothermal
circular strand-displacement polymerization reaction was activating toassist the first signal amplification. In this format, the formed complex
conformation of DNA would interact with its high affinity dye, thendetached from the surface of GO after incubating with the platform of
GO/intercalating dye. This reaction would accompany with obvious
fluorescence recovery, and accomplish farther signal enhancement
by a mass of intercalating dye inserting into the minor groove of thelong duplex replication product. By taking advantage of the multiple
amplification of signal, this method exerted substantial enhancement insensitivity and could be used for rapid and selective detection of Mir-21
with attomole range. It is expected that this cost-effective GO based
sensor might hold considerable potential to apply in bioanalysis studies.

8553-122, Poster Session

Histopathologic change of rabbit retinal
injury induced by continuous 1.319um laser
Jiarui Wang, Zaifu Yang, Academy of Military Medical Sciences(China)Objective To explore the characteristics and histological change of
rabbit retinal after irradiation of continuous 1.319µm laser in different
exposure time. Methods A Nd: YAG laser was used to deliver 1.319µm
laser to the retinas of 15 pigmented rabbits. The exposure time was
0.1s, 1s and 10s respectively. The irradiated site and its instantly
change was obtained by ophthalmoscope. The histological evaluation
and recordance were performed at 1h, 24h, 48d, 3d and 7d after
irradiation. The eyeballs was fixed in Davidson’s fixative solution.
Results White coagulation macula with unsharp borderline anddispersion of pigments was discovered immediately after irradiation.
There occurred new injury macular after 24h which showed retina
buninoidly eminence, retinal structure derangement, RPE swelling,
photoreceptor collapse and ganglion cells degeneration or dropsy.
When the exposure time was 10s the corneal and crystalline lens
were damaged simultaneously. Conclusion The mechanism of theretinal injury induced by continuous 1.319µm laser is photothermal
damage mainly with heat production by absorption the energy of laser.
It suggested that the degree of the damage depends on both theexposure time and irradiation dose which become more serious withlarger dose at given exposure time.

8553-123, Poster Session

Photoacoustic spectroscopic differences
between normal and malignant thyroid
tissues
Li Li, Wengming Xie, Fujian Normal Univ. (China); Shuqiang
Chen, Fujian Medical Univ. (China); Hui Li, Fujian Normal Univ.
(China)The thyroid is one of the main endocrine glands of human body,which plays a crucial role in the body’s metabolism. Thyroid cancer
mortality ranks only second to ovarian cancer in endocrine cancer.
Routine diagnostic methods of thyroid diseases in present clinic exist
misdiagnosis and missed diagnosis to varying degrees. Those leadto miss the best period of cancer treatment--early. Photoacoustic
spectroscopy technology is a new tool, which provides an effective

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and noninvasive way for biomedical materials research, being highly
sensitive and without sample pretreatment. In this paper, we use
photoacoustic spectroscopy technology to detect the absorption
spectrum between normal and malignant thyroid tissues. The resultshows that the photoacoustic spectroscopy technology could
differentiate malignant thyroid tissue from normal thyroid tissue very
well. This technique combined with routine diagnostic methods has thepotential to increase the diagnostic accuracy in clinical thyroid cancer
diagnosis.

8553-124, Poster Session

Ex-vivo endoscopic laryngeal cancer
imaging using two forward-looking fiber
optic scanning endoscope probes
Ramona C. Cernat, Univ. of Kent (United Kingdom); Taran Tatla,
Jingyin Pang, Paul J. Tadrous, Northwick Park Hospital (United
Kingdom); Grigory V. Gelikonov, Valentin M. Gelikonov, Instituteof Applied Physics (Russian Federation); Yuying Y. Zhang,
Johns Hopkins Univ. (United States); Adrian Bradu, Univ. ofKent (United Kingdom); Xingde Li, Johns Hopkins Univ. (UnitedStates); Adrian Podoleanu, Univ. of Kent (United Kingdom)
Larynx cancer is one of the most common primary head andneck cancers. For early-stage laryngeal cancer, both surgery andradiotherapy are effective treatment modalities, offering a high rateof local control and cure. Optical coherence tomography (OCT)
is an established non-invasive optical biopsy method, capable ofimaging ranges of 2-3 mm into tissue. By using the principles oflow coherence light interferometry, OCT can be used to distinguishnormal from unhealthy laryngeal mucosa in patients. Two forwardlooking endoscope OCT probes with different sizes in a sweeping
frequency OCT configuration (SS-OCT) were compared in terms of theirperformances (transversal resolution, sensitivity, and signal to noise
ratio) for ex-vivo laryngeal cancer imaging.
The setup configuration of the first OCT probe unit was designed andconstructed at the Institute of Applied Physics RAS, Russia (diameterof 1.9 mm and the rigid part at the distal end is 1.5 cm long). The
second OCT endoscope probe was constructed at the Departmentof Biomedical Engineering at Johns Hopkins University, USA, using atubular piezoelectric actuator with quartered electrodes in combination
with a resonant fiber cantilever (diameter of 2.4 mm, and rigid part of
4.5 cm.)B-scan images of diseased laryngeal tissue using the two OCT
configurations were aquired and compared with OCT images obtainedin a 1310 nm SS-OCT classical non-endoscopic system. The work
presented here is an intermediate step in our research towards in-vivo
endoscopic laryngeal cancer imaging.

8553-125, Poster Session

Glucose and temperature sensitive
luminescence ZnCdS nanoparticles
Elena K. Volkova, Vyacheslav I. Kochubey, Julia G. Konyukhova,
N.G. Chernyshevsky Saratov State Univ. (Russian Federation)
We have investigated changes in the luminescence characteristics of
ZnCdS semiconductor nanoparticles depended on temperature andglucose concentration.
ZnCdS nanoparticles were synthesized from a mixture of aqueous
solutions of cadmium chloride (CdCl2) and zinc chloride (ZnCl2)
by addition of sodium sulphide solution at room temperature. The
nanoparticles were not stabilized. The ZnCdS nanoparticles solution
was added into aqueous glucose solution. Photoluminescence intensityof the particles strongly depended on glucose concentration byadding glucose oxydase. The degree of luminescence quenching is

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proportional the glucose concentration.
The luminescence spectra also changes with temperature. Its amplitudedecrease and luminescence maximum shifts into long-wave spectral
region.

refractive index and absorption coefficient based on THz transmission
spectroscopy system. Compared with reflection mode, it has an
obvious advantage, which is that transmission measurement consists
in data processing’s simplicity. What’s more, it is easy to realize highprecision parameters survey. And it is helpful to get the characters of
biological liquid sample in the far-infrared spectral region.

8553-126, Poster Session

Characterization of muscle drawing andinjury by polarization-sensitive opticalcoherence tomography
Dongsheng Chen, Nan Zeng, Celong Liu, Hui Ma, Graduate
School at Shenzhen,Tsinghua Univ (China)
In this paper, we study muscle elastic drawing and injury using ourlab’s polarization-sensitive optical coherence tomography (PS-OCT)
instrument and polarization sensitive Monte Carlo program. First, we
acquire two-dimensional PS-OCT images of elastic drawn and injured
muscle, injury processes including dehydration and hydrolysis, using
our instrument, and from the images, we extract such information of
the muscle as extinction coefficient, integral reflectivity, depolarization
coefficient and birefringence and so on, which is changing when muscle
is being elastically drawn or injured. In order to further understand anddemonstrate the relation between the information above, extracted
from experiments, and the degree of muscle elastic drawing or injury,
we do some corresponding simulations by our lab’s Monte Carlo
program, which is based on a sphere cylinder birefringence model andcan simulate complicated tissue containing anisotropic microstructuresand various polarization imaging and measurement systems. For
muscle elastic drawing, we find that integral reflectivity sometimes
increases and decreases as muscle’s elastic drawing continues, andthrough simulation we are unable to find the relationship between
extinction coefficients and muscle elastic drawing. As for muscle injury,
we simulate two processes: dehydration and hydrolysis. We find thatas dehydration deepens, the birefringence of muscle is increasing
but getting slowly and the integral reflectivity is decreasing, and ashydrolysis deepens, the birefringence is decreasing and the integral
reflectivity is almost decreasing linearly. Through the analysis above,
we demonstrate the validity of those parameters to characterize muscle
elasticity and fiber structure and explain its potential for assessment ofmuscle injury.

8553-127, Poster Session

Analysis on the characteristics of glucose
solution based on terahertz time domain
spectroscopy system
Zhao-feng Jiang, Wei Liu, Capital Normal Univ. (China)
With the rapid development of terahertz time domain
spectroscopy(THz-TDS) technology, the coherence detection ofterahertz pulse allows to obtain the samples’ phase and amplitude
information. Obviously, glucose is the most prevalent organic
compound in nature and is also a major source of metabolic energy.
So it is especially necessary to measure and analyze the propertiesof the glucose solution. The systematical measurement for glucose
concentration is the basis of diagnosing symptom, directing the
medicine’s usage and observing an effect. THz-rays have lower photon
energies, which they have no chance to generate ionizing radiation,and this make the higher precision analysis of glucose solution without
any damage possible. Therefore, it has an important scientific andmedical value in researching glucose solution and finding an accurate
measurement method of the concentration. In 2006, M.Nagel, etc, inGermany utilized reflection coherent terahertz waveguide to present
the results of alcohol solution and study the relationship between
concentration and refractive index , the extinction coefficient.
In this letter, our work is focused on what the quantitative relationshipbetween the concentration of aqueous glucose solution among

8553-47, Session 11

Dynamics of two-photon two-colortransitions in flurophores excited byfemtosecond laser pulses (Invited Paper)
Oleg S. Vasyutinskii, Peter S. Shternin, Andrey G. Smolin, Ioffe
Physico-Technical Institute (Russian Federation); Karl-Heinz
Gericke, Stefan Denicke, Sebastian Herbrich, Technische Univ.
Braunschweig (Germany)
We present the results of theoretical and experimental studies of thepolarized fluorescence in flurophores excited by two-photon two-color(2P2C) laser pulses. Quantum mechanical expressions describing thefluorescence polarization have been derived under the condition of
isotropic rotation diffusion for arbitrary polarization of each of the threephotons involved in the photoprocess.
The experiment has been carried out on p-terphenyl dissolved in
cyclohexane/ paraffin and with indol dissolved in methanol. The
fluorescence was produced within a 2C2P excitation scheme utilizing
simultaneous absorption of two femtosecond laser pulses in the
400-440 nm and in the 800-880 nm spectral range. Using different
combinations of the photon polarizations we extracted seven timedependent molecular parameters from experiment. The analysis of theobtained experimental data was based on the ab initio calculationsof the vertical excitation energies and transition matrix elements andallowed for determination of the whole structure of the two-photon
absorption tensor, fluorescence lifetime, and rotational correlation times.
This gives information on possible two-photon excitation channels andinteraction of flurophores with surrounding solute molecules.
1. P. S. Shternin, K.-H. Gericke, O. S. Vasyutinskii, Molecular Physics,
2010, 108, 813.
2. S. Denicke, K.-H. Gericke, A. G. Smolin, P. S. Shternin, O. S.
Vasyutinskii, J. Phys. Chem. A 2010, 114, 9681.

8553-49, Session 11

Dual color CW STED nanoscopy with a
Ti:Sapphire oscillator
Yujia Liu, Shanghai Jiao Tong Univ. (China); Eric Alonas, Philip
J. Santangelo, Georgia Institute of Technology (United States)
and Emory Univ. (United States); Dayong Jin, James A. Piper,
Macquarie Univ. (Australia); Qiushi Ren, Peng Xi, Peking Univ.
(China)Fluorescent microscopy has become an essential tool to studybiologicalmolecules, pathways and events in living cells, tissuesand animals.
Meanwhile even the most advanced confocal microscopy can only yield
optical resolution approaching Abbe diffraction limit of ~200 nm. Thisis still larger than many subcellular structures, which are too small tobe resolved in detail.Theselimitations have driven the development ofsuper-resolution opticalimaging methodologies over the past decade.
In stimulated emission depletion (STED) microscopy, the excitation
focus is overlapped by an intense doughnut-shaped spotto instantly
de-excitemarkers from their fluorescent state to the ground stateby
stimulated emission. This effectively eliminates the periphery of the
Point Spread Function (PSF), resulting in a narrower focal region, or
super-resolution. Scanning a sharpened spot through the specimen
renders images with sub-diffraction resolution. Multi-color STED
imaging can present important structural and functional information for

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Conference 8553:
Optics in Health Care and Biomedical Optics V
protein-protein interaction.
In this work, we presenteda dual color, synchronization-free STED
microscopy with a Ti:Sapphire oscillator. The excitation wavelengths
were 532nm and 635nm, respectively. With pump power of 4.6 W andsample irradiance of 310 mW, we achieved super-resolution as high as
71 nm. A series of biological specimens were imaged with our dualcolor STED.

8553-50, Session 11

LOSOM: Phase relief imaging can beachieved with confocal system
Tong Peng, Hao Xie, Yichen Ding, Peking Univ. (China);
Weichao Wang, Shanghai Jiao Tong Univ. (China); Zhiming Li,
Wenzhou Medical College (China); Dayong Jin, Macquarie Univ.
(Australia); Yuanhe Tang, Xi’an Univ. of Technology (China);
Qiushi Ren, Peng Xi, Peking Univ. (China)
Confocal laser scanning microscopy (CLSM) has become one of themost important biomedical research tools today due to its noninvasive
and 3-D abilities.It enablesimaging in living tissue with better resolution
and contrast,and plays a growing role among microscopic techniques
utilized for investigating numerous biological problems.In some cases,
the sample was phase-sensitive, thus we introduce a novel method
named laser oblique scanning optical microscopy (LOSOM) which could
obtain a relief image in transparent sample directly.
Through the LOSOM system, mouse kidney and Hela cells sample wereimaged and 10x,20x and 40x magnify objective imaging results wererealized respectively. Also, we compared the variation of pinhole size
versus imaging result.One major paraments of LOSOM is the distance
between fluorscence medium and the sample.Previously, this distance
was set to 1.2 mm, which is the thickness of the slide.The experimentresult showed that decreasing d can increase the signal level for
LOSOM phase-relief imaging.To study this effect quantitatively, we set
each depth of 0.17mm by designing a stack of hollow coverglasses,andthe result demonstrated the signal strength versus the fluorescencemedium distance.
The LOSOM technic could be used in multiple well plate cellularimaging.In this study, the imaging result of cells with different density
in multiple well plate was attained.We also monitored the cell division
process of onion by LOSOM. Both the results indicated the LOSOM
technic may supply a novel phase sensitive optical image method.

8553-52, Session 11

Design of control system of a real-time
confocal scanning laser microscope
Yaohuan Zhao, Peking Univ. (China); Xusan Yang, Xi’an Univ. ofTechnology (China); Tingting Wang, Peking Univ. (China); Haojie
Li, Xi’an Univ. of Technology (China); Peng Xi, Peking Univ.
(China)Here we used a single Complex Programmable Logic Device togenerate the control and synchronization signals for real time confocal
microscopy. The CPLD can generate the pixel clock, H-Sync, V-Sync,
and the saw-tooth control signal of theoscillating galvanometric mirror.
The CPLD can automatically track the possible drift of the polygon
scanner velocity and adjust H-sync and V-sync signals accordingly
to eliminate the instability of the image. Taking advantage of the
programmable capability of CPLD, our confocal setup can be easily
tuned to work on fast frame rate, or high resolution mode for a variety of
applications.

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8553-53, Session 12

Photo-acoustic excitation and detection ofguided ultrasonic waves in bone samples
covered by a soft coating layer
Zuomin Zhao, Univ. of Oulu (Finland); Petro Moilanen, Univ. of
Jyväskylä (Finland); Pasi Karppinen, Univ. of Helsinki (Finland);Mikko Määttä, Univ. of Oulu (Finland); Timo Karppinen, EdwardHæggström, Univ. of Helsinki (Finland); Jussi Timonen, Univ. of
Jyväskylä (Finland); Risto Myllylä, Univ. of Oulu (Finland)
Photo-acoustic (PA) excitation was combined with skeletal quantitative
ultrasound (QUS) for multi-mode ultrasonic assessment of human longbones. This approach permits tailoring of the ultrasonic excitation anddetection so as to efficiently detect the fundamental flexural guided
wave (FFGW) through a coating of soft tissue. FFGW is a clinically
relevant indicator of cortical thickness. An OPO laser with tunableoptical wavelength, was used to excite a photo-acoustic source inthe shaft of a porcine femur. Ultrasonic signals were detected by apiezoelectric transducer, scanning along the long axis of the bone,
20-50 mm away from the source. Five femurs were measured without
and with a soft coating. The coating was made of an aqueous gelatinintralipid suspension that optically and acoustically mimicked real soft
tissue. An even coating thickness was ensured by using a specificmold. The optical wave length of the source (1250 nm) was tuned
to maximize the amplitude of FFGW excitation at 50 kHz frequency.
The experimentally determined FFGW phase velocity in the uncoatedsamples was consistent with that of the fundamental antisymmetric
Lamb mode (A0). Using appropriate signal processing, FFGW was
also identified in the coated bone samples, this time with a phasevelocity consistent with that theoretically predicted for the first mode of
a fluid-solid bilayer waveguide (BL1). Our results suggest that photoacoustic quantitative ultrasound enables assessment of the thicknesssensitive FFGW in bone through a layer of soft tissue. Photo-acoustic
characterization of the cortical bone thickness may thus become
possible.

8553-54, Session 12

ICG-loaded microbubbles for multimodal
billiary imaging in cholecystectomy
Kinshuk Mitra, The Ohio State Univ. (United States); Shufang
Chang, Chongqing Medical Univ. (China); Scott Melvin M.D.,
The Ohio State Univ. (United States); Ronald X. Xu, The Ohio
State Univ. (United States) and Univ. of Science and Technology
of China (China)
Bile duct injury during a cholecystectomy is an iatrogenic accident
ranking among the leading sources of medical malpractice claims
against surgeons. Intraoperative fluorescence imaging has been used
for real-time non-invasive detection and prevention of bile duct injury.
However, commonly used Indocyanine Green (ICG) is not an ideal
contrast agent for billiary imaging in cholecystectomy. We encapsulated
ICG in PEGylated poly(lactic-co-glycolic acid) (PLGA) microbubbles
by a modified double-emulsion process. Microbubble-assisted billiary
imaging was tested in both tissue simulating phantoms and an ex
vivo tissue model. The tissue simulating phantoms simulated different
surgical scenario and the simulated billiary structures were imaged
by a fluorescence imaging module in a Da Vinci surgical robot. As tothe ex vivo model, liver, gall bladder, common bile duct, and part ofduodenum were dissected freshly from domestic swines. Simultaneous
hyperspectral and fluorescence images were acquired after regional
injection of ICG-loaded microbubbles. Our benchtop and animal tests
showed that ICG-loaded MBs are superior to ICG as a fluorescence
contrast agent for image-guided cholecystectomy. This work was
supported by OSU Center for Minimally Invasive Surgery and the
National Center for Research Resources (NCRR Award Number:UL1RR025755).

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8553-55, Session 12

Multimodal imaging of ischemic wounds
Shiwu Zhang, Univ. of Science and Technology of China (China)
and The Ohio State Univ. (United States); Surya C. Gnyawali,
Jiwei Huang, The Ohio State Univ. (United States); Wenqi
Ren, Univ. of Science and Technology of China (China); Gayle
Gordillo M.D., Chandan Sen, The Ohio State Univ. (UnitedStates); Ronald X. Xu, The Ohio State Univ. (United States) andUniv. of Science and Technology of China (China)
The wound healing process involves the reparative phases ofinflammation, proliferation, and remodeling. Interrupting any of thesephases may result in chronically unhealed wounds, amputation,or even patient death. Quantitative assessment of wound tissue
ischemia, perfusion, and inflammation provides critical information
for appropriate detection, staging, and treatment of chronic wounds.
However, no method is available for noninvasive, simultaneous,and quantitative imaging of these tissue parameters. We integrated
hyperspectral, laser speckle, and thermographic imaging modalities
into a single setup for multimodal assessment of tissue oxygenation,
perfusion, and inflammation characteristics. Advanced algorithms
were developed for accurate reconstruction of wound oxygenation
and appropriate co-registration between different imaging modalities.
The multimodal wound imaging system was validated by two ongoingclinical trials approved by OSU IRB. In one clinical trial, the oxygenationand the perfusion maps of a healthy subject’s upper extremity were
continuously monitored during post occlusive reactive hyperemia andcompared with standard measurements. In the other clinical trial, awound of 3mm in diameter was introduced on a healthy subject’s lower
extremity and the healing process was continuously monitored by themultimodal imaging setup. Our experiments demonstrated the clinicalusability of multimodal wound imaging. This research is sponsored by
National Institute of Standards and Technology (60NANB10D184) andUS Army Medical Research Acquisition Act (W81XWH-11-2-0142).

8553-56, Session 12

Microfabrication of multifunctional
microcapsules for multimodal imaging andimage-guided therapy
Ting Si, Univ. of Science and Technology of China (China); Leilei
Zhang, The Ohio State Univ. (United States); Guangbin Li, Univ.
of Science and Technology of China (China); Ronald X. Xu, The
Ohio State Univ. (United States)
With the recent advances in multimodal imaging and image-guided
therapy, optimizing the design and fabrication of biodegradable
carriers for the delivery of drugs and imaging agents become more andmore important. Multifunctional microcapsules encapsulate several
imaging and therapeutic agents in the same biodegradable carrierfor simultaneous detection and treatment of the diseases. Commonlyused microfabrication processes, such as double emulsion, havemultiple limitations, such as the low encapsulation efficiency and theloss of bioactivity for the encapsulated biological cargos. To overcome
these limitations, we carried out both experimental and theoreticalstudies on coaxial atomization of PLGA microcapsules. The process
combined coaxial electrospray with flow focusing techniques. It wascharacterized by the formation of a coaxial liquid jet in the core of ahigh-speed co-flowing gas stream under an axial electric field and thebreakup of the liquid jet into fine microcapsules. On the experimentalside, the device of the coaxial atomization was developed and tested.
On the theoretical side, a classical normal mode method was used
for instability analysis of the coaxial jet based on the experimental
parameters. The microcapsules were fabricated under different process
conditions. The effects of the process parameters on morphologic andsize characteristics of the microcapsules were studied. The reported
research represents the first step toward quantitative control andoptimization of the coaxial atomization process for the fabrication ofmultifunctional microcapsules in multimodal imaging and image-guided
therapy. This project was sponsored by Natural Science Foundationof China (Project No. 11002139 to Si), National Cancer Institute (Grant
No: R21CA15977 to Xu), and Ohio Lion’s Eye Research Foundation(Fellowship support to Zhang).

8553-57, Session 13

Electromagnetic scattering from biologicaltissueZhisong Tong, Olga Korotkova, Univ. of Miami (United States)
After the development of the optical biomedical technology, theunderlying mechanism for the interaction of light with tissue has been
illustrated that light scattering is not due to discrete particles but
rather to continuous refractive index variation at the microscopic levelin tissue. The proposed mathematical models of the experimentally
fitted spectrum of index inhomogeneities provide a path to investigate
the second-order statistical properties of light on interaction with(propagation through or scattering from) tissue and accelerate theprogress of applications of biomedical optics. For example, with thehelp of models, some studies show that for most biological tissues
the spectrum of the backscattered light is blueshifted with respect
to the spectrum of the incident light, although the overall trend of
red spectral shifting is observed for forward scattering. The above
studies about scattering from tissue are confined to cases in which theincident field is scalar. Hence, it is not possible to account for changes
in those characteristics of the scattered field, which are based on fullelectromagnetic description of stochastic fields, such as, for instance,
the degree of polarization.
Based on the recently built electromagnetic scattering theory, of both
deterministic and random nature, and the relationship between therefractive index correlation function and correlation function of thescattering potential, we carry out the analysis in terms of the crossspectral density matrices of the field scattered from tissue, from which
one can determine its spectral density, spectral degree of polarization,and momentum distribution, etc.

8553-58, Session 13

Optical-tracker-based 3D reconstruction forendoscopic environment
Bo Yang, Ya Zhou, Xiaoming Hu, Qiaona Xing, Junqin Lin,
Beijing Institute of Technology (China)
Endoscopic surgery is increasing for minimally invasive treatment
in recent years. But the conventional two-dimensional endoscope
technique cannot provide three-dimensional information for surgeon.
Lacking depth and other 3D information often made doctors have tocarry out the surgery depending heavily clinical experience. In order tosolve the above described issues, a novel method is proposed.
An 1394 camera is used to capture images. The improved SIFT
algorithm, which is based on SIFT (Scale-invariant feature transform)
and improved according to the characteristics of the endoscopic
images, is applied to extract and match feature points from theendoscopic images. The algorithm can effectively solve the problem
that few feature points can be get from endoscopic images. Afterenough feature points are gotten, the depth information of the matching
points is calculated with the help of an optical tracking system. The
camera is in conjunction with a tracking marker, and the sensor canreceive the infrared light reflected by the marker, therefore the positionand orientation of the endoscope can be obtained easily. From theabove work, a set of point cloud of the structure which needs to bereconstructed is produced .As the discrete 3D points cannot show
the real structure in the field of endoscope vision because the shapeof the surfaces have been lost. How to establish a visual model frompoints cloud is also discussed. In this paper, the Delaunay triangulation
algorithm is used for surface reconstruction. The proposed approach is

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Conference 8553:
Optics in Health Care and Biomedical Optics V
evaluated on sequence digital images gotten from the 1394camera andexperimental results show that the approach is effective.

8553-59, Session 13

Quantification of the scattering andabsorption coefficients of two-layered tissue
models with hyperspectral imaging andMonte Carlo modelingKung-Bin Sung, Hsiang-Chen Pi, Hsi-Hsun Chen, Kuang-Wei
Shih, Yu-Hui Su, Herbert Hsieh, National Taiwan Univ. (Taiwan)
Diffuse reflectance spectroscopy has been increasingly used tononinvasively quantify optical properties of tissue and has the potential
to detect epithelial dysplasia which is a precursor of many cancers. For
stratified squamous epithelial tissues, however, dysplasia-associatedchanges in the epithelium and the underlying stroma may have
opposite effects on reflectance and therefore, reduce the contrast
between normal and dysplastic tissues. We have developed a movable
hyperspectral imaging system with an imaging fiber bundle to measurespatially-resolved reflectance spectra. To improve the sensitivityof measured reflectance to the optical properties of predominately
forward-scattering thin epithelium, we propose to use a beveled fiber
bundle whose end surface is flush with the tissue surface. Comparedto the frequently used probe design in which the source and/or
detection fibers are tilted to increase the overlap between illuminationand collection cones, our proposed probe geometry facilitates
miniaturization of the probe for endoscopic applications. The sensitivityof the proposed probe is analyzed with a scalable Monte Carlo (MC)code that is capable of obtaining a full spectrum in a single MC run. The
MC code is also used in an iterative curve fitting algorithm to extract the
optical properties of two-layered numerical tissue models and tissue
mimicking phantoms. Both the simulations and experiments show
increased sensitivity to epithelial scattering coefficient and improved
accuracy of quantifying the epithelial optical properties. Quantificationof the optical properties of oral mucosa in vivo is demonstrated to prove
the feasibility to improve noninvasive detection of dysplasia in stratified
squamous epithelium.

8553-128, Session 13

Photoacoustic imaging: a potential new tool
for arthritis (Invited Paper)
Xueding Wang, Univ. of Michigan Health System (United States)
The potential application of photoacoustic imaging (PAI) technology todiagnostic imaging and therapeutic monitoring of inflammatory arthritis
has been explored. The feasibility of our bench-top joint imaging
system in delineating soft articular tissue structures in a noninvasive
manner was validated first on rat models and then on human peripheral
joints. Based on the study on a commonly used adjuvant induced
arthritis rat model, the capability of PAI to differentiate arthritic joints
from the normal was also examined. With sufficient imaging depth, PAI
can realize tomographic imaging of a human or a small-animal joint as
a whole organ noninvasively. By presenting additional optical contrast
and tissue functional information such as blood volume and blood
oxygen saturation, PAI may provide a unique opportunity to enable
early diagnosis of inflammatory joint disorders, e.g. rheumatoid arthritis,
and to monitor therapeutic outcomes with improved sensitivity andaccuracy.

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8553-61, Session 14

Enabling technologies towards noninvasive“optical biopsy” at subcellular and molecularlevel (Invited Paper)
Xingde Li, Wenxuan Liang, Johns Hopkins Univ. (United States);
Meredith Akins, The Univ. of Texas Southwestern Medical Ctr.
at Dallas (United States); Jiefeng Xi, Yongping Chen, Qi Mao,
Kristine Glunde, Johns Hopkins Univ. (United States); MingJun Li, Corning Incorporated (United States); Katherine LubyPhelps, Mala Mahendroo, The Univ. of Texas Southwestern
Medical Ctr. at Dallas (United States); Zaver Bhujwalla, Johns
Hopkins Univ. (United States)
This talk will report our recent developments of translational
biophotonics imaging technologies towards visualization of tissue
histology in situ, in vivo and in in real time at subcellular resolution
and with molecular specificity. We will first discuss the nonlinear
optical endomicroscopy technology which enables “optical biopsy”
at true histology resolution. This technology can translate multiphoton
microscopy to clinical practice. Secondly we will present a fast-track
approach for overcoming one key bottleneck in translating opticalmolecular imaging to clinical practice by developing near-infrared
fluorescent nanocapsules using only FDA approved materials.
Representative applications of the reported technologies will bepresented.

8553-62, Session 14

Sophisticated model of the human eye forthe mathcing and the analysis of vision
power variations
between the cataract intraocular lens andcorneal after refractive surgery
Chung-Jen Ou, Hsiuping Institute of Technology (Taiwan); HanYin Sun, Chung Shan Medical Univ. (Taiwan)
At the present time, the clinical physicians encountered an argument:
patient proceed the cornea-reshape surgery like Orthokeratology, withcataract and glaucoma, sometimes do not currently know how to matchthe artificial lens to achieve optimal vision qualities. In addition, notevery hospital or local doctor owns a high wavefront detection systemwith optical/mechanical simulation experiences that can simultaneously
measure wavefront and predict the possible consequences caused bysuch surgery uncertainty. In this report, we discuss the formulae for the
doctor about the matching between the artificial lens surgery with thecataract and glaucoma. Software simulation on the constructed human
eye and the wavefront detection is the key to complete this task.
In conclusion, we introduce simple components to correct higher
order aberration of the human eye with these deceases and thesurgery treatment. Although we realize and expect that these simple
components cannot eliminate all the aberration of the patients however, they can provide necessary information to a portable device
and send it back to the simulator to understand the present situation of
the patients for the next step diagnosis.

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8553-64, Session 14

Investigating the backscatteringcharacteristics of individual normal andcancerous cells based on experimentally
determined three-dimensional refractive
index distributions
Jing-Wei Su, Wei-Chen Hsu, Chih-Chiang Chang, Kung-Bin
Sung, National Taiwan Univ. (Taiwan)
During dysplastic progression of epithelial tissues it is believed thatepithelial cells introduce changes of sub-cellular structures which alter
the light scattering properties of the cells. In particular, backscattering
properties are sensitive to subtle changes in the sub-cellular structuresof the cells. The finite-difference time-domain (FDTD) simulation tool
can be used to investigate the spectral and angular backscatteringcharacteristics of cells due to structural changes, thereby increasing
the understanding of the changes in light scattering properties
associated with dysplasia. However, the quantitative investigation of
three-dimensional (3D) sub-cellular structures of living cells has been
limited by the lack of appropriate microscopy techniques. Recently,
we developed digital holographic microtomography (DHµT) based on
arbitrary phase-shifting interferometry in Mach-Zehnder configurationand optical diffraction tomography algorithms to determine the 3D
quantitative refractive index (RI) distributions of living cells. In thisstudy, we utilize the DHµT to quantify the RI distributions of normal andcancerous epithelial cells of skin and oral cavity. We then investigate
the spectral and angular backscattering characteristics of the cells
using the measured 3D RI distributions in FDTD simulations. The
preliminary statistical results show that cancerous cells present higher
average values of nuclear and nucleolar RI and a higher standard
deviation of cytoplasmic RI than normal cells. The backscattering crosssection of the cancerous cells is significantly higher than that of thenormal cells, mainly attributed to the higher average RI value and moreheterogeneous sub-cellular structures of the cancerous cells.

8553-65, Session 14

Cost-effective approaches for highresolution bioimaging by time-stretchedconfocal microscopy at 1um
Terence Wong, Yi Qiu, Andy K. S. Lau, JingJiang Xu, Antony C.
S. Chan, Kenneth K. Wong, Kevin K. Tsia, The Univ. of Hong
Kong (Hong Kong, China)
Optical imaging based on time-stretched process has recently been
proven as a powerful tool for delivering ultra-high frame rate (> 1MHz)
which is not achievable by the conventional image sensors. Together
with the capability of optical image amplification for overcoming thetrade-off between detection sensitivity and speed, this new imaging
modality is particularly valuable in high-throughput biomedical
diagnostic practice, e.g. imaging flow cytometry. The ultra-high frame
rate in time-stretched imaging is attained by two key enabling elements:
dispersive fiber providing the time-stretched process via groupvelocity-dispersion (GVD), and electronic digitizer. It is well-known thatmany biophotonic applications favor the spectral window of ~1um.
However, reasonably high GVD (> 0.1 ns/nm) in this range can only beachieved by using specialty single-mode fiber (SMF) at 1um. Moreover,the ultrafast detection has to rely on the state-of-the-art digitizer withsignificantly wide-bandwidth and high sampling rate (e.g. > 10GHz,
40GS/s). These stringent requirements imply the prohibitively high-costof the system and hinder its practical use in biomedical diagnostics.
We here demonstrate two cost-effective approaches for realizingtime-stretched confocal microscopy at 1um: (i) using the standard
telecommunication SMF (e.g. SMF28) to act as a few-mode fiber (FMF)
at 1um for the time-stretch process, and (ii) implementing the pixel
super-resolution (SR) algorithm to restore the high-resolution image
when using a lower bandwidth digitizer. By using a FMF (with a GVD of> 0.2ns/nm) and a modified pixel-SR algorithm, we can achieve timestretched confocal microscopy at 1um with cellular resolution (~ 3um) ata frame rate 1.25 MHz.

8553-66, Session 14

Hilbert transform imaging in phase object
detection
Shouyu Wang, Liang Xue, Jiancheng Lai, Yang Song, Zhenhua
Li, Nanjing Univ. of Science and Technology (China)
Imaging of phase objects such as biological samples owns greatsignificance in qualitative and quantitative detecion. Since many
biological cells act as phase objects since they owns negligible
absorption and scattering effects, traditional bright field and dark
field microscopy could not clearly show the characteristics of thesesamples. Many other methods as phase contrast (PC) and differential
interferometric contrast (DIC) are applied to reveal the phase
distributions. Here, a new method named as Hilbert Transform Imaging(HTI) is proposed for phase object imaging. Compared to PC and
DIC methods, HTI focuses on edge information of the phase object
in order to reveal the phase changing of the phase distribution. The
enhanced edge in Hilbert Transform Imaging could easily determine
the shape of the phase samples. Besides, Hilbert Transform Imaging
is easy to realize only with 4f system and waveplates. Combining
Hilbert Transform Imaging with microscopy, the edge and shape of thebiological samples could be demonstrated. Hilbert Transform Imaging
is shown to provide highly efficient in biological samples detection for
disease diagnosis in vivo and in vitro.

8553-67, Session 15

Fast reconstruction of Raman spectra fromnarrow-band measurements based on
Wiener estimation
Shuo Chen, Yihong Ong, Quan Liu, Nanyang Technological
Univ. (Singapore)
Raman spectroscopy has demonstrated great potential in the study of
biological molecules in a variety of biomedical applications. But slow
data acquisition due to weak Raman signals from these molecules has
prevented its wide use especially in an imaging setup. We propose anovel method to reconstruct the entire Raman spectrum from a few
narrow-band measurements based on Wiener estimation. This method
consists of a calibration step and a test step. In the calibration step,
both the Raman spectra and the narrow-band measurements are
acquired from given calibration samples and a Wiener matrix is createdout of two sets of data. The Wiener matrix is then used in the test step
to reconstruct the Raman spectrum from narrow-band measurements
acquired on an unknown sample. This method has been tested on
Raman spectra from individual cells. In addition to the fast speed,
this method has also shown high accuracy in reconstructed Raman
spectra. This method represents a new direction to speed up Raman
data acquisition in an imaging setup to investigate fast changing
phenomena.

8553-68, Session 15

Evaluation of human dentine
demineralization of yellow race by Raman
spectraZhenlin Zhan, Fujian Normal Univ. (China); Wenqing Guo,
Haishan Liu, Xianzeng Zhang, Shusen Xie, Fujian Normal Univ
(China)Dental caries, also known as tooth decay or a cavity, is the most

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Conference 8553:
Optics in Health Care and Biomedical Optics V
prevalent chronic disease in dentistry, which is seriously threatening
human oral health. Generally, a tooth is in a constant state of backand-forth demineralization and remineralization between the tooth andsurrounding saliva. When demineralization exceeds saliva and otherremineralization factors, the mineral content is progressively broken
down, producing dental caries. If carious lesions could be detected
early enough, intervention methods can be applied to reverse thecaries process. In this study, the demineralization status at different
acid-etch time is monitoring by Raman spectra. Human molar in vitroof yellow race is used in the study and immersed in 0.3% citric acidto simulate the oral natural demineralization. According to acid-etch
time, samples are divided into four group: I:5 min, II:10 min, III:20 min
and IV:40 min. The normal untreated specimen is set as control group.
Raman spectra before and after treatment are measured and analysed.
The result shows that Raman spectroscopy could be efficiently used
to monitor the demineralization status of human dentin. There is no
new constituent formed after demineralization. The peak intensity of
inorganic constituent decreases with the increase of acid-etch time,
while the trend of organic constituent is opposite. For 10 min, 40 min
and control group, there are statistical difference between any twogroups.

8553-69, Session 15

Assessment of skin flap viability using
visible diffuse reflectance spectroscopy andautofluorescence spectroscopy
Caigang Zhu, Shuo Chen, Quan Liu, Nanyang Technological
Univ. (Singapore)
The accurate assessment of skin flap viability is critical to shortening
the period of inconvenient immobilization and saving medical costwithout compromising the success rate of flap transfer in plastic
surgery. Visible diffuse reflectance and autofluorescence spectroscopy
have shown excellent potential for assessing tissue viability separately.
However, they have not been used in the characterization of skin flap
viability at the same time to our best knowledge. In this study, we
performed both diffuse reflectance spectroscopy and autofluorescence
spectroscopy on a reversed MacFarlane rat dorsal skin flap modelin an attempt to identify the additional value of autofluorescence
spectroscopy to the assessment of flap viability. Diffuse reflectance andautofluorescence spectra (excited by 405 nm laser light) were measured
every four hours over 72 hours after the creation of dorsal flap. The
trend in total hemoglobin concentration and blood oxygenation overtime estimated from diffuse reflectance spectra agreed with the
published data. The trends in total hemoglobin concentration overtime estimated from autofluorescence spectra in both survived anddied flaps were consistent with those obtained from diffuse reflectancespectra. The shape of fluorescence spectra from flaps that eventuallydied changed dramatically in the first a few hours. In particular, thesingle fluorescence peak at around 500 nm was blue shifted and thewidth of the peak decreased in died flaps. The analysis of intrinsic
fluorescence indicates that these observations could be attributed
to the changes in the concentrations of tissue fluorophores. Our
result suggests that fluorescence spectroscopy could be a valuable
complement to diffuse reflectance spectroscopy for the assessment offlap viability.

8553-70, Session 15

Characterization and differentiation normal
and abnormal semen samples using microRaman spectroscopy
Zufang Huang, Xiwen Chen, Yongzeng Li, Shangyuan Feng,
Rong Chen, Fujian Normal Univ. (China)
Male infertility has become a social and medical problem with roughestimation showing that over 10% of male are diagnosed with infertility.

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Drop in semen volume and quality has been confirmed with factors
such as radiation, food products and drugs. In clinical, the mostcommonly used method: computer-assisted semen analysis (CASA)
has been considered inaccurate and imprecise. Therefore, developmentof methods that allow for providing morphological and biochemical
information of semen samples from cellular or sub-cellular level withoutcausing potential damage is attractive. In our study, a fast and reliable
semen sample preparation method is proposed, and then microRaman spectroscopy was employed to characterize and differentiate
the normal and abnormal semen samples based on their different
biochemical components which reflect in their specific Raman spectra
differences. As semen consists of two parts, the cellular and noncellularparts, we focused on using micro-Raman spectroscopy combined withmultivariate analytical method (PCA-LDA) to characterize and classify
the morphologically normal and abnormal-shaped human sperm cells,
meanwhile, seminal plasma which acts as the nutritive and protective
medium for sperm cells were separated and tested between normalgroup and abnormal group. Our preliminary results demonstrate that as
a powerful tool, micro-Raman spectroscopy has the potential of being
used to characterize and classify semen samples.

8553-71, Session 15

Brain cancer probed by native fluorescenceand stokes shift spectroscopy
Yan Zhou M.D., The General Hospital of the Air Force, PLA(China); Cheng-Hui Liu, The City College of New York CUNY
(United States); Yong He, Beijing Normal Univ. (China); Yi Sun,
The City College of New York (United States); Yang Pu, The
City College of New York CUNY (United States); Qingbo Li,
Wei Wang, BeiHang Univ. (China); Robert R. Alfano, The City
College of New York CUNY (United States)
Optical biopsy spectroscopy has many advantages; it is less invasive,
rapid, real time and can be potential used in situ diagnosis. This
presentation focuses on the diagnosis of human brain cancer in vitro.
The native fluorescence, stokes shift and excitation spectra were
measured in malignant, benign, normal meningeal tissues and acoustic
neuroma benign tissues within wide wavelengths range. The study was
performed using PerkinElmer LS 55 fluorescence Spectrometer. Ninety
one spectra of fluorescence and Stokes shift were investigated. The
fluorescence spectra of the meningeal brain tissues displayed different
chromophoric molecules such as ceroids and lipofuscin lipopigmentsthat were identified under the excitation with UV to visible wavelength
range.
The basic biochemical component analysis model (BBCA) and a set ofalgorithms were used to analyze the spectra. Our preliminary analysesof fluorescence spectra showed, for the first time, the relative content
of tryptophan and flavin increased, and those of fat, collagen type I
and hemoglobin decreased in cancerous tissue compared to normal
brain tissues. The ratios of intensity at peak position in the spectra ofboth fluorescence and stokes shift were found to be different between
cancerous and normal tissues. The criteria for distinguishing brain
diseases were established. For the typical fluorescence spectra, ratio of
I 340nm over I 440nm is larger than 18.50 in meninges cancer tissues
while for the typical stokes shift spectra, the values of ratio of I290nm toI341nm is larger than 8.2 in cancer meninges tissues. The database forclinical diagnosis of brain is extended and will be presented.

8553-72, Session 15

Wide bandwidth absorption/scattering
spectroscopy for biomedical and industrial
applications
Dmitry Khoptyar, Lund Univ. (Sweden); Otto H. A. Nielsen,
Technical Univ. of Denmark (Denmark); Arman Ahamed Subash,

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Optics in Health Care and Biomedical Optics V
Lund Univ. (Sweden); Muhammad Saleem, National Instituteof Lasers and Optronics (Pakistan); Stefan Andersson-Engels,
Lund Univ. (Sweden)
Diffuse optical spectroscopy (DOS) is an important component ofbiophotonics toolbox that readily finds its applications in biomedical
optics, optical diagnostics and treatments monitoring. DOS is also
is highly actual in numerous industrial applications such as new
product R&D, fabrication process monitoring and quality control. The
further advance in applications urges development of the novel DOS
instrumentation capable to deliver highly accurate and exhaustive
spectroscopic data at high speeds relevant for such time-criticalapplication as real-time treatment response monitoring or in line
process control. Recent progress in source and detector technology
enables us to design broadband photon time of flight (PTOF)
spectrometer for turbid media that is capable to deliver continuous
absorption/scattering spectra over visible and close NIR range. In ourcontribution we report on further progress of instrument performance.
By upgrading the source we have recently further extended the spectral
range of our instrument which is now stretches form below 500nm up
to 1400nm. This facilitates advance structural sample characterization
due to extended scattering data available. Implementation of advanced
stabilization techniques enables us to attain superior precession
in measurements of absorption and scattering coefficient down to
0.5%. Furthermore recent upgrade enables fully automated spectra
acquisition at the speed appropriate for real-time industrial andbiomedical applications. We illustrate outstanding performance of our
instrument by presenting our new results on highly accurate quantitative
analysis of pharmaceutical and for industrial control in dairy fabrication.
Moreover we also report on application of the spectrometer tomonitoring of cardio-vascular activity in real patients.

8553-74, Session 16

Rabbit electroretinograms evoked by
632.8nm laser flash stimuli
Zai-Fu Yang, Bo-Lin Guan, Jiarui Wang, Beijing Institute ofRadiation Medicine (China); Hongxia Chen, Chinese PLA
General Hospital (China); Xiaona Zhang, Wen-Yuan Zhang,
Jinggeng Yang, Beijing Institute of Radiation Medicine (China)
The flash electroretinography is a standard electrophysiological method
and widely employed in basic research and ophthalmology clinics,of which the stimulus is usually white flash from dome stimulator.
However, little is known about the electroretinograms(ERGs) evokedby monochromatic laser flash stimuli. The goal of this research effort isto quantify the ERGs of dark-adapted New Zealand rabbits evoked by
He-Ne laser flash with wavelength 632.8nm. The flash field was either a
Maxwellian viewing disc with angular subtense of 20.2, 13.3, 8.5 degree
or a collimated beam with 3mm beam diameter at cornea. The stimulus
duration was 22ms, 70ms and 220ms. The energy per laser flash varied
from 0.5nJ through 0.5mJ. Under the condition of stimulus duration
20ms and angular subtense 20.2 degree, the ERG of New Zealandrabbit was compared with that of Chinchilla gray rabbit. Results showedthat the amplitude of b- and a-wave increased, while the implicit timedecreased with the increase of laser energy. The b-wave met a platform
when the laser energy was high enough. The comparison of b-wave
amplitude between different angular subtenses showed that the ERG
is dominated by the retinal total energy but not radiant exposure. The
comparison between different stimulus durations showed that the
ERG is dominated by the retinal laser power and the b-wave amplitudedecreases with the increase of stimulus duration. The comparison
between pigmented and non-pigmented rabbits showed that the later ismore sensitive and the threshold energy for b-wave excitation is about
10 times lower than the former.

8553-75, Session 16

The threshold of vapor channel formation inwater induced by pulsed CO2 laser
Wenqing Guo, Xianzeng Zhang, Zhenlin Zhan, Shusen Xie,
Fujian Normal Univ. (China)
Water plays an important role in laser ablation. There are two main
explanations of laser-water interaction: hydrokinetic effect and vapor
channel. The two explanations are reasonable in some way, but they
can’t explain the mechanism of laser-water interaction completely. In
the study, the dynamic process of vapor channel in static water layer
induced by pulsed CO2 laser was monitored by high-speed camera.
The wavelength of pulsed CO2 laser (Sharplan 30C) is 10.64um,
power ranges from 1W to 30W and pulse repetition rate is 60Hz. The
maximum frame rate of high-speed camera is 150000fps. Based on
the processing of the photographs attained by high-speed camera, thethreshold of vapor channel formation was determined. The study of themechanism of laser-water interaction will improve the application oflaser in surgery, laser machining and other fields.

8553-76, Session 16

Mechanisms of interaction between very
high-frequency photoacoustic waves andthe skinGonçalo Sá, Carlos Serpa, Luis G. Arnaut, Univ. de Coimbra(Portugal)
The enhancement of transdermal drug delivery with ultrasounds isinterpreted on the basis of the following mechanisms: 1) temperature
increase caused by heat release, 2) cavitation associated with thecreation and collapse of microbubbles, 3) microstreaming definedas circulating fluid flow accelerated by oscillating microbubbles, 4)radiation pressure due to the force exerted by the sound wave.
Ultrasonic waves with the center frequencies employed in sonophoresis
and ultrasonography (typically from 0.2 to 20 MHz) interact weakly withtissues. The heat dissipated leads to a temperature increase that isquantified by the thermal index of ultrasound. The onset of cavitation,and hence of microstreaming, is characterized by the mechanicalindex of ultrasound. The role of temperature, transient cavitationand microstreaming in permeabilizing the skin has been thoroughly
discussed in the literature. On the other hand, the radiation pressure
mechanism was previously disregarded on the basis of: i) calculations
on the forces exerted by pressures of millibar amplitudes, 2) the
small pressure gradients generated by ultrasound across the stratum
corneum (the typical wavelength of ultrasound at 1 MHz is 150 µm
whereas the thickness of the stratum corneum is 15 µm).
In this work we employ photoacoustic waves with 1 MPa amplitudeand center frequencies of 100 MHz to transiently perturb the stratum
corneum. We show that the dynamic acoustic radiation force
mechanism can explain the perturbation induced by the photoacoustic
waves. Indeed, 15 bar pressure gradients across 5 corneocytes(approx. 5 µm wide) are expected to perturb their structure.

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Conference 8554:
Quantum and Nonlinear Optics II
Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8554 Quantum and Nonlinear Optics II

8554-1, Session 1

Scalable quantum information processing
with atoms and photons
Jianwei Pan, Univ. of Science and Technology of China (China)
No Abstract Available

8554-2, Session 1

Balanced-heterodyne detection of opticalsqueezing (Invited Paper)
Sheng Feng, Chenggang Shao, Huazhong Univ. of Science andTechnology (China)
As part of an effort to make use of optical squeezing for detection of
sub-shot-noise optical signals, we study the balanced-heterodyne
scheme, for which the corresponding spectral density of thephotocurrent fluctuations produced at the output of the photo-detector
is calculated as the Fourier transform of their autocorrelation function.
We show that, for maximal signal-to-noise ratio enhancement by useof squeezed states of light, an optical signal to be measured in thisscheme must be carried in the squeezed quadrature of the carrier field.
Most importantly, our analysis reveals that ``the additional heterodyne
noise’’ can be eliminated in balanced-heterodyne detection under someexperimental conditions and, from this, we discuss how this scheme
may be exploited in gravitational-wave searching.

8554-3, Session 1

Quantum election based on distributed
schemeRui-Rui Zhou, Li Yang, Institute of Information Engineering ofChinese Academy of Sciences (China)
We have presented an unconditionally secure authority-certified
quantum election scheme based on anonymous quantum key
distribution, the scheme ensures the completeness, soundness, privacy,
eligibility, unreusability, fairness and verifiability of a large scale election.
The voting administrator and the counter are independent parties
and we assume they are semi-honest in the scheme. However, thiscondition is difficult to achieve in practice, because there is no efficient
way to guarantee that the two parties will not cooperate forever, and amalicious voting administrator may personate the eligible voter to vote.
In view of this, we propose a distributed election scheme, in which thevoting administrator is made up by two parties who cannot cooperate
up to cheat within a certain period of time, thus it solves the dispute
between the voting administrator and the voters. In addition, we usean”identity exchange”scheme to conceal the identity of voters. Whilethe election is completed, nobody except the voter himself can match
him with his ballot even if the voting administrator and the countercollaborate up to do so. The scheme can also work well with noisy
quantum channels and the only condition is that the entities in thescheme cannot cooperate with a certain period of time, this require isreasonable and not difficult to achieve in practice.

8554-4, Session 1

A quantum enhanced lidar with polarized
photons
Xiaofei Wang, Bing Zhu, Univ. of Science and Technology ofChina (China)
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Electromagnetic waves with polarization modulation are widely utilizedin Radar and Lidar, and they often depend on classical mechanics
and Shannon information theory. As such, quantum effects can’t bedirectly dealt with nor used. Since quantum effects can bring quantum
positioning system, interferometric quantum radar, quantum illuminationand so on. This paper designs a quantum enhanced lidar whichtransmits polarized photons, and the processes are calculated by
the laws of quantum electrodynamics.The polarized photons process
photon-atom scattering on the target’s surface, and this theoreticallybrings new results to the classical system: polarized quantum enhanced
lidar can gain more targets’ characters. In this paper we reportsimulations and experimental results. The transmitter combines two
sets of orthogonal 653nm linearly polarized beams: 00,900,450 and
1350,then attenuate them to photons. The detecting photons and thetargets 30 meters away interact in the free space, and different target’s
characters feed back by the scattered photons. This paper designs apolarized quantum demodulator which makes up of polarizing beam
splitter and photon counters to acquire the above feedback. Transmitterand Receiver synchronize their clocks to suppress the noise by the time
filtering.The experiments verify that our regime can apperceive different
targets and amends the classical system. As such this polarized
quantum enhanced lidar gets the similar transmitter and receiver to theBB84 quantum key distribution system, for some targets, our system
can achieve utterly confidential target detection in theory.

8554-5, Session 1

Measurement of transition frequencies andmagnetic field amplitudes via beating signals
in an asymmetric procedure of light storage
and retrieval
Qianqian Bao, Bo Fang, Junyan Gao, Jilin Univ. (China)
Coherent control of light propagation dynamics has been greatly
investigated in the past few decades according to its important
applications in reversible storage and efficient processing of photonic
quantum information. It is interesting to note that beating signals
have been observed recently as a manifestation of the preserved
phase information during light storage and retrieval Moreover, suchinterferometric beating observed in a light storage experiment isessential due to its potential application in the fast quantum-limited
measurements of atomic transition frequencies and magnetic-field
amplitudes. To this end, we present a novel scheme for the dynamic
generation and flexible manipulation of beating signals in a tripod-typeatomic sample via an asymmetric light storage and retrieval techniquebased on electromagnetically induced transparency (EIT). In addition,
we have demonstrated by numerical calculations and analyzed theefficient scheme in the polariton picture for the beating signals.
Furthermore, we interpret how to infer the frequency difference, therelative phase, and their stabilities from the beating signals imposed ona weak probe field. Particularly, we demonstrate that the amplitude B ofa magnetic field can be determined from such interferometric beating
signals. We expect that our numerical findings could be explored todevise novel photonic devices for manipulating a quantum light field,
even at the single-photon level.

8554-6, Session 2

Confined indirect excitons in one andtwo dimensional magnetic lattices: BoseHubbard model and beyond
Ahmed M. Abdelrahman, Byoung Seung Ham, Inha Univ.
(Korea, Republic of)

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Quantum and Nonlinear Optics II
Confined indirect excitons in one and two-dimensional magnetic
lattices are promoted to simulate condensed matter systems. Sufficientevaporative cooling allows the trapped clouds of indirect excitons toexperience the Bose-Einstein condensation phase transition and exhibit
a long-range spatial coherence which causes an inherited phase-locked
across all of the coupled sites (single traps). Using an external magnetic
bias field a mutual tunneling can be adiabatically exchanged betweensites in which case the underline physics of Bose-Hubbard model canbe explored such as Mott-insulator and Josephson Effect.

8554-7, Session 2

Towards coherent manipulation of theground states of single cesium atom
confined in a microscopic far-off-resonanceoptical dipole trap
Wenting Diao, Jun He, Bei Liu, Tiancai Zhang, Junmin Wang,
Shanxi Univ. (China)
Coherent control of ground states of single atoms has attracted muchattention as it can be used as single quantum bit (qubit). We haveefficiently loaded single cesium (Cs) atoms from a large-magneticgradient magneto-optical trap (MOT) into a microscopic far-offresonance optical dipole trap (FORT) which is formed by a stronglyfocused single-frequency 1064nm laser beam with the waist radiusof 2.3um. The trapping lifetime of single Cs atoms in the FORT canbe extended to ~ 130 s by improving the background pressure andadopting a proper laser cooling phase. The relaxation time of hyperfine
ground state of single Cs atoms is measured to be ~ 4.6 s. The qubit
can be encoded into the two clock states (|6S_1/2 F=4, m_F=0> and|6S_1/2 F=3, m_F=0>) of single cesium atom. To realize scalability, we
will construct a 2D array of microscopic dipole traps by using of 2D
arrays of micro lenses.
In the coherent manipulation process of single atom, two phase-locked
laser beams with frequency difference of 9.192GHz (hyperfine splitting
in cesium ground state) are used to drive the STIRAP in a Lambdatype three-level system consists of cesium |6S_1/2 F=4, m_F=0> and|6S_1/2 F=3, m_F=0> long-lived ground clock states and 6P_3/2 (Fe=4)
excited state with the single photon red detuning of ~ 50GHz. The twolaser beams is generated by optical injection of an 852-nm extendedcavity diode laser (master laser) to lock the +1-order sideband of a
9-GHz current-modulated diode laser (slave laser). The relative linewidth of two phase-locked laser beams has measured ~ 1 Hz by beatnote experiment, which is limited by the resolution bandwidth (RBW) of
the radio-frequency spectrum analyzer.
Our ongoing work is preparing the single atom into an arbitrary coherent
superposition states of cesium |6S_1/2 F=4, m_F=0> and |6S_1/2 F=3,
m_F=0> long-lived ground clock states, measuring the Rabi oscillationof coherent manipulation of single atom, and evaluating de-coherencetime of atomic qubit.

8554-8, Session 2

Strong coupling of single cesium atoms
with TEM_00 and TEM_10 modes of a highfinesse optical microcavity and applications
Junmin Wang, Pengfei Zhang, Gang Li, Tiancai Zhang, Shanxi
Univ. (China)
In our experiment, strong coupling of single cesium atoms with a highfinesse optical cavity (the finesse is ~ 3.3 x 10^5 and the cavity length is~ 86 um) has been realized in both cases of using TEM_00 and TEM_10
modes. The typical parameters for these two cases are (g_00,k,gamma)= 2Pi x (23.9, 2.6, 2.6) MHz and (g_10,k,gamma) = 2Pi x (20.5, 2.6, 2.6)
MHz, respectively. Obviously the coupling factors (g00 and g10) arealmost one-magnitude larger than the cavity field decay rate (k) andthe transverse atomic dipole decay rate (gamma), therefore our systemreaches exactly the strong coupling regime. It means that even only
one atom or one photon entering into or escaping from the cavity willcompletely modify the state of whole atom-cavity system.
Adopting strong coupling of single atoms with TEM_00 cavity modethe effective temperature of laser-cooled atoms, which are prepared ina magneto-optical trap (MOT) located just ~ 5 mm above the microcavity, can be determined. The vacuum Rabi splitting is measured whencold atoms freely fall from MOT due to gravity and pass through themicro-cavity. From the probe laser’s transmission signals of the atomcavity system the velocity with which individual atom passed throughthe cavity is obtained. Then the effective temperature is extracted after
averaging many single-atom measurements statistically and fitting
experimental data theoretically. Obviously this is an alternative method
for measuring the cold atoms’ temperature.
Employing strong coupling of single atoms with the tilted TEM_10 cavity
mode the trajectories of individual atoms, which freely fall and verticallypass through the anti-node plane of the cavity, can be precisely tracked.
Thanks to the tilted TEM_10 mode, instead of TEM_00 mode, thedegeneracy of symmetric trajectories is eliminated completely. Under
the low-field approximation the trajectories of individual atoms passing
through the cavity are almost straight lines along vertical direction. This
allows us to more precisely determine individual atom’s trajectory along
the off-axis horizontal direction. Typical spatial resolution of 100 nm is
obtained in a measurement time of 10 us, and it is much better thanprevious measurements.

8554-9, Session 3

Einstein-Podolsky-Rosen entanglement
and steering in two-well BEC ground states(Invited Paper)
Qiongyi He, Peking Univ. (China) and Swinburne Univ. ofTechnology (Australia); Peter D. Drummond, Swinburne Univ. ofTechnology (Australia); Murray Olsen, The Univ. of Queensland(Australia); Margaret Reid, Swinburne Univ. of Technology(Australia)
We consider how to generate and detect Einstein-Podolsky-Rosen(EPR) entanglement and the steering paradox between groups of
atoms in two separated potential wells in a Bose-Einstein condensate(BEC). We present experimental criteria for this form of entanglement,
and propose experimental strategies for detecting entanglement using
two or four-mode ground states. These approaches use spatial and/or internal modes. We also present higher order criteria that act as
signatures to detect the multiparticle entanglement present in thissystem. We point out the difference between spatial entanglement
using separated detectors, and other types of entanglement that do not
require spatial separation. The four-mode approach with two spatial andtwo internal modes results in an entanglement signature with spatiallyseparated detectors, conceptually similar to the original EPR paradox.
In addition, we also develop the concept of genuine N?partite
Einstein-Podolsky-Rosen (EPR) steering. This nonlocality is realized
as a multiparty EPR paradox, and is the key ingredient for quantum
secret sharing. Useful properties emerge that are not guaranteed for
genuine multipartite entangled states. We derive criteria to demonstrate
multipartite EPR steering for GHZ, W and Gaussian continuous variable(CV) states in experiments.

8554-10, Session 3

Theory of quantum entanglement based on
surface phonon polaritons in condensed
matter systems
Yang Ming, Zijian Wu, Xikui Hu, Fei Xu, Yanqing Lu, Nanjing
Univ. (China)

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Conference 8554:
Quantum and Nonlinear Optics II
Condensed matter systems are potential candidates to realize theintegration of quantum information circuits. Surface phonon polariton(SPhP) is a special propagation mode in condensed matter systems.In
this work, we present a theoretical study of quantum entanglement incondensed matter systems. Firstly, to describe the quantum charactersand relative evolution processes of LRSPhP, a canonical quantization
procedure is taken. Based on the quantization formulation of the
LRSPhP mode, we could obtain the effective interaction Hamiltonianof the coupling process between entangled photons and entangled
LRSPhPs. Utilizing the interaction Hamiltonian and the perturbation
approximation of the evolution equation, we obtain the state vectorof the entangled LRSPhP modes. The entanglement performance ofthe system is discussed. To a further investigation of our system, thecoupling process of entangled photons and entangled LRSPhP is
described through the mechanics approach. Finally, the correlation of
our system is examined. We aim to providing a whole set of theories to
describe entanglement of surface phonon polariton, which may possesshuge potential for realizing integrated quantum circuits in condensed
matter systems.

8554-11, Session 3

Generation of frequency de-correlated
photon pairs by using photonic crystal fiber
Liang Cui, Ningbo Zhao, Kang Gao, Xiaoying Li, Tianjin Univ.
(China)For quantum information processing and quantum statecharacterization involving quantum interference among multiple
sources, frequency de-correlated photon pairs, which can be employed
to realize heralded single photon in pure state, are highly desirable.
Recently, there are growing interests in generating frequency decorrelated photon pairs via pulse pumped spontaneous four wave
mixing in photonic crystal fibers (PCF).
In this paper, after illustrating why the measurable quantity--intensity
correlation function g^(2) of individual signal (idler) photons can beused to characterize the frequency correlation of photon pairs, we firstnumerically investigate the dependence of g^(2) upon the higher orderdispersion of PCF, the intrinsic sinc oscillation of the phase matching
function and the chirp of pump pulse. We then accordingly optimize
the experimental parameters and experimentally generate photon pairs
with minimized frequency correlation. For filter free case, the maximumg^(2) of the individual signal photons we obtained is 1.78 ± 0.02,
showing the photon pairs are approximately frequency de-correlated.
Moreover, based on the photon pairs, we also demonstrate a heralded
single photon source with low noise and approximate single-mode
characteristic, whose the heralding efficiency is about 86%, and theintensity correlation of the heralded (signal) photons is suppressed bya factor of more than 80 relative to the classical Poissonian light limit.
Although the experimentally measured g^(2) is less than the calculated
result due to the inhomogeneity of the PCF, the experimental results
qualitatively agree with numerical simulations.

8554-12, Session 3

Entanglement storage with self-assembled
quantum dot devices
Qin Wang, Nanjing Univ. of Posts and Telecommunications(China); Yongsheng Zhang, Univ. of Science and Technology ofChina (China)
We give a proposal on using self-assembled single-quantum-dot
devices to store entangled photon pairs and retrieve them on demand.
We also analyze the possibility of realizing it with current technology.
In this scheme, the quantum information can be stored by excitinga coherent superposition of exciton states corresponding to the twopolarizations and then mapping the electronic part of that state to
the nuclear ensemble, so as to realize a quantum storage in nuclear

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ensembles. Finally, the quantum information can be retrieved on
demand with the reversed process. We also evaluate the storage
fidelity with imperfect experimental conditions and demonstrate that aquite high storage fidelity can still be obtained. Therefore, the proposal
may be a feasible avenue in processing entanglement storage in thenear future. The scheme is an alternative to the research on utilizing
atomic ensembles to realize quantum repeater which is highly desiredin quantum communication. Besides, because of the good scalability
in self-assembled quantum dot devices, it also has a promising
implementation in the field of quantum computing.

8554-13, Session 4

Quantum light sources based on third-ordernonlinear waveguides (Invited Paper)
Wei Zhang, Qiang Zhou, Yidong Huang, Jiangde Peng, Tsinghua
Univ. (China)
Recently, the concept of quantum engineering was proposed andaccepted by the academia, driving by the efforts to develop quantum
information applications for real use. Many mature technologies
traditionally used in laboratories are difficult to meet the requirementsof engineering. Hence, new realization schemes of quantum information
functions compatible with today’s engineering technologies attract
much attention. The researches of practical quantum light sources are
representative in this direction.
Traditionally, correlated/entangled photon pairs are generated byspontaneous parametric down-conversion (SPDC) in crystals withsecond-order nonlinearities, which have been widely used in various
quantum optics experiments. However, its experimental setup is basedon free space optics, which has several drawbacks from the view ofengineering, including its high requirement on fine optical alignmentand stability of experimental condition, large capacity and unwieldiness,and limited photon collection efficiency in long distance transmission.
Spontaneous four-wave mixing (SFWM) in third-order nonlinear medium
provides another way to generate correlated/entangled photon pairs,
which can be realized in waveguides widely used in optoelectronics andoptical communication, showing great potentials in developing practicalquantum light source devices.
In this talk, we will introduce our recent works on correlated / entangled
photon pair sources and heralded single photon sources based on
optical fibers and silicon wire waveguides.

8554-14, Session 4

Hong-Ou-Mandel interference experimentof two independent heralded single photon
sources in an optical fiber with birefringence
Tianyi Ma, Qiang Zhou, Wei Zhang, Yidong Huang, Mingquan
Lu, Zhenming Feng, Tsinghua Univ. (China)
Single photon sources (SPSs) play important roles in quantum
communication and quantum information processing. Spontaneousfour wave mixing (SFWM) in optical fibers provides a promising way
to realize practical heralded single photon sources (HSPSs), since it iscompatible with current techniques of optical communications.
In this paper, two independent HSPSs at 1.5 um band are realized in
one polarization maintaining dispersion shifted fiber (PM-DSF) utilizing
its large birefringence. When pulsed pump light passes through an
optical fiber, two kinds of SFWM will take place simultaneously. One
is scalar processes, in which two annihilated pump photons andgenerated photon pair are all polarized along the same fiber polarization
axis. The other is vector processes, in which two annihilated pump
photons are polarized along different fiber polarization axes, either
to the two photons of the generated pair. In the PM-DSF, the large
birefringence generates obvious walk-off effect on the two pumppolarization components, which leads to an effective suppression of

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the vector processes. Hence, by proper pump polarization, correlated
photon pairs (CPPs) with different polarization directions can begenerated independently by the two scalar processes, which can beused to realize two independent HSPSs.
The indistinguishability of the heralded photons generated by the two
independent sources is demonstrated by an experiment of HongOu-Mandel (HOM) interference. Using a fiber coupler as the beam
splitter, a visibility of HOM dip of 76% is achieved with subtracting thecontribution of accidental coincidence counts, showing their potential
on quantum information.

8554-15, Session 4

Indistinguishability and semantic security forquantum encryption scheme
Xiang Chong, Li Yang, Institute of Information Engineering ofChinese Academy of Sciences (China)
The definition of security for encryption scheme is an important area of
cryptography. In this paper we investigate the indistinguishability andsemantic security into quantum context.
In our previous work, we have already defined the indistinguishability
for quantum public-key encryption scheme, and have given anecessary and sufficient condition leads to this security. Here we will
systematically define the indistinguishability and semantic security
for quantum public-key and private-key encryption schemes, and forcomputational security, physical security and information-theoretic
security.
The quantum parameters are continuous variable. In order to givethe definition of indistinguishability for quantum encryption scheme,
we first give a definition of indistinguishability for encryption schemewith continuous variable based on probability density function, anda definition of indistinguishability based on multi-outputs-circuit. We
show that these definitions are equivalent. Then we prove that theindistinguishability based on multi-outputs-circuit is equivalent toordinary indistinguishability with single-bit-output-circuit. Then we get
the definition of indistinguishability for quantum encryption scheme.
Similarly we define the semantic security.
The equivalence between computational indistinguishability andsemantic security for classical encryption scheme is already proved, but
the equivalence for information-theoretic ones is still an open problem.
For public-key encryption scheme, there is no information-theoreticallysecure classical public-key encryption scheme, so we discuss theequivalence between computational indistinguishability and semantic
security for quantum encryption scheme and between informationtheoretic ones. About private-key encryption scheme, the equivalence
between computational indistinguishability and semantic security forquantum encryption scheme and between information-theoretic ones
for classical and quantum encryption schemes all are discussed.

8554-16, Session 4

Properties of high quality heralded single
photon source based on fibers at 1.5 um
Qiang Zhou, Wei Zhang, Yidong Huang, Jiangde Peng, Tsinghua
Univ. (China)
Single photons are essential resource for quantum communicationand quantum information processing, which can carry quantum
information to distant locations. A promising scheme for single photon
generationis the heralded single photon source (HSPS), which isbased on the generation of correlated photon pairs (CPPs). Utilizing
the quantum correlation property of the CPPs, one photon of the CPP
isdetectedproviding an electrical signal to herald the other photon
as a single photon output. Recently, 1.5 um CPP generation throughspontaneously four wave-mixing (SFWM) in fiber has focused muchattention, which provides a practical way to realize 1.5 um fiber-

based HSPS. The quality of a HSPS is described by the preparation
efficiencyand g(2)(0). In the fiber-based HSPS, the preparation efficiency
is determined by the loss of the filtering and splitting system and thenoise photons generated by spontaneously Raman scattering (SpRS).
Considering the impact of the SpRS can be reduced by cooling the fiberand optimizing the frequency detuning of filtering and splitting system,
the loss of the filtering and splitting system may decide a theoretical
up-limit of the preparation efficiency.
In this paper, making use of commercial dense wavelength-divisionmultiplexing components, we optimize the frequency detuning and theloss of filtering and splitting system, improving the theoretical up-limitof the preparation efficiency. As a result, a high quality HSPS based oncooled fiberis realized with a preparation efficiency of 80%, while g(2)(0) is 0.06, showing its great potential in the application of quantum
information technology.

8554-17, Session 5

Feedforward control of high-power opticalfrequency comb (Invited Paper)
Heping Zeng, Ming Yan, Wenxue Li, East China Normal Univ.
(China)Fiber-based optical frequency comb has become an attractive nearinfrared light source for precision spectroscopy, coherent laser ranging
and optical frequency metrology due to its compactness, high precisionin time and frequency domains and long-term stability. Usually, in orderto precisely control the carrier-envelope phase or offset frequency ofhigh-power lasers, either a phase servo loop or a difference-frequencygeneration scheme has been employed. However, the two approaches
inevitably suffered from the limited feedback bandwidth and the 1/f
noise, respectively. Recently, a self-referenced feed-forward schemeby using an acousto-optic frequency shifter (AOFS) has been reported
to be an effective way of reducing phase noise of a Ti:Sapphire laser
to shot-noise-limited level. And we successfully employed the similar
scheme stabilizing the CE phase of an ytterbium-doped fiber laser
mode-locked by nonlinear-polarization rotation effect.
In this paper, we demonstrate a high-power ytterbium-doped fiber
frequency comb centered at 1030 nm by using the self-referenced feedforward scheme. As a result, the carrier-envelope phase frequency was
locked on the laser repetition rate with a relative linewidth of ~1.4 mHz.
The phase noise and timing jitter (integrated from 4 mHz to 100 kHz)
were calculated to be 370 mrad and 120 as, respectively. Meanwhile, byusing a large-mode-area (LMA) ytterbium-doped double-clad photoniccrystal fiber amplifier, the laser pulses were amplified up to 7 W withrecompressed pulse width of ~130 fs.

8554-18, Session 5

Propagation-induced transition from slow
to fast light based on coherent population
oscillation in a cascaded Erbium-doped fiber
structure
Weikun Yu, Shuguang Lu, Lingling Gu, Jin Zhou, Ming Feng,
Yigang Li, Nankai Univ. (China)
Controlling the group velocity of light based on coherent population
oscillation in optical fibers has become a popular research topic for its
many advantages and its potential applications. A change from slow
to fast propagation upon increasing the modulation frequency can berealized in a single fiber structure, however, only with narrow bandwidthand small difference between the maximum fractional advancement andthe maximum fractional delay.
In this work, we analyze the slow and fast light propagation inducedby the coherent population oscillation in a Cascaded Structure. In thefirst part, we use an erbium-doped fiber pumped at 980nm. Then weuse a wavelength division multiplexing to take out the pump beam at

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Conference 8554:
Quantum and Nonlinear Optics II
the output of this first fiber and sent the signal to the second part. The
power of the signal is controlled by a attenuator. In the second part, we
use a erbium-doped fiber without the pump beam. A change from slow
to fast propagation at the output of the second fiber can be achieved.
We also study the propagation of light in a single fiber structure in thesame conditions.
Through compared with the single fiber structure, we found thatthe change from slow to fast light is more obvious in the Cascaded
Structure. The value of delay or advancement is found to depend
significantly on the ion density and pump power in the cascaded
structure. The bandwidth is larger and the difference is bigger than thatin a single fiber.

8554-19, Session 5

Transverse localization of light in weakly
modulated photonic lattices based on twophoton photorefractive effectZhengguo Xiao, Xiudong Sun, Chunfeng Hou, Harbin Institute ofTechnology (China)
The discrete diffraction of the incident beam propagates in the weakly
modulated photonic lattices formed in two-photon photorefractive
materials is investigated. The discrete diffraction patterns in squareand hexagonal backbone structure are simulated by beam propagation
method(BPM). The effects of the external applied bias field, excitationmode, and intensity of the probe beam on the discrete diffraction
patterns are discussed in detail. It is shown, when the refractive index
modulation depth of the photonic lattices is high enough the probe
beam propagating in the photonic lattices will be localized in transverse
dimension for both on-site and off-site excitation, and the probe beam
can evolve into discrete spatial soliton under appropriate conditions.

8554-20, Session 5

Double-probe phase grating
ZhiHong Xiao, Suzhou Institute of Nano-Tech and Nano-Bionics(China)We study atomic phase grating in a four-level system driven by adegenerate probe field and a standing wave field. The simulation
results show that the diffraction efficiency of phase grating is greatly
improved due to the application of a degenerated probe beam; thefirst-order diffraction efficiency can reach up to 35%, and the high-orderdiffraction efficiency of approximate 20% is achieved.

8554-21, Session 5

Two photon absorption related femtosecond
filament in methanol solution of Tb (III)complex
MingYuan Xie, YiMin Zhu, YangYi Yang, Fuli Zhao, Sun Yat-Sen
Univ. (China); Zhizhan Xu, Shanghai Institute of Optics and Fine
Mechanics (China)
Filamentation and supercontinuum generated in the methanol solutionof a Tb(III) complex by femtosecond laser pulse from Ti: sapphiresystem has been investigated for the first time. The dynamics of thefilament formation and transmission in solution are also be discussed
quantificationally. Such an investigation of the femtosecond filament
dynamics is a good complementarity for the propagation of ultrashortlaser pulse in complex liquid media.In summary, two spectacular
nonlinear phenomena: filamentation and suppercontinuum wereobserved in our study of the methanol solution of a Tb(III) complex byusing 800nm 125-fs Ti: sapphire laser pulse with input power ranging

Return to Contentsfrom 3mW to 53mW. The lifetime of the solution is about 20ps. The
side emission light of different positions on the filament were measured
and the evolvement of filament with respect to the input power was
analyzed. The dynamic balance between the positive factor of selffocusing and the negative factors including group velocity dispersion,
plasma defocusing and two-photon absorption plays an important rolein keeping the filament in a long distance, following with a transferenhanced process between the bubbles. This investigation of the
femtosecond filament dynamics in the methanol solution of a Tb(III)complex is a good complementarity to study the propagation ofultrashort laser pulse in liquid media.

8554-28, Poster Session

The new scheme to generate Airy-Bessel
wave packets
Zhijun Ren, Zhejiang Normal Univ. (China)
Counteracting the diffraction and dispersion of wave packets inspace and time domain by making use of nonlinear effects of somemedia, three-dimensional spatiotemporal inspreading soliton waves
are generated in nonlinear media. However, the application scopes ofthree-dimensional solitons is limited because the generation of solitons
requires ultrahigh peak powers, which is devastating in some possible
applications such as being used to probe biological tissue, etc. In
addition, nonlinear solitary waves do not exist in free space. In practicalscience researches such as imaging in media, microcosm exploration
and researching its ultrafast process, it is urgently need a kind of stablelinear wave packet without spatiotemporal spread during propagation infree space.
Since Bessel and Airy function is an invariant propagation mode infree space, they can be potentially used not only in spatial but also
in temporal domains. As a result, an important scientific innovation isthat Airy-Bessel configuration wave packets with particle-like nature,
which combine spatial Bessel beams with temporal Airy pulses is first
introduced in Nat. Photonics, 4, 103 (2010). Different from nonlinear
solitary wave, Airy-Bessel configuration wave packets a kind of stablelinear wave packet without spatiotemporal spread during propagation infree space.
In the papers, by studying spatially induced group velocity dispersion(SIGVD) effect during propagation of ultrashort pulsed Bessel beams,
we find that Gaussian-Bessel wave packets can evolve as Airy-Besselin given propagation conditions. The research results are expected
to open up one new channel to generate stable linear localized wave
packets.

8554-42, Poster Session

Photo-ionization probability of 3+1
resonance enhanced multi-photon process
Guiyin Zhang, North China Electric Power Univ. (China);
Mengjun Li, Yidong Jin, North China Electric Power Univ.
(United States)
The technique of resonance enhanced multi-photon ionization (REMPI)
spectroscopy is one of the important methods for studying the
dynamics of photo-ionization. This method depends on the detectionof the ions produced in the ionization process. Thus improving thephoto-ionization probability is a crucial factor in the practical use of thistechnique.
In this work, the analytic expression of the ionization probability about
3+1 REMPI process is deduced with the theory of rate equation. The
influence of laser intensity, laser pulse duration and collision relaxation
rate on the ionization probability is analyzed theoretically. It is found thatthe ionization probability increases with laser intensity and laser pulse
duration until gets to saturation. After that, the ionization probability will
oscillate around the saturation value if laser intensity increases further.
The amplitude of oscillation increases with laser intensity at first, and58A  
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Quantum and Nonlinear Optics IIthen it will decrease even get to zero after a maximum peak comesout. We attribute the appearance of the oscillation to the phenomenaof quantum coherence caused by the energy level splitting in strong
laser field. As to the fact that the ionization probability becomes to zerowith the increase of laser intensity, it indicates that laser intensity isstrong enough so as to make the neutral particles getting to the regionof ionization suppression. It is also found that ionization probability
decreases near linearly with the increase of collision relaxation rate. But
the variation is very little due to the collision relaxation rate is far smaller
than the ionization one. So the influence of the collision relaxation rateon ionization probability could be ignored.

8554-43, Poster Session

Conversion efficiency analysis of second
harmonic generation of the novel nonlinear
crystal RbBe2BO3F2
Rui Sun, Li Wang, Chuanchen Bao, Beijing Univ. of Technology(China)For the first time, the theoretical conversion efficiency versus the
crystal lengths and polarization ratio of second harmonic generationof RbBe2BO3F2 (RBBF) crystal in type I and type II phase matchinghas been simulated by using the three wave coupled equations andenergy conservation law. RBBF crystal is pumped by the fundamental
radiation of a Q-switched Nd:YAG laser with the wavelength of 1064nm
and the shape of plane wave or Gaussian beam. RBBF is a novel
ultraviolet (UV) crystal, which is a member of KBe2BO3F2 (KBBF)
family, which has been widely used to produce harmonic generation
below 200 nm by its unique features. Compared with KBBF, RBBF
crystal has a wide crystalline phase under the existing growth system,
and in the ab direction is very easy to grow a large single crystal withtransparent area. When the pumped radiation is of plane wave, theconversion efficiency of RBBF crystal in the type I phase matchingshows a monotonically increasing trend, and eventually tends to 100%,
while the conversion efficiency of RBBF crystal in the type II phasematching varies periodically which could be as high as 78% in the type
II phase matching. When the pumped radiation is of Gaussian beam,
the conversion efficiency shows a monotonically increasing trend which
could be as high as 67% in the type I phase matching, and in the type IIphase matching the conversion efficiency varies periodically.

8554-44, Poster Session

Properties analysis of novel nonlinear
crystal: CsBe2BO3F2 by frequency doubling
Chuanchen Bao, Li Wang, Rui Sun, Beijing Univ. of Technology(China)Base on three wave coupled equations and energy conservation law,
the frequency doubing properties of CsBe2BO3F2 (CBBF) are analyzed
theorically for the first time. The phase matching angle, effective
nonlinear coefficient, walk-off angle and conversion efficiency are
simulated in type I and type II phase matching. The difference of the
CBBF optical properties between type-I and type-II are elucidated. A
wider frequency doubling wavelength range in type-I were obtained,
the lowest wavelength limit of CBBF is 201.8 nm in type-I and 268.7
nm in type-II; the effective NLO coefficient in type-I are larger; and thewalk-off angle in range of 693.9~2730 nm fundamental wavelength in
type-I are smaller. Conversion efficiency at wavelength of 1030 nm wascalculated with shape of plane wave or Gaussian wave. The conversion
efficiency in type-I increases monotonously with crystal length
increasing, while the conversion efficiency in type-II varies periodicallywith plane wave and fluctuates with Gaussian wave. Meanwhile, thecharacteristics of the frequency doubling process of CBBF has been
compared with KBe2BO3F2 (KBBF) crystal. The lowest wavelength
limit of CBBF are larger than KBBF; the effective nonlinear coefficientof CBBF are smaller than KBBF except in the range of 772.3~2500

nm fundamental wavelength in type I, this leads to a lower conversion
efficiency; nevertheless, walk-off angles of CBBF are smaller so that it
can make up for the disadvantage of effective nonlinear coefficient atsome degree. Both shape of conversion efficiencies of CBBF are little
lower than KBBF in type-I and type-II.

8554-45, Poster Session

Controlling spatiotemporal chaos ofphotorefractive ring oscillator with constantbias
XiaoXiao Chen, XiuQin Feng, ZhiHai Yao, Changchun Univ. of
Science and Technology (China)
A photorefractive crystal, which is pumped by an external laser beam, isinserted into optical ring cavity, the crystal and the ring cavity together
consisting of the photorefractive ring oscillator. photorefractive ringoscillator is a typical nonlinear optical system. With the increasing
cavity detuning and absorption loss, bifurcation and chaos phenomena
appear gradually. We study the evolutions of spatiotemporal chaos
for the system in the one- dimensional and two-dimensional map
lattices. As the system parameters are changed, we obtain different
patterns such as the frozen random state, the pattern selection state,
the defect chaotic diffusion state and fully developed turbulence statein the one- dimensional map lattice system. We can observe symmetry
breaking from four corners and the boundaries and finally lead tospatiotemporal chaos in the two-dimensional map lattices system. Then
we demonstrate that the global and local constant bias can suppress
spatiotemporal chaos in photorefractive ring oscillator by varying thebias strength. The results of numerical simulations present that theconstant bias are suitable for not only the photorefractive ring oscillator
but also the coupled photorefractive map lattice system. When constantbias is 0.045, the system is suppressed to stable periodic orbits 5,constant bias is increased to 0.05, the system is controlled into stable
periodic orbits 3, if constant bias is greater than 0.1, the system
is converted into stable periodic orbits 1. Local constant bias can
suppress spatiotemporal chaos in spatially localized regions, the rest of
the localized regions continue to spatiotemporal chaos.

8554-47, Poster Session

Chaotic characteristic in the BEC system of
a 1-D tilted optical superlattice potential withattractive interaction
Zhiying Zhang, Xiuqin Feng, Zhihai Yao, Zuolin Tian, Changchun
Univ. of Science and Technology (China)
The dynamics equation of the Bose-Einstein condensation system
can be expressed by the nonlinear Schrodinger equation (GrossPitaevskii(G-P) equation). The nonlinearity makes it possible tointroduce chaos into a quantum system. Chaos plays a role in theregularity of the system and causes instability of the condensate wave
function. In this paper, the spatiotemporal evolutions of chaos for thesystem in BEC trapped a 1-D tilted optical superlattice potential withattractive interaction is researched. The spatial evolution of chaos isshown numerically by resolving G-P equation for the system with thefourth Runge-Kutta(RK) algorithm. The chaotic characteristics in the
BEC system are well demonstrated with Lyapunov exponent, chaotic
attractor, time series and power spectrum. The results of numericalsimulations reveal that as the tilt or the amplitude of the opticalsuperlattice potential of the BEC system is increased, the chaos in
the BEC system increases. These elements make the chaotic system
more unstable and the phase-space orbit becomes more complex.
A method for controlling chaos based on parameter modulating is
proposed. Chaotic behaviors can be controlled into periodic behaviors
by parameter modulating. The results of numerical simulation show thatthe BEC system can be converted into different periodic states if wechange the modulating frequency and modulating strength. Parameter

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Conference 8554:
Quantum and Nonlinear Optics IIregion that can be used for controlling chaos is fixed by calculating the
Lyapunov exponent. The stability of periodic orbits in the modulated
BEC system is illustrated by the results of numerical calculations andphase space outline.

8554-48, Poster Session

Chaos synchronization and communicationin unidirectionally-coupled VCSELs with fiber
channel
Linfu Li, Guizhou Minzu Univ. (China); Jianjun Chen, Xinjiang
Medical Univ. (China)
As one of the microchip lasers, vertical-cavity surface-emitting lasers(VCSELs) exhibit many advantages, such as single longitudinal-mode
operation, low threshold current, circular output beam with narrow
divergence, low cost and etc. Chaos secure communication has
attracted significant attention and got an extensive application in recent
years, for its complicated nonlinear dynamics and high sensitivity tothe parameters of system. In order to realize the long-distance privacy
communications, it also raised the optical chaos communications
based on fiber. The influences of the chromatic dispersion andnonlinearity in fiber on the chaotic synchronization have been
investigated.
A novel chaotic synchronization configuration is proposed. Thissystem is constructed on the basis of unidirectionally coupled VCSELs
and signal transmission in fiber. The transmitter VCSEL is subject toan isotropic optical feedback, the receiver VCSEL is subject to an
orthogonal optical injection from the transmitter VCSEL, the chaotic
signal transmission in fiber channel is adopted, also message encoding
and decoding of the chaotic system have been investigated. The results
show that, during to the fiber nonlinear and chromatic dispersion, theamplitude characteristics of chaotic signal are distorted partially andthe system synchronization quality will be impaired, but message canbe hidden efficiently in the chaotic signal during the fiber transmission
with additive chaos modulation (ACM). Better decoding performance isachieved by choosing appropriate matched parameters.

8554-49, Poster Session

Spatial soliton tunneling in longitudinally
modulated optical lattices
Qingnan Chen, Yali Qin, Hongliang Ren, Jia Li, Zhejiang Univ. ofTechnology (China)
Nowadays, theoretical and experimental studies of solitons in opticallattice with nonlinearity have attracted a great deal of attention due
to their novel physics and potential applications in diverse branchesof science. Wealthy properties of solitons that cannot be observed inhomogeneous nonlinear media are discovered in lattice modulated
media. Variation of the lattice shape in the longitudinal direction offers
a wealth of opportunities to control the evolution of light. Due totransformation in lattice configuration along the longitudinal, a series ofnovel dynamical regimes including binary switching, soliton tunneling,
and tunneling inhibition were discussed. More recently, the tunneling
effect of self-similar optical waves has been investigated extensively.
In this paper, we study numerically the dynamics of a beam in a
focusing photorefractive nonlinear optical lattice with a longitudinalpotential barrier. Such kind of lattice with the refractive index
modulation in both transverse and longitudinal directions can berealized by induced optically in photorefractive crystals. Different soliton
states are found with different position of the input pulse, which exhibits
compression or splitting during transmission. The results also indicatethat the intensity of a beam and the transverse modulation frequencyof lattice can affect apparently the ability of tunneling. For the samelattice depth, the smaller the transverse frequency of the lattice is andthe higher peak intensity the soliton possesses, the easier the soliton
tunnels through. However, when we increase the frequency of optical
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lattice, the optical beam can successfully pass through the barrier forthe relatively small value of lattice depth as well. Otherwise, the beam
splits into some filaments when the lattice depth is large enough. In
addition, we find that beam can exhibit the behavior of oscillation
during transmission and the oscillation frequency of spatial soliton is
influenced by the baised field.

8554-50, Poster Session

Ghost interference with pseudo-thermal light
Yin P. Yao, Ren Gang Wan, Shi Wei Zhang, Tong-Yi Zhang, Xi’an
Institute of Optics and Precision Mechanics (China)
Ghost imaging (correlated imaging) has been extensively investigatedin recent years, both theoretically and experimentally. Meanwhile,ghost interference and diffraction were also studied. By using thesecond-order or high-order coherence properties of light field and thecorrelation measurement, ghost imaging was realized with quantum
entangled light, pseudo-thermal light and even true thermal light. As akind of nonlocal imaging system, the seminal light beam is split into two
separate optical paths that are spatial correlated. One beam (usuallycalled the test path) is sent to an unknown object and then detectedby a bucket detector without any spatial resolution. However, theimage of the object can be retrieved when the bucket detector signal
is correlated with the signal of a spatial resolving detector in the otheroptical path (usually called the reference path). In this paper, we firstly
prepare the pseudo-thermal source using a laser beam that passes
through a rotating ground glass plate, and obtain the parameters about
the pseudo-thermal source via Hanbury-Brown-Twiss (HBT) experiment.
Then, we perform ghost interference with the pseudo-thermal light.
The experimental results show that the quality of ghost interference isinfluenced by the rotating velocity of the ground glass plate and thelight field propagation distance. Furthermore, the distance between
the source and the object has effect on the ghost interference when
keeping the length of the test path as constant.

8554-52, Poster Session

The effect of pump focusing on theperformance of ghost imaging withentangled resource
Ming-Yang Zheng, Lian Chen, Xin-Dong Cai, Feng Li, Ge Jin,
Univ. of Science and Technology of China (China)
Ghost imaging, a novel imaging method, has been extensively
concerned around the physics community owning to its non-locality.
The image of an object can be achieved by coincidence measurement
between the bucket detection over the signal path (with object) andthe transverse scanning over the idler path (without object). In thispaper, the effect of pump focusing on the performance of ghost
imaging is studied theoretically and experimentally. As we have known,
an idealized plane-wave pump would lead to perfect transverse
momentum conservation for a perfect phase-matched crystal.
Theoretical results show that the correlation properties of the entangled
photon source are destroyed when the conversion crystal is pumped bya focused laser beam.
In our experiment, a 405 nm semiconductor cw laser is used topump a BBO (beta-barium-borate) crystal cut for type-II non-collinear
degenerate SPDC. The two rings of signal and idler light at thedegenerate wavelength 810 nm, perpendicular to the pump beam,
propagate freely with the intersection in an external angle of 3° withrespect to the pump direction. Generally, the fluorescence light in eachpath need to pass a half-wave plate and an additional BBO crystal tocompensate the transverse and longitudinal walk-off introduced by
the birefringence of the conversion crystal. However, our experimental
results indicate that the “walk off” effects almost have no effect onghost image. When the pump beam is focused by a lens, the visibility of
the image is greatly degraded. But a sharp image could be reproduced

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in the configuration first proposed by T. B. Pittman et al. for the casewith pump focusing.

8554-53, Poster Session

Two kinds of high-contrast optical filters
for the detection of Stokes and anti-Stokes
photons from cesium ensemble
Tingting Liu, Qiangbing Liang, Jun He, Tiancai Zhang, Junmin
Wang, Shanxi Univ. (China)
Laser-pumped atomic vapor cell and a properly-designed Fabry-Perot
etalon can be used as high-contrast optical filters. Especially in the caseof generation of quantum correlated Stokes and anti-Stokes photon
pairs in a Lambda-type three-level atomic ensemble with Raman
excitation, high-contrast optical filters are very important components
to pick up single-photon-level optical pulses from strong excitation
laser beams. In our experiments, we designed and characterized two
kinds of high-contrast optical filters for the detection of Stokes andanti-Stokes photons from cesium ensemble: the laser-pumped cesium
atomic vapor cell and the temperature-stabilized coated bulk etalon.
Typical peak signal transmission of ~ 75% and distinction ratio between
excitation channel and 9.19GHz-frequency-detuned signal channel of ~25 dB are measured for the laser-pumped cesium atomic filter. Typicalpeak signal transmission of ~ 84% and distinction ratio between pumpand signal channels of ~ 20 dB are measured for the temperaturestabilized bulk etalon filter. To improve the distinction ratio, normally the
mixture combination of the laser-pumped cesium atomic filter and thetemperature-stabilized bulk etalon filter will be a good choice.

8554-55, Poster Session

Study of the threshold coupling strength formutually pumped phase conjugator
Lin Ma, Jiang Zhi Guo, Liu Ji Fang, Xidian Univ. (China)
Mutually pumped phase conjugation has many attractive features suchas exchanging time-domain information, reflecting spatial informationand making incoherent-to-coherent conversion. The action mechanismof a variety of mutually pumped phase conjugator (MPPC) is almost thesame. Depending on the number of the grating (or active area) within
the crystal can be MPPC is divided into two categories: one interaction
region four-wave mixing self-oscillation mechanism and two interactive
regions four-wave mixing mechanism. The mechanism is one, two or
more four-wave mixing function area to solve difficult theory, make theresearch of the law of the threshold coupling strength for is not full, andthis problem is the key that MPPC can work normally. Its research, thatis of theoretical significance but also practical significance.
In the paper, based on the four-wave mixing mechanism and fanningeffect, the threshold coupling strength for one interaction region and
two interactive regions MPPC is researched in theory. The relation of
the the threshold coupling strength for MPPC and the fanning intensity
is studied. In the biggest fanning scattered light intensity direction theformation of MPPC requires threshold coupling strength minimum. Dueto the more efficient fanning, preset grating in MPPC has the ability to
reduce the threshold coupling strength and improve output efficiency.
These characteristics predicted by theory have been used to explain
the previous experiment phenomenon. MPPC is most likely produced
when the two incident beams is consistent. Furthermore, the thresholdcoupling strength is much lower for one-interaction-region MPPC than
two-interaction-regions MPPC. These results have importance forapplications and experimental realization of MPPC.

8554-54, Poster Session

Optimization of the experimental parametersof cesium CPT system
Zhi Liu, Jieying Wang, Wenting Diao, Jun He, Tiancai Zhang,Junmin Wang, Shanxi Univ. (China)
Coherent population trapping (CPT) is a quantum interference
phenomenon between atoms and coherent light field. The interference
process leads the atoms to be driven in a coherent superposition
dark state of the two ground states where photons are not absorbed
anymore. Based on the Lambda-type three-level atomic system
consists of cesium 6S_1/2 (Fg=3) and 6S_1/2 (Fg =4) long-lived
ground states and 6P_3/2 (Fe=4) excited state, we have experimentallymeasured and theoretically analyzed the passive coherent population
trapping (CPT) resonances in cesium vapor cells with and without
Ne as buffer gas. The impact on the CPT resonance of someexperimental parameters, such as laser intensity, relative intensity ratio
and longitudinal magnetic field, is investigated. Under the optimized
condition, the CPT resonance with full width at half maximum (FWHM)
linewidth as narrow as ~ 340 Hz is realized. The FWHM linewidth of
CPT signal linearly increases with laser intensity. By measuring thisdependence we can extrapolate the coherence relaxation time of
the two hyperfine ground states of cesium atoms (the lifetime of thecoherent superposition dark state) at zero laser intensity. For the case ofcesium cell filled 2 Torr Ne as buffer gas, the coherence relaxation timeis ~ 1.06ms. For the case of pure cesium cell without buffer gas, it is ~17µs. When increasing the longitudinal magnetic field, CPT resonances
are split into 7 resolved components in the sigma^+_sigma^+ (orsigma^-_sigma^-) laser polarization configuration.
These results, as well as those relevant published works, will provide
more references for development of high-performance CPT atomic
clocks as well as high-sensitive CPT atomic magnetometer. In the next
step, we will further reduce the relative phase noise of phase-locked
dichromatic lasers and optimize the pressure ratio of Ne buffer gas in
the cesium cell and temperature of cesium cells. Expect to get narrower
CPT linewidth and better signal-to-noise ratio.

8554-56, Poster Session

Multistability of nanomechanical mirror in
atom-assisted optomechanical cavity
Changbao Fu, Jilin Univ. (China)
We study the multistability of nanomechanical mirror by theoretical
calculations and numerical simulations in atom–assisted
optomechanical cavity. We obtain that the multistability ofnanomechanical mirror changes along with original detuning between
the transition frequency of atom and the frequency of cavity field
for several elastic coefficients of spring. In addition, we find that themultistability of nanomechanical mirror will be increased by two when
the level of atom is increased by one.

8554-57, Poster Session

All-optical switching characteristics analysis
in an optimized nonlinear Bragg grating witha [pi] phase shift
Jianjun Chen, Xinjiang Medical Univ. (China); Linfu Li, Guizhou
Univ. (China); Murat Hamit, Yanting Hu, Xinjiang Medical Univ.
(China); Xiaoxi Fan, Abuduaini Kuduluke, College of Medical
Engineer Technology of Xinjiang Medical University (China)
We numerically study the nonlinear switching characteristics of
optical pulses transmitted though optimized fiber Bragg grating witha phase shift. The nonlinear coupled-mode equations were solved
numerically based on the time-dependent transfer-matrix method. We
show that the phase shift grating is superior to the uniform grating in
the enhancement. The nonlinear Bragg grating is 3mm long and has
a strength of , corresponding to the enhancement to be a factor of
15. It shows that the use of phase shift gratings reduces effectively

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Conference 8554:
Quantum and Nonlinear Optics II
the switching threshold, but the on-off contrast is generally declined
which can be generally improved through the introduction of tapered
parameters. In addition, the narrowed transmitted pulse for positivetapered nonlinear Bragg grating is a Bragg soliton owing to the balanceof anomalous group velocity dispersion and self-phase modulation(SPM). From the comparison of the introduction of tapered and chirpparameters, it can be found that the tapered nonlinear Bragg gratingwith a phase shift is more preferable for achieving the larger on-off
contrast.

8554-58, Poster Session

High repetition rate tunable mid-infrared
optical parametric oscillator based on
MgO:PPLN
Yongji Yu, Xinyu Chen, Chao Wang, Chunting Wu, Guangyong
Jin, Changchun Univ. of Science and Technology (China)High repetition rate nanosecond mid-infrared (3~5 ?m) lasers haveattracted the interest of scientists in many applications such as militarycountermeasures, remote monitoring of the special environment, andso on. Quasi-phase matched optical parametric oscillator (OPO) basedon periodically-poled crystal can offer a high conversion efficiency
and wide wavelength tunability, especially periodically-poled MgO
doped lithium niobate (MgO:PPLN) which has a low coercive field andbig effective nonlinear coefficient. However, the damage threshold of
MgO:PPLN is as low as 10 J/cm2 (1064 nm, 10 ns pulse), so raising therepetition rate of the pulse is an effective way to improve the power ofthe lights generated by OPO. In this paper, we present a mid-infrared
OPO with the idler wavelength of 3.86 µm at the repetition rate of
200 kHz, and a high repetition rate electro-optic (EO) Q-switched
Nd:GdVO4 laser with a double-crystal RbTiOPO4 (RTP) EO modulator
is used as the pump source. The OPO is designed as an extra-cavity
singly resonant optical parametric oscillator. The threshold value of the
OPO system is only 1.3 W at 1.06 µm. When the MgO:PPLN crystal
is operated at 90 °C and the pump power is 10.5 W with a repetitionof 200 kHz, the maximum average output power of 1.82 W at idler
wavelength 3.85 µm and pulse width of 14.3 ns are obtained. The
slope efficiency of the 3.85 µm laser with respect to the pump laser is
21.3%. The M2 factors of the 3.85 ?m laser are 1.84 and 1.76 in theparallel and perpendicular directions, respectively. The mid-infrared
tunability of 3.7~3.9 µm can be achieved by adjusting the temperatureof MgO:PPLN crystal from 210 °C to 35 °C.

8554-60, Poster Session

Cerenkov radiations in nonlinear photonic
crystal and waveguide
Changdong Chen, Xiaopeng Hu, Jiong Zhou, Nanjing Univ.
(China)By analogy with the Cerenkov radiation from particles, nonlinear
Cerenkov radiation (NCR) results from nonlinear polarization driven
by light field. The generation as well as modulation of NCR has drawn
increasing research interests in recent years. Our research works mainly
focus on the experimental realizations of NCR in nonlinear photonic
crystals, including frequency up-conversions and down-conversions.
The phase velocity of the nonlinear polarization waves can be
accelerated with a backward reciprocal vector while decreased with aforward one provided by the structure, thus the characteristics of NCR
were modulated. By this means, cascaded Cerenkov third harmonic
generation and Cerenkov difference frequency generation were realized.
In addition, some novel phenomena, such as mode-coupling Cerenkov
sum frequency generation and elastic scattering were observed.

8554-61, Poster Session

The three-photon resonant nondegenerate
six-wave mixing via quantum interference
Juan Sun, Jiang Sun, Ying Wang, Hongxin Su, Jinfeng Cao,
Hebei Univ. (China)
We study the quantum interference in three-photon resonant
nondegenerate six-wave mixing (NSWM) in a five-level system inwhich the middle level of six-wave mixing and other level are coupled
by a strong laser field. The coupling field-dependence of the NSWM
signal intensity, and the spectrum of the NSWM with a coupling field,
are discussed. We find that in the presence of a strong coupling field,
the three-photon resonant NSWM spectrum exhibits Autler-Townes
splitting, which reflects the levels of the dressed states. It also leads toeither suppression or enhancement of the NSWM signal. Thanks to theenhancement of NSWM signal caused by quantum interference, thedressed state, created by a coupling field, can replace the atom intrinsic
level and serve as the middle level of three-photon resonance. Thus the
middle level of three-photon resonance can be controlled by a coupling
field.

8554-59, Poster Session

8554-62, Poster Session

Electromagnetically induced absorption inlambda-type three-level system driven bybichromatic coupling field

Probe correlation and energy gap of Blochbands in one dimensional optical lattice bymatter wave amplification

Zhanfei Yan, Lijun Yang, Lijin Ma, Xiaomin Feng, Shuqing Guo,
Hebei Univ. (China)

Xuguang Yue, Xiaoji Zhou, Xuzong Chen, Peking Univ. (China)

The probe absorption speciality of the -type three-level system driven
by bichromatic coupling field and weak probe field is investigated.
We obtain the probe absorption spectrum for different frequencies ofcoupling field by solving the density matrix equation and numericalanalysis. For same intensity but different frequency detuning of thecoupling field, three electromagnetically induced absorption (EIA) in theabsorption profile of probe field are simultaneously observed. We report
the dependence of EIA on the frequency of the bichromatic coupling
fields. The results show that central EIA always appears at the resonant
frequency of probe field, with the constant intensity. The location of
the secondary EIA vary with the frequency detuning of coupled field,
and the intensity of the absorption peaks decrease with the increasing
detuning. Finally, we present an analysis based on dressed states to
explain our numerical results.

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Using resonant Superradiant Rayleigh Scattering (SRS) , correlations ofa Bose gas released from an optical lattice are measured. Conditions
are chosen so that, after initial incident light pumping at the Bragg angle
for diffraction, superradiant scattering into theBragg diffracted mode is
preponderant due to matter-wave amplification and mode competition.
A temporal analysis of the superradiant scattering gain reveals
periodical oscillations and damping due to the initial lack of coherence
between lattice sites. Such damping is used for characterizing
first-order spatial correlations with a precision of one lattice period.
Furthermore, We use a coherent Bragg diffraction method to impart
an external momentum to ultracold bosonic atoms trapped in a onedimensional optical lattice. This method is based on the applicationof a single light pulse, with conditions where scattering of photons
can be resonantly amplified by atomic density grating. An oscillatory
behavior of the momentum distribution resulting from the time evolution
in the lattice potential is then observed. By measuring the oscillating
frequencies, we extract multiband energy structures of single-particle

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excitations with zero pseudomomentum transfer for a wide range oflattice depths. The excitation energy structures reveal the interaction
effect through the whole range of lattice depths

8554-63, Poster Session

Manipulating the momentum state of BoseEinstein condensate by standing wave
pulsesYueyang Zhai, Xiaoji Zhou, Xuzong Chen, Peking Univ. (China)
We analyze the effects of sequences of standing-wave pulses on a
Bose-Einstein condensate. We present a scheme for nonadiabaticallyloading a Bose-Einstein condensate into the ground state of a onedimensional optical lattice within a few tens of microseconds, i.e.,
typically in less than half the Talbot period. We apply amethod forflexible manipulation of the atomic momentum states where thestanding-wave pulses are less limited in pulse intensities and durations.
The experimentalobservations are in good agreement with a numericalsimulation based on band structure theory in an optical lattice.

8554-64, Poster Session

Transient behaviour of EIT and EIA in
an optical-radio two-photon coupling
configuration
Xiaoli Li, Zicai Yang, Hebei Univ. (China)
Electromagnetically induced absorption (EIA) and transparency (EIT)
are quantum intervene phenomena due to the interaction of coherent
electromagnetic fields and multiple level atom system. They havereceived sufficient attention for their potential applications in quantum
communication storage and quantum calculation. In this paper, a fourlevel optical-radio two-photon coupling system is firstly established,
and a set of density matrix equation of motion is derived using therotating wave approximation method. Both EIA and EIT can be obtainedin this four-level system consisting of an optical-radio two-photon
coupling field and a probing field. The formation of EIA and EIT canbe showed in terms of a transient state picture in this paper. It can beseen that the optical coupling field in this system has a crucial effecton the forming of EIA and EIT. An EIA is observed under a resonant
optical coupling and it evolves into an EIT when there is a detuning. In
this paper, the formation of EIA and EIT are studied separately. Whenboth optical coupling field and radio coupling field are resonant, theformation of EIA can be shown from absorption minimum to absorption
maximum as time increases. On the other hand, when optical coupling
field is off-resonant and radio coupling field is resonant, the formationof EIT can be shown from absorption maximum to absorption minimumas time increases. At the same time, the dependence of the frequency
position of EIA and EIT on Rabi frequencies and frequency detunings oftwo coupling fields is investigated.

8554-65, Poster Session

Resonant optical nonlinearity of Nbdoped silica fiber measured with LPFG
interferometer
Litao Wang, Shanghai Unv. (China); Na Chen, Zhenyi Chen,
Tingyun Wang, Shanghai Univ. (China)
Recently, specialty fibers with various functional material doping
have attracted significant attention due to their unique performance.
Nonlinear optical properties, both the resonant nonlinearity and theRaman spectra of specialty fibers have been studied for a numberof compositions. In this paper a new kind of Nb-doped silica fiber

is fabricated combining MCVD and atomic layer deposition (ALD)
technologies. We measured its optical absorption spectra in the range
from 400 nm to 1650 nm with the cut-back method. The Nb-doped
fiber shows broadband absorption in the vicinity of 900nm. Then,
we measured the Raman spectra of Nb-doped silica fiber under theexcitation of 785nm laser. The Raman scattering intensity is enhanced
compared with the conventional single-mode fiber. Then, we used
Mach-Zehnder Interferometer (MZI) formed by two long-period fiber
gratings (LPFG) to measure the resonant nonlinear refractive index
of the specialty fibers. Two LPFGs were fabricated by the method of
CO2 laser pulse writing technology. Then, a section of 15cm-lengthNb-doped silica fiber was inserted between the LPFG pairs. The fringe
visibility of formed MZI reached 9dB. The interference fringe shifts
when we launched the 532nm pumping laser into the interferometer.
As the launched pumping power increased, the interference fringes
shifted toward the longer wavelength. The total fringe shift of the Nbdoped fiber was 0.1 nm with the 532 nm laser at the launched power of
25mW. The resonant nonlinear refractive index of the Nb-doped fiber isestimated to 8.12?10-16m2/W around 1537nm.

8554-22, Session 6

Relative delay enhancement of light pulse
propagating in nonlinear medium via cavity
resonance effect (Invited Paper)
Fang Bo, Jie Wang, Guoquan Zhang, Jingjun Xu, Nankai Univ.
(China)Based on the transverse-phase modulation effect, the analyticalexpression of the relative delay of a sinusoidally modulated
fundamental-mode Gaussian beam passed through a nonlinear medium
filled in a thin resonant Fabry-Perot cavity were derived. As examples,the dependences of the relative delay of the signal pulse transmitted
from ruby, alexandrite and GbAlO3 crystals on the experimental
parameters were discussed. The results showed that the relative delayof the signal pulses can be significantly improved by several orders ofmagnitude through the introduction of a resonant Fabry-Perot cavity inthe case of weak absorption of nonlinear media. The same maximum
relative delay was achieved in the same nonlinear medium for different
lengths in the case of impedance matching, which means that microcavities made by nonlinear medium have the ability to produce thesame amount of relative delay as their macro- counterparts.

8554-23, Session 6

Optical frequency comb generation throughquasi-phase matched quadratic frequency
conversion in a micro-ring resonator
Zijian Wu, Nanjing Univ. (China); Yang Ming, Nanjing University(China) and Nanjing Univ. (China); Fei Xu, Yan-qing Lu, Nanjing
Univ. (China) and Nanjing University (China)
We propose optical frequency comb generation in a monolithic microring resonator. Being different from the previously reported nonlinear
optical frequency combs, our scheme is based on more efficient
quadratic frequency conversion rather than the third-order nonlinearity.
To overcome the phase mismatch, a partly poled nonlinear ring is
employed. Cascading second harmonic generation and parametricdown conversion processes thus are realized through quasi-phasematching (QPM). In our theoretic model, a half poled Lithium Niobate‘add-drop’ ring system is considered. Based on coupling equations,the second-harmonic generation efficiencies are calculated. And two
influencing factor, pump power and coupling coefficient between
waveguide and ring, are analyzed. Through these analyses, proper
coefficients are chosen and the optical frequency comb generation
efficiency are calculated. The interactions among 22 different
whispering-gallery modes are included. A 56% internal generation
efficiency is got from these calculations.

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Conference 8554:
Quantum and Nonlinear Optics II

8554-24, Session 6

Soliton spectral tunneling effect in multicladding single mode fibers with three zerodispersion wavelengths
Jungao Hu, Xianglong Zeng, Shaofei Wang, Qianwu Zhang,
Tingyun Wang, Shanghai Univ. (China)
When the waveguide dispersion is engineered to make a normal groupvelocity dispersion (GVD) region located between the two anomalous
GVD regions, a sharp switching of the soliton self-frequency shift due
to phase-matched dispersion wave occurs from one anomalous GVD
region to another, known as soliton spectral tunneling (SST) effect.
SST effect is a promising approach to achieve nonlinear wavelength
conversion and octave-spanning supercontiuum.
In this paper, we investigate the generation of SST effect in multicladding single mode fibers. We design the multi-cladding fibersthat can exhibit three zero-dispersion wavelengths. Phase matching
between soliton and dispersive waves can be satisfied by engineering
the waveguide dispersion curve. Fiber geometries with appropriate
refractive index difference and fiber radius are selected to generate
this unique dispersion property and the mechanism of multi-cladding
fiber exhibiting multi zero-dispersion wavelengths is discussed. The
standard split-step Fourier method is implemented to solve the GNLSE
numerically.
Simulation results show that the SST effect is clearly observed, while
the resonant frequency falls in the anomalous GVD region. The center
frequency of output pulse in SST effect is investigated numerically andanalytically. The detail studies present the phase-matching condition
with the dispersive pulses in different engineered dispersion curvesof multi-cladding fibers. The simulation results reveal the relationshipbetween the carrier frequency of input pulse and center frequencyof the dispersion waves. The predicted results by phase-matchingcondition are in agreement with extensive numerical simulations. The
soliton number N is significant to SST effect, which has a great on thevariation of the threshold length.

8554-25, Session 6

The chaotic dynamics of ultra-long erbiumdoped fiber ring laser
Juan Zhang, Lingzhen Yang, Naijun Xu, Xiangyuan Zhang,
Taiyuan Univ. of Technology (China)
We report an experimental study of chaotic generation in an ultra-longerbium-doped fiber ring laser (ULEDFRL). The 980 nm semiconductor
laser (LD) is used to pump an erbium doped fiber (EDF) with 8m longby a 980/1550 nm wavelength division multiplexed coupler (WDM). The
polarization isolator (ISO) forces the light to operate in unidirectional.
The polarization controller (PC) is used to adjust the polarization stateof the light. The total cavity is 752 m. The output coupler with a ratioof 90:10 has 10% of the lasing light for output detection. During theexperiment, we adjust the PC under a fixed pump power to make theoutput power at the maximum value. When the drive current is adjusted
from 180 mA to 413 mA, The ULEDFRL shows chaotic oscillation. The
experimental results reveal the chaotic laser of the ULEDFRL shows
narrow width in the autocorrelation curve, and the full width at half
maximum (FWHM) of the autocorrelation curve is 0.125ns. The chaotic
laser can be used in the range finder with centimeter-range resolution.

8554-26, Session 7

Study on parametric amplification effect infiber
Xiuping Sun, Changchun Univ. of Science and Technology(China)Return to Contents

The basic principle of Analysis parametric amplification in fiber
was discussed in the paper, as well as basic factors of influence toparametric amplification. Taking the fiber as the carrier and the gain
medium, we respectively selected wavelength of 1445nm; 1455nm;
1535nm, as the pumping light, the amplification of 1555nm signal light
can be accomplished. Experimental results show that, at a certain
wavelength range, fiber optical amplification can be achieved throughparametric process.

8554-27, Session 7

SPM and XPM effects on properties ofchaos optical fiber fence system based on
semiconductor fiber ring laser
Chen Liu, Nian Fang, Lutang Wang, Zhaoming Huang, Shanghai
Univ. (China)
The dependence on the initial conditions is one of the key
characteristics of chaotic systems. Base on this, a chaos optical fiber
fence system has been put forward by employing a semiconductor
fiber ring laser (SFRL) as the sensing medium. The output waveformof the SFRL has a framing structure. The traveling time of light in thering over one cycle is a ring period or a frame. The adjacent-frame
waveforms are similar. However the similarity is declined when an
external disturbance acts on the sensing fiber. Furthermore the declined
degrees are proportional to the locations where disturbances happenedin the fiber ring. Therefore the disturbance can be detected and locatedby the change in the adjacent-frame similarity. This paper presents an
improved dynamic model of the chaos optical fiber fence system firstly
involved in the SPM and XPM effects of the fiber. A matrix related to thefiber polarization states is introduced to the sensor model that is madeup of nonlinear phase shifts of two orthogonal polarization componentsof the electrical fields of the light in the ring induced by the SPM and
XPM effects. We investigate numerically the influence of the nonlinear
effects on the sensing properties of the long-range fence systemespecially in the adjacent-frame similarity. We calculate self-correlationof chaos waveforms to get normalized self-correlation coefficients for
judging the change of the adjacent-frame similarity. The simulation
results are compared with the ones based on the original model in
different ring lengths, which reveals the relation of the adjacent-frame
similarity and the SPM/XPM effects.

8554-29, Session 7

The self-bending and interactions of (1+1)
dimension spatial solitons in photorefractive
crystalYali Qin, Jia Li, Hongliang Ren, Hao Wen, Zhejiang Univ. ofTechnology (China)
Spatial solitons, beams that do not spread owing to diffeaction when
they propagate, have been demonstrated to exist by virtue of a variety
of nonlinear self-trapping mechanisms. Photorefractive spatial solitons
can be formed when the diffraction of the beam is exactly balanced
by self-focusing due to the photorefractive material nonlinearity at
mW power levels. There will be the potential application in all opticalcommunications.
By considering the diffusion effect, we investigate the features of theself-deflection of the screening-photorefractive spatial soliton andthe influence of first-order and higher-order space charge field on the
propagation characteristics both on the theory and numerical simulation
aspects. The results show that the center of the optical beam moves
on a parabolic trajectory; As to the highter-order space charge field,
the self-bending process is further enhanced by a factor that varies
cubically with the applied field. The numerical study shows that thebending distance of the soliton beam center increase, reaching its
maximum value at the characteristic temperature by taking into accont

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the temperature dependence of the diffusion effect and the dark
irradiance. Numerical investigations of the screening-photorefractive
spatial solitons interaction. The influnces of initial phase differnce, theintensity and peak separation on the interactions between screening
bright solitons are investigated, the results show that the in-phaseinteraction will result in the separation of two solitons from each other;
As for the anti-phase interaction side, two solitons separated each otherand delect simultaneously to the same side. Finally, interactions among
multiple solitons are also investigated.

8554-30, Session 8

Ultrafast molecular symmetry breaking
dynamics probed by coherent twodimensional infrared spectroscopy (Invited
Paper)
Jianping Wang, Institute of Chemistry (China)
Ultrafast two-dimensional infrared (2D IR) spectroscopy can probe
fast structural dynamics of molecules in condensed phases underthermal equilibrium conditions. In these systems, a solute molecule
constantly changes its shape and symmetry as a result of solventsolute interactions. Such a dynamical process cannot be easily probed
by conventional spectroscopic method. In this work, using a highly
symmetric anion, hexacyanocobaltate (Co(CN)6 3-), we examined the
dynamical symmetry breaking and regaining processes using the 2D IR
method. Using the CN stretching mode as the intrinsic structural probe,
the symmetry breaking and regaining processes of Co(CN)6 3- were
found to closely associated with the localization and delocalizationof the vibrational excitations of the CN stretches. In water, glycol andglycerol, such events occurred on the time scales of a few to tens ofpicoseconds.

8554-31, Session 8

Linear and nonlinear optical properties ofliquid solutions of Rhodamine B dye and Au
nanoparticles
Fereshteh Hajiesmaeilbaigi, Yasaman Golian, Asma Motamedi,
Univ. of Tehran (Iran, Islamic Republic of); Eftekhar Bostandoust
Nik, Sharif Univ. of Technology (Iran, Islamic Republic of)
There is considerable interest in understanding optical nonlinearities
of dyes for widespread application. The fluorescent yield and lasing
efficiency of these organic dyes have been studied extensively.
Metallic nanoparticles can strongly influence the optical responseof organic and inorganic materials. It has been demonstrated thatmetals affect the shapes of absorption and emission spectra as wellas the kinetics of luminescence decay. Metallic nanoparticles alsostrongly affect nonlinear response of optical materials. If a mixture ofdye solution and metallic nanoparticles is used as a laser medium,the SP-induced enhancement of absorption and emission of dye cansignificantly improve the laser performance. In this study Au nanocolloid
is performed by laser ablation method. Absorption and emission
studies were carried out for the laser dye Rhodamine B dissolved indoubled distilled and DI water with and without the presence of gold
nanoparticles. Results show the red shift of the fluorescence emission
in the case of dye with the presence of gold nanoprticles. Here we
report our results on the measurement of nonlinear absorption in
Au, Au/Rhodamine B and Rhodamine B using the standard Z-scan
technique. The excitation source was 150 mW CW laser at 532 nm.
The input beam was focused with 19.5 cm lens and the sample wasscanned across the focus using a micrometer translation stage. The
beam waist at focus was estimated to be 48 ?m and the corresponding
peak intensity was estimated to be 3.98?103 W/cm2. We observed thereversed saturable absorption behavior for this peak intensity.

8554-32, Session 8

A nearly-zero ultra-flattened dispersion
polarization-maintaining photonic crystal
fiber for nonlinear applications
Yani Zhang, Univ. of Glamorgan (United Kingdom); Dun Qiao,
Northwest Univ. (China)
The dispersion management and tailoring in highly nonlinear PCFs
can be achieved by utilizing the design flexibility in the fiber geometry
including the core region and the microstructured cladding, fiber
compound material, etc. Specifically, GVD with reduced wavelength
dependence, i.e. a flattened dispersion profile is suitable for SC
generation in telecommunication window. The preserved polarization
state along the fiber is a desired feature for SC generation, as
less power is required due to enhanced nonlinear interaction. The
polarization maintainability is also important for stable SC generation
therefore a fiber design with good polarization-maintaining (PM)characteristics is desired. Specifically, pumping the PM nonlinear
fiber with the pumper laser polarization aligned to one of the principle
axis, could achieve better power compared to non-PM nonlinear fiber.
Moreover, the output is also kept polarized in the PM fiber leading toincreased usability of the generated light. To achieve the near-zeroultra-flattened chromatic dispersion in PCFs, several designs have been
proposed but lack of the stable polarization-maintaining properties,
or involving many design parameters such as different air hole size inthe cladding structure, and/or modifications in the core region. The
fabrication for low dispersion fibers requires precise control of thegeometrical parameters such as air hole shape, core diameter, lattice
pitch, etc. For this reason, the research for novel and relatively simple
designs of HNL-PCF with polarization-maintaining properties for stablenonlinear applications is necessary. In this work, we employ the indexguiding PCF structure with uniform air-silica lattice, and the defectedcore to achieve flattened dispersion profile. Based on the relatively
simple structure, we optimize the design parameters to achieve otherdesirable properties including high nonlinearity and high birefringence.
The optimized structure is numerically analyzed by using the fullvector finite difference method (FDM). The boundary conditions aretreated with anisotropic perfectly matched layer (APML) to minimize thereflections at the boundary and thus simulate an unbounded region.

8554-33, Session 8

Efficient generation of mid-infrared
photons at 3.16 um by coherent frequency
downconversion
E. Wu, Kun Huang, Qian Zhou, Xiaorong Gu, Haifeng Pan,
Heping Zeng, East China Normal Univ. (China)
We demonstrated an efficient way for generating a mid-infrared source
at 3.16 ?m by coherent coincidence downconversion. The signal lightat 1.04 ?m was frequency downconverted by the synchronized pumppulses at 1.55 ?m with an conversion efficiency of 65%.
The experimental scheme mainly consisted of three parts: laser
synchronization, frequency downconversion and photon detection. The
pump and signal sources were taken from two fiber lasers arranged in
the master-slave cavity configuration. In order to emulate the quantum
light source, the signal source was attenuated to the single-photon
level. The synchronized signal photons and pump pulses of the samepolarization were combined and sent into an 50-mm-long MgO:PPLN
crystal to facilitate the type I quasi-phase matching. The temperature of
the crystal was optimized at 23.5 °C for the grating period of 30.49 ?m.
The peak conversion efficiency of 65% was achieved at 80 mW. The
downconverted mid-infrared light was directed into a monochrometerfor spectrum measurement. The spectrum was centered at 3.16 ?mwith a bandwidth of 3.7 nm. Without the incident signal at 1.04 ?m,the noise spectrum showed no observable peaks around the target
wavelength of the DFG photons.

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Conference 8554:
Quantum and Nonlinear Optics II
The mid-infrared source could be applied to sensitive high-resolution
spectroscopy of the fundamental absorption band of methane.
Moreover, the output mid-infrared light could be spectrally andtemporally controlled by engineering the pulse property. Thanks tothe preservation of the quantum feature in the coherent frequency
downconversion, if nonclassical signal source was implemented,
nonclassical mid-infrared light could be generated.

8554-34, Session 8

Large nonlinearity enhancement of Ag/MEHPPV nanocomposite by surface plasmon
resonance at 1550 nm
Cuicui Lu, Xiaoyong Hu, Qihuang Gong, Peking Univ. (China)
Recently, the construction of photonic materials having large nonlinear
susceptibility and ultrafast response at 1,550 nm has attracted muchattention because of their important applications in the fields of
optical computing, optical signal processing, optical interconnection
systems , and integrated photonic devices. The third-order nonlinear
susceptibilities of traditional semiconductor materials such as Si and
GaAs are relatively small. Various approaches, including synthesizing
materials with inherently large nonlinear responses at the opticalcommunication range, constructing composite materials basedon local-field-enhanced nonlinearity, and forming photonic microresonators to enhance the interactions of light and matter, have been
proposed for developing such materials. However, the chemical
syntheses are very complicated, and it is also very difficult to fabricate
high-Q photonic micro-resonators. An alternative method is to constructnanocomposite materials consisting of noble metal nano-particles
dispersed in a dielectric matrix. Noble metal nanoparticles possess
excellent optical nonlinearity because of their strong quantum size
effect. An ultra fast response time can be achieved using fast relaxationof nonequilibrium electrons. We experimentally demonstrate a large
third-order nonlinear susceptibility for a nanocomposite made of poly[2methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] doped with silver
nanoprisms at 1,550 nm, achieved based on nonlinearity enhancement
associated with strong surface plasmon resonance. The nonlinear
refractive index reaches –1.37 x 10–12 m2/W, which is three orders ofmagnitude larger than that of pure poly[2-methoxy-5-(2-ethylhexyloxy)1,4-phenylenevinylene]. An ultrafast response time of 18.7 ps is reachedusing fast energy transfer from excited states of organic molecules tosilver nanoprisms. A low-power and ultrafast nanocomposite photonic
crystal all-optical switching is also realized.

8554-35, Session 9

Control of electron localization in the
dissociation of H$_2^+$ using orthogonallypolarized two-color sequential laser pulses(Invited Paper)
Feng He, Shanghai Jiao Tong Univ. (China)
Orthogonally polarized two-color sequential laser pulses are used tocontrol the electron localization in the dissociation of H$_2^+$. The
first single attosecond pulse, whose polarization axis is perpendicular
to the molecular axis, excites H$_2^+$ from 1s$sigma_g$ to 2p$pi_u$,
and the time-delayed infrared pulse, whose polarization axis is parallelto the molecular axis, steers the electron between two nuclei. The
simulation of the time-dependent Schr”odinger equation predicts thecontrol degree of the electron localization can be up to 90% with thecurrent laser technology. To the best of our knowledge, we first revealthat the new mechanism for the asymmetric localization is the mixtureof 2p$pi_g$ and 2p$pi_u$ orbits.

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8554-36, Session 9

Linear and nonlinear localized modes in
the width-disordered one-dimensional
waveguide arrays
Lei Xu, Yi Yin, Fang Bo, Jingjun Xu, Guoquan Zhang, Nankai
Univ. (China)
Transverse localization of light in one-dimensional waveguide arrayswith width disorder has been studied in both linear and nonlinear
regimes. In the linear regime, with the increase in the width disorderlevel, more and more eigen modes become localized near the bandedges. The corresponding eigenvalues penetrate into the semi-infinite
bandgap and the first bandgap of the uniform periodical waveguidearray, which makes the bands extend and the bandgaps narrow withincreasing width disorder level. When one introduces a refractive index
defect, i.e., the refractive index of a specific waveguide is higher orless than the surrounding ones, into the disordered waveguide array,
localized defect modes will be generated in the semi-infinite bandgap
or in the first band gap. These defect modes will be delocalized with
the increase of the width disorder due to the interaction with the nearby
eigen modes.
In the nonlinear regime, a self-focusing nonlinearity tends to enhance
the transverse localization of the nonlinear disordered modes originatingfrom Anderson modes near the edge of the semi-infinite bandgap.
While the inverse participation ratio first increases to a maximum in thefirst bandgap and then decreases and enters the second band for the
nonlinear disordered modes originating from Anderson modes near theedge of the first bandgap with increasing self-defocusing nonlinearity.
This intriguing light localization behavior may be attributed to theinterplay between the nonlinear disordered modes and the eigen modesof the width-disordered waveguide array.

8554-37, Session 9

Evanescent coupling assisted four-wave
mixing in a silicon-on-insulator directional
coupler
Wei Ding, Institute of Physics (China); Owain Staines, GarethHobbs, Andrey Gorbach, Charles de Nobriga, William J.
Wadsworth, Jonathan C. Knight, Dmitry V. Skryabin, Univ. ofBath (United Kingdom); Michael J. Strain, Marc Sorel, Richard
M. De La Rue, Univ. of Glasgow (United Kingdom)
Four-wave mixing (FWM) has been extensively explored in optical fibers
and more recently in on-chip silicon-on-insulator (SOI) waveguides.
A phase-matched FWM with a pair of degenerate pump photons
generating and amplifying signal and idler photons is referred as
modulational instability (MI). Following theory of FWM in waveguidearrays, we utilize evanescent couplings between neighboring
waveguides to control the phase-matching condition in FWM. In
experiments, a set of single SOI waveguides with the waveguide width
decreasing from 380nm to 340nm demonstrate that changing the
waveguide group velocity dispersion (GVD) at the pump wavelengthof 1532nm from being anomalous to normal makes MI gain graduallydisappear. Then, we perform the same experiment with an arrayof two 380nm-wide SOI waveguide, and demonstrate that for thelarge separation of 900nm and 800nm, MI gain is present as for the
single waveguide; while for the small separation of ~400nm, the gain
disappears. This transformation of phase-matching in FWM is attributed
to the fact that the coupling induced dispersion changes the net GVDof the symmetric supermode from being anomalous for large separation
to being normal for small separation. Our observation illustrates that the
coupling-induced GVD can compete and exceed in value the GVD of asingle SOI waveguide. This creates a new previously unexplored degreeof freedom to control FWM and other dispersion dependent processeson chips.

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Quantum and Nonlinear Optics II

8554-38, Session 98554-40, Session 9

Role reversal in a Bose-condensed
optomechanical system

All-optical format conversion from 16QAM
to QPSK based on four-wave mixing insemiconductor optical amplifier

Keye Zhang, East China Normal Univ. (China); Pierre Meystre,
College of Optical Sciences, The Univ. of Arizona (UnitedStates); Weiping Zhang, East China Normal Univ. (China)
We analyze the optomechanics-like properties of a Bose-Einsteincondensate (BEC) trapped inside an optical resonator and driven byboth a classical and a quantized light field. We find that this system
exhibits a nature of role reversal between the matter-wave field and thequantized light field [1]. As a result, the matter wave field now plays therole of the quantized light field, and the quantized light field behaves
like a movable mirror, in contrast to the familiar situation in BEC-based
cavity optomechanics [2]. We demonstrate that this system can lead tothe creation of a variety of nonclassical matter-wave fields, in particular
Schrödinger-cat states [3], and discuss several possible protocols tomeasure their Wigner function [4].
[1] Our work has been published in Phys. Rev. Lett . 108, 240405 (2012)as an editor suggestion.
[2] Brennecke et al., Science 322, 235 (2008); K. W. Murch et al., Nat.
Phys. 4, 561 (2008).
[3] S. Mancini et al, Phys.Rev.A 55, 3042 (1997); S. Bose et al, ibid. 56,
4175 (1997).

Yueying Zhan, Min Zhang, Mingtao Liu, Xue Chen, Beijing Univ.
of Posts and Telecommunications (China)
A scheme of format conversion from optical 16QAM to QPSK
signal based on cascaded-FWM in SOAs is proposed. Theoreticalanalysis and simulations of the scheme are conducted to validate thefeasibility of the proposal. Theoretical analysis and simulations of theformat conversion scheme are conducted to validate the feasibilityof the proposal. In this paper, we present an investigation of format
conversion from 16QAM signal to QPSK signal through both theoreticalanalysis and simulation approaches. A phase conjugated of 16QAM
signal is generated after the first FWM process in an SOA. And thenthe QPSK signal is converted after non-degenerate four wave mixing(ND-FWM) process in another SOA. The performance and the optimum
bias current of the SOAs, the pump frequency space &#61508;fand the performance of the 10Gbit/s format conversion system areevaluated and discussed by simulation Theoretical analysis. The
proposed scheme can potentially useful in optical switching and theinterconnection between backbone network and access network.

[4] S. Deléglise et al., Nature 455, 510 (2008); L. Lutterbach and L.
Davidovich, Phys. Rev. Lett. 78, 2547 (1997).

8554-39, Session 9

An all fiber source of pulsed twin beams in
the telecom band
Xueshi Guo, Nannan Liu, Xiaoying Li, Liang Cui, Tianjin Univ.
(China)or the practical continuous variable quantum information processing,
the availability of a simple system to produce large amount ofsqueezing is vital. In this paper, we present an all-fiber source oftwin beams by using a fiber optical parametric amplifier (FOPA). The
broadband FOPA consisting of 300 m dispersion shifted fiber and a
10/90 fiber coupler is pumped with a mode-locked fiber laser, and thewavelengths of twin beams with pulse duration of a few picoseconds
are in the 1550 nm telecom band. When the seeded parametric gain is
about 56, the intensity noises of the amplified signal and generated idler
pulses are found to be correlated by 30 dB, while the subtracted noise
drops below the shot-noise limit by 3.1 dB (10.4 dB when corrected
for losses). To the best of our knowledge, this is the highest noise
reduction obtained in a FOPA. Thorough analysis reveals that highorder four wave mixing, Raman effect, and extra noise of the pump andseeded signal are key factors preventing the twin beams from further
noise reduction. By engineering the phase matching condition of the
FOPA and suppressing the noise of laser system, an even higher noise
reduction will be feasible. The investigation shows a pulse pumped
high gain FOPA provides an efficient and simple means to generatecontinuous variable quantum state.

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Conference 8555:
Optoelectronic Devices and Integration IV
Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8555 Optoelectronic Devices and Integration IV

8555-1, Session 1

8555-3, Session 1

Making the mid-infrared nano with designer
plasmonic materials (Invited Paper)

Optical interactions between silver
nanocubes and two-dimensional silver
gratings studied by surface enhanced
Raman scattering

Stephanie Law, Jonathan R. Felts, Univ. of Illinois at UrbanaChampaign (United States); Viktor A. Podolskiy, Univ. ofMassachusetts Lowell (United States); William P. King, Daniel
M. Wasserman, Univ. of Illinois at Urbana-Champaign (UnitedStates)At short wavelengths (visible or near-infrared), the use of gold or silver
as constituent materials in plasmonic or meta-material structures has
allowed for the demonstration of a wide variety of novel phenomena.
However, the extension of these phenomena to longer wavelengths,
such as the mid-infrared (mid-IR), an important wavelength range forsensing and defense applications, requires more than a simple scalingof geometries. This is because at longer wavelengths, the real partsof the permittivites of gold and silver are quite large in magnitude, andthese metals behave almost as perfect electrical conductors, giving
significantly different near-field behavior for plasmonic and metamaterial
structures. However, scaling is possible if new plasmonic materials,
whose permittivities at long wavelengths mimic those of gold and silver
at shorter wavelengths, can be developed. In this presentation, we will
demonstrate that epitaxially-grown, highly-doped semiconductors canbe used as designer mid-IR plasmonic materials across a broad rangeof mid-IR wavelengths. At wavelengths where our materials’ permittivity
approaches zero, so called epsilon-near-zero (ENZ) wavelengths, wewill show that these designer ENZ materials can enhance transmissionof light through subwavelength apertures. At longer wavelengths, ourmaterials behave, in the mid-IR, similar to traditional plasmonic metals(gold and silver) at shorter wavelengths. This is evidenced by theirability to support localized surface plasmons, which we demonstrate,using both far field FTIR spectroscopy as well as a novel near-fieldmeasurement technique for spectral and spatial mapping of thelocalized resonances.

8555-2, Session 1

Polymer based plasmonic elements
investigated with leakage radiation
microscopy (Invited Paper)
Douguo Zhang, Univ. of Science and Technology of China(China)Recently, dielectric loaded surface plasmons (SPs) elements are
inducing highly interesting in the field of nano-optics, which arecomposed of dielectric nanostructures fabricated on a metallic thinfilm. In this talk, we will present our recent work in this field. Polymer
nano-structures are fabricated on a silver film by the EBL and laserinterference lithography. These nano-structures are used to manipulate
the behaviors of the SPs, such as converging, diverging, and guiding
the propagation of SPs in sub-wavelength scale. Dye materials doped
PMMA structures are also fabricated on the silver film, which provides
a choice to realize active plasmonic elements. On the other hand, theinteraction between the fluorescence molecules and SPs will give rise
to some new optical phenomena, such as directional fluorescenceemission, anisotropic fluorescence emission. We will also introduce
some of our recently progress in super-resolution lithography taking
advantages of polymer materials.

Qiang Fu, Univ. of Science and Technology of China (China)
In the present work, we fabricate some different period two dimensional
metal gratings through two beams interference photolithography,
and synthesis about 50nm silver nanocubes by chemical reduction
method. The surface enhanced Raman scattering (SERS) intensity ofrhodamine6G in different structures is compared . The results show that
the SERS intensity is much weaker when there is only silver film than 2D
silver gratings and silver nanocubes composite structure. Furthermore,
we find that the SERS intensity on the ridge of the 2D silver gratings isalso weaker than that in the groove. We attribute these results to thecoupling of localized surface plasmon (LSP) and propagating surface
plasmon (PSP) and the electric field enhancement in the cavity (groove).

8555-4, Session 1

Subwavelength dielectric-loaded plasmonic
waveguides based on a core-shell structure
Bing Shen, Yongqing Huang, Xiaomin Ren, Qi Wang, Xia Zhang,
Xiaofeng Duan, Beijing Univ. of Posts and Telecommunications(China); Dong Zhang, Beijing Univ. of Posts andTelecommunications (China); Jinhua Hu, Beijing Univ. of Posts
and Telecommunications (China)
Surface Plasmon Polaritons (SPPs) have attracted great attention
due to its ability to break the diffraction limit and thus greatly
minimize the dimension of optical devices. In this paper, a new
type of subwavelength plasmonic waveguide based on a core-shellstructure has been proposed. A three-layer structure in the shape ofsemi-cylinder arranged on a dielectric substrate forms the proposed
waveguide. The inner core layer, middle gap layer and the outercladding layer is made of metal, dielectric with lower permittivity
and dielectric with higher permittivity, respectively. As with the metal
properties to tightly confine light near its surface, the middle gap layer
serves as the channel guiding the light.
It is demonstrated that a modal area as small as l2/3600 can beachieved in the proposed waveguide, which is far smaller than that in
the traditional dielectric-loaded plasmonic waveguide. Meanwhile, apropagation length is calculated as large as 100µm, large enough forthe application of guiding light in Photonic Integration Circuits. Thus abetter trade-off in terms of confinement and propagation is achievedin the proposed waveguide. In addition to that, it is demonstrated thata ring resonator based on the proposed waveguide exhibits a perfectperformance with a 1.8nm 3dB-bandwidth and 23dB extinction ratio.
The simulated results reveal that ring resonator based on the proposed
waveguide could exhibit better performance than that based on the
dielectric or traditional dielectric-loaded plasmon waveguide withbandwidth larger than 3nm and extinction lower than 20dB.

8555-5, Session 2

Random optical traps enabled by metallic
nano-island (Invited Paper)
Ho-Pui A. Ho, Zhiwen Kang, Haifei Lu, Haixi Zhang, The
Chinese Univ. of Hong Kong (Hong Kong, China)

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Optoelectronic Devices and Integration IV
We report a simple approach to generate plasmonic optical traps inmetallic nano-islands generated by annealing nanometer thick gold
films. The plasmonic substrate is first immersed in an aqueous medium
containing silver nanoparticles and a Raman tag (4-MBA). Upon
illuminating the islands with a focused 785 nm laser beam, surface
enhanced Raman scattering (SERS) occurs due to the formation of
nano-gaps between the silver nanoparticles and the traps. Raman
signals from 4-MBT slowly increases with time as the nanoparticles
migrate into the optical traps. The trapping process is switchable. This
technique might be useful for high sensitivity detection of molecules.

by standard dip coating technique on clean microscopic glass slides.

8555-6, Session 2

Waveguides were characterized by prism coupling technique using
He - Ne Laser. Multilayer structure has also been fabricated using same
technique. Four layer dispersion curves have been generated using
formulation of Sun and Mullar. Theoretical dispersion curves have been
generated for both the polarizations. It has been clearly observed thatfirst few modes are guided for both TE and TM polarization thus can beused as mode filter. The results show good agreement with theoreticalones. Another important result is that four layer optical guides exhibit
relatively low propagation losses. It is also suggested that evanescentportions of the field distribution study can lead to evaluate the opticalproperties of the surroundings and as such can be exploited for sensor
applications.

Heterojunction Si-SiC photodiodes for hightemperature operation

8555-9, Session 2

Joel Therrien, Daniel Shmidt, Lian Dai, Univ. of Massachusetts
Lowell (United States)
Silicon-Silicon carbide based heterojunction photodiodes were
fabricated using a novel process for making semiconductor grade SiC
from polymer sources. The diodes were fabricated by spin coating the
precursor polymer [Poly(silylenemethylene)], dissolved in hexanes onto
a boron doped [100] silicon substrate to produce a film with thickness
in the range of 0.5-1 microns. The substrates were heated in an inert
tamosphere to 900 °C to pyrolize the polymer into silicon carbide. The
SiC was doped n-type by ion implanting nitrogen with dopant densities
in the range of 10^17/cm^3. The diodes showed excellent rectifying
properties with a turn on voltage of ~ 4V. The diodes were tested foropen cicuit photovoltage and short circuit photocurrent response as
a function of temperature. A commeercial silicon photodiode wastested uner the same circumstances for comparison. At temperatures
exceeding 100 °C, the commercial diode was overwhelmed bythermally generated current. In comparison, the heterojunction diode’s
performance did not diminish for temperatures up to 170 °C.

8555-7, Session 2

A simple ultra-wideband dual-core SPSM
PCF
Min Liu, Li Dan, Chongqing Univ. (China)
A simple dual-core single-polarization single-mode (SPSM) photonic
crystal fiber (PCF) is proposed. We find that the PCF has simple
structure which is easy to manufacture, and the SPSM region is
ultra-wide. Also, the wide width of the SPSM region and the short
coupling length can be tailored by adjusting the design parameters.
The most important feature is that it can obtain simultaneous lowloss transmission of 1.30/1.55µm in the SPSM region, which is very
attractive for optical communication systems. Based on the analysisof the coupling characteristics, we demonstrate that the wavelength
division demultiplexer (WDDM) can be realized by using this kind of
PCF.

8555-8, Session 2

Multilayer polymeric mode filter using
K-resin for optical integrated circuits
Kailash N. Tripathi, Galgotias Univ. (India)
There have been often problems of multimodes in any opticalcomponent. Mode Filter is an optical component used to suppress
the higher modes and allow the basic mode to propagate undamped .
Optical mode filter is an optical waveguide formed by higher refracting
material disposed near a flat waveguide core. Two buffer layers arelocated opposite the waveguide core and one is formed with a thinned
region to function as a filter for higher modes being transmitted throughwaveguide. Thin film multimode waveguides of K - resin were fabricatedCompact terahertz wave broadband
reflectors based on silicon photonic crystal
slabs
Xiaolong Hao, Zexuan Qiang, Zhiyong Chen, Yanmin Zheng,Junzhen Jiang, Fujian Normal Univ. (China); Xiyao Chen,
Minjiang Univ. (China); Yishen Qiu, Fujian Normal Univ. (China)
Terahertz (THz) waves with a frequency of 0.1THz-10 THz offer manypotential applications like medical imaging, security screening, chemicalsensing and astronomy. There is a high need to control THz waves
in a compact integrated circuit for these applications, especiallyfor compact THz sources. Broadband reflectors (BBRs) with highreflectivity are the essential components to construct the laser cavity.
For visible and near IR, they can be typically realized by using either
stacked dielectric films with glassy materials like SiO2, TiO2, and ThF4
or metal films. However, such materials will not work in THz waves due
to high absorption loss.
Here, we report a compact THz wave BBR based on the effect ofguided mode resonance in photonic crystal slabs (PCSs) wherethese in-plane guided modes are strongly interacted with verticalradiation modes due to phase matching provided by the periodic
lattice structure. By properly controlling the design parameters, verybroadband reflectors can be obtained. Square-lattice air-hole PC
pattern is fabricated in silicon material due to its high transparency in
THz wave. A novel method based on a map of localized bandwidth withdefined reflectivity is introduced to analyze the impact of normalized
thickness and hole size. The rigorous coupled-wave analysis (RCWA)
technique is then applied to analyze its performance. The numericalsimulations show that the proposed configuration can offer abroadband frequency range from 2.27THz to 2.89THz with beyond 95%
reflectivity.
This work has been partly supported by the Natural Science Foundationof Fujian Province of China under No.2012J01253.

8555-10, Session 2

Absorption modulation enhancement of azopolymer film induced by plasmonic field
Xiang Xian Wang, Univ. of Science and Technology of China(Chile)A thin photochromic film on top of the resist layer can be used asa virtual mask to fabricate super-resolution lithography patterns(science 2009,324,917). In this letter, based on the azo-polymer, theabsorption intensity of the 365nm LED is modulated by 532nm laser,
the modulation degree reaches to 87%.When the metallic nanoparticles
are included in the polymer film, the modulation degree is significantly
higher than that without the nanoparticles in the same intensity of
532nm laser due to the field enhancement of plasmons’ excitation. The
absorption modulation features of the polymer film are favorable for thefurther smaller nanolithography.

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Conference 8555:
Optoelectronic Devices and Integration IV

8555-11, Session 3

Tabletop ultrafast X-ray “laser” advancing
nanophotonics under unprecedented spatial
and temporal resolutions (Invited Paper)
Xiaoshi Zhang, Kapteyn-Murnane Labs., Inc. (United States)
Bright and short pulse high harmonic generation beams in the EUV
and soft X-ray range of the spectrum promises breakthrough fornanoscience and nanotechnology. X-rays are unique in their ability
to probe the electronic or spin state with element-specificity inmolecules and materials, because the position of the characteristic
x-ray absorption edges of individual elements is sensitive to the local
environment and structure. Ultrafast x-rays can capture the coupledmotions of charges, spins, atoms and phonons by monitoring changes
in absorption or reflection that occur near these edges as a material ormolecule changes state or shape.
In our labs, we developed table-top, bright, coherent and ultrafast
x-ray “laser” source based on high harmonic generation using hollow
core fiber. To enhance the efficiency of high harmonic generation,
we developed all photonic phase matching technique using counterpropagating light and achieved >140 X enhancement of harmonic
generation at ~ 70 eV. This technique can be applied essentially to
any harmonic order and potentially enhance the efficiency by manyorders of magnitude. Most recently, we demonstrated high harmonic
generation into the x-rays of the spectrum by converting 5001 mid
IR photons into one X-ray photon at 1.6 keV with spectral bandwidth
supporting <1 attosecond (1E-18 s) pulse duration. In the work, we also
showed that in order to achieve higher order harmonics, longer driving
laser wavelength is desired. Combining all these technologies promisesa table-top bright, coherent and ultrafast x-ray “laser”.
Finally, we present a few nano photonics and nano material science
applications that were developed at our laboratories using this lightsource. All these new achievements advance nano photonics and nanomaterial science into the x-ray regime with the capabilities to achieve
sub-nanometer spatial and sub-femtosecond temporal resolutions.

8555-12, Session 3External cavity based single mode FabryPérot laser diode and its application towards
all-optical digital circuits (Invited Paper)

locking and are used for realizing all-optical logic gates and some digital
combinational blocks at the data rate of 10 Gbps.

8555-13, Session 3

Vector beam fiber laser based on few-mode
FBG
Biao Sun, Anting Wang, Lixin Xu, Chun Gu, Hai Ming, Univ. of
Science and Technology of China (China)
We propose and demonstrate a single-wavelength all-fiber laser using
few-mode fiber Bragg grating, generating high quality vector beams
including both cylindrical vector mode TM01 and TE01,and hybrid
mode HE21 odd and even mode. And the four polarization states canbe switched by adjusting fiber polarization controller in the fiber laser
cavity. The fiber laser operates at as single wavelength of 1053 nm witha 3 dB lindwidth of less than 0.1 nm, signal-to-background ratio of 50
dB.

8555-14, Session 3

Research on pattern-induced transparent
conductive films
Xiaohong Zhou, Zongbao Fang, Heng Zhang, Linsen Chen,
Soochow Univ. (China)
Indium tin Oxide (ITO) is widely used in touch panel as conductive
material. However, it is fragile and low transparency in low resistance.
In this paper, a new non-ITO transparent conductive film (TCF) has
been proposed. Micro-nano structured patterns are designed to induce
the nano silver particles and can form the circuit of touch panel sensor
conveniently. Patterns are fabricated by nano imprinting technology
to form micro grooves on flexible films such as PET. And then nanosilver particles are filled in the grooves which constitute the conductive
area of the TCF. The ratio of the line width to line period can influence
the optical transmittance and sheet resistance. The relationshipbetween the optical properties of the TCF and the parameters of the
micro grooves such as the depth, the width, and aspect ratio will be
investigated. Experiment results show the transmittance can be 87%
and the square resistance can be less than 10 W/sq. The new material
has a good performance for a large scale touch panel display and thefabrication process is high throughput and low cost for touch panel.

Bikash Nakarmi, KAIST (Korea, Republic of)All-optical signal processing is of great interest as they posses many
advantages such as electromagnetic interference free, high data rates,transparency and others. All-optical logic gates and combinational
circuit are one of the key elements of any optical systems andsubsystems including signal processing, computation and control
circuits where electromagnetic interference posses a great threat.
Various techniques have been proposed for implementing different logic
gates and digital circuits which are based on Er-doped optical amplifierand periodical poled LiNbO3, semiconductor optical amplifier (SOA);
and others have been reported based on injection locking of FP-LDs.
SOAs are more popular due to its advantages of speed, integrality andBoolean logic capability. But SOAs require more driving current of about
200 mA and expensive. Besides, SOAs need additional probe beam forrealization of optical devices and units.
FP-LD based logic gates are much promising than others as it is simple,
less expensive and consumes low power. Single mode (SM) FP-LD
posses more advantages than the commercialized FP-LD as it has
self locking dominant mode which removes the necessity of additional
probe beam. Thus, using SMFP-LD provides the simpler and cheaper
solution.
In this paper, we introduce different techniques of injection locking
for suppressing the dominant mode of external cavity based SMFPLD which can be used for realizing different digital circuits. Power
management schemes are introduced for different form of injection

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8555-15, Session 3

Emission properties of single deep
confinement potential QD-cavity system
under incoherent excitation
Huan Guan, Peijun Yao, Wenhai Yu, Pei Wang, Hai Ming, Univ.
of Science and Technology of China (China)
Single quantum dot-cavity system with a deep confinement potential
quantum dot is detailedly investigated, with both s- and p-exciton
incoherent pump. Through gradually increasing pump rate (about
0.0001/ps~12/ps), the mean photon number shows a lineardependence on pump power, the photon probability distribution,
characterized by g(2)(0), transforms from antibunching to bunching
through Poisson, and the spectra go from the doublet to a singlet, thelinewidth shows clear reduction in the lasing region. If we increase
pump rate further, the mean photon number decreases monotonically tozero, g(2)(0) reaches its maximum value 2, and all the electrons stack at
upper lasing level, indicating thermal light generation. The results show,
the deep QD-cavity system under s- and p-exciton pump can generatelaser although it is not an ideal coherent light, and with only p-exciton
pump considered, in spite of the coherent light generated, this pumpmethod is unreasonable to simulate the experimental conditions for the
negligible energy spacing between s-exciton and p-exciton.

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Optoelectronic Devices and Integration IV

8555-17, Session 4

Opto-DMD-based tunable triple-channelwavelength fiber laser
Di Zhang, Binbin Yan, Kuizhi Huang, Qiang Yang, Beijing Univ.
of Posts and Telecommunications (China); Xiao Chen, Minzu
Univ. of China (China); Gengxiang Chen, Beijing Jiaotong Univ.
(China)A novel approach employing a digital-micromirror-device (DMD) toachieve a high stable tunable triple-channel-wavelength fiber laser
structure is experimentally demonstrated. The control system ismaintained by an embedded computer incorporating a FPGA circuitboard. A graphical user interface (GUI) is designed for the usage ofinteraction and calibration. When a required wavelength is enteredin the command line on the embedded pc, a corresponding grating
image will be generated and loaded to the FPGA board, the pixel
data is transmitted to DMD through a low voltage differential signaling(LVDS) interface with high speed. At the same time, the loading mode
command is sent to DMD Power and Reset Driver (DAD2000) to reset
the pixel array on DMD. As appropriate steering grating is formedon DMD surface, only the needed waveband of the ASE spectra will
be selected and coupled into the fiber collimator array, while others
are dropped out. There are three gratings can be generated at a timeand hence a triple-channel function can be realized. According to aserious of experiments, there exists a linear relationship between thedigital grating position and output laser wavelength, which makes
it quite convenient to determine the linear coefficient just by using
the calibration function on GUI when environment has changed. The
output power at every channel is regulated separately by a polarizationmaintaining EDFA using an automatic power control (APC) system.
GUI can analyze the received data from three channels and display thecurrent output power on the control panel. Besides, a required output
power can be achieved through the communication between GUI and
EDFA. Experimental results show the laser line-width is 0.02nm witha facile tuning ability of 0.08nm per step over C band. The stability is
indicated by the output power uniformity of 0.01mw during one hour
under room temperature.

8555-18, Session 4

Tunable high-power multi-wavelength
double-clad fiber laser
Jie You, Pengbo Xiao, Xin Wang, Long Huang, National Univ. of
Defense Technology (China)
Multi-wavelength fiber lasers are under intense research due to theirpotential in many application fields like wavelength-division-multiplexing
communication, fiber-based sensing, ranging, microwave photonics
and terahertz generation, etc. In previous literatures, various multiwavelength fiber lasers have been realized. However, most of whichhave employed single-clad rare-earth doped fiber pumped with singlemode laser diode, the output power is limited by the available laser
diode (600 mW for the time being). Multi-wavelength double-clad fiber
laser is expected in many application fields that requires higher laser
power.
In this manuscript, we will present our detailed investigation on tunablehigh power multi-wavelength double-clad fiber laser pumped by highpower multimode laser diode. The fiber laser is constructed in a ringcavity. A multimode laser diode with 8 watt output power is employed.
The active fiber is double-clad Yb-doped fiber, which had a 10 µm
core diameter and 125 µm inner cladding diameter. The NA of thecore and the inner cladding of the double-clad fiber is 0.08 and 0.46,
respectively. The active fiber is clad-pumped by the lased diode via a
7x1 pump combiner (only one pump port is employed). By adjusting
the polarization-controller inside the cavity, the laser can operate at
single-wavelength, dual-wavelength and triple-wavelength regime.
The maximal output power is 5.5 watt and the conversion efficiency is
68.8%. Long-time observation ensures that the laser has an excellent

scalability. The output power can be scaled to multi-tens watt level byadding more pump diodes.

8555-19, Session 4

All-optical QPSK signal regeneration basedon XPM in semiconductor optical amplifier
Yueying Zhan, Min Zhang, Beijing Univ. of Posts andTelecommunications (China); Mingtao Liu, Beijing Univ of Posts
and Telecommunications (China); Lei Liu, Xue Chen, Beijing
Univ. of Posts and Telecommunications (China)
A scheme of all-optical QPSK signal regeneration is proposed whichbased on cross phase modulation (XPM) in semiconductor opticalamplifier (SOA) with subsequent an optical filter. A QPSK signal isgenerated based on an IQ modulator, and the QPSK signal is distorted
after 100km fiber transmission. The QPSK signal is distorted by
the negative chirp after fiber transmission due to the group velocity
dispersion (GVD) and the self-phase modulation effect of the fiber, andthen the distorted QPSK will be regenerated due to the positive chirp
which is induced by XPM in the SOA which is discussed by theoreticalanalysis. In our system, the SOA would works at the deep saturationand the cross gain modulation (XGM) can be mitigated and no phase
distortion will be introduced during the amplitude regeneration. Fromthe simulation results, the BER of the regenerated QPSK signal makes
better when the clock and distorted QPSK signal power are lower
values and the current of SOA is higher value due to the XPM effectin the SOA and the average power of distorted QPSK signal andclock signal are set -5dBm and 10dBm. The amplitude noise of the
distorted signal can be suppressed significantly, and the clear and open
eye diagrams can be obtained. A power penalty 2.3dB is improved
after QPSK regeneration with the receiver sensitivity of -30.7dBm.
Simulations and theoretical analysis are conducted to validate thefeasibility of the proposal.

8555-20, Session 5

All-optical modulation based on side mode
injection locked multi-mode Fabry-Pérot
laser diode (Invited Paper)
Jianwei Wu, Chongqing Normal Univ. (China)
Fabry-Perot laser diodes (FP-LD) are the most common type of diodelaser, where two mirrors are separated by a gain medium. In reality, theFP-LD has attracted significant attention in optical network becauseof the rich nonlinear, low power consumption, and cost effective.
To date, the FP-LD based optoelectronic devices were successfully
demonstrated in various applications such as optical switching, logic
gates, wavelength conversion, and so on. Even so, some potential
applications are not still explored and proposed based on the FP-LD
element. To promote its role in optical technology, the FP-LD based
all-optical modulation is presented and investigated in this paper, inwhich the corresponding gain modulation effect is main influence on
causing the modulation behavior. Of course, it is well known that allkinds of optical modulation technologies have already reported basedon the silicon waveguide , silicon core fiber, and silicon microring
resonator, etc. In these literatures, both the high power levels andcomplex configurations were introduced and presented so that it isvery difficult to reduce the power consumption and simplify the device.
Compared to the previous reports, the FP-LD based optical modulation
can overcome some limitations, in which the modulated outcome signal
with large modulation depth can be achieved under the condition of
milliwatt power level.

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Conference 8555:
Optoelectronic Devices and Integration IV

8555-21, Session 5

Comparison on the accuracy and sensitivityof hole-based solar sensor under gray scale
and binary configuration
Chung-Jen Ou, Yo Yuan Liu, Hsiuping Institute of Technology(Taiwan)Solar tracking device becomes the major concerns for energy research
and application. The basic hole type mask can provide an easy andelegant approach to activate the sensors below the device. However,the configurations and and interactions between the mask arrangement
and the light sensors are critical for various applications and the costeffective considerations. Furthermore, details analysis and sensitivitiesof the illuminating directions are a key success for a more advanced
adaptive tracking system. In this paper we report the sensitivity andtolerance of the holes based device. The comparison of the signals forgrey scale level and the binary type are demonstrated. We proposed
two dimensionless parameters between the mask patterns and thesensors for revealings the performance of the hole based solar sensor.
A 0.5 degree accuracy for grey scale type sensor is possible to achieve,
however an average of 2 degree tolerance is recommended for grey
scale electronic circuits. As for low cost binary type configurations,designed patterns can achieve 5 degree accuracy under the same
number of sensors below the mask.

8555-22, Session 5

All-optical amplitude regeneration for PDM
RZ-DPSK signal using a semiconductor
optical amplifier
Yu Yu, Huazhong Univ. of Science and Technology (China);
Dexiu Huang, Wuhan National Lab. for Optoelectronics (China)
and Huazhong Univ. of Science and Technology (China)
The amplitude-only regeneration, which is usually simple and costeffective, is very attractive for the phase modulated signal, since theamplitude noise will transfer to the phase noise due to the GordonMollenauer effect during the transmission. On the other hand, thepolarization division multiplexing (PDM) technique also attacks more
and more people in all-optical communication system as it can double
the spectral efficiency and data capacity.
In this paper, we propose and demonstrate all-optical parallel amplitude
regeneration for PDM return-to-zero differential phase-shift keying(RZ-DPSK) signal, using a single semiconductor optical amplifier (SOA).
The regeneration is based on the cross-phase modulation (XPM) in
the SOA. The input two polarization tributaries are phase modulated
by a synchronous optical clock signal with large power and optimal
polarization state. A subsequent offset filter is used to extract the
specific part of the broadened spectra to perform the noise suppressing
function. The PDM RZ-DPSK signal at 2*40 Gb/s can be amplitude
regenerated with a power penalty of -1.5 dB.

8555-23, Session 5

Two-wavelength switching in an asymmetric
Fabry-Perot resonator with InGaAs/InP
based multiple quantum well structure
Lokanath Mishra, Indian Institute of Technology Kharagpur(India); Rajib Pradhan, Midnapore College (India); Prasant K.
Datta, Indian Institute of Technology Kharagpur (India)
Wavelength switching between two optical signals at different
wavelengths has been studied theoretically in an asymmetric FabryPerot resonator (AFPR) operating simultaneously in reflection and

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transmission mode. The AFPR, embedded with a semiconductor
saturable absorber exhibits high nonlinearity, which makes this device
attractive for all-optical signal processing. The bistable characteristic ofthe device has been studied in reflection and transmission incorporating
both optically induced thermal effects and Kerr-nonlinearity. In thepresent work we have studied the switching of a signal beam at
1549nm by another control beam at the cavity resonance wavelengthof 1550nm using bistability of the device. In our simulation we have
fixed the input intensity of the signal beam at Iin2 = 0.2Isat, and isoperated in reflection mode. Initially the control beam (Iin1) is at ‘OFF’
output state while the signal beam is at ‘ON’ output state for an input
Iin1=0, operated in transmission mode. On gradually increasing the
input power of the control beam the carrier concentration within thecavity increases, this modifies the absorption and refractive index of thesaturable absorber, results in change of the output intensities of bothsignals. The simulated result shows that the output of the control beamswitched abruptly from an OFF to ON output state (counter clockwise
bistability) at Iin1=1.34Isat, while the reverse effect observed in case of
the signal beam. Due to its comparatively small carrier recombination
time (~2ps), the AFPR could be a potential device for high speed
switching.

8555-24, Session 5

Optical generation of millimeter-wave basedon single-mode fiber ring cavity
Haiyan Chen, Lilin Chen, Cong Chen, Yangtze Univ. (China)
Recently, optical generation of millimeter waves has attracted a
lot of attention, duo to its high speed, low cost and high reliability.
Compared with traditional high-frequency radio and coaxial cabletransmission system, The combination of millimeter wave and opticalfiber communication, radio over fiber(ROF), is a good solution to
improvement of information capacity. One of the key of ROF systemis the generation of millimeter wave. With the first microwave was
generated by optical inject locked technology in 1985, more and more
modulation techniques are found out and applied to millimeter wave
generation. High frequency millimeter signal has a big phase noise inheterodyne method. The center wavelength of optical fiber grating must
accurately match with the obtained millimeter wave signal wavelength.
Recently, optical generation of millimeter-wave based on active ringcavity and microfiber ring resonator was reported by CHU and Yu
Zhang etc, respectively. But both of them did not consider the impact offiber-optic birefringence.
In this paper, a novel photonic generation of millimeter waves basedon the birefringence in a single mode fiber ring cavity is studied
theoretically. The effects of straight- through coupling coefficients,
phase delay factor, loss factor and refractive index difference on
millimeter wave signal are discussed.

8555-35, Poster Session

Tunable erbium-doped fiber ring laser basedon an all-fiber filter
Xiaochun Ji, Zhigang Cao, Benli Yu, Anhui Univ. (China)
We demonstrate a tunable erbium-doped fiber ring laser based on an
all-fiber filter. The filter consists of an optical circulator, a fiber loop
mirror(FLM) and a polarizer which is spliced to a segment of polarization
maintaining fiber (PMF) at the angle of 45° with respect to the fast axisof the PMF.
In the experiment, the laser oscillates when the pump power is 110mw.
the tunable laser is achieved when the PC2 is adjusted in the laser
cavity. The wavelength can be tuned from 1553.92 to 1560.1nm at a
discrete step of ~0.35 nm, which is related to the wavelength spacingof all-fiber filter, and the side mode suppression ratio is over 38 dB. The
output power difference is less than 1.2 dB .The mechanism of tunablewavelength can be explained as below. The light which is reflected by

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the FLM returns to the polarizer and converts into linearly polarized
light. When in the ring cavity, the polarization states is changed by
PC2 and the birefringence effect of fiber in the cavity. The changesof different wavelength are different, and the different wavelength will
experience different loss when the light passes through polarizer again.
That is to say, the control on the polarization states of the different
wavelength by PC2 is equivalent to the control on the loss of different
wavelength. Only the wavelength have the lower loss can oscillate.
Thus we achieve the tunable erbium-doped fiber laser by adjusting PC2

8555-37, Poster Session

Addressable wide dynamic range and highprecision digital control device for adaptive
liquid crystal microlenses array
Xin Chen, Huazhong Univ. of Science and Technology (China);
Shengwu Kang, Wuhan Polytechnic Univ. (China); Xinyu Zhang,
Huazhong Univ. of Science and Technology (China); An Ji,
Institute of Semiconductors (China); Changsheng Xie, Wuhan
National Lab. for Optoelectronics (China); Tianxu Zhang,
Huazhong Univ. of Science and Technology (China)
Traditional optical microlenses have certain limitations because of the
fixed optical properties. Current research demonstrates that liquid
crystal (LC) is a kind of excellent electro-optic materials, because
they have relatively strong electronic and optical anisotropies, andtheir optical properties can easily be shifted by external electric fields
applied. Compared to traditional optical microlenses, the focal lengthof LC microlenses can be changed with the variance of the alternating
signal voltage applied over the LC microlenses. A high precise andrelatively wide range adjustable output voltage signal can be utilized
to perform well in the controlling of LC microlenses array because thevariance of focal length can be set in a relatively large range when thevoltage of the signal is changed in a relatively large dynamic region.
According to the above demands, a digital control device with a widerange adjustable precise output voltage is designed and realized. Its
output voltage range can be changed continually from 1 VRMS to48 VRMS, and the voltage output precise is ~10 mVRMS, and theoutput signal waveform can be chosen as a sinusoidal, triangular, or
square wave, and its frequency range can be set from 1Hz to 100 KHz.
The realized controlling system has independent 16 channels, which
independently control any one of 4?4 liquid crystal microlenses array,so all the 16 parts of 4?4 array is addressable, which is very importantto performing high performance imaging detection of object in complex
circumstance. Using this device fabricated by us, we can independently
control the 4?4 array to focusing partial incident light beams that areinterested to detect or recognize object, according to the characteristics
of light intensity distribution over the photosensitive array. That meansthat the LC microlenses is attached with the features of adaptivefunction and have a broad application perspective for detection andimaging apparatus.

8555-38, Poster Session

Wide FOV receiving device for indoor visible
light communication systems based on the
MIMO principle
Xue Ming Liu, Nanjing Xiao Zhuang College (China) and Nanjing
Univ. of Posts and Telecommunications (China); Zhong-cheng
Liang, Xuying Wang, Qiuqi Ju, Nanjing Univ. of Posts andTelecommunications (China)
Visible light communication (VLC) is expected to be the next generationof indoor wireless broadband access technology. In order to achieve
high data transmission rates, the multiple input multiple output (MIMO)VLC is proposed to break the bandwidth limitation due to the slow

response time of LED devices, MIMO-VLC offers the potential totransmit data in parallel between multiple sources and detectors. In
addition, MIMO processing removes the need for precise alignmentof transmitters and receivers, if the channel matrix is known and offull rank. Therefore, MIMO provides a solution to the design of wide
field-of-view (FOV) receiving device for indoor VLC system, whichis expensive if traditional optical components are used. This paper
demonstrates the feasibility of such FOV receiving device with an
integrated four-quadrant detector, and discusses the device properties
in terms of optimal channel capacity, complexity and robustness to
misalignment. A physical model is proposed for system simulation
based on the single lens optical transform. The aim of this effort is todesign and realize the integrated receiving device of wide FOV for LED
visible light communication systems.

8555-39, Poster Session

Liquid crystal microlens with tunable-focus
in focal plane driven by low voltage
Shengwu Kang, Xin Chen, Huazhong Univ. of Science andTechnology (China)
Many modern optical imaging systems require elements with variable
optical power for auto-focus and optical zoom applications, theconventional mechanical approaches are very difficult to implement.
New alternative approaches and materials have been explored toreplace those mechanical elements. Liquid crystal materials havelarge electrical and optical anisotropies, and they may provide hugeelectrically controlled refractive index changes without mechanicalmovements. Multiple attempts have been done to use this phenomenon
for developing tunable focus lenses. To produce lens effect in a LC
layer of uniform thickness, it is important to design an electrodepattern capable of creating an axially symmetrical inhomogeneouselectric field in the LC layer. A LC lens with one hole-patterned and oneplanner electrodes was first realized in 1979, its focal length could becontinuously varied electrically, since then many kinds of LC lens withvarious patterned electrode have been developed. Japanese scientists
developed a LC lens driven by two voltages. One voltage acts as abias voltage, while the other one varies to control the focal length. The
electrode with a circular hole in the center, being separated from the
LC layer by a glass substrate, is divided into four subelectrodes. ThisLC lens could make focus movable both along and off lens axis, butthey need high AC voltage to drive electrode and the two AC voltages
must be in phase. The reason is that the upper electrode is separated
with LC layer by glass substrate, which increases the driven voltage.
Another problem is that the diameter of circular hole is large. According
to these problems, a LC lens with new electrode pattern is designed
and realized. The ITO low and top electrodes are placed face to face,
they are separated by glass spacer, and LC is injected between them.
Because the two electrodes face the LC layer closely, this design could
decrease driving voltage largely. The low electrode is designed with one
hole-pattern. The top electrode is four circle patterns. The diametersof hole and circle are 500um and 160um respectively. Each circle
electrode can focus respectively in the different place in plane, when
the four circle electrodes are driven by different voltage at the sametime, the focus could move off-axis in focus plane, the voltage varies
from o to 20V. So we realize a LC microlens with tunable-focus in focal
plane driven by low voltage.

8555-40, Poster Session

A no adhesive and temperature-independent
package for fiber Bragg grating pressure
sensorHui Wang, Hui Wang, Jun Zhu, Hao Yin, Zhao Zhang, Benli Yu,
Anhui Univ. (China)
In this study, an innovative temperature- independent and no adhesive

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Conference 8555:
Optoelectronic Devices and Integration IV
package for FBG pressure sensor was designed. The FBG sensor
package structure to compensate for temperature deviation bymechanical properties of different metal materials; It was metallized
package with no adhesive using an plating method and laser welding
process. The sensor can be effective to achieve the temperaturecompensation, and to avoid the problems of the aging and hightemperature failure of the adhesive. Strain sensing experiment obtain
good symmetry and linearity within the range of -30 ? ~80 ?.

8555-43, Poster Session

8555-41, Poster Session

Nanosecond, picosecond and femtosecond laser pulse induced
damage thresholds on CCD are investigated in this study. The
thresholds of laser-induced damage on CCD are calculated theoreticallyfor three pulse widths based on the thermal damage model. An
axisymmetric mathematical model is established for the transient
temperature field of the CCD. Experiments are performed to test thedamage thresholds of CCD at various pulse widths. The results indicatethat the damage thresholds obviously increase with the increasing oflaser pulse width. Additionally, the experimental results agree well withtheoretical calculations and numerical simulation results.

Linearly-polarized Yb-doped fiber laser
based on 45-degree fiber Bragg grating
Shenggui Fu, Xiaojuan Liu, Gongxiang Wei, Liping Guo, Xiaolu
Ge, Shandong Univ. of Technology (China)
Tilted fiber Bragg gratings?TFBGs? have drawn a great deal interests
recent years for their special structure and advanced properties.
45 degree TFBGs have been proved to be of excellent polarization
characteristics.
In the paper, a 45 degree TFBG was fabricated in photosensitive fiber
successfully using phase mask technique. The polarization-dependent
loss characteristic of the TFBG was experimentally researched in thepaper using a special measurement system. The measurement results
showed that the 45 degree TFBG could act as a polarization possession
element. Based on the 45 degree TFBG, a linearly-polarized Yb-doped
fiber laser was demonstrated. The polarization-extinction ratio of theoutput laser is about 30 dB. The output power was about 5mW with thepump power of 120mW. The central wavelength of the laser is 1064nm
and the wavelength bandwidth was about 0.1nm. Being a polarization
device, the TFBG has the advantages of in-fiber, compact, goodpolarization capability and low price.

8555-42, Poster Session

Photoemission stability of negative electron
affinity GaN photocathodeJunju Zhang, Nanjing Univ. of Science and Technology (China)
With the rapid development of lithographic manufacturing andultraviolet (UV) detection technology, high performance
UV photocathode is needed urgently. GaN based photocathode has
become an attractive candidate due to its wide band gap, stablephysical and chemical properties, high quantum efficiency (QE), and low
dark current. GaN photocathode activated by Cs/O can reach a higher
QE because of the negative electron affinity (NEA), and how to keep
photoemission stability of negative electron affinity GaN phtocathodefurther becomes the important part of our study. the spectral responseand quantum yield curve of reflection mode GaN photocathode justafter Cs/O activation and Cs reactivation was achieved by using theonline multi-information measurement and evaluation system. Also
the attenuation in photocurrent under the radiation of 300 nm light ismeasured every hour. The result indicates that GaN photcathdoe aremuch more stable than narrow band material. The photocurrent peakincreased by 16. 8% after Cs reactivation which demonstrates thereason of the QE attenuation is the Cs desorption on the Cs?O adlayerof surface. This can be explained by a double dipole layer model?GaN(Mg) :Cs?:Cs-O whose stability determines the stability of GaN
photocathode.

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Laser-induced damage threshold of CCD innanosecond, picosecond, and femtosecond
regimesJunyan Hou, Beijing Track and Communication Technology
Institute (China)

8555-44, Poster Session

Research on the impact of extreme
environment on the FBG-based tensile strain
monitoring for CFRP composite structure
Hong-yue Liu, Nanjing Univ. of Aeronautics and Astronautics(China) and Southeast Univ. (China); Da-kai Liang, Nanjing
Univ. of Aeronautics and Astronautics (China); Qing-guo Fei,Southeast Univ. (China)
From the sensitivity of the FBG center wavelength changing withstrain variations on the surface of CFRP composite, we investigate thecorrelation between the mechanical properties of the CFRP composite
tensile specimen and extreme environments (high, low temperatureand hydrothermal environment), that is, the tensile strain of CFRP
specimen after different temperature or hydrothermal environmentchanges and a certain residual strain occurs. By combining FBG and
the effect monitoring of CFRP structure caused by environmental
factors, a FBG-based monitoring method for mechanical propertiesof composite after extreme environments is proposed. The tensile
strain on the surface of CFRP specimen after high-temperature isslightly larger than the one before, and there is a certain residual strain;
there is little effect on the tensile strain of CFRP specimen after lowtemperature; the residual strain coming from hydrothermal environmentis larger. The experimental results numerically showed that the FBGbased mechanical properties monitoring of CFRP specimen has good
accuracy for a wide area.

8555-45, Poster Session

Three-dimensional modeling of nematic
liquid crystal micro-optics structures withcomplex patterned electrodes
Xing Rong, Huazhong Univ. of Science and Technology (China);
Shengwu Kang, Wuhan Polytechnic Univ. (China)
Liquid crystal (LC) is a kind of special liquid material composed ofmolecules with weak orderly orientation distribution. Generally, thefunctional liquid crystal devices demonstrate both the birefringencecharacteristics and special electro-optic property, in which LC
molecules can be easily driven and controlled by the external electricalfields applied. The obvious advantages of LC device are the low signal
voltage, very low power consumption and the electrically tunableoptical property. Currently, it is very attractive to make the micro-optics
structure using liquid crystal material. A micro-optics structure canmake the incident field turned into the anticipant optical output field. In

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order to design and fabricate the micro-optics structure, it is important
to study the relationship between the anticipant optical output field andthe external electrical fields formed by complex patterned electrodeplates. So the first step is to calculate the distribution of LC directors
which determine the distribution of refractive index in LC layers.
In this paper, a three-dimensional (3-D) over-relaxation method is
proposed to model the dynamic response behavior of liquid crystal (LC)directors in nonuniform electric fields. The method is based on FrankOseen continuum elastic theory by using a vectorial representation. Thismethod can deal with liquid crystal structures with arbitrary patternedof electrodes, and it is quite computational stability. Different numericalresults obtained according the method are as follows: (1) the nematic
LC structures with different patterned electrodes applied by a constantvoltage, and (2) the nematic LC structures with different thickness of
LC layer, and (3) the nematic LC structures with different signal voltage.
The typical results include the distribution of LC directors in LC layers,
the distribution of electric potential in LC layers, and the distribution ofphase retardation. The results show that the method can be used toeffectively predict the formation of disclination lines, which has a strong
impact on the performance of LC micro-optics structure.

8555-46, Poster Session

Photoelectric response performance ofnano-graphene film over infrared substrates
Jinhui Gong, Huazhong Univ. of Science and Technology(China)The development of graphene technology indicates that the graphene,
a single atomic-layer of carbon, is a novel two-dimensional material
with extraordinary optical, electronic, and structural properties. With
the special gapless band structure and spectral bandwidth, graphene
can be used in the next generation of IR photodetection and novel
material in other important opto-electronic application. In this paper, wedemonstrate the fabrication and the measurement of special nanographene-detectors for IR radiation. We transfer graphene onto different
infrared wafer including germanium, GaAs, silicon, and quartz. The
system consists of the transferred graphene film over different wafer
and metal electrodes that is fabricated on graphene sheet.With the zeroband structure, graphene generate electron-hole pairs over a broad
range of wavelength including UV, visible range?IR and THz wavelength.
In our studies, the current-voltage relation of the system (certain direct
voltage is applied on through the two metal electrodes) is measured
before and after IR laser irradiation .
As tested, graphene has high optical transmittance in the visible,
IR, and THz wavelength range. We research the current-voltage
performance of the system. When the graphene structure is illuminatedby laser beam of 1.1?m wavelength and 0.9W power, an inflection pointand current gain can be discovered. Because of the low light absorptionof graphene, the photocurrent of the system is limited in about
1~3mA/W under certain voltage. We hold the point that the grapheneand semiconductor form a certain kind of energy Band gap, which
affect the photocurrent generation.

8555-47, Poster Session

Giant laser-induced thermoelectric voltage
in c-axis inclined NaxCoO2 thin films
Shufang Wang, Zilong Bai, Hebei Univ. (China); Shanshan Chen,
Zilong Bai, Hebei University (China)
Layered cobalt oxide thin films exhibit large light-induced thermoelectric
voltage effect due to anisotropic Seebeck effect and have a great
potential for light detector applications. In this paper, we have preparedc-axis inclined NaxCoO2 thin films by the topotaxial conversion method
and studied its light-induced thermoelectric voltage effect by using
an ultraviolet pulsed laser as light source. The incidence direction of
the laser beam was directly perpencular to the film surface. The laser

spot was located at the centre position between the two electrodes
and its diameter was about 2 mm. The induced lateral voltage signals
were recorded using a digital oscilloscope of 500 MHz bandwidth
terminated into 1 Mohm. A giant open-circuit voltage signal with thepeak voltage Vp of tens of voltage was observed when the film surface
was illuminated by the 308 nm pulsed radiation, and the Vp increased
linearly with the inclination angle as well as the laser energy on the film.
The results demonstrate that the c-axis inclined NaxCoO2 thin film hasa great potential application in the detection of weak ultraviolet pulsed
radiation.

8555-48, Poster Session

Drift error anlysis of atomic spin gyroscope
Shuangai Wan, Jiancheng Fang, Yao Chen, BeiHang Univ.
(China)Sensitive gyroscope is used in a wide range of applications, particularly
in inertial navigation. In recent years, with the rapid development of
quantum manipulation and modern optic manipulation technique,the advantages such as high precision and compact size offered by
the atomic spin gyroscope, have attracted a number of researchers
to these fields. Now the atomic spin gyroscope is believed to be thedevelopment trend for the high precision and compact gyroscope infuture. The atomic spin gyroscopes are mainly composed of opticalsystem, signal detection circuitry, magnetic shielding and magnetic
compensation system, which produce errors under working conditions
inevitably. Understanding the influence of magnetic field and light fieldon the performance of atomic spin gyroscope is important during thedesign of such devices. The basic principle of atomic spin gyroscope
was reviewed and the analysis of error sources presented beganwith the coupled Bloch equations describing the dynamics of atomic
spin gyroscope including magnetic field, light shift and pump-probe
non-orthogonality. It was shown analytically that the first order effectsof the transverse magnetic fields imperfections can be eliminatedby turning the longitudinal magnetic field on the magnetic fieldcompensation point. The effects of longitudinal magnetic field and lightshift imperfections with other terms zeroed contributed only to scale
factor of the atomic spin gyroscope. Furthermore, the effects magnetooptical crystal and magnetic shielding due to temperature drift were
described and according approaches to suppress these errors werealso proposed.

8555-49, Poster Session

Coupling characteristics between
fundamental mode square waveguide andfiber
Fuyuan Guo, Lianhuang Li, Hua Zheng, Yi Wang, Jinrui Ke,
Tiangui Dai, Fujian Normal Univ. (China); Xiaoming Lin, Fujian
Normal University (China)
For the sake of clarifying the rationality of the Gaussian approximation
for fundamental mode square waveguide and fiber, the relationshipbetween the beam propagation factor (M^2) and the structure
parameter is discussed. As the beam propagation factors offundamental mode square waveguide and fiber are very close to theunit in a certain range of the normalized frequency, it is rational that themode field distributions of fundamental mode square waveguide andfiber are expressed by the Gaussian functions approximately.
As the mode field half width defined by second order moment is greaterthan the identical concept defined by differential operator, it is difficult
to confirm which one of them would work better, so the mode field half
width defined by equivalent matching efficiency for fundamental modesquare waveguide or fiber is recommended, it is the geometrical meanof the mode field half widths defined by second order moment anddifferential operator.
The coupling characteristic between fundamental mode square

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Conference 8555:
Optoelectronic Devices and Integration IV
waveguide and fiber is depended on their mode field matching
characteristic. Base on the overlap integral formula of coupling
efficiency and the mode field half width defined by equivalent matchingefficiency, the approximate optimal structure parameters of this couple
system is suggested. And Base on the overlap integral formula ofcoupling efficiency and the real mode field distributions of fundamental
mode square waveguide and fiber, the real coupling efficiency between
fundamental mode square waveguide and fiber is presented.

to 35dB and a boxlike filter response with sharp factor(SF) of 0.68. In
addition a quality-factor of 2961 and a 3-dB bandwidth of 0.52nm areachieved.

8555-50, Poster Session

Xiaojuan Liu, Shandong Univ. of Technology (China)

Variable doping narrow-band response
GaAlAs photocathode the preparation
method of the research
Yuan Xu, Nanjing Univ. of Science and Technology (China)
and Nanyang Institute of Technology (China); Xinlong Chen,
Jing Zhao, Benkang Chang, Nanjing Univ. of Science andTechnology (China); Youtang Gao, Nanyang Institute ofTechnology (China)
In order to avoid the low sensitivity common problem of 532nm
sensitive narrow-band response photocathode, variable doping
narrow-band response GaAlAs photocathode structure is designed. The
photocathode is composed of GaAs substrates, Ga1-x1Alx1As buffer
layer, Ga1-x2Alx2As doping concentration gradient emissive layer and
GaAs protection layer from bottom to top. Among them, exponential
doping method is applied to Ga1-x2Alx2As unit layer from the bottom
to the top. And a preparation methods of GaAlAs photocathode isdeveloped. For the GaAlAs photocathode components which growwell, chemical cleaning, heating purification and (Cs, O) activation are
operated, and ultimately Cs / O activation layer is formed on the surfaceof Ga1-x2Alx2As doping concentration gradient emissive layer. The
highest sensitivity of the photocathode peak response is at 532nm, andthe photocathode quantum efficiency in 532nm peaks at 36%.

8555-51, Poster Session

8555-52, Poster Session

Experimental demonstration of a narrow
linewidth 1120-nm Yb-doped fiber laser
Because of the heat-dissipation characteristics of fibers and theexcellent spatial mode characteristics, fiber yellow lasers are preferredcandidates for various applications such as modern medicine, material
processing, high-resolution spectroscopy, military applications andlaser guide stars (LGS). Especially in the field of LGS, a 589 nm fiber
laser with high beam quality and narrow bandwidth (better than 50 MHz)is the key instrument for the astronomical adaptive optics systems. So,in past years, fiber based 589 nm sources have been actively studied.
So far, the mainly used methods to obtain 589 nm fiber lasers aredouble frequency of 1178 nm fiber lasers. Yb-doped silica fiber canlase at 1178 nm, but the gain is poor. Comparably, stimulated Raman
scattering (SRS) can convert 1120 nm pump laser to 1178 nm withmuch higher efficiency. So, in the paper, we experimentally demonstrate
a 976 nm LD pumped 1120 nm Yb-doped fiber laser, which will
be subsequently used to obtain 1178 nm signal laser in the SRS
experiment. The resonator composes a normal single-mode Yb-doped
fiber and a pair of fiber Bragg gratings (FBG). The FBG1 is the totalreflection mirror with a reflectivity above 99%. The FBG2 is the output
coupler mirror with a reflectivity of about 10%. The maximum output
power of 1.5 mW is achieved. The central wavelength is 1119.95 nmwith a linewidth of 0.2 nm. To realize 1178 nm lasing in the Raman fiber,
the output power of the 1120 nm fiber laser must be scaled to a muchhigher level and this can be realized by applying high power pumping
and using double-clad Yb-doped fiber in the subsequent experiments.

8555-53, Poster Session

Add-drop filters based on asymmetric highorder microring resonators

Hybrid integration of III-V RCE photodetector
with CMOS receiver on silicon platform from
Associated National Laboratory

Dong Zhang, Yongqing Huang, Xiaomin Ren, Xiaofeng Duan,
Bing Shen, Qi Wang, Xia Zhang, Shiwei Cai, Beijing Univ. ofPosts and Telecommunications (China)

Luo Yang, Yongqing Huang, Xiaofeng Duan, Xiaomin Ren,
Qi Wang, Xia Zhang, Shiwei Cai, Beijing Univ. of Posts andTelecommunications (China)

Add-drop filters are key components of Wavelength Division
Multiplexing (WDM) communication systems.

In recent years, the combination of III-V semiconductor devices with
Si manufacture techniques to develop optoelectronic integrated
circuits(OEICs) has been widely studied. In this paper ,the fabrication
procedure of a hybrid integration of monolithic InP-base resonant cavity
enhanced (RCE) photodetector with silicon CMOS circuits is described.
To realize a low-loss , high-data-rate optoelectronic micro system sothat create an integration optoelectronic/electronic device is necessary. optoelectronic active devices and processing circuits is attractive
in a packaging on a platform. For this project , RCE photodetector isdesigned using P-I-N diodes with a InP/ln0.67Ga0.33As0.7P0.3 layers
structure with high reflectivity InP/Air gap distributed Bragg reflectors(DBRs). It has a high quantum efficiency of 59% at 1550nm wavelenght,
the dark current of 2nA at 3V reverse bias, the 3dB bandwidth of nearly
8GHz have been achieved. The processing circuits using a low-cost
standard industry CMOS process chip.The monolithic photoelectronic
detector and a transimpedance amplifier(TIA) chip are bonded on a
Si substrate platform via metal wafer bonding technology. Becauseof the InP-based photoelectric detector(PD) and CMOS process chip
are quite sensitive to temperature and stress-induced degradation, So
the bonding metal should be chosen to have high thermal conductivity
and stress-relief. We chose Au-Sn20 as the bonding media for large
number of experiments. Si substrate not only provide a platform
to place devices on it ,but also can as a heat sink for it has a goodthermal conductivity. After TO-CAN packaging we test the whole

Our effort is devoted to a wide free spectral range (FSR) and a flat-top
response with a sharp roll-off from passband to stopband. FSR is a key
parameter for Add-drop filters, an appropriately FSR should operate
within the entire C-band (1530-1562nm). Flatness of the passband andsharp roll-off from passband to stopband are necessary to minimize thepulse broadening.
There are two custom ways to extend FSR. Firstly, the direct way
to increase the FSR of a microring resonator is to reduce its radius.
However, decreasing the bending radius of an optical waveguide
will increase dramatically the bending loss. Secondly, a widely usedalternative to extend FSR is Vernier approach, where microrings ofdifferent diameters are used to obtain 6-50 fold increase of the FSRof the single resonators. Although Vernier effect is effective in seriescoupled ring resonators, spurious interstitial mode may increase when
FSR expansion fold is large.
In this paper, an asymmetric high-order microring filter is proposed,
the aim is to achieve large extension ratios and adequate suppressionof the spurious interstitial mode, meanwhile, a flat-top and steep-side
response of filter could be obtained by this approach. Our simulation
results showed an extended FSR of 40nm, which can operate within
the entire C-band, enlarging the interstitial peak suppression from 5dB

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hybrid integration device on a optical test PCB. A clear transmittereye diagrams is measured for the total integration device of frequency
response.

8555-56, Poster Session

8555-54, Poster Session

Hui Wang, Beijing Univ. of Posts and Telecommunications(China); Qi Wang, Beijing Unv. of Posts and Telecommunications(China); Zhi-Gang Jia, Ying-Ce Yan, Yong-Qing Huang, Xiao-Min
Ren, Beijing Univ. of Posts and Telecommunications (China)

Hermite Gaussian approximation for TE1
mode of dielectric planar waveguide
Ziyun Wang, Lianhuang Li, Fuyuan Guo, Fujian Normal Univ.
(China)Because the Gaussian beam theory is perfect, the Gaussian
approximation is used to express some light beam frequently.The
normalized frequency is one of the most important parameters of
optical waveguide, then, the relation between M^2 factor and thenormalized frequency of TE1 mode of dielectric planar waveguide ispresented when the half width of core layer is given, the minimum
value of M^2 factor is 3.049 and M^2 factor tends to 3.403 when thenormalized frequency tends to infinity. As the M^2 factor of TE1 modeof dielectric planar waveguide is close to 3 in the proper rang and theM^2 factor of the first order Hermite Gaussian beam is 3, the first order
Hermite Gaussian approximation for TE1 mode of dielectric planar
waveguide is reasonable.
The radius of the beam of the first order Hermite Gaussian
approximation is expressed by equivalent mode field half width whichis the geometrical mean of the mode field half widths defined bysecond order moment and differential operator. The matching efficiency
between TE1 mode of dielectric planar waveguide and the first order
Hermite Gaussian beam is good.
A simple fitting expression of M^2 factor and equivalent mode field half
width is suggested, the numerical calculation indicates that the maximal
relative error of M^2 factor and equivalent mode field half width is lessthan 2 percent in the proper rang.

8555-55, Poster Session

Analysis and design of a tunable filtering
waveguide based on silicon-on-insulator
Fuquan Hu, Yongqing Huang, Xiaofeng Duan, Xu Zhang, Xinye
Fan, Xiaomin Ren, Qi Wang, Xia Zhang, Shiwei Cai, Jinhua Hu,
Beijing Univ. of Posts and Telecommunications (China)
One of the current research trends in silicon photonics is to integratemany kinds of optical functionalities on a single chip, which can leadto superior or novel functionalities. In this paper, based on Silicon-onInsulator (SOI) we design a tunable filtering waveguide consisted of a
Fabry-Pérot filtering-cavity and a straight waveguide. The Fabry-Pérot
filtering-cavity is used for wavelength selectivity and the waveguideis used for light guide, which can be fabricated by utilizing electron
beam lithography and inductively-coupled-plasma reactive ion etching(ICP-RIE) technique. The transmission characteristic of the device
has been numerically simulated. The result shows that the Full-Width
Half-Maximum (FWHM) is inversely proportional to pairs of the DBR.
The FWHM decreases as the increase of the pairs of DBR. The peakwavelength is changed by changing the refractive index of DBR or
the cavity of the Fabry-Pérot filtering-cavity. In order to tune peakwavelength, we can deposit different materials in the air grooves tochange the refractive index of DBR or change the current to change
the temperature of the cavity, so the length of cavity can be altered.
The result shows that the peak wavelength changed 2 nm whenchanging the length of cavity by 3 nm. The tunable filtering waveguidecan be integrated with waveguide photodetector, and the integrated
photodetector will show great importance for the realization of
optoelectronic integration circuits, hopeful to be widely used in WDM
system.

The influence of growth parameters on theformation on InAs/GaAs by MOCVD

InAs/GaAs quantum dots (QDs) have been grown by Metal-Organic
Chemical Vapour Deposition (MOCVD) in the Stranski-Krastanow
growth mode. We have investigated the influences of growthparameters such as the V/III ratio, growth temperature, QDs deposition
thickness and the deposition rate of the overgrowth layer to the QDs
qualities. Through the room temperature photoluminescence (PL)spectra, we have obtained the characters of QDs. The growth of
QDs is very sensitive to the growth parameters which influence theQDs quality nonlinearly. During our work , a narrowest FWHM but the
shortest center wavelength was obtained at the point of 25, when the V/
III ratio was increased from 12.5 to 31.25. A redshift in the PL spectra
and a broaden FWHM was obtain when the growth temperature wasincreased from 480°C to 520°C. A narrowest FWHM but a shortest
center wavelength was obtained at the point of 3.0ML when thedeposition thickness of QDs was increased from 2.7ML to 3.3ML.
Overgrowth layer was grown with the deposition speeds of 0.1ML/s and
0.08ML/s , the latter brought a narrower FWHM. In an extensive studyof the growth parameters, InAs/GaAs QDs with 80 mev of FWHM at
1.12µm were achieved.

8555-57, Poster Session

Coplanar lumped electroabsorption
modulator fabricated on the common n-type
InP substrate
Can Zhang, Song Liang, Li Ma, Baojun Wang, Hongliang Zhu,
Wei Wang, Institute of Semiconductors (China)
A coplanar lumped electroabsorption modulator (Co-LEAM) based onn-type InP substrate is designed and fabricated, which is convenient tointegrate and package with the flip-chip bonding technique. The deviceshows a high VBR nearly -25 v. The device capacitance is 0.55pf withthe back n-electrode and 0.62pf with the coplanar n-electrode, which
could satisfy a 10Gb/s bandwidth. The characteristic of extinction ratio
is compared with the common LEAM.

8555-58, Poster Session

A polymer-modified PbS quantum dot fiber
amplifier excited by evanescent wave
Xiaolan Sun, Libin Xie, Wei Zhou, Shanghai Univ. (China)
A novel polymer-modified PbS quantum dot (QD) optical fiber amplifier
was proposed and demonstrated. Fabricated by depositing the PbS
QD doped film around the tapered single mode fiber (SMF) coupler, theamplifier can produce a significant gain within the wavelength range
between 1450 and 1650 nm by evanescent wave excitation. The PbS
QDs were synthesized in an organic phase - by which we can acquire
QDs with high quantum yield. Then QDs were transferred into waterby polymer modification. Amphiphilic polymers modification will notaffect the surface ligands and thus the initial high quantum yield can beretained. Also we can lower the refractive index of film (lower than therefractive index in fiber cladding material) to ensure the confinementof light wave. PbS QD doped film was achieved by mixing PbS QD
solution and SiO2 sol-gel solution. The tapered SMF coupler was
fabricated by flame fused taper technique using standard SMF. The
tapered region length was about 2 cm, and the waist diameter was
about 12 um. The mixed solution after ultrasound treatment was coated

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Conference 8555:
Optoelectronic Devices and Integration IV
onto the tapered region of fiber coupler and aged for 3 days at room
temperature to obtain an amplifier. The signal produced by 1550 nm
semiconductor light emitting diode can be amplified by the PbS QD
optical fiber amplifier. With increasing pump (a 980 nm laser) power, thegain increases from 2 dB to about 6 dB gradually.

8555-61, Poster Session

8555-59, Poster Session

Kang Li, Shanghai Univ. (China); Fufei Pang, Xiaobei Zhang,
Tingyun Wang, Shanghai Univ (China)

A flat-top steep-edge waveguide
photodetector composed of cascaded
silicon microring resonators
Jinhua Hu, Yongqing Huang, Xiaofeng Duan, Xinye Fan, Fuquan
Hu, Bing Shen, Luo Yang, Qi Wang, Xia Zhang, Xiaomin Ren,
Beijing Univ. of Posts and Telecommunications (China)
Optical photodetector with filtering function is one of key elements in
Wavelength Division Multiplex (WDM) optical communication system.
Microring resonators using silicon-on-insulator waveguide are highly
promising for photonics integrated technology due to the excellent
filtering functions and the compatibility with complementary-metaloxide-semiconductor (CMOS) processes. In order to enhance thetolerance of signal wavelength drifting in optical communication
system, we proposed a novel photodetector with flat-top steep-edge
response, composed of cascaded microring resonators on siliconon-insulator in this paper. In the photodetector, we used polarization
insensitive cascaded silicon microring resonators as optical filter cavity,and used a silicon racetrack resonator bonded in p-i-n chip as opticaldetecting cavity. We used finite element (FE) mode solver, finite different
time domain(FDTD),and transfer matrix method (TMM) to simulate thebehavior of the polarization insensitive optical filter. With optimized
parameters, the photodetector showed high quantum efficiency,
narrow line width and flat-top steep-edge. Comparing with traditional
photodetector, this device had more compact and higher integrated
level. This photodetector is very suitable for Wavelength Division
Multiplex communication system.

8555-60, Poster Session

The tunable demodulator of DPSK based onreflection differential delay interference
Guodong Liu, Chongqing Wu, Yaya Mao, Zhengyong Li, Beijing
Jiaotong Univ. (China)
A new scheme of demodulating DPSK signal is proposed based on
structure of differential delay interference which is suitable for variable
bit-rate and the tuning speed is faster than the existed demodulator.
The experimental setup is composed of a circulator, collimator anda total reflecting mirror. The part of light beam incident to collimatorreflects on its end as referring beam; the other transmits to the totalreflecting mirror and reflecting back to the collimator as detecting
beam. Referring beam and detecting beam interfere in the detector.
In order to get the best results of interference, according to analysis
and measurement, we make the reflectivity of the end of collimator is40%, the transmittance of collimator is 60%, and the transmittanceof reflecting mirror is 100%, so when the detecting beam return tothe collimator, the reflecting beam and detecting beam have theequal amplitude. Adjusting the distance between the collimator andthe total reflecting mirror by electric translation stage equals to halfof transmission length of one bit signal in the air, referring beam anddetecting beam carry phases of the adjacent symbols respectively,
so the adjacent symbols interfere and then are demodulated. The
demodulation of variable bit-rate NRZ-DPSK formats of 10Gb/s and40Gb/s are demonstrated, the BER after demodulating is lower than
10-9. The demodulation results of 10Gb/s and 40Gb/s DPSK signal arealso compared, it shows that the demodulation system is stable.

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Design and fabrication of the Y-branchwaveguide for optical printed circuitboard(OPCB) interconnect

With the rapid development of the fiber-optic communication
technologies, the interconnect system is becoming more and more
complex. Traditional electrical interconnect technologies on printed
circuit board (PCB) are facing big challenges due to the limitation of
bandwidth and data transmission rate and can not meet people’s
increasing requirements. In recent years, the interconnect technologyof the optical printed circuit boards (OPCB) has become more andmore mature. Compared with the traditional electrical interconnect
technologies, the OPCB technology has the advantages of high data
rates, wide bandwidth, low loss and low crosstalk. In this paper, a
low loss multimode Y-branch interconnect optical waveguide wasdesigned and fabricated. The transmitting properties of the Y-branch
splitter were designed and simulated by using a commercial waveguidesimulation software. For a 1 x 2 Y-branch splitter with 50µm x 50µm
channel waveguide, the relationship between insertion loss and splitting
angle was calculated. The splitting angle was optimized to realize acompact size of the Y-branch splitter. According to the theoreticalresult, a multimode Y-branch waveguide was fabricated based on a UVlithography method on the printed circuit board. To balance the tradeoff between the insertion loss and the component size, the Y-branchwaveguide was designed of two sections with different splitting
angles. An insertion loss of 0.36dB was observed with a 5cm Y-branchwaveguide. Based on the low loss and compact size, the multimodeY-shape interconnect optical waveguides will find a wide application in
future optical communication interconnect system.

8555-62, Poster Session

High stable single-polarization tunable fiber
laser based on Opto-DMD processor andpolarization-maintaining fiber devices
Huang Kuizhi, Yan Binbin, Beijing Univ. of Posts andTelecommunications (China); Xiao Chen, Genxiang Chen, Ai Qi,
Minzu Univ. of China (China); Wang Kuiru, Beijing Univ. of Posts
and Telecommunications (China); Yiquan Wang, Ying Zhang,
Minzu Univ. of China (China); Feijun Song, China DahengGroup, Inc. (China); Sang Xinzhu, Beijing Univ. of Posts andTelecommunications (China)
Tunable fiber laser with narrow line-width operation and uniform
amplitude output has attracted a lot of research interests because of
its potential applications in optical communications, optical instrument
testing and optical fiber sensors. A high stable wavelength-tunable fiber
laser is experimentally demonstrated by using a digital-micromirrordevice (DMD) processor and a polarization-maintaining erbium-doped
fiber amplifier (EDFA).The electronic-addressed DMD processor is able
to select and couple a waveband from of the polarization-maintaining
EDFA back into the fiber ring to generate a narrow line-width laser
output. The tunable fiber laser shows a line-width of 0.02nm, a tuning
step of 0.08nm over the c-band and a side mode suppression ratio(SMSR) greater than 50 dB. The output power uniformity of 0.01mw
is achieved by using the automatic power control (APC) system underroom temperature. The center wavelength fluctuation during 1 hour isbelow 0.02 nm.

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8555-63, Poster Session

A photonic instantaneous microwave
frequency measurement without ambiguities
Nuannuan Shi, Xiuyou Han, Yiying Gu, Meng Wang, Jingjing Hu,
Mingshan Zhao, Dalian Univ. of Technology (China)
Attention has been turned to the approach of photonic microwave
frequency measurement with the advantage of large bandwidth, lowpower consumption, light weight and immunity to electromagnetic
interference. Comparing with the traditional electronic methods,
photonic approach can realize wide detection bandwidth and real-time
operation which has great importance for unknown interceptive signal.
For both military and civil applications, it is often required that the radarsystem has the capability of measuring the frequency of an unknown
electromagnetic signal over a large spectral range.
In this paper, a novel technique for instantaneous frequency
measurement of unknown microwave frequency based on the phasemodulation and intensity modulation is theoretically and experimentallydemonstrated. And the experimental results are presented with themeasurement error smaller than 200MHz. In the proposed system, twodifferent wavelengths of light are respectively for the phase modulationand the intensity modulation. These two modulated optical signals
propagate in two segments of single-mode fibers. The electrical power
after photodetection is related to laser power, laser wavelength, fiber
dispersion, modulation index and microwave frequency. The above
parameters are optimized in order to reduce measurement errors.
Based on the output microwave power, three amplitude comparison
functions (ACFs) are established to realize frequency measurement
ranged from 1GHz to 20GHz. The unknown frequency is measured in
the large slope of ACFs. At the same time, three ACFs are combined
to realize the unambiguous determination of the microwave signal
frequency beyond a single monotonic region of the ACF. Further
research is being conducted and the results will be presented in the
coming conference.

8555-64, Poster Session

Temperature tuning of the resonant photonic
band gap of InAsP/InP Bragg-spaced
quantum wells grown by MOCVD

provide extra design freedom to tailor the dispersion while keeping alarge fraction of the guided mode in a nanometer-wide slot. Here wetheoretically investigate the dispersion of the engineered FSWs. Our
results show that low dispersion of ± 10 ps/(nm•km) over a 340 nm
wavelength range can be realized. It presents great potentials in fiber
micro-devices for high-speed optical communications.

8555-66, Poster Session

Micro-cavity lasers with highly directionalemission
Changling Yan, Changchun Univ. of Science and Technology(China)Micro-cavity lasers have attracted a lot of attention due to their low
threshold high cavity Q factor and being suitable for high density
optoelectronic integration. Optical micro-cavities which can confine
light in a small mode volume with high quality factors have become an
important platform not only for optoelectronic applications with densely
integrated optical components but also for fundamental studies suchas cavity quantum electrodynamics and nonlinear optical processes.
Micro-cavity lasers have low threshold current densities but their
optical power output is very low due to total internal reflection of thewhispering gallery modes WGMs and their far-field profiles are isotropic.
To overcome the intrinsic problems of microdisk lasers, several typesof deformed structures were proposed, which are typically stadiumshaped lasers, bow-tie mode lasers, and spiral-shaped lasers, and thetriangle cavity structures have also been reported. Recently, a limaçonshaped microcavity has been proposed as a promising resonator shapefor microcavity lasers with attractive properties such as a directionalemission and a high cavity Q-factor. In this paper we compared several
kinds of micro-cavity quantum cascade lasers with the limason shapecavity, the triangle shape cavity and ellipse shape cavity upon their farfield patterns. Quantum cascade lasers (QCLs) are especially suited forthe micro-disk geometry due to their lack of surface recombination andinherently in-plane, transverse magnetic (TM) mode emission. Finallyby using quantum cascade lasers material, InP based InGaAs/InAlAs
quantum cascade structure with about 10um emitting wavelength, thethree kinds of micro cavity lasers are compared about output emission
characteristics such as the far-field patterns, threshold current and light
output power.

Wei Yan, Wuhan National Lab. for Optoelectronics (China)

8555-67, Poster Session

In this article, we presented a study of InAs0.04P0.96/InP Braggspaced quantum wells (BSQWs), a type of resonant photonic band
gap structure (RPBG), grown by metal organic chemical vapor
deposition (MOCVD). The quantum wells were characterized byphotoluminescence (PL), double-crystal x-ray diffraction (DC-XRD), andreflection spectra. We found that the BSQWs structure grown at 580°C
appears to be extremely abrupt, uniform, free of misfit dislocations, andnarrow PL line width. By researching the reflection spectra at different
temperature, we presented a theoretical analysis of the changes in
RPBG, and proposed a new scheme of using the temperature to control
the resonant photonic band gap structure.

Long distance optical printed circuit board
for 10Gbps optical interconnection

8555-65, Poster Session

Wideband nearly-zero dispersion in fiberized
slot waveguides
Qi Liu, Nanjing Univ. (China)
The dispersion of circular microfiber (CMF) can be reduced or evenmade anomalous at visible and near-infrared wavelengths. However, it
is still a difficult task to achieve dispersion flattening. Combining current
mature technology of drawing CMFs and micro-machining, it is possibly
easier to realize a so-called fiberized slot waveguide (FSW), a microfiberwith a slot inside. Same as the air-hole in PCF, a slotted structure could

Shiqiong Chen, Fufei Pang, Kang Li, Shanghai Univ. (China);
Jinhua Wu, TTM Technologies, Inc. (China); Marika P. R.
Immonen, TTM Technologies, Inc. (Finland); Xiaobei Zhang,
Shanghai Univ. (China); Tingyun Wang, Shanghai Univ (China)
Optical printed circuit boards (OPCB) are a very important techniqueto realize wide band and high speed interconnection between board
to board. With rapid increase of capacity in fiber-optic communication
system, the layout of OPCB becomes more and more complex, which
will increase the size of OPCB largely. Therefore, to realize hightransmission-rate interconnects on a long distance, OPCB technique
has become an important trend. In this paper, a long-distance OPCB
was fabricated to realize high-speed optical interconnects. The OPCB
was made up of polymer optical waveguide fabricated by using an
ultraviolet (UV) photolithography technique. The length of OPCB is30cm long. The minimal transmission loss of the polymer opticalwaveguide is approximate 5.36dB at 850nm wavelength. Two MT-RJ
optical connecters were assembled on the OPCB to realize optical
coupling between optical fibers and waveguides. The dependence of
coupling loss on misalignment was obtained with different offset value
theoretically and experimentally. The minimal total insertion loss is only
8.06dB. With 10 gigabits-per-second (Gbps) optical transceivers as the79A  
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input/output module, we connected the polymer waveguide with opticalfiber by MT-RJ connecter and tested the performance of the OPCB. The
date rate of 10Gbps can be transmitted successfully. Additionally, therelationship between the packet loss rate and total loss is also studied.
It is found out that when total loss is less than 10.5dB, the whole data
which is sent can be received.

8555-68, Poster Session

Negative feedback optical amplification
effect based on optical triode
Yuma Fujikawa, Mohamad Syafiq Azmi, Yoshinobu Maeda,
Kinki Univ. (Japan)
We demonstrated noise suppression characteristics of negative
feedback optical amplifier using an optical triode. The optical triodethat constituted by two semiconductor optical amplifiers (SOA) is basedon change of gain in a SOA by cross-gain modulation (XGM). In thisexperiment, input signal light of 10 Gbps modulated NRZ signal withwavelength 1551 nm is used. The input signal light is divided into two
by a coupler. One is fed to the first SOA and is used for generating an
inverted signal light by XGM. The other and the inverted signal light are
fed to the second SOA at the same time. The signal light is amplified
with the gain modulation which depends on the inverted signal light.
In order to evaluate the effect of gain modulation we measured a
relationship of the inverted signal light intensity and bit error rate.
Consequently, as the intensity of inverted signal light was increased,
the received sensitivity was better. As compared with no inverted
signal light, the received sensitivity was improved more than 4 dB. The
negative feedback optical amplification effect based on gain modulation
improves a extension ratio and a overshoot of output signal.

8555-69, Poster Session

Simulation and parameters optimizationof high gain silicon micro-pixel avalanche
photodiode
Fangkui Sun, Huaiqi Gu, Lixue Chen, Zhiwei Wang, Harbin
Institute of Technology (China)

8555-70, Poster Session

Blue-green reflection-mode GaAlAs
photocathodes
Xinlong Chen, Jing Zhao, Benkang Chang, Muchun Jin,
Guanghui Hao, Yuan Xu, Nanjing Univ. of Science andTechnology (China)
The traditional negative electron affinity GaAs photocathodes havethe wide spectral response, which ranges from 400 nm to 1000 nm.
The GaAs photocathodes are widely used in the area of night vision,
but not applicable for the field of ocean exploration because theseawater is a good window to blue-green light. In order to obtain thesuitable photocathode, the p-type zinc (Zn)-doped reflection-mode
GaAlAs photocathode samples using exponential-doping technique aregrown by metal organic chemical vapor deposition, the Al componentof GaAlAs emission layer is designed to be 0.63. After the chemicalcleaning, the photocathode samples are heated in vacuum at hightemperature of 650°C and 600°C respectively, the vacuum variation
curves during the heat cleaning are measured, which correspondto the desorption of oxides in the surface of GaAlAs emission layer.
The (Cs, O) activation for the photocathodes is executed after heatcleaning. Different proportion of Cs and O is performed on the different
photocathode samples. The active photocurrent curves of two samples
with different heat-cleaning temperature show that the GaAlAs surface
treated by higher heat-cleaning temperature is more sensitive to theCs-O adsorption. The photocathode activated with the larger Cscurrent has a shorter time to reach the first photocurrent peak, andalso obtains a bigger final photocurrent peak. The spectral response
curves are measured by the on-line spectral response measurement
systems after activation. According to the measured spectral response
curves, it could be found that a suitable heat-cleaning temperature
and a moderate Cs/O current ratio are very important to prepare highperformance GaAlAs photocathode. The prepared reflection-mode
GaAlAs photocathodes are response to the blue-green light, and thecut-off wavelength is at about 580 nm.

8555-71, Poster Session

Beam steering based on multi-waveguide
shifter

Avalanche photodiode (APD) is an attractive candidate for the
replacement of photomultiplier in photon counting, and it has also
been used in many photoelectric detect field include ladar, bioaerosol detection, fiber communication, and low-light imaging. It canbe compact, provides high internal gain. In addition, compared withother direct band gap materials, Si material has much lower inter-bandtunneling current, which makes a better noise performance of Si-APD.
The internal photocurrent amplification in APD is based on avalanche
multiplication process. To get higher gain, the device is often to workin or above the breakdown voltage. With the increasing requirement of
APD array integration, the study of high-gain and low operating voltage
for APD pixel has become an urgent requirement. The appearanceof micro-pixel APD sizes under 100µm provides a way to solve thisproblem. A compact array which meets the requirements could be theduplication of hundreds micro pixels.

Dengcai Yang, Dayong Wang, Zhiyong Wang, Beijing Univ. ofTechnology (China)

In this paper, the silicon avalanche photodiode (Si-APD) size in micron,which was comprised of separate layer of absorption charge andmultiplication(SACM) has been studied. The influence of different
thicknesses and different doping concentration of the absorption,
charge and multiplication layer on the electric field distribution, currentvoltage characteristic and breakdown voltage were simulated andanalyzed respectively. The structural parameters optimization has bedone with the simulation results. The results show that the better gain
and low bias voltage can be achieved with layer thicknesses in micro/
nano-sized, which can give a high gain of 106 and low bias voltage of
127V. Also the fabrication process conditions has been given.

Recent years, several approaches have been provided to achieve phaseshift, such as waveguide, grating, PZT, liquid crystal. Each way has
advantage and shortcoming. As some researchers had great progressof the fiber laser and integrated optics in recent years. because thewaveguide for phase shift has some advantages, including impact, easy for integration, it is an inevitable trend for all-optical to use
waveguide for phase shift in the PLA, In this paper, a multi-waveguidebased Lithium Niobate(LiNBO3) is provided. And the multi-waveguideis processed by proton exchange. The phase is shifted by loading thevoltage on the electrode crossing the waveguide. In this experiment,
a DFB source and four channels waveguide are used. The beamcombination unit is one dimension. And the combination beam is
detected by CCD. From the experiment, The combination beam scan

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Laser- phased -array(LPA) system has attracted more and more
researchers because of its excellent performance. Including achieving
high-resolution ; rapid; flexible beam steering. So it may be used many
fileds in future such as laser display,laser radar,and high power laser
process.
In a LPA system , the performance is mostly decided by three factors,
the firs is the coherence source array. A perfect coherence sources
are needed to achieve high performance combination beam. And thesecond is the phase control unit, which ensure the beam scanning
accuracy and the beam quality. the last is the beam combination unit,
which still ensure the far field beam quality. In this paper, an approachof the phase control is discussed theoretically and experimentally.

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with the variation of the voltage. It achieve the beam steering. And thesteering angle reach to ±3°8555-72, Poster Session

Direct-detection WiMax orthogonalfrequency division multiplexing over fiber
access networks
Jing He, Hunan Univ. (China); Jinshu Su, National Univ. of
Defense Technology (China); Yuan Huang, Hao Liu, Hunan Univ.
(China)The future access networks should provide high bandwidth, improved
network flexibility, mobility and cost-effective access. Recently
broadband wireless access technology such as WiMax for Wireless
Metropolitan Area Networks has become a strong candidate for thelast mile wireless connectivity to provide flexible broadband services
to end users. According to WiMax standard, the typical cell coveragecan extend to 5 km in the atmosphere, with selectable channel
bandwidth. However, the WiMax signal distribution would be greatly
hindered as signal access inside a long tunnel and indoor. There is areal desire to merge the wireless and optical wire network into a single
infrastructure. Previous investigation reported that using radio-overfiber (RoF) technology to carry the WiMax signal and investigated theperformance of WiMax RoF system such as throughput and packet-loss
at different link lengths. The transmission limitation and performance ofthe standard WiMax access in RoF link is demonstrated, but it focus on
standard mobile WiMax for the applications in the high speed railway.
In the paper, we have demonstrated novel optical-wireless architecture
consists of a wireless network and an optical network, and applied
IEEE 802.16 standard WiMax OFDM modulation to the optical-wirelessarchitecture by simulation. Based on the constellation diagrams of thereceived signal and the measured error vector magnitude after direct
detection, simulation results show that the proposed system cansuccessfully transmit a high capacity WiMax OFDM signal over 250km
SMF without any amplification, which can extend the network converge
distance of optical network and serve more end-users who share an
optical line terminal link.

Wei Wang, Institute of Semiconductors (China)
The device was fabricated on n-type InP substrate. Strained multiple
quantum-well (MQW) material was designed and grown using
metal organic chemical vapor deposition (MOCVD). The divice iscomposed with phase section, grating section and gain section.
Photoluminescence spectrum peak of the grating section’s material wasblue shifted by Quantum-well interference (QWI) method.
The device was characterized. Single mode stability and wide tuning
range make the device suitable to be used for trace-gas sensing withthe technique called Tunalbe Diode Laser Absorption Spectroscopy(TDLAS). The special wavelength was design for CH4 trace-gas
sensing.

8555-75, Poster Session

Saturable absorption in graphene at 800 nm
band
Shunbin Lu, Shuqing Chen, Zhiwei Zheng, Han Zhang, Chujun
Zhao, Shuangchun Wen, Hunan Univ. (China)
Graphene exhibits broadband optical saturable absorption due to
its linear energy band structure and the Pauli blocking principle. We
experimentally demonstrated the saturable absorption in graphene
at 800 nm. The graphene sample under investigation, which consistsof three layers grown by chemical vapor deposition (CVD) method,
is transferred from the copper substrate to the quartz substrate.
Two-dimensional Raman mapping shows its high material quality.
By performing the balanced twin-detector measurement technology,
we are able to characterize the nonlinear optics property of the asfabricated graphene sample. The incident laser source is based on a
Ti: sapphire femoto-second laser with a central wavelength of 800 nm,
a repetition rate of 1 kHz and a pulse duration of 100 fs. Under strong
illumination, we find that the absorption of graphene decreases with
the increase of incident power, and by fitting the experimental data withtheoretical model, the saturable intensity and the normalized modulation
depth are measured to be 7.911 GW/cm2 and 10.6%, respectively. The
experimental results show that graphene may be a promising saturable
absorber, with the potential laser photonics applications such as lasermode locker or Q-switcher, at 800nm band.

8555-73, Poster Session

Optimized parallel energy storage anddelivery solar lighting and heating system
Junewen Chen, Chung-Hua Univ. (Taiwan)
We have designed and efficiently developed a parallel energy storage
and delivery solar lighting and heating hot water system. The complete
system is designed and simulated with practical data to evaluate andoptimize the efficiency. A well fabricated solar energy system had beenin operation and had achieved best efficiency compares to the othertraditional systems. The optimized compulsive circulate controls of thesolar heater were investigated in detail. Based on the thermodynamic
theories of the solar heating and the solar source various incident
angles, we have design a control circuitry that can automatically control
as well as maximize the overall efficiency. Our designs also embeddedin the system monitoring and protecting capabilities. The integrated
system control loop design can accordingly switch the system to havemaximum efficiencies. This design results also gave high commercial
value.

8555-74, Poster Session

1.65um distributed Bragg reflective (DBR)
laser for CH4 trace-gas sensing
Bin Niu, Hongyan Yu, Liqiang Yu, Jiaoqing Pan, Lingjuan Zhao,

8555-76, Poster Session

Model of a series-cascaded fractal
topological structure of microring resonatorarraysXiaobei Zhang, Yingchun Li, Fan Gu, Biyun Jin, Shanghai Univ.
(China)A series-cascaded fractal topological structure of microring arrays
is proposed, by introducing fractal topological structures to all-pass
microrings. Every unit of this series-cascaded fractal topologicalstructure regard as a series-cascaded microring, thus these units form a
special microring arrays by series-cascaded method. Due to resonanceoccurring in every unit and the whole region of the series-cascaded
fractal topological structure, the performance of transmission spectraand delays are improved significantly. Its analytical model is establishedby the transfer matrix method. Then the characteristics of this structure
are investigated by the effects of coupling coefficients and loss.
Generally, there are dips with the resonator number in the transmission
spectra. As the loss increases, the average intensity decreases.
However, the delay becomes interesting positive and negative delays.
As the ring-bus coupling coefficient decreases, the dips of thespectrum become degenerated. However, there are several delay peaks
with some positive and other negative delays. These kinds of multiple
positive and negative delays can be explored for applications in alloptical delay lines.

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Conference 8555:
Optoelectronic Devices and Integration IV

8555-77, Poster Session

8555-25, Session 6

Temperature tunability of hybrid material
infiltrated photonic crystal fiber

Rigorous calculation of optical modes andtheir interference induced power distribution
in arbitrary numbered coupled slab
waveguides (Invited Paper)

Yinping Miao, Nankai Univ. (China)
The advent of photonic crystal fibers (PCFs) offers an excellent
carrier for the further development of novel functional materials.
PCFs, possessing several distinguished characteristics comparedwith conventional single-mode fibers, have attracted a lot of researchinterest. It is a special kind of optical fibers with micrometer-sized airholes running along the length of the fiber axis. Infiltration of advanced
materials into the air holes of the PCFs would effectively combine theirunique optical properties with material features together efficiently andprovide opportunity to achieve tunable fibers and relevant photonic
devices.
in this paper, Fe3O4 nanoparticles were superficially modified byrefractive index liquid and then filled in the air-hole of photonic crystal
fibers, and based on this structure the temperature-dependent
properties of the fluid material and the infiltrated fiber have been
investigated. Experimental results show that there exists some selfassembly phenomenon that two-dimensional and grating-like fluid
structure form along the fiber axis. Three resonant peaks of the quasiLPG turn up in the wavelength range from 800nm to 1700nm. Basedon the enhanced negative thermo-optical effect of the infiltrated media,
the resonant peaks show blue-shift in different degrees as temperature
increases. The highest temperature sensitivity reaches 4.4nm/°C at
1610.4 nm, which is 440 times higher than that of conventional fiber
grating (~0.01nm/°C). It is possible to acquire composite magnetic
fluid with excellent optical property by selecting and optimizing thesurfactant of Fe3O4 nanoparticles. Through combining the channelsof PCF with advanced material, photonic devices have advantages ofcompact size, high sensitivity and stability, ease of fabrication, etc.

8555-78, Poster Session

Selective etching of metamorphic GaAs/Si
and InP/GaAs wafers
Xiong Zhen, Qi Wang, Zhigang Jia, Yingce Yan, Yongqing
Huang, Xiaomin Ren, Beijing Univ. of Posts andTelecommunications (China)
Heteroepitaxial growth of GaAs on Si and InP on GaAs plays a very
important role in promoting the optoelectronic integrated (OEIC)
technology. The threading dislocation density of GaAs/Si and InP/
GaAs heterostructures seriously influence the performance of devices.
Compared with transmission electron microscopy (TEM) which requires
arduous sample preparation, long cycle and high cost, selective
chemical etching methods have been widely used to reveal dislocations
due to its merits of intuitive results, low cost and simple experimental
procedure.
In this paper, GaAs/Si and InP/GaAs wafers growth was performed by
low-pressure metal-organic chemical vapor deposition (LP-MOCVD)
using a two-step growth method. The wet chemical etching methods
were used to characterize the dislocations density. For the GaAs/
Si wafer, the chemical etching was performed in molten KOH attemperatures about 350°C and for duration about 1.5min. For the InP/
GaAs wafer, the chemical etching was performed in H3PO4: HBr (2:1)
solution (Huber etchant) at temperatures about 20°C and for duration
about 2min.Then, the morphology of the dislocations characteristicsof the etch pit density (EPD) were examined with a high-resolution
field-effect scanning electron microscope (SEM). There are some
ellipse dislocations pits of the GaAs/Si wafer with a density about
2E7cm-2, and sizes ranging from 700nm to 1500nm in diameter, andthere are many sunken dislocations pits of the InP/GaAs wafer with adensity about 2E8cm-2, and sizes ranging from 300nm to 700nm indiameter. So the method has been accurate and convenient to show
the dislocations characteristics of metamorphic GaAs/Si and InP/GaAs
wafers.

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Guiru Gu, Xuejun Lu, Univ. of Massachusetts Lowell (UnitedStates)In this paper, we present a simple yet rigorous method based ontransmission matrix to calculate the optical modes and power
distribution in arbitrary numbered coupled slab waveguides. The opticalmode profiles and their refractive indices obtained by this method
are identical as those obtained from the BPM method. This method
doesn’t depend on the grid size and becomes much more efficientthan the BPM or CMT for a large number of coupled waveguides.
We also prove that the optical modes are orthogonal. Based on theorthogonal property, the coupling coefficients to the optical modes
and the interference of the modes are calculated along the wavguides.
We found that the optical power distribution among the waveguides
obtained by calculating the mode interference is very close to thatobtained by the BPM method, suggesting that the optical power
distribution among the waveguides as it travels along the waveguides isdue to the interference of the optical modes.

8555-26, Session 6

Error analysis and system implementation
for structured light stereo vision 3D
geometric detection in large scale condition
Li Qi, Xuping Zhang, Jiaqi Wang, Yixin Zhang, Shun Wang, Fan
Zhu, Nanjing Univ. (China)
Stereo vision based 3D metrology technique is an effective approachfor relatively large scale object’s 3D geometric detection. Unfortunately,with the object scale keep on increasing, it’s hard to maintain both
efficiency and high precision. In this paper, firstly we introduced thestructure and detection process of our structured light based stereo
vision detection system. The system used a 500mW line-structured
laser carried by a motor stage which set up in the middle of the twocameras. Secondly, we made an error analysis for large scale vision
detection based in the common parallel camera case. Based on thisanalysis we find out that the system precision is affected by various
factors such as the trigger time difference, the baseline length and thecommon field of view of the binocular system. After that, we proposedseveral system design principles in large scale vision metrology
applications. The prototype we built implements LVDS interface
embedded CMOS sensor and CAN bus to ensure synchronous trigger
and exposure. We tested the system in both indoor and outfield
experiments, the results of which demonstrate that the precision levelcan be guaranteed effectively.

8555-27, Session 6

Thermal effects on interconnect crosstalk of
optoelectronic transmitter modules
Ikechi A Ukaegbu, Bikash Nakarmi, KAIST (Korea, Republic of)
Optical interconnection technology have been widely studied as one of
the most potential technologies to meet the high speed requirementsof next generation computer systems. However, most optical andoptoelectronic components used in optical interconnection technology,
require electrical interconnects for power and signal transmission andthese electrical interconnects affect the performance optical link. As
clock frequency reaches the gigahertz band with signal transmission
rate reaching the gigabit range, signal reliability and performance are

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Optoelectronic Devices and Integration IV
determined by factors such as thermal effects.
Optoelectronic modules are sensitive to temperature changes which
has drastic effect on the performance of the modules and can affectthem by increasing crosstalk between channels; increasing thresholddensity which can lead to failure of device; decreasing output power oflaser; changing the wavelength of the emitted light; and broadening thespectral line width which affects the speed.
In order to investigate and analyze thermal effects on crosstalk andperformance of optoelectronic interconnects, two 4-channel transmittermodules have been designed and fabricated. The modules are a planar
and a multi-chip (MCM) transmitter module. The planar module uses theconventional wire-bonding for interconnect between the driver chip andthe VCSEL while the multichip module employs the flip-chip bonding
technology.
This work therefore presents an analytical model based on interconnect
parameters for thermal effects analysis on crosstalk of multi-channel
optoelectronic transmitter modules. The model is used to determine thethermal critical frequency, fcrit, above which signals become severely
deteriorated.

8555-28, Session 6

Monolithically integrated photodetector
with flat-top and steep-edge response forwavelength division multiplexing (WDM)
systems
Yongqing Huang, Xiaofeng Duan, Xinye Fan, Xiaomin Ren,
Qi Wang, Shiwei Cai, Xia Zhang, Beijing Univ. of Posts andTelecommunications (China)
The wavelength selective photodetectors are considered promising
candidates for application in high-speed optical communications andinterconnections, especially in wavelength-division-multiplexing (WDM)
optical communication. Some monolithically integrated wavelengthselective photodetectors have been realized, such as one-mirror
inclined three-mirror cavity (OMITMC) photodetector, multiple resonantcavities RCE photodetectors, photodetector arrays with multistep cavity
and so on. But many of these devices can’t get flat-top steep-edge
spectral response that is very important for using in WDM system. A
1550nm monolithically integrated photodetector with flat-top and steepedge spectral response is reported in this paper. The contradiction
among the quantum efficiency, high response speed and the narrowspectral response linewidth eacch other is overcome by the design ofa Si-based multi-cavity Fabry-Pérot (F-P) filter and a cone absorption
cavity. In the structure of this photodetector, there are five cavities
and six distributed Bragg reflectors (DBRs) for the narrow spectral
response linewidth and flat-top and steep-edge spectral response,
a cone absorption-cavity with an absorption enhancement effect forhigh quantum efficiency. Based on this structure, flat-top steep-edge
spectral response, high quantum efficiency, high response speed, and anarrow spectral response linewidth can be obtained simultaneously. The
In0.53Ga0.47As absorption layer thickness is 200nm. A peak quantum
efficiency of 55% at 1549.2 nm, the -0.5 dB band of 0.43 nm , the 25dB
band of 1.06 nm, and 3-dB frequency response bandwidth more than
16 GHz, are simultaneously achieved with the active area diameter of
30µm. The dark current as low as 10nA was obtained at a reverse biasof 3.0V in the device. Compared with other similar photodetectors,
this device has good flat-top and steep-edge response and ideal
high-speed characteristics can be applied to 100GHz channel spacing
DWDM system.

8555-29, Session 6

Polymer planar lightwave circuit based
hybrid-integrated coherent receiver foradvanced modulation signals
Jin Wang, Yang Han, Zhongcheng Liang, Yongjin Chen, Nanjing
Univ. of Posts and Telecommunications (China)
Advanced modulation formats have become attractive candidates
for optical transmission systems, because of their increased spectral
efficiency, improved dispersion tolerance, lower OSNR requirement androbustness towards nonlinear impairments. Applying coherent detection
technique to them makes it possible to electronically compensate
the signal impairments. A key issue for a successful deployment ofcoherent detection technique is the availability of cost-efficient andcompact integrated receivers. Such an integrated receiver is composedof an optical 90° hybrid and four photodiodes (PDs) that are betterto be integrated. Thus, a practical problem for a coherent receiver is
how to realize the optical 90° hybrid, which is cost-efficient and easily
integrated with PDs. In this work, three different types of optical hybrids
are fabricated with polymer planar lightwave circuit (PLC). Polymer PLC
technology is regarded attractive because it offers the potential of fairly
simple and low-cost fabrication, and of low-cost packaging. The first
type of realized optical hybrid is composed of four 3-dB couplers andan additional phase delay of 90° in one branch; the second type is touse a 2?4 MMI coupler; the third type is composed of one polarizationbeam splitter, which is realized by a polarization splitting thin film
element (TFE) , and two 3-dB couplers. Via 45° turning mirrors, thesethree optical hybrids are integrated with a PD-array, which comprises
four vertical backside illuminated PDs. Their performances, such as theinsertion loss, the transmission imbalance, the polarization dependence
and the phase deviation will be given. The realization challenges will be
discussed.

8555-30, Session 6

InGaN/GaN light-emitting diode on GaN/
Si template with AlN/GaN superlattice asinterlayer
Fang Ren Hu, Y. J. Wang, H. B. Zhu, Nanjing Univ. of Posts
and Telecommunications (China); M. Wakui, H. Sameshima, K.
Hane, Tohoku Univ. (Japan)
GaN on Si is attractive for the integration of light-emitting device andSi microelectronics. Also, highly functional and integrated optical
Micro-Electro-Mechnical-Systems (MEMS) can be developed, throughmonolithically integrating silicon three-dimensional structures andmicroactuators with nitride devices.However, the large differences oflattice constant and thermal expansion coefficient between GaN and
Si restrict high quality GaN crystal growth on Si. Lateral overgrowth,nanocolumn crystal and pattered substrate have proved to be effective
ways to grow GaN on Si. In our Riber32 molecular beam epitaxy (MBE)system, column crystal growth was deposited to improve the GaN
crystal quality. However, it is difficult to fabricate integrated devices
using GaN column crystal and Si. GaN/Si template is another effective
way to grow GaN on Si. Here we used the GaN/Si template as substrateand deposited InGaN/GaN p-i-n junction structure with AlN/GaN
superlattice layers as the interlayer. Different surface microstructure of
the p-GaN was affected by the amount of Mg flux. Light-emitting diodewas fabricated from the p-i-n junction. The crystal properties of InGaN/
GaN p-i-n junction and the related light-emitting diode properties were
investigated. The monolithical integration of GaN semiconductor and
Si Optical-MEMS would improve the application of GaN-based lightemitting devices in the Optical MEMS.

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Conference 8555:
Optoelectronic Devices and Integration IV

8555-31, Session 7

Surface-corrugated microfiber Bragg grating(Invited Paper)
Fei Xu, Jun-Long Kou, Nanjing Univ. (China); wei luo, nnajing
university (China); Yan-Qing Lu, Nanjing Univ. (China)
There are two steps to obtain as small as possible fiber Bragg gratings.
First, it is to taper the fiber and reduce its diameter. A subwavelengthscale microfiber (MF) is the basic element of miniature fiber devices
and sub-systems. Then it is to reduce the grating length. For shortfiber grating, strong refractive index modulations are necessary.
Strong refractive index modulations can be obtained inducing surface
corrugation by alternating layers of different materials, one of which
can be air. Few techniques have been proposed for the fabrication of
surface-corrugated fiber gratings, including photorefractive inscription
using etching, femtosecond lasers, and Focused ion beam (FIB). So
far, FIB is the most flexible and powerful tool for patterning, crosssectioning or functionalizing a subwavelength circular MF due to its
small and controllable spot size and high beam current density. In past
two years, a number of ultra-compact surface-corrugated microfiber
Bragg gratings (SCMGs) have been successfully fabricated by FIB
milling. The length of FIB milled SCGMs can be as small as tens of
micrometers. In addition, there are several novel proposals on SCMG
including wrapping a microfiber on a microstructure rod or put amicrofiber on a surface-corrugated planar grating. In this chapter, we
will introduce recent advances in these ultra-small SCMGs and theircharacteristics and applications.

8555-32, Session 7

Large area monolithic organic solar cells
Hui Jin, The Univ. of Queensland (Australia); Cheng Tao, Mike
Hambsch, Almantas Pivrikas, Marappan Velusamy, Muhsen
Aljada, Yuliang Zhang, Paul Burn, Paul Meredith, Centre for
Organic Phototics and Electronics, University of Queensland(Australia)
Although efficiencies of > 10% have recently been achieved inlaboratory-scale organic solar cells, these competitive performance
figures are yet to be translated to large active areas and geometries
relevant for viable manufacturing [1]. One of the factors hindering scaleup is a lack of knowledge of device physics at the sub-module level,
particularly cell architecture, electrode geometry and current collection
pathways. A more in depth understanding of how photocurrent andphotovoltage extraction can be optimised over large active areas isurgently needed. Another key factor suppressing conversion efficiencies
in large area cells is the relatively high sheet resistance of thetransparent conducting anode - typically indium tin oxide [2]. Hence,
to replace ITO with alternative transparent conducting anodes is also ahigh priority on the pathway to viable module-level organic solar cells.
In our paper we will focus on large area devices relevant to submodule scales - 5 cm ? 5 cm monolithic geometry. We have applieda range of experimental techniques to create a more comprehensive
understanding of the true device physics and define sensible boundary
conditions for anode sheet resistance that could help make large
area, monolithic organic solar cells more viable [3]. By employing thisknowledge, a novel transparent anode consisting of molybdenumoxide (MoOx) and silver (Ag) is developed to replace ITO and PEDOTfree large area solar cell sub-modules, acting as both a transparent
window and hole-collecting electrode. The proposed architecture andanode materials are well suited to high throughput, low cost all-solution
processing [4].

[3] H. Jin, A. Pivrikas, K. H. Lee, M. Aljada, M. Hambsch, P. L. Burn, P.
Meredith, Adv. Energy Mater. 2012, DOI:10.1002/aenm.201200254.
[4] H. Jin, C. Tao, M. Velusamy, M. Aljada, Y. Zhang, M. Hambsch, P. L.
Burn, P. Meredith, Adv. Mater. 2012, 24, 2572.

8555-33, Session 7

Improve the open-circuit voltage of organic
photovoltaic devices with PCDTBT: PCBM
heterojunction
Weimin Li, Jinchuan Guo, Shenzhen Univ. (China)
We fabricated the heterojunction organic photovoltaic devices with
PCDTBT as donor and different fullerene dcerivatives with different
LUMO energy levels and side chains as acceptor, and investigatedthe effect of interfacial morphology and temperature on open circuit
voltage. the temperature dependence of current voltage characteristics
was analyzed by an equivalent circuit model. The results suggestthat open circuit voltage is relatively insensitive to interfacial
morphology,and the short circuit current was a function of interfacial
area. The origin of open circuit voltage is ascribed not only to therelative the highest occupied molecular orbital level of a PCDTBT andthe lowest unoccupied molecular orbital level of different fullerene
energy gap but alse to the electronic couplings between fullerene andfullerene,PCDTBT and different fullerene.

8555-34, Session 7

Design of planar lightwave interleavers
based on Echelle gratings structure
Wenkai Liu, Baoqun Li, Xiaowei Dong, North China Univ. ofTechnology (China)
Planar lightwave interleaves, playing the multiplexing/demultiplexing
function, are the key components in the dense wavelength divisionmultiplexing (DWDM) systems. However, the device design and theprocessing errors have significant influence on the device performance,such as insertion loss and crosstalk with the increase in the numberof the device channels and the decrease in the channel spacing. This
paper reports the design procedure of planar lightwave interleavers
based on Echelle gratings structure, introduces two methods toeliminate the device aberration which are two-point aberration-freedesign and elliptical grating facets design repectively. The device
crosstalk and insertion loss is relatively large when the interleavers areworking at higher diffraction series. Proper aberration Compensation
design can effectively reduce the device insertion loss and crosstalk.
Aberration compensation design includes two-point aberration-freedesign and high order aberration compensation design [15]. The twopoint aberration-free design can be achieved by changing the locationof the center point of Echelle grating facet. Higher-order aberration
correction can be achieved by adjust the shape of each grating
facet. The device performance compensation has been compared bysimulation before and after aberration compensation. The 50/100GHz
and 100/200GHz interleavers on the SOI (Silicon-on-insulator) materials
are fabricated, whose actual experiment results match quite well withtheoretical analysis. What’s more, compared with other solutions, theEchelle Gratings Structure planar lightwave interleavers are smaller
and more compact. Moreover, Echelle gratings are fabricated with theconventional semiconductor processing, suitable for mass production
and reducing component cost, and easily to be integrated with othersemiconductor optoelectronic devices to achieve monolithic integration.

References:[1] M. A. Green, K. Emery, Y. Hishikawa, W. Warta, E. D. Dunlop, Prog.
Photovolt: Res. Appl. 2012, 20, 12.
[2] B. Muhsin, J. Renz, K.-H. Drüe, G. Gobsch, H. Hoppe, Phys. Status
Solidi A 2009, 206, 2771.

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Holography, Diffractive Optics, and Applications V
Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8556 Holography, Diffractive Optics, and Applications V

8556-1, Session 1

8556-3, Session 1

Transparent 3D display for augmented reality(Invited Paper)

Comparative analysis on light fieldreconstruction characteristics ofautostereoscopic three-dimensional display
technologies (Invited Paper)

Byoungho Lee, Jisoo Hong, Seoul National Univ. (Korea,
Republic of)Augmented reality (AR) is a recently developed concept that overlays
the artificial data onto various types of sensory input to human from realworld. Especially AR display, which deals with the visual information,is actively investigated among various fields. In this paper, wedemonstrate the transparent 3D display systems, based on the principle
of integral imaging, which are applicable to projection-type AR display
or the optical see-through head mounted display (HMD).
Proposed projection-type transparent 3D display is based on the
concave half mirror array (CHMA). CHMA is a thin transreflective sheet
whose shape is the 2D array of concave mirrors. Supported by thesufficiently thin thickness, CHMA bypasses the real world scene behindthe structure. By projecting proper elemental image onto the CHMA,
the 3D image is reconstructed by reflection because of concave mirror
array structure, resulting in the mixture of 3D virtual image and realworld scene.
We will also demonstrate the integral floating system adopting convex
half mirror to implement the optical see-through HMD. As will be
discussed in the presentation, addressing accommodation response
to farther distance, using integral imaging, requires the pixel pitch ofdisplay device to be reduced. The convex half mirror effectively reduces
the pixel pitch of the display, which, in turn, extends the addressableaccommodation response to farther distance resolving accommodation
mismatch problem of optical see-through HMD.
In the presentation, viable implementation methods of proposed
scheme will be presented. And the characteristics of the proposed
methods will be discussed with the implemented prototypes.

8556-2, Session 1

Fourier holographic display system of threedimensional images using phase-only spatial
light modulator
Hao Zhang, Qiaofeng Tan, Guofan Jin, Tsinghua Univ. (China)
We propose a holographic 3D display system which can produce
images with adjustable viewing parameters and eliminated zero-orderinterruption. The 3D scene is generated from a 3D CAD tool, andpoint source algorithm with anti aliasing technique is used to generate
the holograms. A two-step model is introduced in the computing
to generate precise Fourier holograms. A phase-only spatial light
modulator (SLM) is used in the optical reconstruction, which can replay
clear images for 3D diffusive objects. During optical reconstructing,the viewing angle and image size of the system can be adjusted bychanging the parameters of the replay lens. A filter is introduced in thereplay system to eliminate the zero-order interruption and increase the3D image quality. Optical experiments are performed, and the results
show that our proposed holographic display system can produce
noiseless 3D image reconstructions clearly.

Jae-Hyeung Park, Chungbuk National Univ. (Korea, Republic of)Autostereoscopic three-dimensional displays present three-dimensional
images to users without requiring special glasses. Motivated by asuccess of glasses-type stereoscopic three-dimensional displays,
various autostereoscopic display techniques have been actively
developed in recent years. Multi-view techniques which project different
view images to different viewpoints are considered as practical solution
in current panel resolution. Integral imaging which reconstructs light ray
field without specific viewpoints and holography which reconstructs
wave front using coherent optics are also considered as candidate
technologies for achieving more realistic three-dimensional displays.
In this presentation, we provide a comparative analysis on image
characteristics of these autostereoscopic three-dimensional displays.
For a unified comparison, we analyze light field reconstructed bymulti-view, integral imaging, and holography. Due to different opticalconfiguration and light source coherency, these techniques reconstruct
the desired light field with different spatial and angular sampling,which eventually affects the image quality and viewing limitations. By
analyzing light field reconstructed by three techniques, it is expectedthat not only image characteristics of individual technique can beunderstood but also optimum technique for a given application can be
identified.

8556-4, Session 1

360-degree viewable volumetric 3D floating
display system
Wenping Pan, Nanjing Univ. of Aeronautics and Astronautics(China)A novel spatial three-dimensional (3D) display system is proposed inthis paper. The proposed system takes advantages of both volumetric
3D display and floating display technologies. Volumetric 3D display iscapable of preserving all physiological and psychological depth cues
for human vision system, and presenting 3D images with true physicaldepth. Floating display has the capability of transferring images fromimaging mediums into free space and making penetrable humancomputer interaction (HCI) enabled. We studied the optical path forstatic volumetric display based on spatial matrix of addressable crystal
scatters, which are cracked as spatial voxels embedded in a glass
cube by a technology called laser induced damage, and designed a
GPU-based algorithm for generating depth-coded two-dimensional (2D)
images according to the distribution of the scatters. Depth-coded 2D
image plays a role on trading off 2D solution of projector in the optical
path to get the third dimension for volumetric display. We also studied
the scheme for floating display based on convex mirrors and designed
several experiments for the prototype evaluation. Experimental results
demonstrate that, in the prototype, directly penetrable objects can bedisplayed with true three dimensions at a fresh rate high up to 60 Hertz,
and can be observed from any viewpoints simultaneously by multiple
users, without any special viewing aids.

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Conference 8556:
Holography, Diffractive Optics, and Applications V

8556-5, Session 28556-8, Session 2

3D LED display without glasses and viewer
responses (Invited Paper)

Relationship between individual maximum
disparity and individual comfort disparity invisual comfort of stereoscopic 3D contents

Hirotsugu Yamamoto, Shiro Suyama, Univ. of Tokushima(Japan)Light-emitting diode (LED) panel is suitable for public television andlarge digital signage because of its high brightness and low energy
consumption. Large LED televisions enable many audiences to enjoy
on-the-spot broadcasting of big events, including Olympic games
and World cup soccer games. Showing these sports scenes in 3D
improves sense of reality and excitement. In this invited paper, we
describe our developments of 3D LED display and report movements
and accommodation of a viewer when viewing the developed 3D LED
display without glasses.
We have developed a stereoscopic large television system by use of afull-color LED panel and binocular cameras. In 1998, we developed afull-color stereoscopic 3D (S3D) LED display with polarization glasses.
Then, a full-color S3D display without glasses was realized by use ofa parallax barrier. By introducing black regions between LED lamps,
viewing zones have been enlarged so that a variety of audiences enjoy
the S3D images. We have investigated viewer’s perception of depth
and movements to evaluate the viewing zones. A new configuration of aparallax barrier, called an aperture grille, has been developed in order toenlarge the viewing angle. We have realized 140-inch full-color S3D LED
display without glasses.
As well as reporting the developments of S3D display, we propose aviewing-zone control technique an LED panel. The viewing-zone control
architecture is utilized for S3D display without pseudostereoscopic
viewing positions and 2D LED display with multiple viewing distances.

Zaiqing Chen, Junsheng Shi, Yunnan Normal Univ. (China);
Yonghang Tai, Yunnan Normal Univ (China)
It is well known that some viewers experience visual discomfort
when looking at stereoscopic displays. The disparity is a key factor
influencing visual comfort, and there is a comfortable disparity fora person. In this paper, we explore the comfort zone of horizontal
disparity, which correlates with the optimal viewing distance, asa function of the maximum disparity for an individual. Firstly, theindividual maximum disparities of 14 subjects were measured. Then thesubjects were aske to rate the comfort levels of a 3D video sequencewith different disparity levels, to evaluate the individual comfort
disparities. The results show that as the individual maximum disparity
increased, the corresponding comfort disparity increased, and we
found a correlation coefficient of r=0.946. The average ratio between
the individual comfort disparity and the individual maximum disparity
was approximately 0.72, and this ratio can be used for an individual todetermine the optimal viewing distance by a rapid method.

8556-9, Session 3

10-Gbps RSOA-based upstream
transmission in WDM-PON with MZI-based
equalizers
Ting Su, Beijing Univ. of Posts and Telecommunications (China)

8556-6, Session 2

Binocular and multi-view parallax
images acquisition for three-dimensional
stereoscopic displays
Hongsheng Ge, Xinzhu Sang, Tianqi Zhao, Jinhui Yuan, Junmin
Leng, Beijing Univ. of Posts and Telecommunications (China);
Ying Zhang, Minzu Univ. of China (China); Binbin Yan, Beijing
Univ. of Posts and Telecommunications (China)
Three dimensional (3D) displays have become an attractive frontierresearch area in the last decade. Except for replicating the light
distribution of the 3D scene, the basic idea for the 3D experience isthe stereoscopic vision, which means that the viewer observes a scene
with two similar but slightly different visions with left and right eyes,
and the brain processes the parallax information to be perceived in
3D. The scenes displayed in 3D displays are captured by stereoscopic
image acquisition, and the contents obtained by stereoscopic image
acquisition are finally shown in 3D displays.
In the paper, two and multiple cameras with the same intrinsic
parameters are used to capture a 3D scene from slightly different
directions. Not the same as before, we demonstrated that by setting
the proper distance between the cameras and the location of theconvergent point in this capturing configuration, the displayed 3D scene
with the appropriate stereo depth and the expected effect in front ofand behind the display screen can be obtained directly. The quantitative
relationship between the parallax and the parameters of the capturingconfiguration with two cameras is presented. The capturing systemwith multiple cameras for acquiring equal parallaxes between theadjacent captured images for the autostereoscopic display system isalso discussed. We have experimented to attest the proposed method.
The parallax images captured using the calculated parameters for the
3D display system shows the expected results, which can provide
the viewers the better immersion and visual comfort without any extra
processing.

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Reflective semiconductor optical amplifier (RSOA) has been utilized
extensively in wavelength-division multiplexed passive optical network(WDM-PON). Not only does the RSOA amplify and re-modulate thesignals, but it also provides colorless optical network units (ONUs) torealize cost effective wavelength adaptability. However, the modulation
bandwidth of RSOA is usually limited to 2.5GHz. In this paper, we
propose a 10-Gbps uplink transmission of directly modulated RSOA
with the help of Mach-Zehnder Interferometer (MZI) serving as an
optical equalizer as well as a periodic filter. The model of RSOA is
proved to be able to simulate the commercial RSOA accurately byfitting the dependence of the small signal frequency response (SSFR).
The 3dB-bandwidth of RSOA with MZI increases to >10GHz and theequalization effect is improved considerably. The transmission functionof MZI is certified to be a two-tap optical equalizer with delay time,
coupler factor and initial phase shifts. Given the configuration of thesystem, proper span of the MZI-induced delay time and initial phaseshift have been identified to improve the BER and the eye diagram. A
better received sensitivity of -16dBm at BER=1.1?10-3 which is thethreshold of the Reed-Solomon (255, 223) is obtained after 25-km
SSMF transmission. Experimental and simulation results show that
the MZI with proper delay time and initial phase shift can improve thetransmission performance. We also demonstrate the multiple WDM
channels anchored at the 100-GHz can use a single MZI to equalize theupstream signal.

8556-10, Session 3

Performance analysis of a novel superorthogonal modulation scheme for highspeed optical OFDM system
Qi Zhang, Xiangjun Xin, Lijia Zhang, Yongjun Wang, Chongxiu
Yu, Nan Meng, Houtian Wang, Beijing Univ. of Posts andTelecommunications (China)High speed optical communication is one of the research hotspot

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about optical communication field in the world at present.A novel
super-orthogonal modulation method based on quadrature amplitude
modulation (QAM) and frequency shift key (FSK) is proposed for highspeed optical orthogonal frequency division multiplexing (OFDM)
system. The coding modulation scheme and demodulation-decoding
scheme are designed. The frequency spectrum utilization andtransmission performance of optical OFDM system with proposed
super-orthogonal modulation method is simulated and analyzed. It isalso researched that bit error rate change with different code type. in
optical communication. All the research result will lay the foundation of
optical communication realization with high speed, large capacity andhigh efficiency transmission.

8556-11, Session 4

Frequency shifts of spectral lines inducedby scattering of a truncated polychromatic
plane wave
Jia Li, Yali Qin, Hongliang Ren, Zhejiang Univ. of Technology(China)Within the accuracy of the first-order Born approximation and theparaxial assumption of light waves, the analytical expressions are
deduced for the spectral density of light waves which scatter from aquasi-homogeneous (QH) medium illuminated by a truncated planewave. It is shown that once a polychromatic plane wave firstly diffracts
through Young’s pinholes and then scatters from QH medium, thespectral lines of the resultant field generally displays red shift toward
the lower frequency, closely depending on the scattering angle, thecorrelation length of the scatterer as well as the ratio of the spacing
between pinholes to the distance between opaque screens and thescatterer i.e. d/R. It is further indicated that the red shift of spectrumof scattered light would convert into the blue shift of spectral lines
provided that the correlation length of the scatterer fulfills an enoughsmall value. Effects of these parameters on the evolution of frequency
shifts of spectral lines are specifically analyzed via the numericalapproach, respectively. The theoretical results obtained in this paper
may be of great significance to various experimental aspects, e.g. themeasurement of spectra of scattered light or the determination of theinternal structures of unknown scatterer.

8556-12, Session 4

All-optically manipulated plasmonic
microscope (Invited Paper)Rong Wang, Chonglei Zhang, Changjun Min, Jing Bu M.D., HuiFang, Yong Yang, Nankai Univ. (China); Siwei Zhu, Nankai Univ.
Affiliated Hospital (China); Xiaocong Yuan, Nankai Univ. (China)
A dynamic all-optically controlled surface plasmon polartions (SPP)
novel high-performance multi-function optical microscope, combining
optical microscopic imaging, bio-sensing and surface enhanced Raman
Scattering (SERS) in a single microscopic system, is presented in thistalk. This new configuration uses phase shift of SPP standing wave
generated from sub-wavelength slit arrays embedded in a thin silver
film to achieve super-resolution wide-field microscopic imaging; phasesensitive surface plasmon resonance (pSPR) bio-sensing technology
based on differential phase measurement between radially polarized(RP) and azmuthally polarized (AP) beams to obtain an ultra-highsensitivity and a wide dynamic range simultaneously; the coupling
between the localized surface plasmon (LSP) of metallic nano-particles
and SPP virtual probe with longitudinal electric field to significantly
improve the sensitivity of SERS system. With the integration of thesethree technologies in a single microscopic configuration, the system
can achieve wide-field super-resolved imaging of biological specimens,
ultra-high sensitivity for molecule detection and real-time monitoring
for reaction process of biological samples simultaneously, fulfilling
the requirement of multi-parameter multi-function real-time in-situ

measurement of biological samples. The new microscopic scheme has
great importance in real-time dynamic study on nano-scale biologicalliving cells, and may therefore leads to a strong impact in the design ofnext-generation optical microscope.

8556-13, Session 4

Impact of surface waves on theelectromagnetic enhancement by a metallic
nano-cavity (Invited Paper)
Haitao Liu, Zhiwen Zeng, Nankai Univ. (China)
Enhancement of electromagnetic field has important applications suchas the surface enhanced Raman scattering (SERS) [1]. Metallic nanocavities have been found to be promising structures that can achievea giant electromagnetic enhancement [2]. It has been shown thatnano-apertures under external illumination can launch surface waves
such as the surface plasmon polariton (SPP) [3]. Although it has beenshown in previous literatures that SPPs can play an active role in theelectromagnetic enhancement [4], their exact role in enhancing the field
concentration or resonance has not been clarified at a quantitative level.
In addition, the impact of another so-called quasi-cylindrical wave (CW)[5] on electromagnetic enhancement is rarely addressed. In this report[6], we consider a T-shaped metallic nano-groove to show the impact of
surface waves on the electromagnetic enhancement by a nano-cavity.
It is found that a two-fold higher enhancement factor of electric field
can be achieved compared with a single bare groove without the top
trench. By developing an intuitive model that explicitly incorporates the
waveguide mode resonance in the central groove and the launching andscattering of surface waves in the top trench, we quantitatively showthat the improved field enhancement is attributed to the coupling ofboth surface waves that are collected by the top trench into the central
groove. The present work can be helpful for clarifying the physics of thesurface-wave driving electromagnetic enhancement and for intuitively
designing relevant devices.

8556-14, Session 4

Theory on the quasi-cylindrical wave
diffracted by a sub-wavelength metallic slit
and its enhancement by surface plasmon
resonance
Yann Gravel, Yunlong Sheng, Univ. Laval (Canada)Light scattering by a nano-sized slit engraved in metallic surface is anelementary problem of optical diffraction. In addition to the Surface
Plasmon Plariton (SPP) mode, experiments found an extra field close
to the slit. Its physical explanation gave rise to debate with confusingnames as creeping wave, quasi-cylindrical wave], transient SPP and
Norton wave. In fact, the problem involves calculating the field of anelectrical dipole on a planar metallic surface and dates back to the workof Sommerfeld, but has no known closed solution. Here, we present,
for a nano-slit diffraction, a simple closed form solution consistingof a SPP mode and a scattered field. The asymptotic behaviour ofthe solution close to the slit corresponds to the extra-field previously
observed and takes the form of a flattened cylindrical wave. Farther
from the slit, the solution behaves as a first order cylindrical harmonic
propagating outward from the slit with a diffraction shadow along themetallic surface. Our solution clearly shows that the observed extrafield is not a surface wave but rather the asymptotic behaviour of the
2D scattered field over the metallic surface. Furthermore, the solution
for the scattered field close to the slit shows potential strong resonant
enhancement, depending on the materials and incident wavelength.
The theory is consistent with previous experimental and numericalresults, as well as FDTD simulations, closes the current debate and will
be useful in the design of nano-plasmonic devices.

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Conference 8556:
Holography, Diffractive Optics, and Applications V
REFERENCES[1] W. L. Barnes, A. Dereux, T. W. Ebbesen, “Surface Plasmon
subwavelength optics”, Nature 424, 824-830 (2003);[2] S. A. Maier, Plasmonics: Fundamentals and applications (Springer,
Berlin, 2007);[3] G. Gay, O. Alloschery, B. Viaris De Lesegno, C. O’Dwyer, J. Weiner,and H. J. Lezec, “The optical response of nanostructured surfaces andthe composite diffracted evanescent wave model”, Nature Phys. 2,
262-267 (2006);[4] G. Gay, O. Alloschery, J. Weiner, H. J. Lezec, C. O’Dwyer, M.
Sukharev, T. Seideman, “Surface quality and surface waves on
subwavelength-structured silver films”, Phys. Rev. E 75, 016612 (2007);[5] P. Lalanne, J. P. Hugonin, “interaction between optical nano-objects
at metallo-dielectric interfaces”, Nature Physics 2, 551-556 (2006);[6] B. Ung, Y. Sheng, “Optical surface waves over metallo-dielectricnanostructures: Sommerfeld integrals revisited” Opt. Express 16, 90739086 (2008);[7] P. Lalanne, J. P. Hugonin, H. T. Liu, B. Wang, “A microscopic viewof the electromagnetic properties of sub-? metallic surfaces”, Surface
Science Reports 64, 453 (2010);[8] G. Lévêque, O. J. F. Martin, J. Weiner, “Transient behaviour ofsurface plasmon polaritons scattered at a sub-wavelength groove”,
Phys. Rev. B 76, 155418 (2007);[9] Y. Gravel, Y. Sheng, “Rigorous solution for the transient surface
plasmon polariton launched by sub-wavelength slit scattering”, Opt.
Express 16, 21903-21913 (2008);[10] A. Y. Nikitin, s. G. Rodrigo, F. J. Garcia-Vidal, L. Martín-Moreno,“In the diffraction shadow: Norton waves versus surface plasmon
polaritons in the optical region”, New Journal of Physics 11, 123020(2009);[11] A. N. Sommerfeld, “Propagation of waves in wireless telegraphy”,
Ann. Phys. (Leipzig) 28, 665-737 (1909);[12] J. Zenneck, “Propagation of plane EM waves along a plane
conducting surface”, Ann. Phys. (Leipzig) 23, 846-866 (1907);[13] K. A. Norton, “The propagation of radio waves over the surfaceof the earth and in the upper atmosphere”, Proc. IRE 24, 1367-1387(1936);[14] R. E. Collin, “Hertzian dipole radiating over a lossy earth or sea:
Some early and late 20th-century controversies”, IEEE Ant. And Prop.
Mag. 46, 64-79 (2004)

8556-15, Session 4

Enhanced subwavelength light spot ofvertically-tapered metallic aperture based on
plasmonics
Junbum Park, Kyungho Kim, Il-Min Lee, Dawoon Choi,
Byoungho Lee, Seoul National Univ. (Korea, Republic of)
We propose an approach that improves the characteristics of a
subwavelength light spot with a tapered metallic aperture without
increment of the subwavelength spot size. Two advantageous featuresof the proposed tapered structure are investigated: At first, by enlarging
the effective area of the aperture, the structure could collect more
light compared to the regular one. Thus the funneled light contributes
to the field enhancement. Furthermore, the tapered edges of the exit
surface of the aperture provide confined field, a wedge mode, which isbounded strongly and enhances the local electric field around the edgeof the aperture. The enhanced characteristics of subwavelength spot invertically-tapered aperture, including peak intensity, power throughput,and full width half maximum (FWHM) were obtained numericallyusing finite difference time domain (FDTD) method. The proposed
device is fabricated using conventional planar fabrication techniques
and focused ion beam (FIB) milling to realize the tapered structure.
The relative tapered angle-dependent enhancements are presented
with experimental and quantitative demonstrations of the proposed
structure.
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8556-16, Session 5

Tunable nano-pattern generation based on
surface plasmon polaritons (Invited Paper)
Chinhua Wang, Soochow Univ. (China); X. Fy, Zhejiang Normal
Univ. (China); Yiming Lou, Cao Bing, Soochow Univ. (China)
We present a numerical observation of a tunable 1D and 2D nanopattern generation and photolithography technique based on a surface
plasmon resonant cavity formed by a metallic grating and a metallic
thin-film layer separated by a photoresist layer. The tuning capability
is implemented by varying the cavity length combined with thepolarization of the incident light, from which different surface plasmon
interferometric patterns with inherently higher optical resolution thanthat of conventional surface plasmon techniques are generated in
the cavity of photoresist layer. The physical origin of the tunability is
analytically confirmed by the dispersion relation derived from the cavity
system as well as the interferometric behaviors of the surface plasmon
polaritons. The technique opens a new possibility to generate tunableultra-deep subwavelength patterns by using a fixed diffraction-limited
mask with capability of large area, deep exposure depth and flexibilityof arbitrary 2D patterns.

8556-17, Session 5

Metallic superlens design using the longrange SPP mode cutoff technique
Guillaume Tremblay, Jing Wang, Yunlong Sheng, Univ. Laval(Canada)In applications of the metallic near-field imaging superlens to nanoscale resolution lithography, the image quality is a critical issue.
Moreover, the object as a metal coated photomask forms an additional
metal layer, which can also support the Surface Plasmon Polariton(SPP) modes. Although the fundamental Fourier analysis still apply
with the transfer function computed by the transfer matrix, the SPP
resonance and the SPP waveguide theory, the object field should becomputed by the scattering of nano-scaled object detail, which isrelated to object topographic profile in a complex manner. In the caseof metal object, the presence of neighbouring object points impacts
the formation of the electrical dipole at that point. As a result, one uses
no longer the impulse response, but the two-slit image resolution as ameasure of merit. To avoid designing the metallic superlens by random
trials in the numerical FDTD method, we find the transfer function of
the superlens represents, in many cases, is determined by the SPP
waveguide modes along the superlens layer. We propose the longrange SPP mode cut-off technique to flatten the transfer function. We
model the metallic superlens with metal object as a dielectric multireflecting resonator formed by two metal layers, which are themselvesmulti-reflecting SPP resonator. We trim the transfer functions of thethree resonators by adjusting the thicknesses and the permittivity ofeach layer to optimize the total transfer function. The genetic algorithm
is used for the optimization. Design examples are all confirmed by thereal image computed with FDTD.

8556-18, Session 6

Digital holographic display for a single user
(Invited Paper)
Joonku Hahn, Kyungpook National Univ. (Korea, Republic of);Hwi Kim, Korea Univ. (Korea, Republic of)Digital holography has been regarded as the technology to realize
an ideal three-dimensional display. Even though this technology wasinvented a number of decades ago, many people think there are still
many problems for holographic display to be commercialized. The main
problem is that the holographic displays generally need enormous data

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capacity in comparison with other traditional display. But spatial light
modulators have only small space-bandwidth product. So, there is atrade-off between screen size and field of view in holographic display.
There have been two major approaches to achieve a reasonable screen
size. One is to increase the space-bandwidth product of spatial light
modulators. The other is to sacrifice the field of view to get large screen
size. The latter has an advantage to design a system with small spatialbandwidth product. So it is possible to build a system with spatial light
modulators already in market. For this approach, we need to define ourtarget as a holographic display for a single user. In this paper, we will
introduce two kinds of digital holographic displays which are recently
studied. One is a holographic display with a large-scale spatial light
modulator and the other is a holographic display with a small-scalespatial light modulator and projection optics.

A common-path and parallel phase-shifting point-diffraction
interference microscopy is proposed based on a cube beamsplitter
pair. Together with the parallel phase-shifting scheme, slightly-off-axis
interferometry for microscopy is performed, which suppresses dc termby subtracting the two phase-shifting holograms from each other. The
setup is stable due to its common-path configuration, and can be used
for measuring moving object or dynamic process.

8556-19, Session 6

Zernike phase contrast microscopy is extended to perform quantitative
phase measurement for microscopic object by combining with thephase-shifting technique. The extended microscopy uses dozens
of periodic point-like light sources on a ring for illumination, andcorresponding point-like phase-shifters for phase retardering theundiffracted component of object wave. By shifting the phase shifters
with different height (to cover the undiffracted components), the phaseshifting can be performed. The method has low coherent noise level
due to the partially-coherent illumination. Besides, it has higher lateral
resolution because of the synthetic-aperture of the oblique illumination.

In-line phase shifting digital holography
based on LCOS

8556-21, Session 7

Spozmai Panezai, Dayong Wang, Jie Zhao, Yunxin Wang,
Beijing Univ. of Technology (China)

A JPEG-based enhanced compression
algorithm of digital holograms

The phase shifting digital in-line holographic microscopy is a powerful
method for 3-D imaging with high resolution and capabilities of tracing
moving objects. The phase shifting removes the distortion comingfrom twin images while optimizing the space-bandwidth product of thedetector due to the absence of carrier fringes in the recorded hologram
which limits the resolution in case of the off-axis configuration. In thispaper the liquid crystal on silicon spatial light modulator (LCOS) is used
to introduce the phase modulation in the reference beam in the in-line
configuration based on Gabor like setup. In this experiment the object isplaced between condenser lens and LCOS, so the wave front diffracted
from the object is focused on the LCOS which changes only the phaseof the DC term (non diffracted light) of the object’s spectrum. So that wewill record the phase shifted holograms in time sequence by modulating
the LCOS pixel which spatially coincides with DC term. Then theconventional phase shifting algorithm is applied to recover the complex
amplitude distribution of the object and it is digitally propagated to theobject plane. The obtained experimental results are then compared withthe results obtained from Gabor’s approach .The comparison will showthat the proposed method has a better image quality and even works
for a highly non-tansmissive object.

Hanming Yu, Zibang Zhang, Jingang Zhong, Jinan Univ. (China)

8556-20, Session 7

Common-path phase-shifting digitalholographic microscopy (Invited Paper)
Baoli Yao, Peng Gao, Junwei Min, Xi’an Institute of Optics andPrecision Mechanics (China)
Digital holographic microscopy (DHM), combining optical interferometry
and microscopy, is a whole-field optical technique for measuring profile,
thickness or refractive index distribution of microscopic specimen.
It has the advantages of nondestructive, high-resolution, highmeasurement speed, requiring no extra preparation on specimen. Thus,
it has been widely used in biology, medical science, micro-fabricationindustry, and so on. To solve the problems of stability, spatial resolution
and speed, we investigated the DHM based on common-path
configuration and parallel phase-shifting mechanism.
A common-path and in-line point-diffraction interferometer for
quantitative phase microscopy is proposed. The magnified tested
wave is split by a diffraction grating into two copies. One copy is recast
for reference wave through pin-hole filtered in the Fourier plane; theother one is still used as object wave. After diffracted by the second
grating, the two waves propagate on-axis into the CCD camera.
Achromatic phase-shifting is implemented by linearly moving one of
the two gratings in grating vector direction. The setup has advantagesof less sensitive to environmental vibration due to the common-path
configuration.

Digital holography is a successful technique for recording andreconstructing 3-D objects. But digital holograms contain a large
amount of information and occupy large amounts of bandwidth andmemory space. For the efficient storage and transmission of digitalholograms, an appropriate compression algorithm is necessary. We
present a JPEG based enhanced compression algorithm of digitalholograms as a modified version of the general JPEG encoder. Since
digital holograms, unlike general images, are characterized by mostof the information concentrated at their first-order component, tocompress digital holograms only with their first-order component isavailable. JPEG is a commonly used method of lossy compression
for digital images and based on human visual system. To make thegeneral JPEG fit the character of digital holograms, we propose the
JPEG based algorithm to obtain more efficient compression ratio andmaintain the compatibility. The algorithm divides digital holograms
into 8?8-blocks and performs 2D-DCT(discrete cosine transform) on
each of them, as the general JPEG. Then it extracts the low-frequency
section where the first-order component locates with an adaptive mask
according to the DCT coefficients distribution. Next, the algorithm
quantizes the masked coefficients with the general JPEG quantizationtable and encodes them with Huffman encoding finally. Compatible withthe general JPEG, the compressed holograms can be directly decodedby the general decoders. Our simulation and experimental results showthat this algorithm has higher compression ratio than the general JPEG
and more accurate retrieved phase while the compression is equal.

8556-22, Session 7

Effect of phase-shift step on hologram
reconstruction in Fresnel incoherent
correlation holography
Hao Chen, Yuhong Wan, Tianlong Man, Zhuqing Jiang, Dayong
Wang, Shiquan Tao, Beijing Univ. of Technology (China)
Fresnel Incoherent Correlation Holography (FINCH) enables holograms
to be created from incoherent light illumination of 3D objects. The
optical setup of FINCH is usually simple and compact owe to its inline geometry while the reconstruction of hologram suffers from theobstruction of zero-order item and twin image. Phase-shift technology
is combined with FINCH in order to obtain zero-order-free and twinimage-free reconstruction. Three-step phase-shifting is adopted
in all the publications of FINCH and the application of other multistep phase-shift technology in FINCH are not investigated yet. The
Fresnel holograms are sequentially recorded with different multi-step

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Conference 8556:
Holography, Diffractive Optics, and Applications V
phase shift (including four, three, and two-step) to form the complex
hologram and the quality of the reconstructed images are comparedby simulations and experiments respectively in this study. The qualityof the reconstructed images is evaluated by resolution of system andthe single-noise ratio(SNR). Although various noise would be inducedby the optical elements and the experimental environment in practice,
four-step phase-shifting technology still offer the best reconstructed
image. According to the results, It’s founded that four-step phaseshifting provides the best quality of the reconstructed image but thesystem resolution is not different from two, three-step phase-shifting.
At present, multi-step phase-shifting in FINCH is realized by multiexposure sequentially, therefore it is not suitable for imaging of the
dynamic samples and processes. The feasibility and reconstruction
characteristics of multi-step phase-shifting with single-shot in thissystem is analyzed.

8556-24, Session 7

Detection of silver ions induced
morphological changes on E. coli membraneusing digital holographic microscopy
Farzaneh Borji Monfared, Ali Mohebbi, Zanjan Univ. (Iran,
Islamic Republic of); Ali-Reza Moradi, Institute for Advanced
Studies in Basic Sciences (Iran, Islamic Republic of) and Optics
and Photonics Research Ctr. (Iran, Islamic Republic of)
The Digital holographic microscopy is a non-destructive andquantitative phase contrast microscopy technique that is suitable formarker-free investigations of living cells and organelles. In this work,
we utilize this technique and also conventional video microscopy todetect the dynamic morphological changes of bacteria membrane inpresence of silver ions. Silver ions have shown strong inhibitory effects
on bacteria and can be used as antibacterial. We used E. coli as asample and the influences of the ions were compared in terms of thevariations in volume and roughness of E. coli for different concentrationof silver ions in the buffer and various incubation times. In a controlled
experiment using a microinjecting pump the concentration of
antibacterial is increased, the movement of a single or a set of bacteria
are monitored live, and successive digital holograms are recorded.
The recorded holograms by digital camera can be post-processed tothree dimensional reconstruction of the samples and measurementof quantitative structural changes in various interacting time of thebacteria.

8556-45, Poster Session

Numerical simulation of polarization
dependent characteristics of the structured
thin-films phase grating
Yiyu Li, Chuan Hu, Yuchen Wu, Haihua Feng, Jiaojie Chen,
Wenzhou Medical College (China)
Diffraction efficiency of the structured thin-films phase grating (STFPG)
at the visible wavelength is analyzed by the rigorous coupled wave
analysis (RCWA) method demonstrating that the TM polarization canbe seperated from the 0th transmitted order of the TE polarization by±1st order diffraction. The far field diffraction pattern is simulated by thefinite-difference time-domain (FDTD) method to show the polarization
beam splitting process of the STFPG at wavelength of 633nm. In thenear field, polarization dependent Talbot effect of the STFPG is alsoelaborated. FDTD simulations reveal that the spatial distribution of theinterference fringes forming the self-image of the STFPG can be shiftedby a half of grating period by changing the incident wave polarization
within a particular wavelength range.

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8556-46, Poster Session

A novel iterative computation algorithm forkinoform of 3D object
Xiaoyu Jiang, Pei Chuang, Yantao Zong, Jia Wang, Academy ofArmored Force Engineering (China)
A novel method for computing kinoform of 3D object based on
traditional iterative Fourier (GS) algorithm is proposed in this paper.
Kinoform is a special kind of computer-generated holograms(CGH), which has very high diffraction efficiency since it modulates
the phase of illuminated light only and doesn’t have disturbancefrom conjugate image. The traditional GS arithmetic assumes thatreconstruction image is in infinity area(Fraunhofer diffraction region),and ignores the deepness of 3D object ,so it can only calculate twodimensional kinoform.The proposed algorithm in this paper divides
three-dimensional object into several object planes in deepness
direction and treat every object plane as a target image, then iterative
computation is carried out between one input plane(kinoform) andmulti-output planes(reconstruction images) .A space phase factor
is added into iterative process to represent depth characters of 3D
object, then reconstruction images is in Fresnel diffraction region. A
lookup table is used to reduce the influence of phase factor operation
to the speed of iterative calculation. Optics reproduction experimentof kinoform computed by this method is realized based on liquidspatial light modulator. Mean Square Error(MSE) and Structure
Similarity(SSIM) between original and reconstruction image is used toevaluate this method. The experimental result shows that this algorithm
computational and convergent velocity is fast and the result kinoform
can reconstruct matching object plane in different distance with highprecision under the illumination of plane wave. The reconstruction
images provide space sense, which has three-dimensional vision effect.
At last, the influence of space and shelter between different object
planes to reconstruction image is also discussed in the experiment.

8556-47, Poster Session

Combination of electronic speckle patterninterferometry and digital image correlationfor 3D deformation measurement
Xinghua Chai, Naiguang Lv, Xiaoping Lou, Beijing Information
Science & Technology Univ. (China)
Electronic Speckle Pattern Interferometry (ESPI) and Digital Image
Correlation (DIC) are two whole-field , non-contact experimental
techniques that enable rapid and highly accurate 3-D measurements ofscattering surfaces. Electronic Speckle Pattern Interferometry needs aphase-shifting setup and rotating the whole device for 3-D deformation
measurement. These operations are especially inconvenient to dataacquisition of deformations in three directions simultaneously andincrease the system deviation. Digital Image Correlation using one
CCD camera can acquire 2-D information of displacement. Another
CCD camera needs recording speckle image simultaneously for 3-D
measurement. The matching of images recorded by two CCD cameras
may introduce extra deviation. The combination of the two techniques
is an effective method to diminish these deviations and simplify
experiments. Electronic Speckle Pattern Interferometry setup for outplane measurement and Digital Image Correlation setup using one
CCD camera for in-plane measurement constitute one measurement
system. Three dimensions information of deformation can be recorded
simultaneously. The former can measure 3-D deformations or shape ofcomplex amplitude in nanometric level. The latter can measure small
displacement in micrometric level. Thus matching for measurement
ranges and precisions of the two techniques is very important. Key
factors effecting the matching including laser wavelength, phaseanalysis of speckle fringe pattern, sub pixel fitting are discussed in thispaper.

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8556-49, Poster Session

8556-51, Poster Session

Speckle reduction by spatial light modulator
in digital holography

Research of fabricate large scale pulse
compression grating by multiple exposure

Puhui Meng, Dayong Wang, Shifeng Chang, Shiquan Tao,
Beijing Univ. of Technology (China)

Chaoming Li, Soochow Univ. (China)

A speckle noise reduction method is proposed in digital holographyusing angular diversity based on phase only SLM (spatial light
modulator) device. Laser as a light source, it has very high coherence,and is widely used in digital holograph systems. Coherent lightilluminates the object and interfered by another coherent light calledreference light. The Interference pattern is recorded by CCD as thehologram. Since the speckle noise phenomena can be found in mostof coherent light illumination conditions, so the laser character of thehigh coherence also brings the speckle noise into digital holography
and greatly worsens the quality of holograms. In this paper, weanalyzed the SLM device’s working principle and discussed the speckle
reduction method with speckle theory. This article mainly focuses on
the method of changing the angles of the illumination light. We analyzed
the relationship between the speckle phenomena and the illumination
angle. By compared the maximum modulation angle that SLM device
can reach with the essential minimum angle, we proved that phase only
SLM device can perfectly modulate the illumination light and reduce
system speckle noise in theory. With the help of SLM device, theillumination light could be modulated faster end more accurately thanother methods. We constructed a digital holography setup with phase
only SLM device. In experiments, a series of results of USAF test target
were obtained, and the results showed that the speckle noise in digitalholography system was obviously reduced by phase only SLM device
and the speckle contrast ratio dropped to 36% of the initial value.

Pulse compression grating plays very important role in the laser
confinement fusion system. Along with the development of laser
confinement fusion project, more and more large scale gratings
are needed. Holographic technology is very important means to
manufacture large scale gratings, but the scale of gratings is limitedby the recording system. In order to fabricate large scale pulse
compression grating, the method by exposure several times to fabricate
large scale mosaic gratings is investigated in the paper. The method
uses the recorded part of grating as a detecting standard to test thephase situation between the recording light wave and the recorded
grating. By using stripes locking system to control the phase of light
wave, the goal of manufacture large scale compression mosaic grating
have be achieved. At last, the mosaic grating experiment is studied.
The grating frequency is 1740lp/mm , the size of exposure unit is
200mm?200mm. The experiment results show that the method canachieve high precision alignment, and can be used to fabricate large
scale grating.

8556-53, Poster Session

Defect mode in a one-dimensional photonic
crystal with a dielectric-superconducting
pair defectJi Jiang Wu, Jinxia Gao, Shandong Univ. of Technology (China)

8556-50, Poster Session

Iterative partial quantization method for theerror reduction of low-quantized kinoforms
Shiyuan Yang, Seiichi Serikawa, Kyushu Institute of Technology(Japan)A kinoform with low phase modulation levels is desirable from thepoint of view for fabrication, but the quantization error will disturb
the reconstruction seriously. Various optimization algorithms had
been suggested and the iterative stepwise quantization method can
reduce the quantization error much with few calculation time. In thisstudy, we suggest an iterative partial quantization method to improve
the performance of the conventional iterative stepwise quantization
method. The strategy of stepwise quantization is to increase thequantization interval around the quantization values with the general
Fourier repetition algorithm to concentrate the phase distribution aroundthe quantization values so that the quantization error can be reduced. It
is powerful for the error reduction of low-quantized kinoforms, but thephase distribution could not be concentrated to the phase quantization
values completely, especially a number of phase values remain far fromthe quantization values. We modify the conventional iterative stepwise
quantization method by using an iterative partial quantization method
to decrease the phase distribution far from the quantization values.
The iterative partial quantization method uses the same process of
stepwise quantization but only partial points of kinoform phase arequantized. This partial quantization gives a relaxation of kinoform phase
constraint in the Fourier repetition. The conventional iterative stepwise
quantization process is performed after the iterative partial quantizationand the phase distribution far from the quantization values decreases
so that the reconstruction error can be reduced.

The one-dimensional dielectric photonic crystals(PCs) with complex
defect layers, consisting of superconducting (SC) and dielectricsublayers are theoretically studied. Transfer matrix method (TMM)
has been used throughout this study. The influence of a substitutional
defect on the transmittivity spectra is analyzed for normal incidenceof light on the structure. The two-fluid model and wavelengthdependent dispersion formula were adopted to describe the opticalresponse of the low temperature superconducting defect sublayer.
The pronounced difference in the transmittivity spectra of the photonic
crystals with right-handed (RH) and left-handed (LH) positions of thesuperconducting defect sublayer with respect to the dielectric defectsublayer is demonstrated. We have showed that in contrast to the usual
defect modes, the position of the defect modes is nearly invariant withthe position of the defect layer from one end to the other end of the PC.
It is observed that, for the case of RH SC defect sublayer, the positionof the defect mode and the transmittivity at the defect mode frequency
strongly depend on the thickness of the superconducting sublayer aswell as on the temperature. It is also shown that in contrast to the caseof the PCs with RH SC defect, the defect modes of the PCs with LH SC
defect sublayer are nearly invariant upon the change of the thickness ofthe superconducting sublayer and the temperature. This study may bevaluable in designing optical devices.

8556-54, Poster Session

Effective design of diffractive opticalelements for beam splitting with SA
algorithm
Hui Pang, Shaoyun Yin, Qiling Deng, Institute of Optics andElectronics (China); Yongqi Fu, Univ. of Electronic Science andTechnology of China (China); Chunlei Du, Institute of Optics andElectronics (China)
Simulated annealing algorithm (SA) can find the global optimal solution
and is widely used for solving the stochastic optimization problems

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Conference 8556:
Holography, Diffractive Optics, and Applications V
in physics and engineering. Though the SA algorithm could achieve
lower uniformity error and higher diffraction efficiency compared tothe iterative Fourier transform algorithm in the design of the diffractive
optical element (DOE), such as for beam shaping, pattern generation
or beam splitting, the time taken by SA algorithm is unacceptable,
for the large number of sampling point of DOE designing. By using
the character of periodic DOE, an effective method for the design ofphase only and quantized DOE for beam splitting with SA algorithm
is presented. The relation of the parameters of the DOE including thesampling size, number of sampling point, divergence angle and output
field size are analyzed, and the elimination method of high diffraction
orders is given. It concludes that when the desired output field size only
takes a quarter of the total diffraction field, the high diffraction orders
could be eliminated effectively. Simulation result shows that this method
could greatly reduce the time of beam splitter’s design compared tothe original method and keep the higher diffraction efficiency and lower
uniformity error compared to the iterative Fourier transform algorithm.

phase differences between the sampled points of reconstruction.
The phase differences have the range of two times the phase period
and we restrict them into half of the phase period after wrapping
the phase differences. This strategy can successfully avoid theexistence of isolated zero points so that speckles can be eliminated.
The phase difference constraint process can be incorporated into
the general iterative algorithms for the optimization of a kinoform.
Speckleless reconstruction can be obtained after a sufficient numberof iterations and the also the kinoform conditions are satisfied (i.e., thekinoform amplitude uniform condition and its phase quantization). In
addition, this speckleless reconstruction has noise immune when thereconstruction phase noise is under a quarter of phase period. We willshow some simulation results to show the effect of the iterative phasedifference constraint method for the speckle elimination of kinoforms in
our presentation.

8556-55, Poster Session

Optical correlation recognition based on
LCOS

Computer simulation and optimization
design of the holographic photonic crystal
template fabrication process
Ying Liu, Academy of Armored Force Engineering (China)
According to the holographic multi-beam interference theory, threedimensional (3D) holes structure can be recorded in photosensitive
materials and 3D photonic crystals can be generated by filling inhigh refractive index materials. Among the fabrication approaches ofphotonic crystals, holographic lithography method has a number ofadvantages, e.g. ability to create large volume of periodic structures,the uniformity of period, and more degrees of freedom to control thestructures. It has been demonstrated theoretically that 3D structures
can be obtained by recording the interference patterns generated byfour coherent laser beams on photosensitive materials. This techniqueproduced defect free, nanometer-scale structures over large substrateareas in a single step fabrication. However, in four-beam interference
approach, many factors in photonic crystals fabrication must be
considered. Such as different included angle between two interference
beams generates different lattice structure, the polarization directionsof the beams affect the contrast of the interference fringes and makethe shape and lattice structure changed with the polarization direction
adjustment. For these reasons, the included angle between the beams,
the polarization states of the beams and the intensity ratio must be
adjustment simultaneously in the process of fabricating holographic
photonic crystal templates. Based on the theory of lattice pattern
simulation with multi-beam interference, the process of generation ofholographic photonic crystal templates in photoresist is simulated bymatlab program. The incident light direction, beam polarization andlight intensity in the optical path of fabricating fcc structure and theexposure and development time in the fabrication process are analyzed
theoretically. A set of optimized parameters of the optical path andexposure and development time are presented in this paper.

8556-56, Poster Session

Iterative phase difference constraint method
for the speckle elimination of kinoforms
Toshinori Hora, Shuan Yang, Seiichi Serikawa, Kyushu Instituteof Technology (Japan)
Speckle noise is a serious problem in the reconstruction of computergenerated holograms (CGHs). Especially for a kinoform (a phaseonly CGH), the speckles lead to a large reconstruction error and it isimportant to eliminate the speckles. The speckles are caused by theisolated zero points in the reconstruction of a CGH, so the speckles
can be avoided if there are no isolated zero points. In this study,
we suggest a new method that restricts the existence range of the

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8556-58, Poster Session

Mingchuan Tang, Soochow Univ (China); Jianhong Wu,
Soochow Univ. (China)
Due to the characteristics of high-speed and parallelism during theinformation processing, the real-time optical correlator is widely used
for pattern recognition in the fields of missile guidance, spacecraft
docking, landing and biometric. The traditional real-time Vander Lugt
correlators use LCD or ferroelectric liquid crystal spatial light modulator(FLC) as the matched filter, but the modulation curve of the LCD iscoupled , which will reduce the optical efficiency, while the FLC merely
has two states(0 and p) leading to a low signal-to-noise ratio. Severing
as a phase-only matched filer, LCOS has been adopted in the correlator
for the recognition of the letters without distortion. Attributed to thelarge open rate, uniform amplitude and continuous phase modulation
characteristics of the LCOS, the filter will improve the optical efficiency
and signal-to-noise ratio substantially. Allowing for the distortions of theobject to be identified including rotations, scale changes, perspective
changes, which can severely impact the correlation recognition results,
in this paper, a modified real-time Vander Lugt correlator based on the
LCOS is presented by means of applying an optimization algorithm
to the design of the filter so that the correlator can be invariant to the
distortions while maintaining good recognition performance. In thefrequency domain, the filter is synthesized by the linear combinationof the phases of the training images covering a certain distortion,
meanwhile the weights of the linear combination are calculated by
the successive forcing algorithm, then the new correlator will get thesimilar recognition results for all the training images. Moreover, themodified filter is dominated by the higher frequency signal based on the
combination of the phases, it will have higher identification rate.

8556-60, Poster Session

Design and fabrication of aluminum
nanowire-grid polarizer in near-infrared
broadband
Qiufeng Jin, Quan Liu, Jianhong Wu, Soochow Univ. (China)
Polarizers and polarizing beam splitters are essential optical devices formost optical systems and optical networks. The infrared polarizers arewidely used in the infrared imaging systems as the core components,
such as infrared stealth, target acquisition and mine detection,
automobile night-vision instrument and other systems. Generally inorder to distinguish the object emission from the reflection, infrared
polarizers are used as a filter of the infrared camera.
Aluminum is a high-performance functional material used as the metal
layer of Sub-wavelength metal wire grid. Holographic lithography
is widely used in nano-fabrication process for its larger scale, highefficiency, low cost. But the most severe limitation of holographic

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lithography arise when resist exposures are performed on reflecting
substrates (Al) which will produce strong standing waves, and it’sdifficult to yield a well resist profile which can be used as the mask forthe post dry etching.
In this paper, a thin layer of Cu, which worked as the substrate of resist
for holographic exposure, is deposited on the Al layer, and the standing
wave is effectively suppressed. The following aspects are analyzed.
(1) The reflection on the substrate is suppressed with the optimal Cu
layer thickness. In the conditions of 413.1nm recording wavelength and
250nm~350nm grating period, the reflectivity of the resist-substrateinterface is calculated with a aluminum layer(150nm to 250nm),copper
layer(5nm to 50nm).After trade-off between the resist-substratereflectivity and the final performance of the polarizer, the structure witha Al layer 190nm, and anti-reflection Cu layer 40nm is chose.
(2)According to the optimal thickness of Cu layer, the exposure doseis calculated. The distribution of intensity of incident irradiation inresist during exposure is figured out, and it is shown that the pattern inresist on surface with high reflectivity will suffer standing wave due tothe fact that the incidence irradiation interferences with the reflective
beam from the resist-substrate interface. Combining with parameterof the lithography process in our laboratory, the concentration of
the developer is adjusted and the time of the development is also
optimized. Ultimately, the desired start exposure dose is reached.
(3)The affect of the residual Cu layer to the performance of the polarizer
is simulated. Optical performance of a bilayer nanowire-grid polarizer isanalyzed by FDTD method with a residual Cu layer(5nm to 40nm). The
results show that the bilayer nanowire-grid polarizer obtained the TM
transmittance>85%, extinction ratio>30dB. No significant difference
between the pure aluminum and copper residues grating is found.

8556-61, Poster Session

3D measurement for volume holograms in
Fe:Cu:LiNbO3 crystal by dual-wavelength
digital holographic microscopy

8556-62, Poster Session

Improving the phase measurement by theapodization filter in the digital holography
Shifeng Chang, Dayong Wang, Yunxin Wang, Puhui Meng, Jie
Zhao, Beijing Univ. of Technology (China)
Since the limited aperture of the CCD target surface, the point spreadfunction of digital hologram reproduction system has high sidelobe,
which leads to significant diffraction effects in the reproduction process
and reduces the quality of the reconstructed images. In addition,
the presence of laser speckle and other noise also make the phasemeasurement accuracy of the object be decreased.
In this paper, the apodization filter is applied to improve the phasemeasurement in the digital holographic microscopy imaging system.
The sidelobe energy of the imaging system can be reduced by
the apodization to suppress the border diffraction. First, a novel
reconstruction method based on extension and apodization of thedigital hologram is presented, by which the original hologram can beextended through filling the average intensity values of the boundary,and the extended hologram is apodized by use of the constructedwindow function. Second, the light wave propagation of digitalhologram reproduction is explored by numerical simulation to analyze
the apodization function on cutting diffraction effects and noise effect.
Third, the experimental system of the lensless Fourier transform digitalholography is set up, and the apodization method is applied to thestructure measurement of a phase grating with the grating constant
300&#61549;m and depth 150nm. Finally, the results are compared tothe detection data given by the light interferometer. Simulations andexperiments demonstrate that apodization can effectively reduce theborder diffraction and noise effects to improve the phase measurement
precision and the quality of the reconstructed images.

8556-63, Poster Session

Zhirui Gao, Zhuqing Jiang, Yujia Wang, Jiangtao Wu, Yunxin
Wang, Beijing Univ. of Technology (China)

Rectification of gridline structure in
integral image using radon transform andperspective transformation

The technique of digital holography has experienced substantial
developments in the past years as charge coupled device (CCD) anddigital image processing technologies progressed.

Bi-yun WANG, Yang Song, An-zhi He, Nanjing Univ. of Scienceand Technology (China)

However, when the optical depth of an object is greater than the
wavelength, the phase image contains 2p discontinuities, and numericalunwrapping procedure could not be applied to obtain phase informationof the objects which have a high aspect ratio. Two wavelengths areused to produce a longer wavelength called the ‘beat wavelength’ indual-wavelength phase unwrapping.

Integral imaging is one of the most promising techniques for capturing
and displaying the three-dimensional information of the object. Most
integral image analysis and processing tasks require each elemental
image can be identified with high precision, which is difficult toimplement in a real pick-up process. For the acquisition of the threedimensional information in integral imaging process, the lens arrayshould be aligned precisely with respect to the CCD. In this paper,
we present a method to accurately correct geometric distortions
triggered by the misalignment between lens array and CCD. The
method for calculating the skew angle of deviation and the accurate
gridline structure in the three-dimensional integral images is basedon the Radon Transform algorithm. Then using projective imagetransformation, the geometrical distortion in the elemental image set
can be rectified. The size and position information of the rectified
element images also can be calculated by the gridline structure, which
will prevent the image splitting, shifting along the lateral or longitudinal
direction, or blurring according to reconstruction distance in the opticalor computational reconstruction process.

In this paper, the phase-type grating recorded in a 2-mm-thick
Fe:Cu:LiNbO3 crystal is measured by dual-wavelength digitalholography. In the experiment, a volume hologram, which is recorded
in a 2-mm-thick Fe:Cu:LiNbO3 crystal by interference of two recording
beams at the wavelength of 532 nm, is reconstructed to be imaging
by dual-wavelength digital holography. Two lasers of the different
wavelengths 660 nm and 671 nm are used to obtain a larger beatwavelength. Each laser output, which is spatially-filtered and collimated,is split into a reference and object beams in an interferometer setup
based on the Mach-Zehnder configuration. In dual-wavelength phaseunwrapping, two individual phase images are obtained by using eachwavelength, respectively, and the phase image for beat wavelength isobtained by subtracting one single wavelength phase image from theother and then adding 2p whenever the resultant value is less than zero.
In the final synthetic image, the discontinuities are removed after reduce
the noise of the beat wavelength phase image. Thus, a 3D surface
profile of the grating is obtained.

8556-64, Poster Session

System calibration of road rut detection bylinear structured light and binocular vision
Shan Zhao, Yang Song, An-zhi He, Nanjing Univ. of Science andTechnology (China)

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Conference 8556:
Holography, Diffractive Optics, and Applications V
With the rapid development of national highway construction,
increasingly importance has been attached to the quality detection andmaintenance work on the highway surface all over the world. Rut is oneof the primary damages of the highway, and how to make the precise
and fast detection with the depth of pavement rutting is significant. This
paper presents a new method for road rut detection, which is based on
structured light measurement and binocular stereo-vision. Firstly, thelinear structured light is projected onto the road surface and two digital
images of surrounding scenery are acquired by two CCD cameras fromdifferent point of view. On this basis, three dimensional mathematicalmodel for linear structured light rut detection is established. And then,carry out research deeply on two key technologies including camera
calibration and linear structured light system calibration. By being
testified, the calibration methods for road rut detection are proved to befeasible. The advantage of this method is that the algorithm can reduceor even eliminate the effects which caused by the bumpy and pitchvehicles and the height is precise enough to meet the requirement.

8556-65, Poster Session

Study on effects of organic solventson proliferation of Hela cells by digitalholographyelectrochemical deposition, chemical vapor deposition, independent
fitted method, Lithography, mechanical stretching method, etc. Someof the fabricated super-hydrophobic surfaces are uneven and nottranslucent, which limits applications. Generally, the essential processes
in fabricating super-hydrophobic surface are the preparation of therough surface and subsequent treatment with low surface energy
materials.
In the paper, the micron-sized photoresist mask is fabricated via laserinterference lithography on the glass substrate and shifted to the glass
substrate by reactive ion etching. Then 20nm silver is coated on thesample by electron beam evaporation and subsequently heated by
the rapid annealing furnace to make the silver aggregation. At last, thesample is treated under the ethanol solution with 2 mM dodecanethiol.
The micro lattice and silver nanoparticles composite structures, which
is helpful for obtaining surfaces with super-hydrophobic ability. The
routes are simple and easy, which can be also used as a template forroll to roll imprinting technology and be easily realized in its large-scale
manufacture.

8556-68, Poster Session

Measurement of the optical fiber refractive
index profiling based on digital holography

Liting Ouyang, Dayong Wang, Yunxin Wang, Yizhuo Zhang,
Xinlong Wang, Beijing Univ. of Technology (China)

Duocheng Wang, Sujuan Huang, Zheng Chang, Tingyun Wang,
Shanghai Univ. (China)

In traditional Chinese medicine anticancer research, many medicinal
effective ingredients can only dissolve in higher polar organic solvents,
such as ethanol, DMSO and so on. However the organic solvents
may affect the accuracy of therapeutic efficacy evaluation. Therefor
the study on effects of organic solvents with different concentrations
on proliferation of Hela cells is very important in the research of
anticancer drugs and cell apoptosis. The digital holography is capableof giving phase-contrast images with high precision, which is suitable
for the imaging of transparent living cells. It can not only rule out
interference of the staining step on treatment outcome evaluation,but
also get the changes of surface topography quantitatively of cellproliferation inhibition.Based on the pre-magnification off-axis Fresnel
digital holography, an inverted digital holographic microscope isbuilt.Holograms are recorded by the CCD camera,and the numericalreconstruction and extraction process of phase images is completed in
the computer. Then phase-contrast images of Hela cells with different
concentrations of organic solvents are given. Based on the analysisof experimental results, Hela cells proliferation was significantly
inhibited by methanol, ethanol with concentrations ranged from 20%
to 100%,DMSO with concentrations more than 33%. In conclusion, thedigital holography is an optimized way for cell biology and traditional
Chinese medicine anticancer research, which has very high practicalvalue in the observing and detection of the changes of cell morphology.
It can also be used in testing the effectiveness of new drugs against
drug-resistant pathogens and cancer. It will contribute to the screeningof new drugs.

As development of optical technologies including fiber communicationand fiber sensor system, the role of optical fiber has become more andmore important. The characteristics of optical fiber are quite importantfor improving the performance in various applications. Expecially,
the refractive index of fiber is the most elementary aspect because it
describes how light propagates through the medium. Conventional
approaches to measure the refractive index of optical fiber havedrawbacks such as destruction and low efficiency.

8556-67, Poster Session

The fabrication of super-hydrophobic
surface on the glass
WeiPing Liu, Changsi Peng, Soochow Univ. (China)
The super-hydrophobic surface has captured the attention of many
materials scientists recently as there are potential applications in
defense, daily life and industrial areas. It exhibits unique performance
especially in the self-cleaning, reduced-friction, anti-corrosion,
prevention of snow disaster, anticoagulant, and oxidation, etc.
Generally, the micro-nano structures have great effects on the
wettability of the surface of a material. There are many methods tofabricate micro-nano structures on the surface, such as the sol-gel
method, template technology, soft printing method on the polymer,

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Digital holography is a powerful tool to measure the refractive
index because it takes the basic theories of classical holography
concerning 3-D information (complex amplitude distribution) of theobject wavefront. Besides, it also has advantages of digital processing
methods provided by computers. Based on optical fiber Mach-Zehnderinterferometer, a new measuring method using digital holography is
proposed in this paper. Unlike traditional holography, we use opticalfibers as light transmission arms of outputting object light and reference
light which simplifies the experimental set by reducing the opticalelements. The light emitting from the laser generator is seperated into
two light beams by a fiber coupler. One beam goes through the fiber
sample and the other becomes the refenrece light. Then several kindsof fiber samples such as multi-mode fiber , polarization-preserving
fiber and special fiber are tested and their holograms are recorded by
CCD. After the hologram is digitally processed by spectrum filtering,
the phase distrinbution can be reconstructed and extracted with goodquality. At last, the experimental results of refractive index profilingof fiber are given, which can be used to further research of fiber
characteristics.

8556-69, Poster Session

Factors of influencing the value of the W in
the bi-grating diffraction imaging equation
Weiping Zhang, Feng Zhu, Chunzhi Wang, Yanchun Gao, Lei
Liu, Guangxi Univ. (China)
The novel bi-grating diffraction imaging effect have been reported
for years. By this effect, a clear object image can be seen after thepolychromatic beam coming from object is diffracted twice by two
gratings.
This paper focuses on factors of influencing the value of W in the bigrating diffraction imaging equation. And W is approximately equal to1 when the bi-grating system is under the following ideal conditions.

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The two bi-gratings is parallel to each other, and the first one G1 is set
in a position where the incidence and diffraction angle of the object
beam are same, also the second one G2 is along the middle of the firstgrating’s diffraction beam of a certain diffraction order. But we foundthat the effect could also appear under some non-ideal conditions andthe value of W would change.
The values of W for the bi-grating system were studied under following
non-ideal conditions in experiments. G1 is set in a position where
the incidence angle of the object beam is larger or smaller than thediffraction angle, and G2 is respectively along optical paths for the red,green and blue lights of the first grating’s diffraction beam of a certain
diffraction order. The results of changes on W for these conditions are
given. It is of profound significance for understanding the effect deeply
and promoting the application of it.

8556-70, Poster Session

Electro-holography display using computer
generated hologram of 3D objects based on
projection spectra
Sujuan Huang, Duocheng Wang, Chao He, Shanghai Univ.
(China)Holography is able to provide the most authentic three-dimensional(3D) illusion to the human eye without the need for special viewing
devices. Computer generated holography has become an important
technique in 3D imaging, it can yield ideal 3D visual effects even forvirtual 3D objects. A new method of synthesizing computer-generated
hologram (CGH) of 3D objects from their projection images is proposed.
Numerical reconstruction of the hologram has been achieved. Electroholography display of the hologram can be implemented.
A series of projection images of 3D objects are recorded with
one-dimensional azimuth scanning. According to the principles ofparaboloid of revolution in 3D Fourier space and 3D central slice
theorem, spectra information of 3D objects can be gathered from theirprojection images. Because there is quantization error of horizontal andvertical directions, in order to make full use of projection spectra, thespectrum information of each projection image is extracted in double
circle even four circles form. Spectrum information obtained from all
projection images is used to fill the u-v plane. Then the wavefront
distribution of 3D object at the Fourier plane is achieved. The complex
matrix can be encoded efficiently into CGH of 3D objects basedon computer-generated holography using a conjugate-symmetricextension. Experimental results for numerical reconstruction of the CGH
at different distance validate the proposed methods and show its good
performance.

of polycarbonate, it will provide a better option for LED decorative
illumination under low cost.

8556-73, Poster Session

Theoretical analysis of volume moiré
tomography based on double orthogonal
gratings for real 3D flow fields diagnosis
Nan Sun, Yang Song, Jia Wang, Zhenhua Li, Anzhi He, Nanjing
Univ. of Science and Technology (China)
Moiré tomography has been considered as a powerful diagnostic toolfor complicated flow fields due to it is nonintrusive and instantaneous.
However, the normal moiré deflectometry, which could generate thepartial derivative of the projection data in one direction, cannot meetthe requirements of Volume Moiré Tomography (VMT) for real 3-D
reconstruction. Moreover, the partial derivative in two orthogonal
directions of the projection data is required for VMT. In this Letter, an
improved moiré deflected system based on double orthogonal gratings
is introduced to solve this problem. The proposed method could
obtain the first-order partial derivatives in two vertical directions of the
projection in one time. Then the second-order partial derivatives of
3-D Radon transformation of the test field can be obtained by merging
the data of these two directions. Theoretical analysis of this improved
moiré deflected is given in this letter. Comparing with the normal moiré
deflectometry based on double linear gratings, the proposed system ismore effective and easier to realize the multi-direction data acquisition.
Finally, this improved moiré deflected system is used for reconstruct thetemperature distribution of a simulated field.

8556-74, Poster Session

A novel 2D wavelength-time chaos code in
optical CDMA system
Qi Zhang, Xiangjun Xin, Yongjun Wang, Lijia Zhang, Chongxiu
Yu, Nan Meng, Houtian Wang, Beijing Univ. of Posts andTelecommunications (China)

8556-72, Poster Session

Chaos OCDMA is very potential in optical access due to its highcapacity and security. A novel wavelength-time chaos code for opticalcode division multiple access system is proposed and constructed fromone-dimensional chaos code based on map of Logistic equation. The
access performance based on the proposed chaos code is evaluatedby comparison with one-dimensional single wavelength chaos codeand one-dimensional WDM/chaos code according to capacity, spectral
efficiency and bit-error ratio. For two-dimensional wavelength-timechaos code, the usable wavelength number m is larger than its code
length L. When m is same, the capacity of two-dimensional wavelengthtime chaos code is always larger than that of WDM/chaos code andone-dimensional chaos code. Two-dimensional wavelength-time chaos
code always has a higher spectral efficiency than the corresponding
WDM/chaos code system when . The bit-error rate increases with thenumber of the users due to the increased level of inter-user interference.
For a fixed bit-error rate, the number of users using two-dimensional
chaos code is larger than that of one-dimensional chaos code.

Holographic two-dimensional photonic
crystal of LED decorative illumination

8556-25, Session 8

Electro-holographic reconstruction can be realized by using anelectronic addressing reflective liquid-crystal display (LCD) spatial
light modulator. The CGH from the computer is loaded onto the LCD.
By illuminating a reference light from a laser source to the LCD, theamplitude and phase information included in the CGH will be restored.
The 3D objects can be reconstructed in the distance due to thediffraction of the light modulated by the LCD.

Yidan Zheng, Fujian Normal Univ. (China)
The film of holographic two-dimensional photonic crystal is used forthe led illumination system. According to the decorative patterns, thestructure sizes of two-dimensional photonic crystal and relevant led
Luminaire have been reasonably designed. Then the master maskof two-dimensional photonic crystal is produced with the method ofmultiple-beam interference. With the experiment of LED illumination, theresults show that it is able to meet the expected decorative patterns of
LED illumination. While the master mask is used to copy optical coating

The formation of large scale reconstructed
images through the use of computer
generated holograms: colorization
Sumio Nakahara, Kyoji Matsushima, Kansai Univ. (Japan)
We propose and demonstrate a method which constructs large
size multicolor images in limited spaces, i.e. tunnels. The traffic

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Conference 8556:
Holography, Diffractive Optics, and Applications V
sign image, visibly the same size as the original physical sign, isreproduced using smaller size color holograms with R-,G-,B- laser.
Each 20cm square binary type of plane amplitude hologram is made bycomputer-generation method. Cross-talk images which appear in color
reproduction are separated by appropriate alignment of reconstruction
beams.

8556-26, Session 8

High-efficient design method of large
diffractive optical elements by vectorial field
analysis based on boundary element method(Invited Paper)
Jun-ichiro Sugisaka, Toyohiko Yatagai, Utsunomiya Univ.
(Japan)An efficient approach to design the structure of diffractive opticalelements (DOEs) is presented. Simulation of DOEs with conventional
vectorial diffraction methods requires considerably large calculation
resources, and cannot apply to DOEs with large apertures. We havedeveloped a multistep difference-field boundary element method. Thisis a vectorial diffraction method for non-periodic structures, and has anadvantage that the amount of memory consumption is almost free fromthe entire sizes of DOEs. This method firstly divides the groove patterns
on a DOE into a flat substrate and small projections on the surface. We
start with a field distribution for the flat substrate, and then iteratively
update the field distribution by adding the projections one by one. At
each step, the necessary discretization is only the dielectric boundaries
around the added projection, and can perform with very small memory
consumption. For designing a device structure, we add a projection
so that the updated field approaches to the desired one. Otherwise we
can repeat the step by changing the size or position of that projection.
After finding the optimal projection, we add the next projection. Whenthe all projections are added, we can obtain the device structure andthe diffracted wave simultaneously. As conventional methods, we do
not have to calculate the whole of huge structures many times withlarge-scale computers. The necessary memory for two-dimensional
structure is only around 20 MB, and our method is sufficient with adesktop computer to perform an accurate designing even including thepolarization characteristics.

8556-27, Session 8

A parameters study of the multi-plane
diffraction iterative algorithm for singlebeam phase retrieval
Yuanyuan Sun, Jinan Univ. (China); Zibang Zhang, Jinan Univ
(China); Jingang Zhong, Jinan Univ. (China)
Phase retrieval techniques have been used for the measurement of
3D objects. The phase of the transmitted or reflected light beam ismodulated by different characteristics of the object and reveals valuable
information. The multi-plane diffraction iterative algorithm is a methodof phase retrieval with single beam. Based on numerical phase-error
correction system, the method obtains the phase and amplitude ofa wave front using wave propagation equation with a sequence ofintensity patterns recorded at different planes. We study the threeparameters of this method, including the number of iterates andsampled planes and the distance from the first sampled plane to theobject, through simulations and experiments. In simulation, the retrieved
phase error is reduced with the increase of the number of iterates andsampled planes and the decrease of the distance from the first sampled
plane to the object. In practice, the increase of the number of iterates
and sampled planes reduces the retrieved phase error just in a certain
range. The error induced by the setup or the environment such as
aberrations, displacements, especially vertical displacements of planes
to record in motion and the spatial nonuniformity of the beam can be

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accumulated in the iterative processing, resulting in the deteriorationof the retrieved phase. Compromise has to be made for the balance
between accuracy and computation time. And the decrease of the
distance from the first sampled plane to the object is demonstrated to
improve the result in accord with the simulation.

8556-28, Session 8

Slanted volume holographic gratings design
based on rigorous coupled-wave analysis(Invited Paper)
Ting Li, Liangcai Cao, Tsinghua Univ. (China); Qingsheng He,
Guofan Jin, Tsinghua Unv. (China)
Volume holographic gratings are widely used because of the highefficiency and accurate orientation. Slant grating structure can enableoptical functions flexibly that cannot be easily reached in traditional
grating. So modeling of the slanted volume holographic gratingbased on rigorous coupled-wave analysis (RCWA) is necessary forpractical application. An oblique coordinate system related to thegrating fringes simplifies the mathematical analysis. The S-matrix
algorithm gives the mathematical results. Based on the periodicity,
RCWA can present all the diffraction orders including transmission andreflection. Compared with the traditional approximate scalar theory,
the RCWA for the modeling can analyze the angular selectivity and thediffraction efficiency accurately. Obviously, the diffraction details offer
all the grating features, thus making the design more accurate for the
dedicated grating.
In terms of the slanted vector modeling, many important factors, suchas the grating thickness, the relative index, the grating period and manyother structure parameters, have been taken into account. Connecting
all the impossible determinants, a transmission angle amplifier withthe diffraction efficiency close to 100% has been simulated. And thematching grating element has been reached successfully. In the angle
response, the highest efficiency approaches 100%, the first-order sidelobe peak is lower than 15% and the main-lobe bandwidth is less than
1 degree. At the same time, a narrow band filters with high reflection atresonance and high rejection has been also introduced.

8556-29, Session 8

Fast generation of hologram from range
camera images based on the sub-lines andholographic interpolation (Invited Paper)Peter W. M. Tsang, Wu Chao Situ, Kayton W. K. Cheung,
City Univ. of Hong Kong (Hong Kong, China); Ting-Chung
Poon, Virginia Polytechnic Institute and State Univ. (UnitedStates); Changhe Zhou, Shanghai Institute of Optics and Fine
Mechanics (China)
The intensity image and the depth images of a three-dimensional
object scene can be captured with a commodity range camera, andconverted into a Fresnel hologram. However, for some cameras, theimages are subject to radial distortion, and too small to be visible in
optical reconstruction. Moreover, the conventional hologram generation
process with numerical means is significant. In this paper, we present
a fast method to overcome the above-mentioned problems. First,
the intensity and the depth images are transformed to reduce theradial distortion. Next, the images are interpolated horizontally, andconverted into a sequence of sub-lines. Finally, the sub-lines are swiftly
converted into a Fresnel hologram through padding along the verticaldirection. The pair of interpolation process effectively increases thesize and visibility of the reconstructed image. Although our method canbe applied to different kinds of range cameras, we have selected the
Swissranger model as a showcase to demonstrate the feasibility of theapproach.

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Holography, Diffractive Optics, and Applications V

8556-30, Session 88556-32, Session 9

A new way to reconstruct the amplitude
distribution of coherent light source

Research on fabrication for nanostructureson the surface of GaN

Qiankun Gao, Graduate Univ of the Chinese Academy of
Sciences (China); Tuo Li, Liang Qiao, Yali Wang, Graduate
Univ. of the Chinese Academy of Sciences (China); Haifei
Li, Ordnance Repair Factory of Air Force (China); Yishi Shi,
Graduate Univ. of the Chinese Academy of Sciences (China)

Heng Zhang, Xiaohong Zhou, Zongbao Fang, Soochow Univ.
(China)In holographic projection, the actual coherent light source is different
from the theoretical light source. Therefore it reduces the system’s
output quality. This light source’s variation contains phase andamplitude parts. However, we consider the amplitude part is themain factor. Based on the assumption, a new iteration algorithm ispresented to reconstruct the amplitude distribution of the coherent lightsource. New diffraction optical elements can be designed by using thisreconstructed amplitude distribution, which will greatly improve theoutput image’s quality in holographic projection. Both simulation andexperimental results demonstrate the effectiveness of this method.

We demonstrate the fabrication of nanostructures on the GaN surface
using a GaN-on-Sapphire substrate, by using a nanosecond diodepumped solid-state laser (DPSSL wavelength 351nm and pulse duration
20 ns) as light sources. The laser is split into four interfering beams withtwo diffractive beam splitters and then interfered on the top surfaceof the sample. Composed by dot array, nanostructures are realized on
the GaN surface. The mechanism to form the dot array was analyzed
and it was found that the obtained nanostructures had a negative
shape of the interference pattern of four laser beams. The reflection
losses at the GaN interfaces are suppressed. The light extraction
efficiency is significantly improved for the nanostructured GaN layer.
This work provides a very practical approach to fabricate freestanding
nanostructures on the GaN-on-Sapphire substrate for further improving
the light extraction efficiency.

8556-31, Session 98556-33, Session 9

Dynamic holographic interferometry withmatrix LC modulator (Invited Paper)

3D measurement system with two detecting
channels using structured light

Vladimir Y. Venediktov, Saint Petersburg State Electrotechnical
Univ. (Russian Federation) and Saint Petersburg State Univ.
(Russian Federation); Sergey A. Pulkin, Saint-Petersburg State
Univ. (Russian Federation)

Shengbin Wei, Changhe Zhou, Shaoqing Wang, Shanghai
Institute of Optics and Fine Mechanics (China)

The method of holographic interferometry with increasing sensitivity
was applied for measurements of height of nano-steps (from 10
nm and higher) with standard uncertainty about 0.5 nm. The initial
microinterferogram with fringes of equal thickness is obtained inMichelson micro-interferometer with nano-step sample in one ofarms. That interferogram is registrated on CCD - camera and digital
inteferogram passed on matrix phase modulator with spatial resolution
30 lines/mm. The matrix phase modulator is placed on the exit of
two-beam Mach-Cender interferometer and illuminated by two planelaser beams. These two beams are diffracted on phase modulator,
are focused on and filtrated by diaphragm with holes in (+ 1-st ) and(- 1-st ) order of diffraction. The second digital interferogram with twice
increasing sensitivity is obtained on CCD - camera and so on. The
increasing of sensitivity is obtained because interference of waves
with complex conjugated phases. One can obtain the interference of
higher orders too if work with nonlinear interferogram. It is possible tomade any carrier fringe space frequency because usage of two planewaves in interferometer. The flatness less than l/100, topography ofsurfaces with height difference less than few nanometers is possible
to research with increased sensitivity too. Also we demonstrate thepossibilities of Rozhdestvenski Hook method with increasing sensitivity
for measuring of oscillator strengths (transition probabilities) for weakatomic transitions. It is important for future development of interference
spectroscopy because usual hook method has insufficient sensitivity
and allows us to measure oscillator strengths only for resonanttransitions from ground state or from metastable states for strongtransitions. It’s necessary to underline, that holographic interferometricmethods with increasing sensitivity are well known but here wedemonstrate the possibility of these methods with using of digitalinterferograms registered on matrix phase modulator.

In this paper we propose a 3D measurement system with two cameras
using structured light. The modulated light is projected on the object
by a projection lens. Two calibrated digital cameras are used to capture
the images of projected area on the object separately. According to
triangulation, the local 3D point cloud is obtained from the pair ofimages. The images are captured from different angles to cover thewhole profile of the object to obtain corresponding series of local 3D
point clouds. The series of local 3D point clouds are then connected
to generate the integrated 3D point clouds of the object according tosurface connection technique. The 3D point clouds can be exported as
the original data, or be rendered to generate a visual result.
We designed a special pattern of structured light to generate distinct
artificial corner points on the object. The system was used to measurea plaster statue of Apollo. More than 1.4 million of 3D point clouds
are obtained with a depth precision of less than 0.2mm. The systemwith the advantages of high measuring precision, compact structureand good robustness is highly attractive for applications in 3D
measurement, 3D display and so on.

8556-34, Session 9

The influence of squeezing ratio on thebirefringence characteristics of photonic
crystal fibers
Peng Song, Univ. of Jinan (China)
In recent years, the squeezed photonic crystal fiber with highbirefringence has attracted significant attention. The squeezed
photonic crystal fiber consists of elliptical air holes and squeezed
lattice in the cladding, which both can break the multi-fold rotational
symmetry of photonic crystal fibers and introduce high birefringence.
The author promoted a model to describe the squeezed degree ofphotonic crystal fibers and studied the influence of the squeezingon those photonic crystal fibers in previous work. We studied andanalyzed the influence of elliptical air holes or squeezed lattice on thebirefringence characteristics, respectively. However, the compounded
effect of elliptical air holes and squeezed lattice makes the influence ofbirefringence complicated, which is quite disadvantageous to analyze

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Conference 8556:
Holography, Diffractive Optics, and Applications V
and design the high birefringence photonic crystal fibers. In this paper,
a novel concept of squeezing ratio is introduced to describe thesqueezed degree of photonic crystal fiber with squeezed lattice andelliptical air holes in the cladding. We study and analyze the influenceof both of them on the birefringence characteristics based on the
supercell lattice method. Then a novel definition of squeezing ratio ispresented, which describes the compounded effect of elliptical air holes
and squeezed lattice on the birefringence characteristics. Studies showthat the birefringence simply varies with the squeezing ratio. So theconcept of squeezing ratio can be used effectively to design the highbirefringence photonic crystal fibers.

8556-35, Session 10

Three dimensional optical techniques using
Dammann gratings (Invited Paper)
Changhe Zhou, Shanghai Institute of Optics and Fine
Mechanics (China)
This paper summarized our work on three-dimensional opticaltechnologies using Dammann gratings, e.g., three-dimnensional
Dammann gratings, three dimensional imaging using a Dammann
grating, etc.. We developed three-dimensional Dammann grating
which can produce three-dimensional array with equal distance andequal intensity with a high-numerical-aperture lens. As we know, alens usually has a single focal point. Fresnel zone plate can generate
several axial focal points, but the intensity between them is unequal.
By introducing the concept of Dammann grating into the circular phase
plate, we invented Dammann zone plate(DZP) which can produce aseries of axial focal points with equal intensity. Combining DZP with aDammann grating, three-dimensional Dammann array will be generated,which is highly interesting for various applications.
We also built a three-dimensional measuring system using a Dammann
grating, with two cameras as the right eye and right eye, respectively.
We used a 64X64 Dammann grating for generation of a square arrayof light spots for parallel capturing the three-dimensional profile ofan object. The two cameras and the illuminating part are packaged
together. After scanning the object, its three-dimensional profile will beobtained. Experimental results demonstrated the effectiveness of thistechnique.

8556-36, Session 10

Beam splitters of metal-dielectric reflective
gratingAnduo Hu, Changhe Zhou, Hongchao Cao, Jun Wu, Jia Wei,
Shanghai Institute of Optics and Fine Mechanics (China)
Beam splitters are important optical components. In this paper,reflective 1x2 and 1x3 beam splitters based on metal-dielectric grating
are designed at wavelength of 1064 nm. Alumina, silver, alumina andfused silica films are coated on substrate in sequence from bottom totop. On the top fused silica film, grating with rectangular grooves are
etched. The alumina film immediately below the grating is a connecting
layer. The thickness of silver is 100 nm. Light is incident from air. In
order to realize high efficiency and uniformity, rigorous coupled-wave
analysis and simulated annealing algorithm are employed to search
the geometric parameters such as period, depth, duty cycle, thicknessof connecting layer and incident angle. For a 1x2 beam splitter, thedirection of the two diffraction orders is expected to be perpendicular.
The optimized 1x2 beam splitter is operated at angle of 37.4 degreeand can achieve diffraction efficiencies of 49.1% at the -1st order and48.9% at the 0th order. The optimized 1x3 beam splitter is operated
at angle of 6 degree. The diffraction efficiencies of the -1st, 0th and+1st orders are 32.8%, 32.3% and 33.0%, respectively. To guide thefabrication and operation of the beam splitters, the tolerance of grating
depth, duty cycle and angle are analyzed. The optimized beam splittersexhibit high efficiency and good uniformity, which should be useful inpractical applications.
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8556-37, Session 10

The focusing property of the VLS gratingwith different types of beams
Chunzhi Wang, Weiping Zhang, Yanchun Gao, Guangxi Univ.
(China)The varied line-space grating (VLS grating) has the ability of selffocusing and eliminating aberration, and it has been used widely inspectral measurement, fiber communication, synchrotron radiation
beam regulation, displacement sensing, and etc. Therefore, Study thediffraction characteristics of the VLS grating is of great significance.
When VLS grating is used in sensor, in some cases, it needs to be
known the focusing property of one VLS grating with different types ofincident lights. This article will study on it.
When the incident angle of the incident light changes, the focusing
position of diffracted light through VLS grating will be different. This
paper will study the differences. Mainly studies how the change of theincident angle of monochromatic plane wave impacts the focusing
properties of VLS gratings with same center spatial frequencies anddifferent frequency distributions. And impact of different wavelengthof monochrome plane wave. Besides the above work, we will study
the changes of the focusing properties of VLS gratings using sphericalwave instead of the plane wave and research the change law of the
focusing position of the VLS grating with different types of beams.

8556-38, Session 10

Absorption enhancement in thin-film solar
cell using grating structure
Jun Wu, Hongchao Cao, Anduo Hu, Jia Wei, Shanghai Instituteof Optics and Fine Mechanics (China)
The enhancement of absorption in thin-film amorphous silicon solar cellbased on guided mode resonance is theoretically investigated. This isachieved by patterning a grating with waveguide layer in the absorbing
layer and an antireflective layer on the top. The optimized grating
parameters are obtained by use of rigorous coupled-wave analysis andthe simulated annealing algorithm in the visible region. The absorption
at normal incidence is higher than 50% in the wavelength range 300660 nm, and the peak absorption is higher than 95% for both TE andTM polarization. We studied the angle dependence of the integrated
absorption spectrum in solar cell structures. The integrated absorption
for TM polarization is larger than TE polarization in the angular range of
0-88 degrees. In general, the averaged integrated absorption decreases
as the incident angle increases, but it is higher than 60% in the range
0-66 degrees. So it is very weakly dependent on the angle of incidence.
A physical understanding of enhanced absorption based on guided
mode resonance effect is presented. It is found that the effect caneffectively trap light in the absorber layer and enhance absorption in theactive layer. Double-groove grating structure is also discussed for thesake of reducing reflection and enhancing absorption. The designed
solar cells have high integrated absorption and are weakly dependent
on incident angle, which should be of highly practical significance.

8556-39, Session 11

Low-coherence holography with twospherical waves
Shaoqun Zeng, Britton Chance Ctr. for Biomedical Photonics(China)Low-coherence holography obtains three-dimensional information
without scanning and shows many potential applications. However,current method usually recorded holograms with plane wave as thereference wave. Here we show the holography with two spherical waves
exhibits special features over the one with plane waves. These features
will facilitate more application in the future.

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8556-40, Session 11

of Optics and Fine Mechanics (China)

Calibration and pre-compensation of directlaser writing system

We fabricate an optically addressed liquid crystal light valve based ona twisted nematic liquid crystal layer associated to a photoconductive
BSO layer. Based on the optical addressing of a continuous layer ofliquid crystal, the spatial transmittance distribution of 1053nm coherent
light through the light valve has a corresponding relationship with theintensity distribution of 470nm incoherent light projected onto thephotoconductive BSO layer. The AC voltage is added to both liquid
crystal layer (4.7microns thick) and photoconductive BSO layer (1mm
thick) through two transparent electrodes. Resistivity of the BSO layer
decreases when the intensity of 470nm address beam increases. Whenthe intensity of address beam projected onto the BSO layer changes,
the voltage on the liquid crystal layer changes accordingly, whichleads to different anisotropic birefringence of the liquid crystal layer.
So the BSO layer enables the intensity of 470nm address beam tolocally modulate the polarization of 1053nm read beam. A downstream
polarizer enables the polarization modulation to be manifested as anamplitude modulation. As a result, we can control spatial intensity
distribution of 1053nm read beam by controlling the intensity of
470nm address beam projected onto the light valve. In our experiment,by controlling the intensity of 470nm incoherent light with a LCOS
modulator, the spatial intensity distribution of 1053nm coherent lightthrough the light valve can be controlled correspondingly. Performance
characteristic of this light valve has been studied experimentlly toensure its ability of beam shaping for 1053nm coherent light.

Feng Zhu, Changhe Zhou, Jianyong Ma, Shanghai Institute of
Optics and Fine Mechanics (China)
The Direct Laser Writing (DLW) technique has become a wellestablished, flexible and multi-functional method of micro- andnano-technology. A DLW system, mainly containing blue light writing
module and red light autofocus module, is established and efficiently
applied for the fabrication of diffractive optical elements (DOEs). In
the DLW system, the stability of the writing beam is always a concern.
Although the autofocus module is employed to eliminate the influenceof the drifting focus point resulting from ambient vibration, the inherent
defocusing error still has a serious impact on the lithography accuracyof the DLW system. As the refractive index of the lithography objective
lens with a high numerical aperture (NA, 0.9) for blue light (405nm)
differs from that for the auto-focus red light (650nm), the focal planes of
the two beams will not coincide. Furthermore, the two beams can’t bemounted seriously parallel to the axis of the objective lens in practice.
The misalignment will impact the location of the focus point axially andlaterally. The above defocusing error is determined experimentally, andthen is pre-compensated, which improves the fabrication accuracy
dramatically. The relationship between defocusing amounts and line
widths of the stripes is obtained, which can be used for writing gratings
with different line widths. A 100?100 mm sized fused-silica gratingwith a period of 2 µm is obtained with the DLW system, and somemicroscope images are presented to show the effectiveness of theerror-eliminating methods.

8556-41, Session 11

Quantitative evaluation of spatial phaselight modulator characteristics in Fresnel
incoherent correlation holography
Man Tian Long, Yuhong Wan, Hao Chen, Zhuqing Jiang,
Dayong Wang, Shiquan Tao, Beijing Univ. of Technology (China)
Fresnel incoherent correlation holography (FINCH) is one of themethods for recording holograms of 3D samples under incoherent
illumination. The FINCH combines the theory of spatial self-coherence
and the technology of in-line phase-shift technology together toform a complex hologram. A spatial phase light modulator (SPLM)
plays an important role as dynamic diffraction optical elements (DOE)and phase shifter. The incoherent light originated from each object
point of 3D samples incidents to a SPLM and is split into two beams
with different curvature which are spatial self-coherence. A Fresnel
interference pattern including 3D information of the objects is capturedby an image detector. Three holograms with different phase-shift arerecorded sequentially for eliminating the zero-order and twin image,and then a complex valued hologram without bias is obtained bysuperposing the three holograms. The modulation characteristics of
SPLM and phase shift error in FINCH are investigated experimentallyin this paper. Phase modulation characteristics are measured when the
SPLM under coherent and narrow-bandwidth incoherent illumination
respectively base on digital holography technology and phase shift error
is analyzed in FINCH due to quasi monochromatic light illumination. The
effect of phase shift error on the quality of reconstructed image is also
investigated and some measures are proposed to reduce the phaseshift error.

8556-42, Session 11

An optically addressed liquid crystal lightvalve with high transmittanceDajie Huang, Wei Fan, Xuechun Li, Zunqi Lin, Shanghai InstituteDue to the strong interaction between liquid crystal molecules,
our device has the advantage of generating non pixellated spatialtransmittance. As a transmissive device, it has the advantage of hightransmittance(80%) and it can overcome the problem of black-matrix
effect compared with the traditional TFT(Thin Film Transistor) liquid
crystal modulator.

8556-43, Session 11

Tunable photonic structures from polymerliquid crystal composites
Irena Drevensek-Olenik, Univ. of Ljubljana (Slovenia)
Liquid crystals are soft materials with large anisotropy of physicalproperties. This combination provides that huge modifications of their
optical refractive index can be induced by relatively low external stimuli.
For that reason, liquid crystals are widely used in information displays(LCDs) and in various switching and sensing devices. Incorporationof liquid crystals in polymer structures and composites results in
microconfinment effects, which lead to several new interesting opticalfeatures and tuning capabilities. Investigations of tuning propertiesof two different types of polymer-LC composite materials, namely
holographic polymer-dispersed liquid crystals (HPDLCs) and lightsensitive liquid crystal elastomers (LS-LCEs), will be reviewed.
REFERENCES:
1. MILAVEC, Jerneja, DEVETAK, Miha, LI, Jianfeng, RUPP, R. A., YAO,
Baoli, DREVEN?EK OLENIK, Irena. Effect of structural modifications on
the switching voltage of a holographic polymer-dispersed liquid crystal
lattice. Journal of optics, 2010, vol. 12, no. 1, p. 015106-1-015106-8.
2. DEVETAK, Miha, MILAVEC, Jerneja, RUPP, R. A., YAO, B.,
DREVEN?EK OLENIK, Irena. Two-dimensional photonic lattices inpolymer-dispersed liquid crystal composites. J. Opt. A, Pure Appl. Opt.,
2009, vol. 11, p. 024020-1-02420-8.
3. GREGORC, Marko, LI, Hui, DOMENICI, Valentina, AMBRO?I?,
Gabriela, ?OPI?, Martin, DREVEN?EK OLENIK, Irena. Kinetics ofholographic recording and spontaneous erasure processes in lightsensitive liquid crystal elastomers. Materials (Basel), 2012, vol. 5, no. 5,
p. 741-753.
4. GREGORC, Marko, ZALAR, Bo?tjan, DOMENICI, Valentina,
AMBRO?I?, Gabriela, DREVEN?EK OLENIK, Irena, FALLY, Martin,?OPI?, Martin. Depth profile of optically recorded patterns in lightsensitive liquid-crystal elastomers. Phys. Rev. E, 2011, vol. 84, 3, p.
031707-1-031707-5,

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Conference 8556:
Holography, Diffractive Optics, and Applications V

8556-44, Session 11

Laser beam scanning using binary diffraction
holograms
Bosanta R. Boruah, Abhijit Das, Indian Institute of Technology
Guwahati (India)
Laser beam scanning is important in a number of applications such as
to detect events or information in a given surface or to induce physicalphenomena in a given surface. Laser beam scanning is also at thecore of a scanning optical microscope that is routinely used in numberof areas. One of the most commonly used beam scanner is a galvo
mirror scanner. However galvo mirror scanners suffer from limitations
such as short term repeatability and long term thermal drift. Hence forapplications requiring large number of scannings over a long durationof time, galvo mirror scanners are not appropriate. A binary hologram
displaying a reconfigurable grating profile can give rise to a diffracted
beam whose position on a plane is entirely dependent on the hologram
profile. Such beam positioning can offer an unlimited repeatability as
long as the grating pattern is described identically. Unfortunately such areconfigurable binary hologram, if used as a beam scanner, will not give
uniform step size of the diffracted beam for uniform increase in input
spatial frequency used to design the hologram. Further for pixellated
hologram planes there is no one-to-one relation between the beam
deflection angle and the input hologram frequency. In this paper we
propose a binary hologram based optical scanner. We show that it ispossible to theoretically suggest the precise location of the diffracted
beam from the input hologram frequency. Thus one can generate a
set of spatial frequencies of the grating pattern that can provide beam
deflection with equal step size. Preliminary experimental results clearly
demonstrate our proposed scheme of beam scanning.

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Optical Design and Testing V
Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8557 Optical Design and Testing V

8557-1, Session 1

8557-3, Session 1

Developing interface localized liquid
dielectrophoresis for optical applications(Invited Paper)

Optical modulation of polarization statebased on an etched single mode fiber with
azo-polymer overlay

Glen McHale, Northumbria Univ. (United Kingdom); Carl V.
Brown, Michael I. Newton, Gary G. Wells, Naresh Sampara,
Nottingham Trent Univ. (United Kingdom)

Weiwei Qiu, Xiujie Tian, Qijin Zhang, Bing Zhu, Univ. of Scienceand Technology of China (China)

Electrowetting charges the solid-liquid interface to change thecontact area of a droplet of a conducting liquid. It is a powerful
technique used to create variable focus liquid lenses, electronic
paper and other devices, but it depends upon ions within the liquid.
Liquid dielectrophoresis (LDEP) is a bulk force acting on the dipoles
throughout a dielectric liquid and is not normally considered to be a
localized effect acting at the interface between the liquid and a solid orother fluid. In this work, we show theoretically how non-uniform electricfields generated by interdigitated electrodes can effectively convert
LDEP into an interface localized form. We show that for droplets ofsufficient thickness, the change in the cosine of the contact angle is
proportional to the square of the applied voltage and so obeys a similar
equation to that for electrowetting – this we call dielectrowetting.
However, a major difference to electrowetting is that the strength of theeffect is controlled by the electrode spacing and the liquid permittivity
rather than the properties of an insulator in a sandwich structure.
Experimentally, we show that that this dielectrowetting equation
accurately describes the contact angle of a droplet of oil viewed acrossparallel interdigitated electrodes. Importantly, the induced spreading
can be complete, such that contact angle saturation does not occur.
We then show that for thin films, LDEP can shape the liquid-air interface
creating a spatially periodic wrinkle and that such a wrinkle can be used
to create a voltage programmable phase diffraction grating.

8557-2, Session 1

Wafer-level micro-optics: trends inmanufacturing, testing, packaging, andapplications
Reinhard Voelkel, Li Gong, Jürgen Rieck, Dayu Zheng, SUSS
MicroOptics SA (Switzerland)
Micro-optics is an indispensable key enabling technology (KET) for
many products and applications today. Probably the most prestigious
examples are the diffractive light shaping elements used in high-end
DUV lithography steppers. Highly-efficient refractive and diffractive
micro-optical elements are used for precise beam and pupil shaping.
Micro-optics had a major impact on the reduction of aberrations
and diffraction effects in projection lithography, allowing a resolution
enhancement from 250 nm to 45 nm within the last decade. Microoptics also plays a decisive role in medical devices (endoscopes,
ophthalmology), in all laser-based devices and fiber communication
networks, bringing high-speed internet to our homes. Even our modern
smart phones contain a variety of micro-optical elements. For example,
LED flash light shaping elements, the secondary camera, ambient lightand proximity sensors.
Wherever light is involved, micro-optics offers the chance to further
miniaturize a device, to improve its performance, or to reduce
manufacturing and packaging costs. Wafer-scale micro-optics
fabrication is based on technology established by semiconductor
industry. Thousands of components are fabricated in parallel on awafer. This review paper recapitulates major steps and inventions inwafer-scale micro-optics technology. We report on the state of the art inwafer-based manufacturing, testing, packaging and present examples
and applications for micro-optical components and systems.

A large modulating range of polarization state at 1550nm is achievedby using an etched single mode fiber (SMF) overlaid with azo-polymer.
Most cladding of the SMF is etched off by hydrofluoric acid (HF) to
access evanescent field, and then the azo-polymer is used as coating
layer for the etched fiber. With irradiation of polarized light, the photoreorientation of azo-polymer occurs, causing the birefringence inthe fiber. This optically induced birefringence results in the changeof polarization state which is continuously recorded on the Poincare
sphere, making the state of polarization (SOP) tunable by the irradiationof 365nm polarized light. By precisely controlling the refractive indicesof the azo-polymer which are 1.4489, 1.4479 in two orthogonal
directions, the SOP of propagating light in the etched fiber can bechanged significantly by the irradiation of 365nm light with different
polarization directions. The SOP changes from right-handed ellipticalpolarization to left-handed elliptical polarization, also linear polarizationis achieved. The trajectory of the SOP can also be recovered to theinitial polarization state when irradiated by unpolarized light. The phaseshift of the propagating light varies from 28.8 degree to 143.0 degree
and the ellipticity varies from 16.2 degree to 55.6 degree during theirradiation. Our experimental results show a simple method of achieving
large modulation of polarization state of propagating light by opticalcontrol.

8557-77, Session 1

Fabrication method of artificial compoundeye
Lifang Shi, Axiu Cao, Yan Liu, Institute of Optics and Electronics(China); Yutang Ye, Univ. of Electronic Science and Technology
of China (China); Qiling Deng, Institute of Optics and Electronics(China); Chunlei Du, Chongqing Institute of Green and Intelligent
Technology (China)
Optical imaging and detecting are extensively used in biomedical,
industrial, and military applications, and there is a continuing trend in
the performance improvement of such systems. However, traditional
imaging system suffers narrow field of view (FOV). To address thisissue, artificial compound eyes has attracted a great deal of researchinterest, which comprise thousands of integrated optical units calledommatidiums spherically arranged along a curvilinear surface sothat each unit points in a different direction. The omnidirectionallyarranged ommatidium collects incident light with a narrow range ofangular acceptance and independently contributes to the capabilityof wide field-of-view (FOV) detection. For practical implementationsof compound eyes with wide FOV, the requirement of curvaturecompatible fabrication schemes is evident. In this work, a method used
to fabricate artificial compound eye is presented, where microlens
are used as ommatidium. Regular micro-fabrication is adopted to
manufacture the planer microlens array pattern. Soft-lithography is used
to manufacture the deformed elastomer membrane to obtain opposite
concave microlens patterns. 3D Polymer replication is used to transfer
the patterns onto the hemispherical dome substrate. Experiments werecarried out and an artificial compound eye contain over 20 thousands
ommatidiums was fabricated. No expensive equipment and materials
are needed in the fabrication process. The 3D polymer fabrication
fabrication method presented in this work has potential for a broad

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Conference 8557:
Optical Design and Testing V
range of optical applications, such as data storage and readout,
medical diagnostics, surveillance imaging, and light-field photography.

8557-5, Session 2

Aberration retrieval using through focus
intensity measurements (Invited Paper)
Silvania F. Pereira, Technische Univ. Delft (Netherlands)
The increased interest in qualification methods for lenses may be
explained from a number of factors: lens aberrations are known to havean important contribution to linewidth or image displacement in opticalprojection lithography and it leads to serious limitations in the quality ofimages in microscopy. Several methods to measure lens aberrations arecommercially available based on interferometry, wavefront sensing, andresist printing.
Here, we show an easy assessment tool that would allow rapid controlof the quality of these lenses. The measurement is based in obtaining
the through-focus intensity distribution of the point spread function of
the test lens.
We use two approaches to retrieve the aberrations: a semi-analytical
approach based on the solution of the Debye integral using the
Extended Nijboer Zernike theory and another approach based oncorrelation between the through focus images. Experimental results thatvalidate the theoretical expectations are presented.

8557-6, Session 2

Aspheric optics testing with the SCOTS: areflection deflectometry approach (Invited
Paper)
Peng Su, James H. Burge, College of Optical Sciences, The
Univ. of Arizona (United States)
A software configurable optical test system (SCOTS) based on thefringe reflection or phase measuring deflectometry method wasdeveloped for rapidly, robustly, and accurately measuring large, highly
aspheric optics.
In its simplest configuration, all that is needed to perform the test is a
laptop computer with a built-in camera. The laptop illuminates the test
surface with a light pattern on the LCD screen and uses the reflected
image to determine the surface gradients.
The SCOTS acts as a Hartmann test in reverse. To obtain large dynamic
range, the CCD detector of the Hartmann test is replaced with a flat
display and sending light backward, while a pinhole camera takes place
the position of the point source in the Hartmann setup. The camera is
conjugated with the test mirror. Each valid pixel samples certain region
on the mirror, so the classical Hartmann screen is not needed.
We have applied SCOTS to measure many different aspheric opticalsystem such as solar collectors, 8.4m diameter primary mirror segment
for Giant Magellan telescope, meter level highly aspheric mirrors ofthe Hobby Eberly Telescope wide field corrector, X-ray optics, and a
350mm convex aspheric mirror. The results show that the SCOTS has aperformance comparable with interferometric methods.

susceptible to mechanical vibrations. One of the most commonlyused wavefront sensor in such applications is the Shack-Hartmann
wavefront sensor (SHWS). It comprises an array of micro lenses which
focuses the various zones of an incident wavefront on the detector
plane of a digital camera. The incident wavefront profile is measured
from the focal spot shifts corresponding to each tiny lens. The speedof such a wavefront sensor depends on the frame rate of the digital
camera. Recently we showed that the array of tiny lenses of the SHWS
can be replaced by an array of gratings followed by a focusing lens.
One advantage of such an arrangement is that the array of focal spots
can have reduced number of rows. In this paper we implement such a
grating array based zonal wavefront sensor using a ferro electric spatial
light modulator (FLCSLM). We show that the gratings in the sensor canbe configured in such a way that the focal spots form just one row in
the ideal case (i.e. the incident wavefront is plane). We further show that
this gives rise to reduced number of effective rows of the digital camera
leading to extremely high frame rate. We present here proof-of-concept
experimental results using the proposed zonal wavefront sensor setup.

8557-8, Session 2

Test of diffractive optical element for DUVlithography system using visible laser
Zhonghua Hu, Jing Zhu, Baoxi Yang, Yanfen Xiao, Aijun Zeng,
Huijie Huang, Shanghai Institute of Optics and Fine Mechanics,
Chinese Academy of Sciences (China)
Diffractive optical element (DOE) is widely used to generate various
illumination modes in deep ultraviolet (DUV) lithography system. Testing
optical performance of DOE under the working wavelength of DUVlaser is accurate but complex. Testing DOE using a visible laser makethe process more convenient. Additionally, optical alignment of DUVlithography system under assembly is usually carried out with a visible
laser, it is more helpful to test the optical performance of DOE in thevisible light conditions.
The farfield diffractive pattern distribution is theoretically analyzed
with the scalar diffraction theory when the DOE designed for DUVlithography system is tested with a visible laser. The analysis resultshows the diffractive pattern distribution of the DOE is enlarged
proportionally with a zero-order spike in its center under visible laser
condition. Using Matlab program, the diffractive pattern distribution of
the DOE is simulated. The simulation result agrees with the theoreticalanalysis result and indicate the feasibility of the test method.
For test, a He-Ne laser passes through the DOE under test and a fourierlens, the farfield diffractive pattern is generated on a screen. The DOE
and the screen is located at the front and back focal planes of a fourierlens, respectively. By image processing, the azimuth, the pole angle andthe pole balance can be obtained.
In experiments, the DOE was tested under the working wavelengthof 193nm and the results were used as the reference values. Thenthe DOE was tested under a He-Ne laser and its farfield diffraction
pattern was analyzed to calculate its parameters. The experimental
results coincide with the reference values. The usefullness of method isverified.

8557-9, Session 2

High-speed zonal wavefront sensing

Wave-front aberrations analysis by Zernike
polynomials based on the annular subaperture stitching system

Bosanta R. Boruah, Indian Institute of Technology Guwahati(India); Biswajit Pathak, Abhijit Das, IIT Guwahati (India)

Lei Duan, Mei Hui, Cheng Gong, Yuejin Zhao, Beijing Institute ofTechnology (China)High speed wavefront sensing is important in applications such asreal time optical profile analysis, analysis of fluid dynamics, andophthalmology. Wavefront sensor can also be used for surface profilingand high frame rate of the sensor will cause the system to be less

Large aperture aspheric optical elements with their excellent opticalproperties, have played a significant role in areas such as aerospaceand military imaging systems. Annular sub-aperture stitching method
was developed for testing large-aperture aspheric surfaces without

8557-7, Session 2

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Optical Design and Testing V
using of any compensating element for measurement. It is necessary
to correct measurement of aspheric optical aberrations and create
mathematical description to describe wave-front aberrations. This
paper presents a method that uses Zernike polynomials to describe thewave-front aberrations of full wave-front and reconstructed wave-front
by annular sub-aperture stitching algorithm, in order to prove that theannular sub-aperture stitching method can meet the requirement forhigh precision and effectiveness.

Kenzo Nishio, Shogo Ura, Toshihiro Kubota, Kyoto Institute ofTechnology (Japan); Osamu Matoba, Kobe Univ. (Japan)

8557-11, Session 3

Parallel phase-shifting digital holography is a technique capable of highprecision and three-dimensional (3-D) measurement of objects with asingle-shot exposure In this technique, a single hologram containing
multiple holograms required for phase-shifting digital holography is
optically generated by using space-division multiplexing of holograms.
The single hologram is recorded by using an image sensor. The multiple
holograms are numerically generated by interpolating the recorded
hologram by using a computer. The complex amplitudes of the objects
are numerically reconstructed by use of the scheme of phase-shifting
digital holography. Not only phase images but also 3-D images of theobjects are obtained. We constructed a system of the parallel phaseshifting digital holography consisting of a Mach-Zehnder interferometerand a high-speed camera. The high-speed camera is capable ofdetecting polarization of light wave pixel-by-pixel. This camera canrecord holograms consisting of 1024?1024 pixels, 512?512 pixels,
128?128 pixels, and 64?64 pixels, at the rate of 7,000 frames per
second (fps), 15,000 fps, 150,000 fps, and 300,000 fps, respectively.
Motion picture of 3-D image of two vibrating elastic bands located at
different depth was demonstrated at 180,000 fps by the system. Motion
picture of phase image of flow of compressed transparent gas sprayedfrom a nozzle was demonstrated at 180,000 fps. Strange dynamics inthe flow was observed in the motion picture of phase image. Also a
motion picture of phase image of dynamic change of air induced by afocused femtosecond light pulse in air was recorded at 262,500 fps.

Recent progress on digital holography for 3D
display (Invited Paper)

8557-14, Session 3

Zernike polynomials form a complete set of modes that are orthogonalover a circular or an annular pupil. Different modes of wave aberrations
with a circular or an annular pupil are accurately described by different
weighted sum of Zernike polynomials, and the orthogonal set of Zernike
polynomials is suitable to describe wave aberration functions and data
fitting of experimental measurements for the annular sub-aperture
stitching system. Here, the analysis is proven by computer emulation.
Simulation are given to demonstrate to the original full-aperture wavefront of the surface by setting up Zernike coefficient in circular region.
According to the division of the sub-aperture, different annular regions
wave-front surfaces are acquired by a given coefficient of annular
Zernike polynomials. The full-aperture surface are reconstructedby stitching algorithm. At the same time, the imaging quality of theaspheric optical element can be contrasted. The stitching result shows
good agreement with the full-aperture result.

Hiroshi Yoshikawa, Takeshi Yamaguchi, Nihon Univ. (Japan)
We have been investigating on digital holography for 3D display,
particularly fast calculation of the computer-generated hologram (CGH).
The hologram is known as the ultimate 3D display because it has all
three-dimensional information and the reconstructed image of thehologram provides the natural spatial effect. However, required pixel
number for the practical 3D hologram is much higher than that for 2D
images. Therefore, fast generation of CGH is quite important. This talkreviews recent progress on CGH, mainly done by the speaker’s group.
In addition, output methods such as holographic fringe printers andholographic video displays are also reviewed.

8557-12, Session 3

Three-dimensional display based on phasemodulation (Invited Paper)
Osamu Matoba, Kobe Univ. (Japan)
Holographic 3D display is known as an ideal 3D display. However,holographic reconstruction creates unwanted reconstruction such as
DC term and conjugate of the object wave. These unwanted terms
reduces spatial frequency contents of reconstructed 3D object andviewing zone in a 3D display. In this presentation, 3D display based on
the modulation of phase distribution of object wave is briefly reviewed.
The phase distribution to generate 3D objects in air is obtained bydigital holography for real objects or by numerical propagation fromcomputer graphics data for virtual objects. Experimental demonstration
using 2K1K phase mode spatial light modulator (pSLM) is presented.
We also presented a method for achieving wide viewing angle using
single pSLM.

8557-13, Session 3

Digitization and visualization of virtual
cultural heritage
Ameng Li, Xiang Peng, Dong He, Hailong Chen, Xiaoli Liu,
Shenzhen Univ. (China); Qinping Zhao, Aimin Hao, BeiHang
Univ. (China); Xinghua Qu, Tianjin Univ. (China); Kaibing Xiang,
ESUN Co., Ltd. (China)
In recent years, virtual cultural heritage generated by optics andcomputer graphics methods has become an active research subject
that has drawn much attention and interest from communities of opticalengineering, computer science and cultural heritage around the world.
In this talk, we are going to briefly 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 can see that the technology of 3D scanning and interaction withhigh quality 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 designedwith 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 turntablein our proposed platform architecture. With this dedicated design, weare able to digitize complete 3D virtual heritage with complex geometry
and topology while the 3D scanning pipeline, including the acquisition
and registration of multiple range images can be implemented in a fully
automatic fashion. Furthermore, the texture mapping and blending arealso 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 andinteraction software are described in this presentation. Furthermore,some of experiment results for digitization and visualization of virtual
cultural heritage are shown to demonstrate the effectiveness ofproposed platform.

Parallel phase-shifting digital holographysystem using a high-speed camera (Invited
Paper)
Yasuhiro Awatsuji, Takashi Kakue, Tatsuki Tahara, Peng Xia,
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Conference 8557:
Optical Design and Testing V

8557-15, Session 38557-17, Session 4

Basic problems in 3D real-time holographic
display

The behavior of branch points in laser
propagation through atmosphere

Juan Liu, Jia Jia, Beijing Institute of Technology (China)

Xiaolu Ge, Anhui Institute of Optics and Fine Mechanics,
Chinese Acad (China) and Shandong Univ. of Technology(China); Chengyu Fan, Xiaoxing Feng, Anhui Institute of Optics
and Fine Mechanics (China); Chengfeng Li, Xiaojuan Liu, Liping
Guo, Gongxiang Wei, Shandong Univ. of Technology (China)

A holographic display can reconstructe the whole optical wave fieldof a three-dimensional (3D) scene, and it is known as the only 3D
display technique that can produce all the depth cues. The commerical
pixelated spatial light modulator (SLM) is employed in a typical 3D
display system. However, the zero-order intensity exists in the image
plane because of the pixelated structure of a phase only SLM, which
is a typical problem when using a commercial SLM for holographic
projection of arbitrary light patterns. To achieve the real time 3D
holographic display, there are still two main problems hindering thereal time applications of state-of-art holographic 3D projection: oneis the enormous computational time, and the other is the limited sizeand viewing zone of the reconstructed 3D optical image due to thelimitations of the total size and its pixel pitch of the SLM. As is wellknown, higher resolution and smaller pixel pitch of the SLM on which
the hologram is loaded will lead to a larger viewing zone and a bigger
size of the 3D reconstructed image. Here a technique is proposed
theoretically and verified experimentally to eliminate a zero-orderbeam caused by a pixelated phase-only spatial light modulator (SLM)
for holographic projection; we propose a simple technique to enlarge
the reconstructed three-dimensional (3D) optical image and shorten
the reconstructed distance simultaneously in real time holographic
projection using a conventional lens or concave reflecting mirror basedon the optical reversibility theorem.
References:
1. Jia Jia, Yongtian Wang, Juan Liu, Xin Li and Jinghui Xie,
“Magnification of three-dimensional optical image without distortion in
dynamic holographic projection”, Opt. Eng. 50, 115801 (Oct 27, 2011);
doi:10.1117/1.3654163.
2. Dongdong Weng, Nan Zhu, Yongtian Wang, Jinghui Xie, Juan
Liu*,” Experimental verification of optical image encryption based oninterference”, Optics Communications 284 (2011) 2485–2487.
3. Nan Zhu, Yongtian Wang, Juan Liu, Jinghui Xie, “Holographic
projection based on interference and analytical algorithm”, Optics
Communications 283 (2010) pp. 4969-4971.
4. Hao Zhang, Jinghui Xie, Juan Liu, and Yongtian Wang?”Eliminationof a zero-order beam induced by a pixelated spatial light modulator forholographic projection” Applied Optics Vol. 48, No. 30, 5834-5841, 20
October 2009.
5. Hao Zhang, JinghuiXie, Juan Liu, and Yongtian Wang, “Opticalreconstruction of 3D images by use of pure-phase computer-generated
holograms”, Chinese Optics Letters, Vol. 7, No. 12, 1-3, December 10,
2009.

8557-16, Session 4

Super-resolving spots for high momentum
transfer sub-wavelength scatterometry andimaging (Invited Paper)
H. Paul Urbach, Technische Univ. Delft (Netherlands)
By shaping the field in the entrance pupil of a high NA lens, very
special focused fields can be obtained. For example, fields which, fora given focused power , give the maximum electric energy density infocus or the maximum force in a given direction on a small particle in
the focal point. The corresponding pupil fields can in some cases be
obtained in closed forms. In other cases an expansion of the pupil fieldin Zernike polynomials is convenient. To realize these focused fields,
the polarization, amplitude and phase of the pupil fields must be madeposition dependent. This can be achieved by spatial light modulators.
We shall discuss an number of examples of special focused fields.
Furthermore we will discuss the application of focused fields in subwavelength scatterometry and high resolution imaging.
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When branch points are present in laser beam wave-front during the
propagation in turbulence, the adaptive optics system for atmosphereturbulence compensation will be degraded greatly. The theory of
branch-point detection and phase reconstruction is introduced.
Numerical experiments are carried out about the temporal and spatial
variation of branch points by four-dimension code of laser propagating
in atmosphere. The act of branch points’ creating and annihilating
is emulated when the light wave propagating in atmosphere. The
evolvement of branch points in some propagating range withtime is emulated, too. In the adaptive optics system, the phaseof compensating main laser is acquired from the distorted field of
beacon laser, so the behavior of branch points in the distorted opticalfield is simulated when the main laser and beacon laser propagate
in the atmosphere with opposite direction at the same time. These
computational results indicate that branch points are moving at the
movement of a light wave in the space, and they create and annihilate
in pairs. The position of branch points in distorted optical field varies
with time when the propagating range is fixed. When the condition oflaser beam propagating in atmosphere is fixed, the ensemble averageof branch points can be definite at the fixed propagating range. The
beacon laser produces more branch points than main laser when they
propagate in the atmosphere with opposite direction at the same time.
So when the branch points in turbulence-distorted optical field areconsidered, the compensating power of adaptive optics can becomemuch better when the beacon wavelength chosen slightly longer than
the wavelength of main laser. The work could provide a reference forfurther study of laser propagation through atmosphere and adaptive
optics system.

8557-18, Session 4

Implementation of controlling the divergenceangle utilizing liquid crystal optical phasedarray
Feng Xiao, Lingjiang Kong, Univ. of Electronic Science andTechnology of China (China)
Laser radar has the disadvantage in target detection because of its
extreme narrow beam. The efficiency of the laser radar system fordetection and tracking will be greatly increased if it can rapidly andaccurately control the size of divergence angle of the transmitted laser
beam. This paper analyses the propagation properties of the Gaussian
beam and the transform function of a lens, then obtain the method tochange the size of the divergence angle of a Gaussian beam by using alens with proper focal length. Then an implementation of tunable liquid
crystal lens is proposed in this article based on the principle of opticalphased array technology and the electro-optic characteristic of theliquid crystal. Theoretic analysis of the feasibility is made and a liquidlens is fabricated. The device has 1920 electrodes and an aperturesize of 10mm. It is driven by a voltage of 5V and each electrode canbe controlled independently by AC square-wave voltage. Simulation
has been made to demonstrate the liquid lens can vary the length
at the range of 0.4m to 10m continuously. A method is also been
proposed that uses this liquid crystal phased array tunable lens tomodulate the wavefront of an incident Gaussian beam and change thesize of divergence angle continuously and rapidly without changing
the structure of the device. Experiment has also been done to certify
the liquid crystal lens has the capacity to control the divergence of anincident light by varying the focal length.

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8557-19, Session 58557-21, Session 5

New approach to cost-based tolerancing(Invited Paper)

Description and implementation studies onfield dependent wavefront aberration

Akira Yabe, Independent Consultant (Germany)

Luwei Zhang, Zhaofeng Cen, Xiaotong Li, Zhejiang Univ. (China)

The tolerances are given to keep the performance criteria within theacceptable values in the manufactured lenses. If the tolerances and theperformance criteria are given, the yield of the manufacturing can be
estimated with the Monte Carlo simulation. The tolerance determines
the manufacturing cost. The manufacturing cost should be as low as
possible. The cost-based tolerancing is to determine the tolerances
accounting for the manufacturing cost. The typical formulation of thecost-based tolerancing is to minimize the cost under the target yield or
to maximize the yield under the target cost.

Zernike polynomials has been widely used to fitting lens surface
figure error and the wavefront aberration of optical systems ,for its
orthogonality in the unit circle and its corresponding relationships with
optical aberrations. Because the current extensively used Zernike
polynomials is just a function of the aperture ,without consideration of
the field factor , it can only represent single field wavefront aberration.
This is imcomplete for the description of the wavefront aberration,
especially for lithographic lens with a large field and high imaging
quality.Thus, considering the field factor in the description of wavefront
aberration becomes very necessary. This paper presents a convenientand practical method to fit the full field wavefront aberration. A
rotationally symmetric optical system has been taken as an example,
in the scope of normalized full field, selecting field points close to the
Chebyshev polynomial zero points as the interpolation nodes, andapplying the Chebyshev polynomial to the fitting of Zernike coefficientsof different fields. Meanwhile, taking the Chebyshev polynomial fittingorder’s influence on the fitting accuracy into account, this paper gives
the criterion to determine the best fitting order for different opticalsystems by comparing and analysing the fitting results of different fittingorder. The results show that the fitting method used in this paper is ofhigh accuracy, and the fitting results is very important for the analysis offull field wavefront aberration.

This optimization problem looks complicated and time-consumingwhen the yield is viewed as a function of the tolerances. The global
optimization seems to be necessary, because there are many local
minima in the tolerance space. If the discrete values of the tolerances
are possible, the problem looks like a combinatorial one.
The number of the combination grows exponentially to the number of
the tolerance parameters. The author found the problem is dramaticallysimplified if the the variances or averages of the critical performance
criteria are used as the independent variables of the optimization. The
optimal tolerance set can be found with a few trials of the Monte Carlosimulation.
In the cost model, the tolerances may be continous or discrete. It will
be shown that, for the discrete cost model where the choice from 2 or 3
values is possible for a tolerance parameter, the cost optimization canbe simplified with the linear programing.
In an example, the curvature, surface separation, refractive index, andAbbe number will be toleranced. The tolerancing of the refractive indexand Abbe number will be discussed in detail.
Reference:“Rapid optimization of cost-based tolerancing”, Applied Optics, 51,
855-860 (2012)8557-20, Session 5

Thermal control design of a multi-channel
scanning imagery radiometer (Invited Paper)
Jiang Shichen, Bingting Hu, Xu Tao, Shanghai Institute ofSatellite Engineering (China); Ganquan Wang, Shanghai Instituteof Technical Physics (China)
The multi-channel scanning imagery radiometer is one of the main
payloads of a geostationary earth orbit satellite, which can observe
multi spectrum from earth. The radiometer will endure complicated heat
flux environment in orbit, and effective thermal design for the instrument
is required in order to ensure high quality scanning image.
According to the geosynchronous orbit characteristics andconfiguration of radiometer, thermal design features are summarized
to control the temperature of radiometer by means of heat dissipation,
thermal insulation design, isothermal design and active heaters’ control.
Detailed thermal control design was showed in this paper.
Radiometer thermal model is developed using the NEVEDA andSINDA/G software. Heat flux calculation and temperature calculation
were performed for all typical orbital cases, and the numericaltemperature results of the radiometer are showed all within theacceptable range for all typical orbital cases. The numerical results
verified the validity of the thermal control design.

8557-22, Session 5

Simulation analysis of space remote sensing
image quality degradation induced bysatellite platform vibration
Feng Yang, Xiaofang Zhang, Yu Huang, Weiwei Hao, Baiwei
Guo, Beijing Institute of Technology (China)
Satellite platform vibration causes the image quality to be degraded,
it is necessary to study its influence on image quality. The formsof Satellite platform vibration consist of linear vibration, sinusoidal
vibration and random vibration. Based on Matlab & Zemax, thesimulation system has been developed for simulating impact caused bysatellite platform vibration on image quality. Dynamic Data Exchange
is used for the communication between Matlab and Zemax. The dataof sinusoidal vibration are produced by sinusoidal curve with specificamplitude and frequency. The data of random vibration are obtained by
combining sinusoidal signals with 10Hz, 100Hz and 200Hz’s frequency,
100, 12, 1.9’s amplitude and white noise with zero mean value. Satellite
platform vibration data which produced by Matlab are added to theoptical system, and its point spread function can be obtained byZemax. Blurred image can be gained by making the convolution of
PSF and the original image. The definition of the original image and theblurred image are evaluated by using average gradient values of image
gray. The impact caused by the sine and random vibration of six DOFs
on the image quality are respectively simulated. The simulation result
reveal that the decenter of X-, Y-, Z- direction and the tilt of Z-direction
have a little effect on image quality, while the tilt of X-, Y- direction
make image quality seriously degraded. Thus, it can be concluded that
correcting the error of satellite platform vibration by FSM is a viable andeffective way.

8557-23, Session 5

A realization method of full-field point
spread function
Hongmei Luo, Zhaofeng Cen, Xiaotong Li, Zhejiang Univ.
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Conference 8557:
Optical Design and Testing V
Point spread function (PSF) describes the intensity of the diffraction
image formed by the optical system for a point source in the field. PSF
is frequently used in image quality evaluation of optical system, image
restoring and image simulation. The PSF of an optical system varies
with the position of the point source and such variance cannot be
negligible particularly with the increasing degree of complication of the
optical system. Therefore it becomes advantageous to know how eachelement in the PSF matrix depends on the field.
This paper proposes a realization method of full-field PSF. Firstly thedata of several field points of the PSF are obtained by using the opticaldesign software, then the expression for the field dependence of eachelement in the PSF matrix is gotten by polynomial fitting, thus the PSF
matrix of any field, i.e. the full-field PSF is realized.
To verify this method, we choose a real optical system in this context,
and compare the PSF adopting the method mentioned above with thatobtained in optical design software by ray tracing. The comparison
shows that the full-field PSF method is able to obtain the PSF of any
desired field in less time and with relatively high accuracy. In addition,
the full-field PSF is hopefully applied in computing the significant
modulation transfer function (MTF) data in less time using an FFTalgorithm, higher accuracy image simulation by the convolution of the
input object and the varied PSF.

precision and tracking ability. Dual band infrared imaging system canreceive different wave band of infrared radiation. Therefore, the image
quality of optical system plays an important role in the joint transform
correlator(JTC).According to the requirements of the joint transform
correlator (JTC), the processes of optical design including the allocationof parameters and the selection of initial structure are presented. The
infrared dual band coaxial telephoto system is designed for target
detection. The system which is composed of four lenses can image inboth 3µm~5µm and 8µm~12µm wavebands. The focal length is 200 mm
and the relative aperture is 1:3. The system has the characteristics ofsmall volume and compact structure. The optical system image quality
is evaluated with ZEMAX optical design software. The results haveshown that MTFs of the system are 0.62 and 0.35 for both wavebands
respectively at 17lp/mm of spatial frequency which are closed to thediffraction limited curve. The relative aperture, field of view, and focal
length are same for both spectral regions. The system meets therequirements of technical specification and improves the ability of JTC
in target tracking and recognition.

8557-40, Poster Session

8557-32, Poster Session

A high-speed and small-volume IR zoom
lens using root-exchange theory and DOE
element

Design and experimental research on
miniature fiber-optic displacement sensor

Liu Lin, Sun Xing, Zhang xing de, North China ResearchInstitute of Electro-Optics (China)

Fei Gao, Jun Yang, Harbin Engineering Univ. (China)

The high-speed and small-volume mid-wave IR zoom lens capableof 16x magnification using a 320?256 IR FPA detector has been
described. The system magnification can be continuously adjusted bysimply moving two lens groups,which uses the root-exchange theory.
The system also contains much less optical material and has a very
simple structure by using DOE elements. Based on the characteristics,
the chromatic aberration was balanced. Research on the thermal
analysis and compensation is considered. DOE elements make thezoom lens maintain its performance when it is operating between 0°C
and 60°C.The results show the high magnification zoom lens design
performance, with small volume and light weight. The aberration of thesystem were well corrected and diffraction limited performance wasachieved in required temperature range.

A detecting method based on Fizeau interferometer for fiberoptic displacement sensing is presented to detect high-precisiondisplacement measurement with order of nanometer or sub-nanometer.
On the basis of optical interferometry and common-path Fizeau
interferometer, micro displacement can be detected by accurately
measuring the distance changes between the surfaces of fiber-optic
collimator and measuring mirror. Its characteristics are as follows: (1)With common-path interferometer, environmental dependence of energy
transmitting fiber to ambient temperature is eliminated, then the effectof ambient temperature variation to the system is reduced; (2) With themethod of optical frequency phase-carrier modulation/demodulation
instead of electrically controlled phase modulator, the optical path isformed with all-fiber components to improve the application flexibilityof the system; (3) By micro fiber-optic collimator with diameter of 1 mm,
the overall dimensions of the displacement sensor is greatly reduced,
which makes the use of the sensor more flexible. In the paper, thestructure and parameters of micro all-fiber common-path fiber-optic
displacement sensor is studied, the experimental platform for highprecision displacement calibration is built, and a series of performance
tests are completed. Experimental results show: with the displacement
length of 0-8 mm, the measuring resolution of the micro fiber-optic
displacement sensor can reach 0.1 nm, the measuring dynamic range
can get 158 dB, which indicate that the micro fiber-optic displacement
sensor has superior performances with high resolution, high precisionand large dynamic range.

8557-39, Poster Session

Infrared dual-band telephoto design used injoint transform correlator
Mu Da, Dong Jianing, Chunyun Xu, Changchun Univ. of Scienceand Technology (China)
On the basis of optical correlation detection, photoelectric hybrid
joint transform correlator(JTC) is widely used in military, aviation andintelligentization, etc. It has the advantages of great flexibility andhigh precision of recognition. However, the optical system which is in
front of joint transform correlator(JTC) is applied to receive the infrared
radiation of the target. It also has a certain influence on JTC’s detecting

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8557-41, Poster Session

Optical design of solar blind ultraviolet
warning system
Quanyong Li, Chunyun Xu, Jianing Dong, Changchun Univ. of
Science and Technology (China)
Ultraviolet warning technology is one of the important methods formissile warning. “Solar blind region” provides a very effective way todetect the target for missile approaching alarm. In order to find thetarget by detecting the ultraviolet radiation of missile efflux plasma,
ultraviolet optical system design of large field of view and large relative
aperture is the key for the technology of ultraviolet detection. From theacademic point of view, the structure parameters are determined for2048?2048 ultraviolet CCD detector according to the requirements ofultraviolet warning system. The refractive ultraviolet warning opticalsystem is designed for 0.24µm ~0.28µm waveband with ZEMAX opticaldesign software. The focal length is 41mm, the field of view is 46°and
the relative aperture is 1:3.5. In order to ensure the detected energy,
aspherical and binary surface are adopted to reduce the aberrationand spot size of the system. Within the 0.8 field of view RMS of spot
diagram is less than 13µm. It is smaller than the pixel size 13.5µm of
ultraviolet CCD. The energy concentration is more than 80%. This
optical system has long focal length and large relative aperture thatmeet the energy requirements of warning system. Large field of view
can satisfy the range of searching targets. The spot diagram RMS
of each field of view is so small that can meet the requirement of

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image quality. In addition, the system is composed of six lenses. The
structure of it is simple, the volume is small and the application is very
convenient.

8557-42, Poster Session

Designing adapted to fabricating ofholographic silver gratings
Amir Asgari, Amirkabir Univ. of Technology (Iran, Islamic
Republic of); Naser Partovi, NSTRI Optic & Laser Research
School (Iran, Islamic Republic of); Hooshang Araghi, Amirkabir
Univ. of Technology (Iran, Islamic Republic of); Eesa Alidokht,
Mohammad Hadi Maleki, NSTRI Optic & Laser Research School(Iran, Islamic Republic of)Some holographic super Gaussian silver gratings were optimizedin 700-1100nm bandwidth for stretching and compressing pulse
in chirped pulse amplification technology. Accordingly, the genetic
algorithm (GA) was employed by Grating Solver software to optimize
groove spacing, groove depth and groove shape of the grating; then,the rigorous coupled wave analysis was used to analyze the grating
diffraction efficiency (DE) as a function of period, depth, angle ofincidence, wavelength and duty cycle. GA and developing model of
S.Austin et al. (for designing holographically fabricated periodical
structures in a positive photoresist) were used to obtain manufacturing
parameters (exposure energy densities, development time, groove
spacing and littrow angle). Accordingly, Kpp1206 photoresist was
employed for modeling of grating profile. This paper was devoted toconsider super Gaussian gratings. Therefore, approximately identical
exposure energy density intervals were used for optimizing grating
profile. Two optimized silver gratings (for central wavelengths of 800
and 950nm in the 700-900 nm and 800-1100nm intervals) for TM
polarized light in the 1st order (littrow mount) have been achieved.
Following results were obtained: (1) DE>92% in the bandpass of>100nm and approximately ±20° difference from littrow angle in the
700-900nm range and DEmax>94.5% at ~830nm. (2) DE>92.5% in
the bandpass of >300nm and approximately ±10° difference fromlittrow angle in the 800-1100 nm range and DEmax>95.5% at ~925nm.
Moreover, a silver grating for the central wavelength of 1060nm desiredfor Nd:YAG and Nd:Glass lasers, with DEmax~ 97% was obtained.
Also, it was found that super Gaussian gratings with the depth of ~170250nm and duty cycle of ~ 0.3-0.65 have maximum DE in 1064nm.

8557-43, Poster Session

Design of all-reflective zoom optical systemof wide field-of-view with 3 mirrors
Lifei Zhang, Jun Chang, Aman Wei, Jiao Cao, Jiao Ouyang,
Beijing Institute of Technology (China)
All reflective zoom optical systems have advantages of no color
aberration and lightweight which have a wide application prospects inspace optical system. All reflective zoom optical systems, which havebeen designed, all use telephoto construction. And these systems havedisadvantages of big obscuration and small field of view. So in orderto satisfy of requests the wide spectrum and field of view of space
optical system, this paper design a novel all reflective zoom opticalsystem which uses anti-telephoto construction with 3 mirrors. Firstly,using the zoom theory of differential, the initial configuration with 2zoom ratio was obtained. Then simulating and optimizing the systemwith Zemax that is software of the optical design, we get a novel allreflective zoom optical system. It has a smaller obscuration and bigger
field of view than traditional reflective zoom optical system. At last, theimage qualities of this system was evaluated and concluded. And theimage qualities of this novel all reflective zoom system is well and theconstruction of the optical system is reasonable. It can be applied inspace optical system.

8557-44, Poster Session

Study of an ultra-short-throw projector
optical system design using the asphericalsurfaces
Yong Wang, Xuemin Cheng, Tsinghua Univ. (China); Qun Hao,
Beijing Institute of Technology (China)
The ultra-short-throw projector has been popular these days becauseof its advantages of occupying little space to light up a big screen,
reducing set up time, etc. The optical systems used in these projectors
need to achieve special performance qualities, especially a small
projection distance. To get a wide field of view while maintaining highoptical performance and compact size, a tilted and decentered opticalsystem used in the ultra-short-throw projector is presented in thispaper.
The optical system has the non-rotationally symmetric aberrations
brought about by tilted and decentered lens and a large field of view,
and vector aberration theory is used to analyze the aberrations and help
to produce the initial structure. To add the degrees of freedom in design
and reduce the number of lens elements, the aspherical surfaces aredesigned to correct the aberrations. Thus the relationship between thefields of view and the pupil aberration is discussed to achieve a good
image quality. It is demonstrated that the MTF values and the relative
illumination could be improved regarding to the optimization of the
optical structure parameters in the non-rotationally symmetric opticalsystem. The presented optical system has a projection distance of 300
mm, and the maximum distortion is no more than 5%. Its cost is taken
into account as well; its advancements in manufacturing technology
facilitate the utilization of aspherical surfaces without adding too much
expenditure.

8557-45, Poster Session

Prototype design of an all-reflective noncoaxial optical zooming system for spacecamera application without moving elements
based on deformable mirror
Hui Zhao, Xuewu Fan, Gangyi Zou, Zhihai Pang, Wei Wang, Rui
Guo, Yunfei Du, Yu Su, Xi’an Institute of Optics and Precision
Mechanics (China)
Nowadays, in order to obtain remote-sensing images with different
resolutions, space cameras with different focal length installed on
different platforms are used. However, this is not an efficient way forspace-borne reconnaissance especially when emergencies happen. If
the focal length can be changed, only one camera on a single platform
is flexible enough to obtain the required information.
As a long established technique, optical zooming allows us to adopt
only one camera to capture images with variable resolution and variable
field of view (FOV). The development of this technique undergoes
three stages: from refractive system to reflective system, from co-axial
system to non-coaxial system, from system with moving elements tosystem without moving elements.
In this paper, an all-reflective non-coaxial optical zooming system
is designed. Considering the sensitiveness of satellite platform tovibrations, traditional zooming technique in which moving elements
are indispensable is not suitable. Instead, a deformable mirror (DM)whose curvature radius can be changed electronically is introduced. By
carefully selecting the optical power of conventional reflective mirrors
surrounding the DM, the overall focal length of the system can be 4xchanged with the slight variation of curvature radius of DM. The system
performance is approaching diffraction-limited according to diverse
criteria and what is the most important is that the maximum stoke of
DM is still within its physical limits (less than 9um). The proposal of thisprototype is a big progress in optical zooming system design and isvery meaningful for space camera application.

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Conference 8557:
Optical Design and Testing V

8557-46, Poster Session

The design of a stepper motor control-based
high-precision varifocal imaging opticalsystemBai Xiang, Beijing Institute of Tracking and Telecommunications
Technology (China)
With high speed developing Chinese spaceflight project, telescopedemands more advanced, requiring the optical zoom system. The
excellence of zoom is in despite of the target size or distance changed,
it image still appropriate dimension easy to looking. So in recent
years we produced telescope almost used zoom. The paper first brief
introduces principle and composing the optical zoom system. It is
made up of fixed mirrors of foreside, mirrors of variofocus, mirrors ofcompensation and fixed mirrors of rearward. Then paper introduces
often used an optical zoom system of cam frame principle and existed
problems. The optical zoom system of cam frame is used cam control
mirrors of variofocus and compensation motion, to realize zoom andadjust position of image. But this system has some problems. The
problems are big shake of optical axis and high error output of real-time
focus length. To these problems we designs a precision optical zoom
system, used two step motors replace cam frame to command distanceof mirrors of variofocus and compensation motion, and used rolling
linear path replace sliding path to control direction of mirrors motion,and used grating ruler replaces potentiometer measured numeral of
focal length to realize real-time output. The numeral does feedback
signal to realize closed loop control by step motor. The excellencesof this new system are precision controlled distance of linear motion,
reduced shake of optical axis, precision output of real-time focus
length, and high reliability of system. So the new system compared
the old system shake of optical axis reduces 90%, alignment accuracy
increases 80%. It resolves existed problems of the optical zoom systemof cam frame. This precision optical zoom system can accomplishes
measure of high-degree of accuracy.

8557-47, Poster Session

Design of cooled athermalized infrared
telephoto lens
Yu Zhang, Jiyang Shang, Yue Xu, Wensheng Wang, Changchun
Univ. of Science and Technology (China)
With the development of the technology of infrared, infrared opticalsystem has been widely used in many fields, especially in target
detection and recognition. While the merit of infrared optical systemis that it can not only detect all-weather but also detect the target in
the poor conditions such as turbid air or smoke, flog and snow. So
IR optical system is much more appropriate to be applied in clutteredand formidable conditions. The change of temperature could degrade
image quality of the infrared optical system. So the difficulty and key inthe designing of LWIR optical systems for working under temperature
range of -60°C~80°C is athermalization. The effective focal length of
the infrared optical system should be large enough to ensure the long
distance detecting. The relative aperture should be large enough toensure adequate energy.
In this paper, cooled infrared focal plane arrays is used as infrared
detector, the pixel size is 35µm. The working waveband is 8-12µm. Its
resolving power is 17cy/mm. The infrared telephoto lens is designed
which is composed of four pieces of lenses, it meets the designing
requirements and has good image quality. The material which we chosezinc selenide, zinc sulfide and germanium is commonly used in IR
waveband. The working temperature range is -60°C~80°C. In order tobalance the chromatic aberration and thermal aberration, two asphericalsurfaces are used in this cooled athermalized infrared optical system.
The effective focal length is 100mm and the F-number is 2.The full fieldof view is 7.04°. The curve of MTF is close to diffraction limit. Within theworking temperature, the value of MTF at 17cy/mm is always large than
0.4. The result shows that the infrared optical system achieved better

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athermal performances at the working temperature range. The image
quality of the system approaches the diffractive limit. In addition, theoptical system has many advantages, such as simple structure, lightweight and high reliability. This telephoto lens can be used for infrared
target detection.

8557-48, Poster Session

Design of low-distortion single fingerprintacquisition system
Zheming Wu, Tianjin Univ. of Technology (China)
In order to get high resolution and low distortion, a method ofaberration correction for the trapezoid distortion of the single fingerprintacquisition optical system is proposed in this paper, which combinesnearly telecentric optical path with the inclined plane compensation.
With this method, not only the distortion of system can be reduced
using the character of telecentric optical path, but also the asymmetricaberration caused by the tilted object plane can be compensatedwith setting the angles of the fingerprint collecting prism. An actual
fingerprint acquisition system is designed also. There is a fingerprintcollecting prism and a follow-up lens in the system. The structure
parameters including the angles of the prism and the position of thepupil are set with little aberrations and low distortion. The 0.43%
maximum grid distortion and the 500dpi resolution of fingerprintacquisition system can be obtained. The optical length of this system
is in 45mm, the image sensor is 1/3.5’’CMOS, the size of object planeis 16mm?18mm. The MTF of the system is more than 0.5 at 50lp/
mm in the majority of field views. The system is small and Simple. The
experimental results show that there is almost no trapezoidal distortionin the actual grid image which is collected and it has been clear enoughto be able to distinguish pores on the fingerprint image. The grid
distortion and imaging quality of the system almost meet the standardof the FBI fingerprint scanning system.

8557-49, Poster Session

Design of blue LEDs arrays with high opticalpower
Pengzhi Lu, Bin Xue, Hua Yang, Huaiwen Zheng, Xiaoyan
Yi, Jing Li, Junxi Wang, Guohong Wang, Institute of
Semiconductors (China)
Technical progress in the field of blue light emitting diodes (LEDs) basedon III-V compounds has been breathtaking during recent years aroundthe world. With the rapid development of the device, high optical poweris expected from blue LEDs in a wide range of applications such as
optical-communications, medical optics and Biomedical optics.
In this paper, an array of blue LEDs with high optical power is presented
and discussed. Optical of the novel design is completed with the helpof running simulation in TracePro to predict the performance of themodule.
Cree XP-E LEDs with a square reflector was used in the novel design. In
addition, the length and depth of the reflector was 23.7mm and 20mm
respectively.
Optical simulation obtained from TracePro shows that optical output
power of the LED array could reach 8130mW with a uniform squarespot.
To verify the simulation results, Aluminum substrate, Copper substrateand Aluminum reflector have been made, respectively.
From the relationship between input current (A) and optical power (mW)of the samples with Aluminum substrate and Copper substrate, It canbe observed that the optical power of sample 2 was higher than thatof sample 1 and it can be attributed to the better thermal dispersion
performance of Copper. The optical power of sample 1and sample 2
was 8126mW and 9445mW at 2A, respectively. The experiment resultof sample 1 is consistent with previous simulation. Due to the better

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thermal characteristic of Copper substrate, the optical power of sample
2 is even higher than the simulated result.

8557-50, Poster Session

Compact optical imaging system for star
tracker with long focal length and perfectthermal adaptability
Yiqun Ji, Hucheng He, Rongbao Shi, Soochow Univ. (China)
Star camera is a kind of astronomic navigation equipment for positionand state information acquisition. There are two kinds of star camera,
the star sensor and the star tracker. Different from star sensor, star
tracker is usually applied for certain star detection, and with small
field of view but long focal length. According to the requirement of thecustomer, a star tracker optical imaging system is designed for Polaris
detection. First of all, the determination of key parameters of the opticalsystem is analysis in the paper. Secondly, a suitable configuration ischosen after comparison and the optimally design method is given.
Finally, the design result and its performance evaluation are presented.
The main index parameters of the designed system are as follow. It
works at VNIR (0.6µm~1.1µm) waveband according to the spectrum of
the Polaris. Its view field is 0.5 degree. And the focal length is 1000mm
and the entrance pupil diameter is 80mm. The optimally designed
lens is only 80mm in length. A Macsutov-Cassegrain type based lenswith the pre determined parameters is designed imagery tele-centric.
The lens is compact and with good performance. And the prominent
advantage is its perfect thermal adaptability, which is from -40 to 60
centigrade. Its MTF (Modulation Transform Function) reaches diffraction
limit. The spot diagrams after tracing are quit near a circle. And about
80% of the energy is encircled in a CCD pixel. The distortion is lessthan 1%.

8557-51, Poster Session

Optimization design and error analysis ofphotoelectric autocollimator
Lei Gao, Bixi Yan, Beijing Information Science & Technology
Univ. (China)
A photoelectric autocollimator employing an area CCD as its target
receiver, which is specially used in numerical stage calibration
is optimized, and the various error factors are analyzed. The
autocollimator measuring range is designed between -30’ and+’30’, andthe expecting accuracy is less than 2”.
By using ZEMAX software, the image qualities are evaluated andoptimized to make sure the spherical and coma aberrations of thecollimating system are less than 0.2mm and 0.035mm respectively;
the RMS radius is close to 6.45 microns, which is identified with theresolution of the CCD, and the MTF is greater than 0.3 in the full field ofview, 0.5 in centre field at the corresponding frequency of the imaging
system. Then, the tolerance analysis function of ZEMAX is applied tosimulate the process of the components’ machining and assembly.
We take the RMS SPOT RADIUS and Diff. MTF Avg as the criteria of
tolerance analysis, and the Monte Carlo analysis shows that 90% of the
RMS radiuses are less than 6.45microns and 90% of the MTF are larger
than 0.3 and meet the requirement.
The mechanical structure is designed according to the upper tolerance
analysis.
At last, the errors of the optical-mechanical system are analyzed andcalculated. The result demonstrates that the errors origin mainly fromfabrication and alignment, which are all about 04”. The principle error
is about0.35” and the aiming error is about 0.2” . The error synthesisshows that the instrument can meet the demands of the design
accuracy, which is also consistent with the experiment.

8557-52, Poster Session

Design of a front objective in a monocularzoom video microscope
Liao Wenzhe, Xiao Zexin, Guilin Univ. of Electronic Technology(China)Nowadays, the monocular zoom video microscope is one of themost widely used detection equipment at mainstream position in theelectronics industry. The front objective of this kind of microscope isbenefit for the enlargement of its magnification. At present, the similar
products are mainly designed out by non-coaxial system, which means
the optical axises between front objective and objective are un-coaxial.
However, the actual front objective of monocular zoom microscope
uses coaxial system. So a particular front objective designed for thezoom microscope is imperative. At first, we point out this unique designidea form the special imaging relationship between front objective
and objective in zoom microscope. And then we choose the positionof entrance pupil, numerical aperture and the layout. At last we
enumerated examples of the zoom in and out lenses, and analyze thedesign methods of their similarities and differences.

8557-53, Poster Session

Design of reflective active zoom systems
with four mirrors
Shen Benlan M.D., Jun Chang, Beijing Institute of Technology(China)The traditional zoom systems usually change the spaces between
optical components to realize the variable focal lengths. Based on
active optics, a new type of reflective active zoom system with four
mirrors is proposed, which is different from the traditional zoom system,
and realizes the different focal lengths through changing the curvatureradius of two reflectors. The new zoom system consists of an afocal
front group with three mirrors, and the fourth mirror used for focusing.
The relation among the four mirrors is determined by the Pezval
condition. The primary and secondary mirrors are both deformablemirrors, which contribute to the transition among the minimum, middle
and maximum focal lengths by the curvature radius variation controlled
by the voltage, with the constraint limiting its’ change rules. According
to the designed system characteristics and the practical requirements,
based on 3rd-order aberration theory, a set of Seidel aberration
coefficient functions are established, with the constraint limitation.
Then the initial construction parameters of the optical system can beachieved. The new active zoom system with four mirrors can realizethat the zoom rario is 3, the focal lengths vary from 100mm to 300mm,
the field angle of view range is 2.1°~0.7°, and the wide working band isfrom the visible to the infrared. At the same time, because of the control
flexibility, the active optical zoom system has the potential to be widely
applied in remote sensing, life medical and other fields.

8557-54, Poster Session

Design and research of the second parallel
optical path of the telescope photoelectronic
imaging system
Chen Gang, Guilin Univ. of Electronic Technology (China);
XingYu Gao, Liu Zhou OVM Machinery Co., Ltd. (China);
Dao Yin Yu, Tianjin Univ. (China); Ze-Xin Xiao, Guilin Univ. ofElectronic Technology (China)
A second parallel CCD (CMOS) camera imaging system for an
telescope objective with the fixed D/f’ is proposed. For the direct
imaging system that the CCD target surface coincides with theimaging surface of the telescope objective, it shows the outstanding

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Conference 8557:
Optical Design and Testing V
performance of more than doubled resolution compared with theordinary telescope objective with the same D/f’. On the base of
discussions about the innovative telescope optical imaging system,
three design examples are compared and analyzed. The relation
between the image field and the optical elements of the second parallel
path is clarified, which provides a operable method for readers. This
practice has proved that it is a new telescope objective photoelectronic
imaging system with broad application prospects.

8557-55, Poster Session

Design and modeling of a new CO2 laser
heater for thin film deposition applications
Mohammad Reza Rashidian Vaziri, Fereshteh Hajiesmaeilbaigi,
Mohammad Hadi Maleki, Univ. of Tehran (Iran, Islamic Republicof)In this paper, we report on designing a new raster-scanned CO2 laser
heater for homogeneous heating of the disk-shaped substrates [1]. This
new design aims at concentrating the laser energy near the substrate
peripheral edge, which mostly tends to remain cooler than the innerparts during the heating process. Our design benefits from using a CW
medical CO2 laser, which at an affordable price can be found by any
research group involved in PLD. The capability of this raster-scanned
method for producing a highly homogenous temperature distribution
on the disk depositioning face has been proved by a comprehensive
transient heat diffusion model. Our computational model shows that aminimum temperature standard deviation of 1.5 K is achievable using
our heater design for a laser power of 7 W. The capability of producing
such great temperature uniformity with our CO2 laser heater design
may be quite of assistance in thin film deposition applications. It canfavorably be used in preparation of crystalline thin films where their
quality depend on the maintained temperature during the depositioning
time interval. This heater can also be used for CO2 laser conditioningof the prepared thin films. Furthermore, a set of experiments havebeen conducted to measure the substrate temperature. The aim of themeasurements was to estimate the emissivity of the substrate material(YAG in our case) which was necessary for solving the heat diffusion
equation and for comparing the results with the predicted temperature
values obtained from modeling.
[1] M.R. Rashidian Vaziri, F. Hajiesmaeilbaigi, and M.H. Maleki, Opt.
Eng. 51(4), 044301 (2012).

8557-56, Poster Session

A new type of wide spectral coverageechelle spectrometer design for ICP-AES
Shoajie Chen, Yuguo Tang, Bayan heshig, Xiangdong Qi,
Changchun Institute of Optics, Fine Mechanics and Physics(China); Wenyu Zhu, Changchun Institute of Optics, Fine
Mechanics and Physics (China) and Medical Instrument Ltd. of
CIOMP (China)
The inductively coupled plasma atomic emission spectrometry (ICPAES) has always attracted great interest and is widely used for routine
elemental analysis. While one drawback of this technique is the factthat conventional Czerny-Turner spectrographs in combination with
CCD cameras are very limited either in terms of spectral resolution or interms of simultaneously detectable spectral range. A cross-dispersion
system with echelle grating and prism has therefore been developed,
and the spectral image is directed by large area charge coupleddevice (CCD). This configuration meets the needs of atomic emission
spectroscopy well, since it has many benefits including high resolving
power, spectral coverage, high sensitivity, and high optical throughput.
While, because the limitation of the development of detectors, it isdifficult to complete wide spectral coverage measurement. Due tothe improvements in optical design, this system can detect the wide

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spectral coverage from 180nm to 900nm simply by rotating the prism
two times, and these three ranges are 180nm-250nm, 250nm-400nm
and 400nm-900nm, with a high resolution 0.008nm@200nm. The
detection of different elements only needs to choose appropriate
wavelength coverage, thus lots of elements can be analyzed withina quite short time. The novel optical design of this instrument ispresented and its merits are discussed in this paper. The optical
spectral resolution and the precision of wavelength calibration are foundto be satisfactory and within the design goals. Experiments show that
the ICP-AES with echelle spectrometer is available to detect multiple
elements within a short time correctly, the wavelength precision is better
than 0.01nm.

8557-57, Poster Session

Optical system design of polarization
imaging spectrometer for ground-based
astronomical observation
Lingying Chang, Xi’an Univ. of Posts and Telecommunications(China)In order to obtain polarimetric hyper spectral observation of theastronomical objects such as stars nebulae and extragalactic, thepolarization imaging spectrometer for ground-based astronomical
observation was developed. It can be quickly electrically tunable
for spectral channels by acousto-optic tunable filters for opticaldispersion element with low noise back-illuminated CCD as detector,
and the orthogonal polarization O light and E light spectrum image
was obtained simultaneously at multidimensional target.In this paper,First, the overall scheme of astronomical observations for polarization
imaging spectrometer was introduced, then described the opticalparameters of each imaging subsystems. It covers the spectral bandfrom 450nm to 900nm with a spectral resolution near 10nm, and theoptical system can provide about 4.1&#61602; view field angle. Finally,
the design of the optical system was completed by the optical design
software CODE-V, which imaging resolution excelled 40 lp/ mm whenthe modulation transfer function (MTF) reaches 0.6.

8557-58, Poster Session

A novel optical beam deflection detection
system based on aspheric lens for highspeed atomic force microscope
Jianyong Zhao, Guangyi Shang, Junen Yao, Weitao Gong,
BeiHang Univ. (China)
The optical lever method is widely used to detect the cantileverdeflection in atomic force microscope (AFM) for its simple mechanismand high sensitivity. How to focus the diode laser beam on the verysmall cantilever with a spot of several microns in diameter is a key
and difficult issue in high speed AFM. An ingenious designed opticalbeam deflection detection system based on aspheric lens is presented.
An aspheric lens which can focus laser beam and correct sphericalaberration is fixed by an adjustable bolt above the cantilever. Two laserline beamsplitter cubes are installed back to back over the aspheric lenswith a 3mm beam diode laser and a quadrant photodetector separately
placed in two sides at the same height. The collimated laser beam isreflected down by the beamsplitter, incident on the aspheric lens at an
off-centered position. The outgoing beam is focused onto the cantilever
and reflected back onto another part of the aspheric lens. Change in
the angle of the reflection caused by cantilever deflection results in aparallel shift of the exiting laser beam after the aspheric lens. The laser
beam is reflected onto the photodetector by the other beamsplitter
where the cantilever deflection is measured by the difference in current
between the top and the bottom elements of the photodetector.
Experiment results show that diode laser beam can be focused witha spot of less than 16 microns in diameter, which meet the deflection
detection requirement for high speed AFM.

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8557-59, Poster Session

Design and theoretical investigation of
nanograting for XUV outcoupler
Ying-Ying Yang, Institute of Semiconductors (China); Wei
Sun, Laboratory of solid state laser sources, Institute of
Semiconductors, Chinese academy of sciences (China); Ling
Zhang, Huai-juan Yu, Xue-Chun Lin, Institute of Semiconductors(China)A nano-periodical highly-efficient blazed grating is fully theoreticallyinvestigated for outcoupling extreme-ultraviolet (XUV) radiation. The
rigorous coupled-wave analysis (RCWA) method with S-matrix is
employed to optimize the parameter of the grating. It would allow
conducting high resolution spectroscopy of the 1s-2s transition in He
at around 61 nm with extreme precision. The grating is designed to beetched into its top layers as a highly-reflective mirror for IR light andoutcoulper for XUV. The XUV diffraction efficiency was determined to be
grater than 20% in the range from 36 nm to 79 nm and consistent withthe experimental data.

8557-60, Poster Session

Off-axis illumination of lithography tool
Xing Han, Lin Li, Beijing Institute of Technology (China); Bin Ma,
Beijing Institute of Technology (China) and Univ. of Rochester(United States)
Lithography tool is a necessary part for LSI and VLSI. Off-axis
illumination technology is an effective way to reducing resolutionof lithography. This paper introduction the basic components oflithography tool, the principle of off-axis illumination reducing
the resolution of lithography and do some research about two
implementations of OAI technology.

8557-61, Poster Session

Research on design of a cubic conjugate
phase mask having the capability ofcontrolling the bandwidth of wave-front
coding system

extended to other phase masks and the expected bandwidth selection
effect can be obtained by combining two conjugate masks with relative
shift together.
The work reported is complementary to the field of wave-front coding.

8557-62, Poster Session

Aberration retrieval for annular pupils usingparametric model of point spread function
Xinhua Chen, Weimin Shen, Soochow Univ. (China)
Because of imperfect design and manufacture, performances of opticalsystems are affected by various aberrations. These aberrations willcause image blur and distortion. Adjustment and calibration of opticalsystem can be performed if its aberrations are known, and this canbe realized by measuring its pupil wavefront. Wavefront interferometry
and Shack-Hartmann wavefront sensing method are two traditional
wavefront measurement methods. Compared with these two methods,
image-based wavefront sensing method can determine aberrations
directly from image formed by the optical system with no extra
hardware. This method has attracted more and more attentions forthis unique advantage, and has been successfully applied in many
domains such as large telescope alignment, X-ray imaging and so on.
For annular pupil, wavefront can be decomposed with annular Zernike
polynomials. The coefficients of these polynomials can be retrieved
using spot intensity images-based aberration retrieval method. In thispaper, we propose an aberration retrieval method for annular pupils
using proposed parametric model of point spread function (PSF).
With this model, the diffraction integral for annular pupils is expressedwith Bessel-series representation and annular Zernike coefficients.
Conjugate gradient algorithm is used to retrieve aberration coefficientsof annular pupil from the corresponding spot intensity images. The
iterative calculations of objective function and its gradient function
are required for this algorithm. These calculations are accelerated byusing the parametric model’s analytical expression instead of Fouriertransforms. Numerical simulation and experiment are performed tovalidate this aberration retrieval method.

8557-63, Poster Session

Analysis on the effect of extinction ratio inbirefringent measurement by phase-stepping
methodHui Zhao, Yingcai Li, Xi’an Institute of Optics and Precision
Mechanics (China)

Xusheng Zhang, Haoyu Wang, Chuan He, Beijing Institute ofTechnology (China)

Wave-front coding is a widely known technique used to enlarge thedepth of field (DOF) of incoherent imaging system and the phase masks
are the key to generate large DOF effect.

The analysis on the effect of extinction ratios of linear polarizer andanalyser in the birefringent retardation measurement by a five-stepphase-shifting method based on plane polariscope setup is presented.
The phase stepping method with automatic phase upwrapping
algorithm is well known to be one of the most effective ways for whole
field photoelastic stress induced birefringence analysis. However, thephase stepping methods having been reported in the past literatures
have not addressed the potential errors produced by extinction ratiosof linear polarizers. The theoretical analysis on how the extinction ratiosof linear polarizer and analyser act in our presented five-step phaseshifting method is made and discussed in this paper. Stokes vector andMueller matrix are used to carry such theoretical analysis. This five-stepphase shifting method will not introduce errors of quarter wave plates.
Also, when this five-step method is used in stress-induced photoelastic
birefringence measurement, the isoclinic angle is not necessary to beobtained prior to the measurement of phase retardation, so the dataprocessing can be simplified and the error of isoclinic angle will notaffect the accuracy of phase retardation measurement. The theoreticalanalysis and experiment in this paper show that extinction ratios oflinear polarizer and analyser do not cause significant errors in thepresented five-step phase shifting method. Standard mica waveplateswith given phase retardations are tested, and the results agree well with

Many phase masks have been designed to realize the wave-front
coding and the cubic type is the most popular one. In paper [Proc.
SPIE Vol.4422 pp.34-42,2001], the authors derived an extended cubic
phase mask which not only contained cubic terms, but also had
quadratic, unitary and constant terms. Although those terms except the
cubic one have no effect in enlarging the DOF, according to our further
investigation, the extended cubic phase mask has the capability ofchanging the system bandwidth, indicating that the mask could play arole of bandwidth selection and this effect is rarely noticed in existing
literatures.
In this paper, we make three contributions. First, a new procedure
is proposed to derive the extended cubic phase mask. Second, by
splitting and re-combining the terms of the phase function, a newphase mask containing two conjugate cubic terms is generated andcan be physically realized by shifting and superposing two cubic
phase mask having relative displacement in the pupil plane. With thevariation of displacement, the system bandwidth can be changed withdefocus invariance characteristics unchanged. Third, the results can be

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Conference 8557:
Optical Design and Testing V
the theoretical analysis and given values. Experimental setup of plane
polariscope herein includes the components of a 635nm semiconductor
laser, rotatable polarizer and analyser, a switchable-gain amplified
silicon photodetector and the compatible 16-bit data acquisition
system.

8557-66, Poster Session

Analysis and protection of stray light for the
space camera at geosynchronous orbit
Xiaorui Jin, Li Lin, Beijing Institute of Technology (China)

8557-64, Poster Session

Research on surface deformation of lensfastened by adhesive under gravity load andaberration analysis
Shaohua Guan, Institute of Optics and Electronics (China);
Tianmeng Ma, Quanzhong Wei, Institute of Optics andElectronics, CAS (China)
In the design and production of optical instruments, various kinds ofadhesive are used to mount optical system instead of screw, platen andother fixed parts. But in the assembly of high-accuracy lens and largeaperture lens, the effect of the curing stress of adhesive and gravity is
not be ignored, as a result, research on surface deformation of lens andaberration analysis is necessary.
In order to shorten design cycle and reduce costs, this paper designed
a simulation analysis about lens structure fastened by adhesive, whichmake use of finite element software (Ansys) based on finite element
basic theory. The following aspects are the major in this paper:a. The whole assembly model of lens fastened by adhesive was builtwith Solidworks;b. The lens deformation in two different directions of gravity was
analyzed, one was along the axial direction and the other was along theradial direction;c. The Zernike polynomials fitting algorithm was used to fit the surface
deformation with Matlab program, and the deformed surface mirror
values of PV and RMS was calculated;d. According to the relationship between Zernike polynomials andSeidel aberrations, aberrations induced by gravity load were analyzed;
e. Different thickness and different spots of adhesive were considered in
the analysis of assembly model.
The simulation results indicated that the surface deformation was within
the limits of permission, and proper thickness and spot of adhesive
were found. These results can be guideline in the practical assembly
work of lens.

8557-65, Poster Session

Stray light analysis of a space patrol
Huiyi Chen, Li Lin, Beijing Institute of Technology (China)
The stray light of a space patrol is analyzed in this paper. The spacepatrol is used to observe the Earth in space. In the paper the definitionsof stray lights in the optical system are introduced nand the stray lights
are classified based on their sources. After the analyzing the serious
harm situations of the stray lights in the optical system is presented.
Software Tracepro is used in analysis of stray light. The model of thespace patrol is established in the software and stray light simulation
and analysis of the space patrol are presented based on the evaluation
criterion of maximum irradiance value. Three different situations are
discussed. First, sunlight directly irradiates onto the sensitive surfaceof the detector; second, sunlight enters the system by the reflections of
the space patrol’s body; and finally sunlight reflecting from the moon’s
surface irradiates onto the sensitive surface of detector by the reflectionof the space patrol’s body. In each situation, we respectively calculatedifferent elevation angles in ranges between 15°~45°by the ray tracing
method in the solar azimuth of 0°and 30°. Transmission paths of straylights are obtained by ray tracing data in different circumstances andthe important surfaces of the system are found out. Finally, somecorresponding stray light suppression measures which can help toreduce harm of stray light are proposed.
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Stray light is the general term for all non-normal transmission of light in
the optical system. The influence of stray light is different according to
optical system’s structure. Large area array camera at geosynchronous
orbit is facing more serious influence of stray light, especially for thesmall incident angle of sunlight on the system. It is in dire need of adetailed analysis of stray light of the basic shape of the optical system.In the paper, the influence on the camera used in space from stray lightand the necessity to eliminate stray light are presented. The definitionof the stray light factor and PST(point source transmittance) is briefed.
In tracepro, analysis of the impact of sunlight incident was made atdifferent angles on the space camera, in the case of stray light factor
for the quantitative evaluation. The design principle of the inside andoutside hood is presented for the R-C (Ritchey Chretien) optical system.
On this basis, in order to reduce stray light interference for the spacecamera, the primary and secondary mirror’s hoods were designed.
Finally, when sunlight at more than 3 ° incidence on the space camera,
the coefficient of stray light is less than 2%. It meets the engineering
requirements.

8557-67, Poster Session

Analysis of thermal shock strength andquality factor with infrared optical domes
Youtang Gao, NanYang Institute of Technology (China)
The development of infrared optical materials is always closely related
to the research and exploration of material science. The infrared opticaldomes bears shock and produces stress when the infrared opticaldomes mounted on the missile moving at a high speed is shocked byhigh temperature. According to principle of energy balance in fracture
mechanics proposed by D.P.H. Hasselman, the author analyzed thecrack extension and derived the relationship between Infrared opticalmaterials window model and thermal shock quality factor. Meanwhile,strong or weak of thermal shock for different samples whether they arethin or thick are compared through the operation of queuing algorithm.
The conclusion is the internal surface of the domes isn’t heated when
the window model is the thermal shock quality factor of thick sample
and the heating time is between heating time constant and diffusion
time constant. On the other hand, the internal surface of the domes
is being heated when the window model is the thermal shock quality
factor of thin sample and the heating time is between the two time
constants. The most optical domes parts in practice is belong the thinmodel. For the thin model, reducing the thickness of optical parts canimprove their thermal shock ability but mechanical impact stress factor
should be considered comprehensively to design optical parts.

8557-68, Poster Session

Off-axis three-mirror zoom system
perturbation analysis
Jiao Ouyang, Jun Chang, Lifei Zhang, Jiao Cao, Aman Wei,
Beijing Institute of Technology (China)
Reflective zoom system is widely used in the design of large size,
wide spectral, high resolution system due to its great superiority
in compacting size, system weight, aperture size, free chromaticaberration and thermo-stability. But for coaxial system, its disadvantageof obstruction renders the FOV (field of view) and light utilization rateunsatisfactory. Thus, to make the secondary and tertiary mirror offaxial is a good choice for optical designers. However, there are two
problems in the alignment of off-axis zoom optical system. First, theSeidel aberration theory is not applicable for a system without rotational

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symmetry. Second, it is hard to control the misalignment status whenzoomed. In this paper, the nodal aberration theory (sometimes iscalled vector aberration theory) worked out by Thompson is selected
to analyze the off-axis three-mirror zoom system. When perturbation
is applied to the system, coincident with the alignment in reality, theresidual aberration varies along with the movement of secondary andtertiary mirror. As the result, aberration character of misalignment threemirror-reflective zoom system is provided, which offers guidance formisalignment determination and makes sure of the normal operation of
the zoom system.

8557-69, Poster Session

Research on the real-time calibration of thevarifocal photoelectric imaging system
Bing Zhou, Fuyu Huang, Yu-dan Chen, Shijiazhuang MechanicalEngineering College (China)
In the varifocal photoelectric image system, the method of moving
two batteries of lenses along with the optical axis is usually adopted
to vary the system focal length. With this method, the focal length canbe changed directly by moving the varifocal lenses, and the image
quality can be improved during the zooming procedure mainly by thecompensating lenses, whose position is also changed with the shift ofthe varifocal lenses. However, influenced by the mechanical processing
technology, mechanical tolerance, and other factors, the radial deviation
between two types of the lenses will be produced unavoidably as they
move along with the optical axis in the actual varifocal optical system,
which may results in the variance of the optical axis before and after
zooming the focal length. This phenomenon is especially serious in thephotoelectric reconnaissance and tracking system with a long focal
length, and it affects the calculative precision of the target angularcoordinates for the succeeding signal processing system.
A real-time system for optical axis of the varifocal photoelectricreconnaissance and tracking system is designed in this paper. Twoimages are acquired by the DSP processing system before and after
zooming the focal length, and the varifocal and shifting coefficients arecalculated real-timely through extracting the feature points and affine
transform, etc, while the rotation coefficient equals to zero basically.
The shifting parameter can be used to calibrate the optical axis, andits calibration precision is less than one pixel. Besides, the varifocal
coefficient calculated by the affine transform, whose precision is far
higher than that obtained by the mechanism-potentiometer method,
can be treated as the output of the precise varifocal coefficient.
The real-time calibration of the varifocal photoelectric image system isrealized by the method of electronic processing, and this method has
a higher calibration precision, which can reduce the requirement of
mechanical processing technology and mechanical tolerance greatly
in the production procedure of the photoelectric reconnaissance andtracking system with a long focal length, and can make the systemeaser to implement.

8557-70, Poster Session

Accuracy analysis of surface figure
fitting based on optomechanical-thermal
technology
Xifa Song, Li Lin, Yifan Huang, Beijing Institute of Technology(China)Opto-mechanical-thermal technology is used more and more widely,but few people mentioned the accuracy of surface figure fitting. In thispaper, we analyzed the sections that may cause error based on thermal
analysis and mechanical analysis. We used error analysis to consider
the accuracy of surface figure fitting. We took into account of the errorof ABAQUS modeling, the initial error, the error of surface figure fitting ,the error of MATLAB and the error of ZEMAX.

And then we gave out the total error, and analyzed which is thedominant error, thus give support for Quadratic optimization design

8557-71, Poster Session

Multi-limit unsymmetrical MLIBD image
restoration algorithm
Yang Yang, Information Engineering Univ. (China); Chen Bo,
Peking Univ. (China)
A novel multi-limit unsymmetrical iterative blind deconvolution(MLIBD)
algorithm was presented to enhance the performance of adaptive optics
image restoration.The algorithm enhances the reliability of iterative blind
deconvolution by introducing the bandwidth limit into the frequency
domain of point spread(PSF),and adopts the PSF dynamic support
region estimation to improve the convergence speed.The unsymmetricalfactor is automatically computed to advance its adaptivity.Image
deconvolution comparing experiments between Richardson-Lucy IBD
and MLIBD were done,and the result indicates that the iteration number
is reduced by 22.4% and the peak signal-to-noise ratio is improved by
10.18dB with MLIBD method.The performance of MLIBD algorithm isoutstanding in the images restoration the FK5-857 adaptive optics andthe double-star adaptive optics.

8557-72, Poster Session

Polarization characteristics of a linearlypolarized laser beam after hollow light pipe
in projectors
PengFei Zhao, Shengtao Zhang, Yanhong Wang, Yunbo Shi,
North Univ. of China (China); XuYuan Chen, North Univ. of China(China) and Vestfold Univ. College (Norway)
Abstract: In this work, a multilayered dielectric film of SiO2 and Nb2O5
and metal film of silver are used as reflecting surface to fabricate hollow
light pipes separately. And the internal dimensions of the light pipes
is 0.157in(4mm)x0.157in(4mm)x1.65in(42mm). Linearly polarized laser
beam with wavelength of 532nm enters into the light pipes at the solid
angle of 42 degree. After multi-reflection process, laser beam comesout from the light pipe, then, irradiates a screen. With the adjustingof the polarization orientation of the input laser beam from 0 degree
to 90 degree, the polarization state of the laser beam after reflection
is changed from approximate linearly polarized to partially polarized,
which can be observed by rotation the polarizer placed before thescreen. And the depolarization ratio of the light pipe coated with metal
film is superior to the one coated with multilayered dielectric film. The
whole aforementioned experiment process can be well simulated using
a commercial available software ZEMAX. The polarization degree of
output beam can be calculated according to the simulation data of the
PPM (Polarization Pupil Map). Referring to the theoretical dependenceof the laser speckle contrast on the laser beam polarization degree,
laser speckle contrast from a glass diffuser is measured to exam thesimulated result. At last, through the simulation, the effects of thepolarization orientation and solid angle of the input laser beam, anddimensions of the light pipe on the polarization degree of output laser
light are discussed.

8557-73, Poster Session

Parameters affecting pattern fidelity and lineedge roughness under diffraction effects in
optical maskless lithography using a digital
micromirror device
Manseung Seo, Haeryung Kim, Taehyoung Lee, Tongmyong

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Conference 8557:
Optical Design and Testing V
Univ. (Korea, Republic of)8557-75, Poster Session

In optical maskless lithography in concern, a digital micromirror
device plays the role of a digital mask. Due to the spatial/temporalconfiguration of micromirror arrays/response or the specificationof illumination/projection optics, an array of beams reflected off
micromirrors may be considered as dispersive pixels. An irradiation
process may be considered as a pixel by pixel reflection. Therefore, thediffraction effect may not be negligible. In present study, a systematic
integration of an optical maskless lithography system based on binary
micromirror reflections is performed in consideration of the diffraction
effect. For the approval of the binary reflection off the micromirror, theoccupancy limit is employed. Parameters that affect pattern fidelity
and line edge roughness under diffraction effects at various occupancy
limits is investigated and simulation and experimental results areanalyzed. To improve image resolution, a method of dividing an image
pixel reflected off a single micromirror into equal-sized sub-pixels on atranslating substrate by the superposition of an array of image pixels is
adopted. However, the decrease of sub-pixel size through the increaseof the dynamic sub-pixelation degree results in a decrease of the scan
pitch which directly affects throughput. Thus, to increase throughput
while maintaining pattern fidelity and line edge roughness, the dynamic
sub-pixelation process is modified by using the hop degree and thelithography system parameters utilizing dynamic sub-pixelation are
adjusted. The potential of utilizing adjusted parameters for improving
image resolution and further enhancing pattern fidelity and line edge
roughness under diffraction effects is demonstrated through simulations
and experiments.

A model for simulating coherence of laser
light caused by Mie scattering

8557-74, Poster Session

We can conclude that the spatial coherence of the laser light can be
modulated by design the Mie scatter medium which will not cause the
big loss of the light transmission.

Wavefront fitting with Zernike polynomials
based on total variation regularization
methodLihong Lu, Tianjin Polytechnic Univ. (China); Qingyu Hou, Jinnan
Gong, Harbin Institute of Technology (China)
The wavefront of the measured optical surface and system are smoothand continuous. Therefore, the wavefront can be expressed by alinear combination of complete base function, and then the discrete
points with wavefront information can be fitted to the actual wavefront
precisely. The wavefront function can be achieved by fitting the opticalsurfaces date using Zernike polynomials because of the corresponding
relation between Zernike polynomials and Seidel aberrations, which has
been widely used in optical testing and optical design. The accurate
fitting coefficients can be achieved by using Least Square, GramSchmidt orthogonalization and Householder transformation with theaccurate measured values. However, there exist errors on phase values
obtaining by optimization algorithm, which cause the instable solution
obtaining by the common algorithms. In this paper, the reason of thestable solution cannot be achieved when proceed to fit wavefront by
Gram-Schmidt orthogonalization and Householder transformation is
deduced in theory. The essence of Gram-Schmidt orthogonalizationand Householder transformation is QR decomposition, and the only
difference between the two methods is the way to obtain the orthogonal
matrix. The Zernike coefficients fitting method based on total variation
regularization is presented to suppress the effects of errors in measured
data on fitting results. The solving model of Zernike coefficients isdeveloped, and the regularization term is introduced in solving model,
then the L-curve method is applied to determine the regularization
parameter and the modified steepest descent method is applied
to solve Zernike coefficients. The algorithm efficiency is proved bysimulation experiment.

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Yanhong Wang, Wenhong Gao, Wenhong Gao, Pengfei Zhao,
Xuyuan Chen, North Univ. of China (China)
In this work, in order to study coherent characteristics of the laser lightencountering Mie bulk scattering, a model for simulating coherence oflaser light caused by Mie scattering has been built up in ZEMAX opticaldesign software, which consists of a linear polarized laser source,
scattering medium, an interferometer configuration, and a photodetector. The linear polarized laser source is of wavelength 0.45 micron.
The scattering medium is a particle solution with variable parameters
including the index, the particle size, and the solution density. Theinterference configuration is a Young’s double-slit interferometer. Bychanging the index, the size, and the density of the particle in thesolution, respectively, the interference patterns are recorded. We havediscovered that the contrast of the interference patterns strongly
depends on the particle size and the density.
The results show that the interference fringe contrast changing from
1 to 0.14 has a monotonic decreasing relationship with the particle
density from 1000 cm-3 to 600000 cm-3 when the refractive index was
1.6 and the particle size was10 microns. The interference fringe contrast
decreases from 1 to 0.12 when the particle size increases from 10 to
100 micrometers under the condition of fixed the refractive index 1.6
and the particle density 5000 cm-3. However, the interference fringe
contrast hasn’t changed obviously with altering the refractive index.

8557-76, Poster Session

Fluid mechanics principle about manufacturetechnology of micro-lens generated onneeding positions
Jian Wu Sr., Kuanxin Yu Sr., Beijing Univ. of Technology (China)
In this paper a new fabrication technology of the micro-lens whichis generated on needing positions is suggested. Its process is asfollows. First a solidifiable ultraviolet optic glue drip is released on thehorizontal plane. When the droplet spreads, its shape will change withthe face tension. Final the droplet is irradiated by ultraviolet laser indue time and it can be solidified according to the designing shape. The
technology doesn’t need mould or masks, It is easy, quick and cheap.
It has application prospects in astronavigation, military affairs, biology,
chemistry and civil affair. In this paper fluid mechanics principle about
the optic micro-lens generated on needing positions is researched. A
surface equations set of viscous optic glue drip is given. The equations
set reflect relationship between coordinates of the surface curve. A
numerical calculation method is proposed. Some shape curves andcurvature radius curves for different contact angles between the glue
and glass base and different character lengths of the glue are given.
Methods influencing shapes of the glue drips are discussed. Decreasing
contact angles and character lengths can make spreading area tochange big and thickness to change small. Adulterating nanometer
quartz powder in the glue and milling the glass can change thecontact angle and the character lengths. So controlling adulteration
concentration and roughness of the glass, the optic mocro-lens with
ideal shape can be obtained. The research results have directive
significance to manufacture of the optic micro-lens generated onneeding positions.

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8557-78, Poster Session

8557-80, Poster Session

Fiber ring depolarizer with one degree of
freedom

Analysis of array image camera modes in thetest for dynamical focus position

Chunhua Wang, Qing Yang Yu, Li Li, Shengfei Zhang, Shanghai
Univ. (China)

Juanning Zhao, Xiaona Dong, Limin Gao, Hongguang Li, Xi’an
Institute of Optics and Precision Mechanics (China)

Depolarization techniques are an efficient way to solve the polarization
turbulence induced impairments in optical sensing systems. The
essential of depolarization is to split the light in two orthogonal
polarization directions equally in power and make all the split lights
incoherent as well. In this paper, a one-degree of freedom (DOF) tunable
single fiber ring depolarizer is proposed by specially setting the bendinduced birefringence in the fiber ring to behave as a half-wave plate(HWP) and with the optimal coupling ratio of the coupler. The methodsof making and testing the HWP-performance of the fiber ring are
analyzed and discussed. Depolarization can be realized by just rotating
the fiber ring instead of adjusting the polarization controller within thefiber ring as previous works did. In our experiment, a 12-meter longfiber ring depolarizer is demonstrated to depolarize a Fabry-Perot (FP)laser with 10-meter coherent length. Degree of polarization (DOP) of
1.5% can be easily reached by rotating the whole set of fiber ring.
The losses in the ring and the twist-induced birefringence are thekey factors that make DOP not equal to zero. Therefore, to reduce
the splicing losses and to coil the fiber with the best performance of
HWP and fix it are very crucial in fabricating the device. Moreover, if
inserting a polarizer ahead of the fiber ring, a full scale one degree of
freedom tunable depolarizer can be realized. The features of depolarizer
proposed are all-passive, compact, stable and low-cost, and with theability to depolarize narrow-band spectrum of light.

The focus spot position is one of the most significant parameters in
optical system, especially to the optical system including multiple
elements. Many methods based on physical or geometry optics havebeen investigated to measuring it. However, they are not appropriate to
test the altering focus position accurately, or test online. To investigate
the position altering of focus spot in high energy laser system, caused
by material thermal distortion or environmental turbulence, three array
image camera modes (plane mode, plan-mirror mode and wedge-mirrormode) are discussed in this paper. All of them are based on the theory
that the altering of focus position can be calculated from the variationof spot size on a certain detecting plan. Each of them has two splitting
elements installed vertically to divide the beam into series beams. In
this paper, not only the advantages but also the disadvantages havebeen investigated for each measurement model. As four key factors
for the array image camera, the complexity of calculation, the flexibilityof operation, the spots adhesion characteristic and the stray lighthave been respectively analyzed. Through the theoretical analysis,
software stimulation, wedge-mirror can works well in dynamical spotmeasurement for reducing spots adhesion and parasitic light effect. The
measure step of this design can reach one quarter of the focal depth;
when measure the system of f 1250mm, D 50mm, the accuracy canreach 0.0315mm.

8557-79, Poster Session

A practical approach for measurement of IR
optical system transmissivity
Yi Jian, Zhaoxin Pan, Shiyong Wang, Wang Yu, Luo Yixue,
Shanghai Institute of Technical Physics (China)
Transmissivity is a crucial parameter for an optical system, especially for
an infrared imaging system, which is commonly used for detecting andtracking dim target. NETD (Noise Equivalent Temperature Difference)is an important indicator for quality of an infrared FPA system, and it
is always related with the transmissivity of its optical system, which isdealing with energy transmission of the system. So it is necessary tomeasure the transmissivity when optical system is fabricated. However
it is usually not easily available as visible light optical system, when
the structure of IR optics is complex in particular. In this article, a newreliable method for measuring the transmissivity of optical system withcooled infrared detector is introduced. The principle of measurement isbased on Etendue conservation and luminance (radiance) conservation
when light travels through an ideal optical element. We put aLambertian blackbody source attached at the cold stop of IR detectorof under testing system, and get the grey-scale value of axis point ofdetector. Afterwards we put on the optical system for the detection
and calibrate the optical path for imaging system. Then we put theLambertian blackbody source at the position of entrance pupil of opticalsystem, and get the grey-scale value of axis point of detector again.
With proper calculation with these two grey-scale value, we could get
transmissivity of this optical system. A ray tracing simulation is made toshow the result for supporting correctness of this approach. A highaperture Lambertian blackbody source is required for the embodimentof this measurement.

8557-81, Poster Session

The distortion analysis and correction of
two-dimensional scanning system in laser
differential confocal microscopy
Chao Gao, Dali Liu, Weiqian Zhao, Beijing Institute ofTechnology (China)
Laser differential confocal technology is applied to lots of fields
as an important way of analysis and measurement for its highresolution imaging capability, unique section imaging capability andmulti-parameter capability. Because of its zero vision field imaging,differential confocal technology needs a scan system to image. For its
high-response frequency and fast positioning speed, two-dimension
vibrating mirror scan system is applied to laser differential confocal
microscope system. According to the structural characteristics of
two-dimension vibrating mirror scan system, this paper implements
systemic research and analysis. In this paper, based on the thin-lensimaging principle, the mathematic model of two-dimension vibrating
mirror scan system is built to achieve coordinate tracing of the scanbeam and it is found that the scan plots in scanning plane is distributed
unevenly, and there are two kinds of distortion, the nonlinear distortionand the pillow-shaped distortion, which will cause the image compress
in two dimensions. In order to correct the distortion, this paper
proposes an inverse-function method, and verifies the effectively of themethod by Matlab simulation of the system. The provided method canbe operated simply and understood easily, can be applied to largescale calculation correction, which provides an effective way to solve
the distortion problem of two-dimension vibrating mirror scan system.

8557-83, Poster Session

Research on the key parameters influencing
the anti-vibration capability of timefrequency-domain interferometer
Fanghua Zhang, Qun Hao, Yao Hu, qiudong zhu, Beijing

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Conference 8557:
Optical Design and Testing V
Institute of Technology (China)
Phase-shifting interferometry is a non-contact precise measuringmethod for optical surface, but it is highly sensitive to external
vibrations. In this paper, a time-and-frequency-domain anti-noise
phase-shifting interferometry is used to eliminate the effect of vibrations
and improve the precision of measurement. In this measuring system,a large number of phase-shifting interferograms are captured. The
temporal intensity array from each pixel is transformed into frequency
domain. A series of phase is obtained by frequency spectrum analysis.
A linear fitting of the phase series produces the result of original
phase. After unwrapping operation, the profile of the testing surface isreconstructed.
The paper focuses on an experimental system for testing the antivibration ability of the measuring method. In this system, the laser
is both the source and the phase shifter whose wavelength can be
modulated by current, and the displacement of the reference mirror
propelled by a PZT is used to simulate the environment vibration. A
stepped plane mirror is measured. During the measurement, each of
the parameters, such as the number of sampling frames, sampling
frequency and phase shift frequency, is assigned different values.
The testing results are compared with that from a ZYGO phaseshifting interferometer. By analyzing the comparative results, the lawof the parameters’ influence on system anti-vibration capability canbe obtained. According to the law, the optimization parameters canbe determined so that the system has the maximum anti- vibration
capability.

8557-84, Poster Session

Study of partial coherence measurementof the illumination system in excimer laser
lithography based on CCD image sensor
Xiaoyong Liu, Sichuan Univ. (China) and Shi Hezi Univ. (China);
Yiping Cao, Sichuan Univ. (China)
Rapid measurement of the partial coherence is very useful forprocess engineers to optimize the performance of exposure tooland process condition in optical lithography. In this paper,a novel
method of the partial coherence measurement based on CCD image
sensor is proposed. A pin-hole is located at the reticule such thatthe effective source is imaged through the pin-hole via the lens
onto the photosurface of CCD camera. Using the simple encircled
energy convention, the partial coherence can be calculated throughMatlab when the effective source is captured by CCD. This researchanalysed the parameters of the main components of the measurement
system, we mainly study the positioning accuracy along the verticaldirection, and the position variation of the spot caused by straightness,parallelism of the mechanical platform and the telecentricity of theillumination system.
The paper presents the statistic results and the sensitivity of themeasurement system under conventional illumination and kinds ofoff-axis illumination modes. All of the simulation results have proved thefeasibility and availability of the proposed method.

8557-86, Poster Session

The measurement schemes of PSF of Star
SensorXu Yao, Beijing Institute of Technology (China)
In order to measure the MTF of optical system, we should first get thePSF of optical system, then we get MTF through Fourier transform.
Based on the influences from the shape of star image and the energy
distribution to precision, we analysed the schemes of measuring PSF
and concluded that if the purpose of the PSF which is owned to bemeasured is different from the PSF which is used in the measurementof MTF, we will have different measurements. In theory, the smaller

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the detector is, the more precision the result is. As to the PSF of Star
Sensor, we will get the highest precision when we choose the schemeof simple scan in principle. However, while adopt photoelectronic
detector to detect it directly which is based on the method of sub-pixel
interpolation is a compromised scheme. So, in the consideration of the
precision of measurement, we should choose the scheme of arrowhead
simple scan.

8557-87, Poster Session

Study on the sub-aperture stitching method
Zhengnan Liang, Weirui Zhao, Guangyu Pan, Rong Li, Beijing
Institute of Technology (China)
Sub-aperture stitching is a virtual method for measuring large aperture
optical Components with low cost and high resolution by a small
aperture interferometer.
In this thesis, the theory of sub-apertures titehing15investigatedfirst,
including selection of stitching modes and setting of the number of
sub-apertures .Secondly, getting the interference fringe of the measured
surface through acquisition, using the extracted feature matching
points on different sub-aperture unwrapping the phase map stitchingprocess, using the Zernike fitting to obtain the measured surface fullbore surface information. under the premise of early positioning byusing instruments, reuse of the characteristics of the areas of the mirror
for precise positioning, And correctness of the Program is validated bysimulation. A platform is established for sub-aperture stitching test, andthen the experimental stitching that test the 100mmx100mm opticalcomponent by five Planar sub-apertures is Performed. Gives the resultsof contrast stitching and full aperture detection. Finally, experimental
research is conducted on the influence of stitching accuracy by subaperture overlapping area and stitching modes. The results show that
increasing the sub-aperture overlapping area can enhance the stitching
accuracy when the number of sub-apertures is unchangeable, andserial stitching is better than parallel stitching at controlling the stitching
accuracy.

8557-88, Poster Session

Smile effect detection for dispersive
hypersepctral imager based on the doped
reflectance panel
Jiankang Zhou, Soochow Univ. (China); Xiaoli Liu, Jiaozuo
Institute of Technology (China); Yiqun Ji, Yuheng Chen, Weimin
Shen, Soochow Univ. (China)
Hyperspectral imager is now widely used in many regions, such as
resource development, environmental monitoring and so on. The
reliability of spectral data is based on the instrument calibration.
The smile, wavelengths at the center pixels of imaging spectrometer
detector array are different from the marginal pixels, is a main factor
in the spectral calibration because it can deteriorate the spectral data
accuracy. When the spectral resolution is high, little smile can result in
obvious signal deviation near weak atmospheric absorption peak. The
traditional method of detecting smile is monochromator wavelength
scanning which is time consuming and complex and can not be usedin the field or at the flying platform. We present a new smile detection
method based on the holmium oxide panel which has the rich ofabsorbed spectral features. The higher spectral resolution spectrometerand the under-test imaging spectrometer acquired the optical signal
from the Spectralon panel and the holmium oxide panel respectively.
The wavelength absorption peak positions of every column pixels are
determined by curve fitting method which includes Gaussian model
simulation and spectral convolution. The iteration strategy and Pearson
coefficient together are used to confirm the correlation between themeasured and modeled spectral curve. The present smile detection
method is posed on our designed imaging spectrometer and the resultshows that it can satisfy precise calibration requirement of high spectral
resolution imaging spectrometer.

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8557-89, Poster Session

Error and compensation of Non-polarization
Splitting Prism(NPBS) in single frequency
laser interferometer
Yong Wei, Jun Yang, Harbin Engineering Univ. (China)
An online compensation method of non-polarization splitting
prism(NPBS) error in single frequency laser interferometer is presented
in the paper. Single-frequency laser has been widely used in the fieldof nano-vibration measurement interferometer for its high accuracy,
wide measuring range , and less optical components. We study theeffect of polarization characteristics of NPBS with different incident
conditions, establish online performance detecting system to study
NPBS. Using this system we also study the effect of reflected additional
phase of NPBS to single frequency laser interferometer. Changing thelocation of quarter-wave plate in the interferometer can compensate
the additional phase shift caused by the non-ideal of NPBS devices.
But this method will lead to the rotation, of polarization azimuth andultimately make the output signal contrast decrease. Adding a halfwave-plate in optical path to joint with quarter-wave plate for thecompensation of NPBS additional phase shift, which improves contrast
ratio of interference signal and restrains nonlinear errors of single
frequency laser interferometer. The results indicate that the method
can effectively compensate polarization error of NPBS, improve thequality of interference signal and raise measurement resolution ofinterferometer. Therefore, the method can be widely used in many fields
such as the investigation and preparation of nanometer high-precisionlaser interferometer.

8557-90, Poster Session

Measurement of physical polarization
parameters by system estimation with leastsquare optimization
Tao Liu, Chunhua Wang, Li Li, Haiyang Zhou, Shenfei Zhang,
Shanghai Univ. (China)
In this paper, we propose to obtain physical polarization parametersof optical devices directly by solving nonlinear equations with leastsquare best-fit optimization, instead of decomposing PP parameters
form the Mueller matrix measured in advance as previous works did.
The proposed scheme is based on the idea of system estimation, where
physical polarization parameters are regarded as the systematicalparameters to be estimated by using the measured input states ofpolarization and output states of polarization. The system estimation
method performs conveniently in obtaining the polarization parametersof the device under test. Besides, the states of polarization involved inestimation are not restricted on special ones, therefore a polarization
state generator simply consisting of a polarizer followed by a rotatingwave-plate is used to generate states of polarization for estimation.
Simulations based on MATLAB are done and the results show that
better estimation precisions can be obtained by involving morestates of polarization in estimations. More comprehensive results
are obtained by employing system estimation in our simulation. An
experiment to approve our simulation is demonstrate, which is mainly
constructed with a commercially available polarization state analyzer
and a polarization state generator which is comprised simply by alinear polarizer and a rotatable wave-plate. As a sample, the physicalpolarization parameters of a polarization controller is measured and theestimated errors is within 0.0011~0.01 for all parameters.

8557-91, Poster Session

Evaluation of parallel phase-shifting digitalholography by photon counting method
Lin Miao, Kobe Univ. (Japan); Kouichi Nitta, Osamu Matoba,

Kobe University (Japan); Yasuhiro Awatsuji, Kyoto Institute ofTechnology (Japan)
Parallel phase-shifting digital holography (PPSDH) is one of promising
methods to obtain instantaneously three-dimensional (3D) information.
The complex amplitude of an object wave is extracted from a patternedinterference distribution and then the reconstruction of the 3D object is
implemented in a computer by numerical Fresnel propagation or otherpropagation method. In the measurement of fast phenomenon of a 3D
field, the detected power will be decreased. In this paper, we evaluate
numerically the number of photons to be required for fast 3D object
measurement in PPSDH. In the numerical evaluation, a two-dimensional
image with a random phase distribution is used. This random phase
distribution increases the sensitivity of reconstruction distance. Photon
counting method is applied to obtain the patterned interference
distribution under weak illumination. The number of photons at eachpixel in an image sensor is generated from Poisson distribution. Theinterference pattern obtained by the photon counting method isprocessed by PPSDH and then the reconstruction is implemented
by numerical Fresnel propagation. The error of the amplitude and thephase distributions are evaluated by changing the number of photons.
This numerical evaluation gives us the minimum number of photons forthe fast measurement of PPSDH.

8557-92, Poster Session

The effect of temperature characteristic of
Faraday rotator to passively demodulated all
optical fiber current transformers
Yuekun Wang, Zhengping Wang, Shuai Sun, Harbin Engineering
Univ. (China)
In order to move signal detecting point to the most sensitive position
and improve the immunity of the system at the same time, the scheme
named passively demodulated all optical fiber current transformer(AOFCT) inserts a Faraday rotator of 22.5° rotation angle between fiber
retarder and leading fiber. To improve the performance of this type of all
fiber current transformer, after considering the temperature features of alarge proportion of Faraday crystals, the effect of the Faraday rotator’s
temperature properties on temperature stability of the passively
demodulated AOFCTs are theoretically analyzed and numericallycalculated. The results show that the errors induced by the Faraday
rotators are beyond the requested values in the International Standard
IEC 60044-8:2002 of International Electrotechnical Commission (IEC)and the State Standard of P.R.China GB/T 20840.8-2007. Finally, tosolve this problem, some possible solutions are suggested.

8557-93, Poster Session

Cyclops opening-up fiber for real-time
fluorescence sensing
Yi Yang, Donghua Univ. (China); Guanjun Wang, Key Laboratoryof Instrumentation Science and Dynamic Measurement (Ministryof Education) (China); Jian Cui, Engineering Training Center,
Beijing University of Aeronautics and Astronautics (China)
Compared with traditional fluorescence-based microstructured fiber
sensors using filled structure, the opening-up microstructured fibers
have shown many advantages for real-time sensing. The design andtheoretical study about Cyclops opening-up microstructured fiber ispresent in this paper. In Cyclops fiber, a large asymmetry hole is placedin fiber cladding. A tri-hole design is adopted for fiber core to enlarge
the evanescent field interactions with measured material. This structure
is compatible with the traditional stack-draw processing. To makethe opening-up structure, chemical etching (with acid) or polishingmachining could be used for the asymmetry hole.
The opening depth and shape of large asymmetry hole is important

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Conference 8557:
Optical Design and Testing V
for real-time sensing response in Cyclops opening-up fiber.
The relationship between marching depth in cladding and fluid
concentration distribution at different time in evanescent field near fibercore is analyzed numerically based on incompressible Navier-Stokes
equations and finite element method (FEM). The results show that theconcentration distribution in evanescent field adjacent to fiber core
can reach the true value out of cladding below ten seconds by design
cladding structure appropriately. The field distribution of fundamental
mode and some cladding mode of Cyclops fiber without tri-hole core
and with different tri-hole are presented in this paper too. To analyze
the sensing error in distributed measurements, the difference in
effective index, dispersion parameter and confinement loss about two
fundamental non-degenerate modes of the Cyclops fiber are studied.
Cyclops fiber show good characters in these aspects comparedwith wagon wheel (WW) opening-up fiber. In order to evaluate theperformance of sensing based on Cyclops opening-up fibers weadopted the modal power fraction (PF) within the sensing region andthe effective modal area (Aeff) and the fluorescence capture fraction(FCF). The results show the Cyclops opening-up fiber is a competitive
candidate for real-time fluorescence sensing.

due to its fast response time. It has been used widely in industrial andenvironmental fields. But when applied DOAS to continuous emission
monitoring systems (CEMS) such as in power plant, the differential
absorption characteristics of pollution gases will change greatly owing
to the flue gas is often with high temperature and high dust. This willbring the influence on the detection results.

8557-94, Poster Session

This article mainly aims at the temperature effects for SO2 differential
absorption cross section in UV region by recordings of spectra ina heat-pipe cell. The results show that the differential absorption
properties change dramatically with temperature. The differential
absorption peaks in the region of 280-320nm decrease with theincrease of temperature while the valleys will increase. So the entire
differential absorption cross section decreases with the increaseof temperature, but no wavelength drift and differential absorption
structure change appear with temperature. By measuring the differential
absorption cross section of ten obvious peaks at different temperature,
it is found that the reduction amplitude at different wavelength peak isvaried. When the temperature rises from 300C to 3900C, the relativechange of the differential absorption cross section peak value at
304.48nm is 60.88%, while it can reach 94.41% at 292.54nm. Thisshows that it is necessary to consider the temperature effect in theapplication of DOAS method for measuring the flue gas SO2, otherwise
very big measurement error will be produced.

Radiation distribution measurement forforest plant canopies tracing

8557-96, Poster Session

Xue-fen Wan, North China Institute of Science and Technology(China)A high-precision method and its
implementation of measuring spatial azimuth

Plant canopies in forest have distinct architectural elements such astree crowns, whorls, branches, shoots, etc. Since these structuresdictate the spatial distribution of leaves, the traditional random
assumption can’t satisfy Leaf Area Index (LAI) and the Fraction of
Photosynthetically Active Radiation (FPAR) measuring with highprecision, which are important biophysical parameters required inmany ecological and climate models. To obtain precise canopies
characteristic, the radiation distribution in forest gap should be
tracing. In this paper, a low-cost multi-node method for forest gap
radiation distribution synchronous measurement is present. It provides
distributed working parameters collecting for each tracing-line. Anda Zigbee wireless network is imbedded for communicating between
measuring node and host computer.

Zhiyong Yang, Zhaofa Zhou, Zhili Zhang, Xi’an ResearchInstitute of High Technology (China)

Using the solar beam as a probe, the measuring nodes collect radiation
distribution in forest gap. Each radiation spike is converted into gap sizevalues to obtain a gap size distribution. Low-cost photodiode (FDS100 in our design) is introduced for radiation spike tracing. A Microchip
PIC16F877 MCU is employed for radiation measuring and Zigbee ineach node. The collected data is sent to central station by Zigbee
wireless network. Solar radiation spike data and other environment
parameters (Temperature and Humidity) are forward to host computer.
Host computer get potential relationship in tracing-line LAI and FPAR
and compute them in long-term through Chen and LeBlanc TRAC
theory. A multi-node measuring theory developed from TRAC method
is also presented. Instead of tracing-line measuring, an arc nodes
installation according to Zenith angle is more efficient for rarefactionarbors such as Banyan and Poplar. An experimental setting with 3
nodes and host computer is tested. The experimental results show
our design could be a competitive candidate for radiation distribution
measurement for forest plant canopies tracing.

8557-95, Poster Session

Temperature effect of SO2 ultraviolet
differential absorption
Guiyin Zhang, Haiping Li, Haiming Zheng, North China ElectricPower Univ. (China)
The technique of differential optical absorption spectroscopy (DOAS)
can achieve the real time on-line monitoring of gaseous pollutants

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The spatial azimuth measurement system based on magneto-optic
modulation polarized light, refers to measuring the spatial azimuth
between upper and lower instruments without mechanical connection
with the polarized light and Faraday effect, this technology will greatly
promote the growth of spacecraft docking and developments ofbiomedical and other fields. But the measurement precision of the
traditional system is low, and the measurement scale is narrow. In orderto improve the traditional system, a new method of calculating azimuth
directly was present for the first time.
The principle of the traditional system was analyzed, the signal frommodulator was filterred with the lowpass, and it was expanded with the
Bessel Function, then the signal from modulator was substituted with
the Bessel expression whose higher order terms was omitted, therefore
there must be signal truncation error, which has influence on the systemmeasurement effect.
In the new method, the signal from modulator did not need being
filtered, it was analyzed directly, and its character that there are
two extremums whose abscissa is an constant was detected. The
relationship between azimuth and the extremums was established, theextremums was sampling with the sampling integral circuit, and theeqution between azimuth and the extremums was established.
There are adding roots when solving the eqution, in order to omit
the adding roots, the extremums was analyzed, and the relationshipbetween the number of extremum and the root of eqution was
detected, then the rule how to omit the adding roots, which is basedon the number of extremums was present, and the model of measuring
azimuth based on arc tangent function was acquired. At the same time,the measurement scale of azimuth was widened as the double angle
formula was cited.In order to calculate the arc tangent function in themodel with hardware, the method of looking-up table was introduced,
and the appropriate table according to the system measurement
precision was designed. At last the realization scheme of the new
method was finished. The measurement precision and scale of the
new method in the paper was analyzed with simulation calculation,
simulation results show that the measurement precision of the new
method is higher and measurement scale is wider, it provide a reference
to measuring spatial azimuth in wider scale and high precision, and it
has an important theoretical guiding significance.

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8557-97, Poster Session

Design and optimization of chopper basedon Labview
Guo Li, Capital Normal Univ. (China); Xiaolei Wang, Ministryof Industry and Information Technology (China); Lichun Feng,
Cunlin Zhang, Capital Normal Univ. (China)
Chopper is widely used in optical system to produce a series of
optical pulses which has particular shape and frequency. A chopper
system always has two parts: modulation plate and control box. A
tiny photoelectric switch detects the modulation frequency, and thefrequency is transmitted to control box by voltage signal. In the control
box, detected frequency and target frequency make a comparison.
Then a feedback signal is transferred to motor to adjust the rotate
speed of modulation plate. With this feedback system, modulation
frequency keeps approaching to target frequency and finally reaches
it. Now the price of choppers in the market ranges several hundreds toseveral thousands RMB, depending on its quality. This paper presents away to make a simple chopper based on Labview. Labview and NI DAQ
are widely available in universities. So with this method chopper system
can be easily constructed for temporary use. NI DAQ uses countertools to detect the frequency of modulated laser and produce several
feedback signal to drive the location and rotate speed of modulation
plate, which leads to the change of modulation frequency and duty. In
this sense, NI DAQ plays the role of control box. The program which
drives NI DAQ is edited by Labview. Labview use various frames andicons as programming language, instead of tranditional code. With thispoint, the program can adjust to different use and it has an advantage
of flexibility. This paper can provide a reference for experiment work in
optics and other natural science.

8557-98, Poster Session

Technique of measuring single grating
incremental angle
Yu Xiao, Changchun Univ. of Science and Technology (China)
This paper discusses a new method of measuring incremental angle,
which uses an arranged matrix of a narrow slit photoelectric cellaccording to certain logic phase combination replacing the fixed gratingin the grating pair. The measuring operation can be accomplished by
the coordination to replace between the coder disk and the arranged
matrix of the narrow slit photoelectric cell. Thus, there is no need of
considering the gap between the slit and the coder disk. The sensibilityof the incremental photoelectric encoder to the vibration and theprecision requirements of the spars are deduced. Thus the contrast
degree of the Moors fringes is enhanced, the subdivision precision isincreased and finally the measuring precision and the Stability are all
increased.

8557-99, Poster Session

Planar alignment sensor based on Rayleighinterference in two wavelengths
Yao Hu, Beijing Institute of Technology (China)
Precise alignment of planar optical element is common in industry
or scientific research. Generally, autocollimator can help solve theparallelism adjustment between planes. As to coplanar alignment ofplanes, such as mirrors or gratings, interferometer can be used toremove the angular or positional error, and displacement transducers
are often used for locking the coplanar condition. In this paper, a planaralignment sensor based on Rayleigh interference in two wavelengths
is proposed. It can conduct parallelism and coplane alignment at thesame time. Two beams of monochromatic probing lasers from thesensor point normally to the two mirror reflection planes to be aligned.

The reflective beams carrying the angular information back to thesensor are focused by a lens to form a Rayleigh interference patternat the focal plane. Four-quadrant detector picks up the pattern andoutputs angular adjustment signal according to the rotational-symmetryof the pattern. Monochromatic probing laser in another wavelength cantell the coplanar status from the axial-symmetry of the pattern. This issimilar with dual-wavelength interferometer. Demonstration experimentshows that the sensor can help achieve angular alignment accuracy
within 2 arcsecond and coplanar accuracy of 0.1 micron. With a groupof split-image and beam merging prisms, the probed positions on thetwo surfaces can be adjusted so that the sensor is flexible. This sensor
has prospect in industrial online alignment and monitoring.

8557-24, Session 6

Advances in optical design and optimizationof miniature zoom optics with liquid lenselement (Invited Paper)
Yi-Chin Fang, National Kaohsiung First Univ. of Science andTechnology (Taiwan)
Abstract: An optical design of 2X optical miniature zoom lens withliquid lens elements and optimization method: discrete lens groups
shifts (DLGS) has been presented in this research. Two liquid elements
are applied to minimize the overall length of zoom optics. Moreover, acompensative optimization method with assistance of Genetic Algorism
is introduced in this research with a new concept of DLGS, which
not only solve the complicated problem of liquid optics itself but also
improve the performance of optics. Genetic algorithms (GA) written in
CODE V plays the role at finding out the appropriate parameters suchas curvatures, thicknesses, glass materials and etc. Besides, one tablewith great lens groups shifts by GA would be created to move thelens groups on the optimal positions of different zooms. As a result,the DLGS optimization method associated with the GA optimization
improve the zoom lens performance averagely 40% better than
traditional ones.

8557-25, Session 6

Ultra-wide to mid-wide angle 3X zoom andfocus adjustable lens design for industrial
video endoscope
Dongmin Yang, GE Inspection Technologies (United States)
Optical zoom lens design for industrial video endoscope faces big
challenges in stringent compactness requirement in both diameterand rigid length dimensions, as well as working in harsh environment
such as high temperature so that liquid lens is not an option. Market
is strongly demanding industrial video endoscope with optical zoom
and focus change capability for better imaging performance at different
desired FOV (Field of View) and focus distance. No such product has
been commercialized yet. Once it succeeds, it could provide hugebenefits for customers to improve inspection quality and productivity.
A 3X continuous optical zoom lens design with short focal lengths ispresented in this paper. It is capable to change FOV from ultra-wide
angle as 120degrees to mid-wide angle as 40degrees. At any zoom
position, the focus distance is capable to change from infinity to as
close as 5 mm. The whole lens train has max diameter of 4mm, andoverall length of 14mm, which makes it practical to be integrated into
the mainstream 6mm industrial video endoscope. Image quality in termsof contrast and resolution satisfies or significantly better than today’s
existing commercial 6mm video endoscope. The design has also
considered cost and product ruggedness requests.

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Conference 8557:
Optical Design and Testing V

8557-26, Session 68557-28, Session 6

Optical image stabilizing technique based on
deformable mirror zoom system

Designing an all-reflective long focus andlarge field-of-view optical system withfreeform surface

Yuhua Jiang, Qun Hao, Beijing Institute of Technology (China);
Xuemin Cheng, Tsinghua Univ. (China)
Zoom lens is a kind of system whose focal length can be continuously
changed, which keeps a stable image plane and a good image quality
in zoom process. It has played a significant role in areas such as
aerospace and military imaging systems for its quick, continuous target
detection and flexible image motion compensation ability. This paper
presents a method that uses a deformable mirror in the optical designin order to achieve a quick response, optical image stabilizing (OIS) andminiaturization zoom lens, improving its system performance.
This paper developed the OIS scheme for an off-axis three-mirror
anastigmat. The deformable mirror was designed to correct the image
blurring and degradation, as carrier movement in the system makes
the relative motion between the imaging optical axis and the object.
Here we used a two-configuration system before and after motion
for the same point target in object. The first configuration is set as
carrier motionless and the second configuration tilts a small angle
relative to the first one. The secondary mirror uses a deformable mirror
as corrector mirror. Then by tracing a set of rays data, calculate thesurface parameters of the deformable mirror. Change the shape of thedeformable mirror to make the image plane of the second configuration
approach the image plane of the first configuration to produce image
plane decentration. At the same time, it can correct defocus, image
plane tilt and aberration. Finally, we can achieve OIS for the zoom
system based on the deformable mirrors.

8557-27, Session 6

Optical system design for a short-wave
infrared imaging spectrometer

Qingfeng Wang, Dewen Cheng, YongTian Wang, Yue Liu,
Beijing Institute of Technology (China)
Freeform surface has many advantages in optical design over theconventional spherical or aspheric surface. The appropriate applicationof freeform surface can not only help to achieve high imaging
performance but also make the system light-weight and compact.
All-reflective optical system has been widely usedin deep spacedetection.We studied the application of freeform surface in all-reflective,
off-axis optical system and infrared, off-axis optical system wasdesigned which has long effectivefocal length and large field of view.
The freeform surface was employed to get better performance andsmaller system size and weight.
The starting point of the design was calculated by the theory ofaberration and property of conic. After that we optimized the starting
point using the strategy of successive approximation optimization
which can reduce the difficulty of optimizing process. Based on thetheory of aberration, the best position of freeform surface in the off-axis
system was analyzed. At last, a four mirrors optical system with long
EFL and large field of view was designed.The system consists of threeconic surfaces and one freeform surface. The effective focal length andfield of view are 4.5m and 3°, respectively.The volume is as small as
0.5mx0.5mx0.7m.The MTF at Nyquist frequency is close to diffraction
limit.
By taking consideration of the fabrication and align difficulty of thefreeform optical system, we carried out a comprehensive tolerance
and alignment analysis. Based on the result of analysis, a process ofalignment was proposed to ensure the system can be fabricated in low
cost and high performance.

Han Huang, Xiaotong Li, Zhaofeng Cen, Zhejiang Univ. (China)

8557-29, Session 7

A short-wave infrared (SWIR) imaging spectrometer with all reflective
elements was designed. The imaging spectrometer is composed of
an off-axis three-mirror anastigmatic (TMA) telescope and an Offner
spectral imaging system with convex grating. Based on the geometrical
optical imaging theory of coaxial three mirror system, the initialstructural parameters of TMA telescope were determined. Designed
and optimized with ZEMAX software, the off-axis three mirror system
had a spectral region from 1.0 to 2.5um, focal length of 343.56mm,
relative aperture of 1/3.5, field of view angle of 5°x0.1°, and modulationtransfer function approaching to diffraction limit. Using the image
space NA of the telescope as the object space NA of the spectrometer,
determining the initial configuration by analyzing the astigmatic featureof Offner spectroscopic system, a SWIR Offner spectral imaging
system was designed and optimized. Attaching the telescope to thespectrometer, the optical design of a SWIR imaging spectrometersystem was finally completed after further optimization. The system
has a slit of 30mm, a spectral resolution of 10nm, a smile or keystoneof the slit spectral image less than ten percent of a pixel size, and its
imaging quality approaches to diffraction limit. The theory of design andthe analytical approach that the paper referred to are relatively simple
and the design method used is also applied to other spectral region. In
addition, ZPL language of ZEMAX is used to simplify the procedure. It
is a good way for designing similar imaging spectrometers of excellent
quality in a short time.

Measurement of the mirror refractive
spectrum of typical roughness surface in theultraviolet band (Invited Paper)
Lu Bai, Zhensen Wu, Yanhui Li, Xidian Univ. (China)
The reflect light of a surface contains many features of the surface. It is
usually used as a powerful tool for process in situ or ex suit monitoring
because of its non contact and non destructive nature. Recently, withthe development of multi-band target detection, the requirement of
the measurement data in the multi-band is necessary to analysis thescattering properties of a target. But lots of paper adducible discussed
the measurement or model method in the visible to infrared band. Few
references discuss about the measurement results of the surface in theultraviolet band. As there has been increasing interest in the study ofscattering and reflective properties in ultraviolet band (200 to 400 nm).
Such as ultraviolet space objects detection and subsurface defects
short wavelength monitoring in semiconductor industry etc. Researcheson the scattering properties in the UV band are necessary. Ellipsometry
is a well-known and an extremely sensitive characterization techniquewhich may be used to determine a lot of characteristics of the surface,such as the specular reflection and transmission properties fromsurfaces and coatings.In this paper, the experiment measuring system
is introduced. Scatter measurements of some typical samples in the
UV band are performed by using the ellipsometry WVASE 32 madeby J. A. Woolam Co. Inc. The mirror-direction refractive measurement
results obtained by ellipsometer are analyzed and compared with themeasured data from spectrometer.
And these kinds of researches about measuring and analyzing of typicalroughness samples in ultraviolet band have significant meanings in a lotof related fields.

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Optical Design and Testing V

8557-30, Session 78557-33, Session 8

The measurement of optical reflector withcomplex surface using nano-CMM

Enhancing the performance of coaxial
three mirror anastigmatic optical system by
wavefront coding (Invited Paper)

Zhichao Wu, Tong Guo, Jinping Chen, Xing Fu, Xiaotang Hu,
Tianjin Univ. (China)
Among variety of methods to measure complex surfaces, coordinate
measurement is widely used in reverse engineering and measuring
complex topography. In this article, a coordinate measuring system
based on 3D tactile probe is used to measure a high precisionsine surface array. This system can measure complex surface withresolution of 1nm, 3D uncertainty less than 50nm, measuring range of
25mmx25mmx5mm. The probe named Gannen XM can measure themovement of the tip in 3D, so it is more accuracy than trigger probeand 1D analog probe. The probe also applies 3D uncertainty of 50nm
and measuring force less than 1mN. The positioning system is basedon Nano Measuring Machine (NMM), it uses three interferometers tomeasure the displacement of the stage with 0.1nm resolution and10nm uncertainty. The tip of the probe is at the point that the threeinterferometers’ measuring line intersect, so it can reduce the Abbeerror as small as possible. A signal acquisition module NI-USB6259BNC
is used to acquire the signal of the probe and became the main part of
feedback system. There is a sine array reflector sample with about 5
micrometer amplitude and we test it with our 3D coordinate measuringsystem. The result is compared with data of AFM and the course ofdeviation is analyzed in the conclusions.

Bo Li, Bing-Long Zhang, Beijing Institute of Space Mechanics
and Electricity (China)
Coaxial Three Mirror Anastigmatic(TMA) optical system is used in many
space based optical earth obsering satellites because it’s excellent
anti-astigmatic performance. Space onvironment distubances suchas thermal field change,vibration often causes optical elements to
deformation,tilt or position deviation. So the structure stability is oneof the key factor to influnce the actual performance when coaxial
TMA camera run on orbit. A coaxial TMA optical system is designed
and optimized that is insensitive to defocus and defoucus-relatedaberrations by adding a designed phase mask based on wavefront
coding method. A filter is developed based on wiener fliter which caneffectively restore the blure produced by phase mask and defocus andmagnify the image noise only a little.Finally,the actual performanceof opitmized imagin system is analyzed by the simulation. The resultshows that the fabrication and assembly tolerance of coaxial TMA
optical system is relaxed to 2 times,the depth of focus of system isextended to 15 times than before by using wavefront coding, and theimaging quality is almost unchanged, actual performance is enhanced.

8557-34, Session 88557-31, Session 7

Wave-front coded optical readout for the
MEMS-based uncooled infrared imaging
systemTian Li, Yuejin Zhao, Beijing Institute of Technology (China);
Xiaomei Yu, Peking Univ. (China); Liquan Dong, Beijing Instituteof Technology (China); Mei Hui, Beijing Institute of Techonolgy(China); Xiaohua Liu, Cheng Gong, Xuhong Chu, Beijing Instituteof Technology (China)
The uncooled optical readout infrared imaging system based MEMS
has become a researching hotspot. In the space limited system
pursuing integration, miniaturization and modularization, the adjustmentof optical readout part is inconvenient. This paper proposed a methodof wave-front coding to extend the depth of field of the optical readout
system, to solve the problem above, and to reduce the demanding for
precision in processing and assemblage of the optical readout systemitself as well.
This wave-front coded imaging system consists of optical coding anddigital decoding. By adding a CPM(Cubic Phase Mask) on the pupil
plane, it become non-sensitive to defocussing within an extended
range. The system has similar PSFs and almost equally blurredintermediate images can be obtained. Sharp images are supposed tobe acquired based on image restoration algorithms, with the same PSF
as a decoding core.
For comparing, we designed a traditional optical imaging system as
well, which had the same optical performance with the wave-front
coding one. Analogue imaging experiments were carried out, using
MATLAB, by calculating two-dimension convolution between the object
and the defocussing PSFs. One PSF was used as a simple direct
inverse filter, for imaging restoration. Relatively sharp restored images
were obtained. Comparatively, the analogue defocussing images of the
traditional system were badly destroyed.
Using the decrease of the MTF as a standard, we found the depth offield of the wave-front coding system had been extended significantly,
to which can never be achieved by any traditional imaging system.

Analysis of the silicon carbide applicabletechnique in the EO/IR telescope forspaceborne
Haengbok Lee, Agency for Defense Development (Korea,
Republic of)
The latest very high resolution optical sensors are WorldView-1 a GSD
of 0.45m is available, but also with QuickBird(0.62m GSD), GeoEye1(0.41m GSD), Pleiades-1(0.5m GSD), EROS-2B(0.7m GSD) andKompsat Series(Kompsat-1, -2, -3 : 6.6m, 1m, 0.7m GSD respectively)
as well as with the other new very high resolution optical space
imagery a topographic mapping is possible. The spaceborne telescopeassembly, which incorporates the primary mirror and secondary mirrors,
optical bench, and metering structure, must retain the alignment after
launch and during operation in space. A trend in spaceborne telescopes
has been an increase in collection area and in resolution. Both ofthese demands in performance require larger primary mirror aperturesizes. Since the primary mirror often dominates the mass budget of
the telescope, either of these options imply larger mass for the overallsystem. Major efforts in spaceborne telescopes have inspired researchin lightweight optics. Also, metering structure requires high stiffness,high dimensional stability and minimum obstruction of the telescope
aperture to get high quality images. Silicon Carbide(SiC) mirrors andstructures are becoming more important for high precision lightweight
optical applications in space. For space applications, mass density,
elastic stiffness and strength related properties are most important.
There are many SiC satellites which were applied Formosat-1,-2,
THEOS, Pleiades-2, STOP6, 7, Geo-Africa, ASNARO. This paper
describes trade studies that explore the structural views for thelightweight primary mirror and the metering structure as well as the sic
application in sub-metric class spaceborne telescope.

8557-35, Session 8

The effects of piston error on image quality
Jun Zhang, Weirui Zhao, Feng Yang, Beijing Institute ofTechnology (China)
The relationship between image quality and piston errors between

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Conference 8557:
Optical Design and Testing V
adjacent segments in synthetical aperture optical imaging system has
been studied. An active segmented cophasing imaging system witha high accurate optical adjustment and control in nanoscale was set
up for the study. A Zemax simulation model of the cophasing imaging
system was established. Under the condition of a monochromaticand a continuous spectrum halogen light being as the source of thesystem respectively, diversity piston error were introduced between
the segments and then the MTF correspond to each piston error
was calculated with the Zemax simulation model. The range of theintroduced piston error under each condition is from 0nm to 5000nm,
and the error step is 50nm. The MTF correspond to each piston error
was recorded, and the curves of MTF’s change with the change ofpiston errors were obtained and analyzed. Meanwhile the experiments
have been carried out with the active segmented cophasing imaging
system to research the relationship between the image quality and thepiston errors. The experimental results are coincident with the results
simulated by Zemax. The results of the experiments and simulation
show that the image quality of synthetical aperture optical imaging
system changes with the increase of the piston error between thesegments periodically if the piston error is smaller than the coherent
length of the light source used by the synthetical aperture imaging
system, and the image quality becomes the worst if the piston error isan odd multiple of p.

8557-36, Session 8

Optical design of multispectral sensor using
off-axis three-mirror reflective optics
Tianjin Tang, Huan Li, Beijing Institute of Space Mechanics andElectricity (China)

8557-37, Session 8

Design of a compact four-mirror opticalsystem with wide field-of-view
Aman Wei, Jun Chang, Beijing Institute of Technology (China)
During the development of science and the enhanced demand of
scientific research, the demand to optical design is enhancing everyday. The study of optical system with wide field of view is a branch of
optical design. Compared with the traditional optical system with wide
field of view, the reflective optical system had many advantages, suchas less weight and without chromatic aberration. The reflective opticalsystem is drawing more and more attention with the above referredto advantages. A method based on Seidel aberration theory to design
a four mirror optical system with wide field of view was mentioned inthis paper. In this method, Seidel aberration theory was studied in thefirst step, and the technical parameters of the system were got fromthe demands, then the technical parameters, such as the diameter ofentrance pupil and the field of view were substituted into the Seidel
aberration equations. Then we solved the equations with additional
limit, and got the initial parameters of system, for example the radiusof curvature of each mirror. The example in this article was a design ofa compact four mirror system with a field of view of 15°and F numberof 5. This example showed that the method based on Seidel aberration
theory to design a four mirror optical system with wide field of view iseffective and feasible. This kind of compact four mirror system with awide field of view can be applied to UV light, visible light and infrared
light multispectral imaging with the less weight and without chromaticaberration. It can be widely applied to many fields, such as remotesensing and electricity discharge detection.

al mirror, the light incidents into the TMA, then dichroic by the wedge
dichroic mirror, one part of the incident light is reflected by the dichroic
mirror to the visible and near infrared focal plane; another part of theincident light transmits the dichroic mirror and afocal relay lens to theshort and medium wave focal plane.
The optical system is composed of three reflective mirrors and five lenswith an F-number of F/4 for visible light channel and F/3 for anotherchannel, the focal length is 680mm and a field of view of 5&#61616;(CT) &#61620;1&#61616; (AT) for two channels , a working wavelength
range of 450~5000nm. The paper also analyses the selection of dichroic
schemes. The MTF of each channel at respective fields for multiple
wave bands are also given at respective Nyquist frequence, the MTF of
visible and near infared wave bands is over 0.7 at respective Nyquist
frequence 50lp/mm and over 0.5 for short and medium wave band atrespective 25lp/mm and 12.5lp/mm. The engineering feasibility of the
optical system is also analyzed based on the tolerance analysis, the
MTF of the camera is also forecasted at the end of the paper.

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Optoelectronic Imaging and Multimedia Technology II
Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8558 Optoelectronic Imaging and Multimedia Technology II

8558-1, Session 1

Zhang, Liu Tiegen, Tianjin Univ. (China)

Real-time interactive projection system
based on infrared structured-light method

An automatic seal identification method based on the edge difference
histogram is proposed. Differences between a sample seal (SS) anda model seal (MS) on geometrical characteristics, such as topologicalstructures, stroke width and stroke position, were wholly reflected byedge difference image. In this paper, edge difference is expressed
quantitatively as two parameters, distance between non-overlappedcorresponding edges and their lengths. Addition to positions and areasof non-overlapped corresponding edges, statistical property of points
on the edges is used to compute the two parameters. To eliminate
effects of noises and stamping conditions on the verification result,efficient edge difference that is closely related to the identification is
obtained according to the two parameters. A histogram on the productof the two parameters of the efficient edge difference is proposed toconstitute the input feature vectors of support vector machine (SVM).
SS is classified by SVM as true, false or doubtful. In Experiments,
4810 (2450 genuine and 2360 fake) seal imprints were verified, and thecorrect recognition rate is 99.42%. Moreover, the classification results
can be customized according to the requirements of users. When thefalse-acceptance error rate and the false-rejection error rate are both
required to be close to 0, the rejection rate is about 3%.

Xiaorui Qiao, Qian Zhou, Kai Ni, Yang Li, Guanhao Wu, Liang
He, Leshan Mao, Xuemin Cheng, Tsinghua Univ. (China)
Interactive technologies have been greatly developed in recent years.
However, most interactive projection systems are based on special
interactive pens or whiteboards, which is inconvenient and limits the
improvement of user experience.
This paper introduced our recent progress on theoretically modeling areal-time interactive projection system. The system permits the user toeasily operate or draw on the projection screen directly by fingers. The
projector projects infrared striping patterns onto the screen and CCD
captures the deformational image. We resolve the finger’s position andtrack its movement by processing the deformational image in realtime. A new way to determine whether the finger touches the screen
is proposed. The first deformational fringe on the fingertip and the first
fringe at the finger shadow are the same one. The correspondence isobtained, so the location parameters can be decided by triangulation.
The simulation results are given, and errors are analyzed.

8558-4, Session 1
8558-2, Session 1

A laser-based measurement system fortransparent surface forming
Mingyan Li, Xinzhu Sang, Yang Sun, Binbin Yan, Chongxiu Yu,
Beijing Univ. of Posts and Telecommunications (China)
In the traditional process, the transparent surface forming just simply
relies on the engineer’s experience to determine. However, the precise
requirements of modern industry stimulate us to find an accurate
judgment mechanism rather than manual. To achieve the high precision
measurement, this paper presents an optical measurement for the key
points of the transparent surface. This system has three modules, alaser, a CCD camera and a computer. They are in charge of exposure,receiving and processing respectively. Transparent surface is placed in
an enclosed space, growing slowly from low to high. The laser beam is
injected to the transparent surface, CCD receives it on the other side.
After passing through the transparent surface, the laser spot images on
the camera. Once we connect the camera with the computer, we cansee the image change in real time. When the transparent surface grows,
the shape of the spot will change accordingly. We detect the change tomonitor the height change of transparent surface.
Image processing includes several steps such as median filtering,binarization and ellipse fitting. We present a method to record thechange, from which we can calculate the effective axial length. The
performance of the algorithm is given. It can process ten images per
second, achieving the desired processing speed requirements. Aftermeasuring and analyzing large amount of data, the relationship between
the change of effective axial length and the height of transparent
surface is drawn. It can help us to control the growth of the transparent
surface better by analyzing the trends of the curve. By calculating, we
obtain the measurement error is 2.725%. The small error ensures theaccuracy of measurement.

8558-3, Session 1

Seal imprint verification using edge
difference histogram
Jin He, Tianjin Univ. of Technology and Education (China); Hao

A new 3D imaging lidar based on the highspeed 2D laser scanner
Chunsheng Hu, Zongsheng Huang, Shiqiao Qin, Xingshu Wang,
National Univ. of Defense Technology (China)
The research of the 3D imaging lidar is a key area in the field of 3D
information acquisition. Laser diode is widely used in 3D imaging lidars
because of its low price, small volume and easy usage. To enhance
the measuring speed of 3D imaging lidar and to obtain 3D images inhigh speed under static conditions, we proposed a new 3D imaging
lidar with a laser diode and a high-speed 2D laser scanner as thefundamental parts. The laser diode was used to output pulsed laser ofhigh peak power and narrow width. With the proposed new structure,
the laser scanner can scan fast in a 2D field by only one asymmetric16-plane rotating mirror. The characteristics of this scanner included
high speed scanning, large scanning field and simple structure. The
proposed 3D imaging lidar was mainly composed of a transmitter, alaser scanner, a receiver and a processor. The laser diode was one of
the most important parts in the transmitter. This paper introduced here
the composition and principle of each important part of the 3D imaging
lidar. Some experiments were implemented to evaluate the performanceof the lidar, such as scanning field, measuring precision, scanningspeed, image resolution and etc. The results showed its scanning fieldof about 26°?12°, its measuring precision of better than 5 cm (4 m
distance), its scanning speed of 30 frames per second and its image
resolution of 16?101. It can obtain a 3D image and an intensity image
for the given target at the same time.

8558-5, Session 1

A novel high-speed 2D laser scanner for the
3D imaging lidar
Chunsheng Hu, Dejun Zhan, Shiqiao Qin, National Univ. of
Defense Technology (China); Xingshu Wang, National Universityof Defense Technology (China)
The research of 3D imaging lidars is the key area in the field of 3D
information acquisition. Laser diode is widely used in 3D imaging
lidars because of its low price, small volume and easy usage. In order

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Conference 8558:
Optoelectronic Imaging and Multimedia Technology II
to enhance the speed of measurement in the 3D imaging lidar and toobtain 3D images in high speed under static conditions, we proposeda brand new high-speed 2D laser scanner used in the 3D imaging lidar
with a laser diode as a key element. This paper discussed the principles
and the characteristics of commonly used laser scanners, including
symmetric rotating mirror scanners, vibrating mirror scanners, ovalline scanners and double optical wedge scanners. We proposed here
an asymmetric 16-plane rotating mirror with a new structure, with theability to scan fast in a 2D field by only one rotating mirror. The principleof scanning and the structure of the rotating mirror were introduced indetail. With the use of this asymmetric rotating mirror, the scanner had
some advantages: high speed scanning, large scanning field and highreflectivity. This paper discussed the scanning speed and the resolutionof the scanner. Some scanning experiments had been carried out andthe results showed that the scanning speed of above 30 frames per
second, the scanning field of about 32°?12°, the vertical resolution ofeach frame of 16, the laser reflectivity of above 0.9. The proposed laser
scanner had wide applications such as groundborne, vehicleborne andairborne 3D imaging lidars.

conditions on the identification accuracy and makes the tracking target
unique in the wild circumstances.

8558-6, Session 2

Potential fingerprints detection using UV
spectral imaging

Compressive imaging based target locating
system for APT in FSO communication
Ping Wei, Jun Ke, Fen Wang, Beijing Institute of Technology(China)Conventional APT (acquisition, pointing, tracking) acquires 2D images
for target locating, and then uses the location to guild signal beam
direction for FSO (free space optics) communication. Each image
in APT is a bright spot with an all-black background. Therefore, it isspatially sparse and redundant. To reduce the redundancy and increasetarget locating speed, we study a compressive imaging based APT (CIAPT) system.
In a CI-APT system, linear combinations of object pixels, referred to as
features, are measured by a single detector. Hadamard projection isused for collecting features because of its simplicity for implementation.
Then from these features, objects are reconstructed with methods suchas OMP for target locating. Multiple sets of Hadamard vectors, such assorted and randomly selected vectors, are analyzed.
To demonstrate the idea, an experimental system using a 0.55’’ DMD
with XGA resolution is built. The DMD driver system is modified toincrease the data acquisition speed from 100 to 20K frames per
second. A LED is used as the movable bright spot in the all-black
background. Objects of size 256x256 and 768x768 are tested. For
a 256x256 object with the bright spot located at position (40, 30),
reconstructions are obtained using 256, 128, and 64 Hadamard
features. The estimated spot location are (39.56, 30.60), (38.43,
28.58), and (41.70, 25.68), respectively. It can be observed that after
compressing 256*256/64=1024 times, the CI-APT system still works
well for target locating. Additionally, in this work, main factors for theexperimental system error are analyzed.

8558-7, Session 2

Real-time identification and tracking of
infrared markers based on Kalman filter
Qiaona Xing, Dayuan Yan, Xiaoming Hu, Junqin Lin, Bo Yang,
Beijing Institute of Technology (China)
Automatic equipment transportation in the wild terrain circumstances
is very important in rescue or military. How to realize accurate tracking
of a guider is the key to completing the automatic walking for mobile
robots. But the existing identification methods are affected greatly
by ambient light or the non-unique feature in the environment.
Therefore, this paper presents an accompanying system based on
the identification and tracking of infrared LED markers which are fixed
on the guider’s back. This system overcomes the influence of light

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For the limitations of the global search, this paper presents a fast
infrared markers’ identification algorithm based on the Kalman filter.
the Kalman filter predicts where the infrared markers may appear in thenext frame by establishing motion model of infrared markers to reduce
the searching area of infrared markers,, which remarkably improves theidentification speed of infrared markers.
The flow of the system is divided into the following steps: (a)Obtainment of the images of the infrared markers by the camera; (b)Image processing; (c) The identification of the infrared markers; (d)Calculation of the centroid of the infrared markers; (e) Calculation of
the camera’s position; (f) Prediction of infrared markers’ area in the next
frame by the Kalman filter. Then the above 6 steps are completed in
the predicted area. The experimental results show that the algorithm
proposed in this paper is effective and feasible.

8558-8, Session 2

Wei Huang, Institute of Forensic Science (China); Zhichao
Yang, Zhejiang Police College (China); Xiaojing Xu, Insititute ofForensic Science Ministry of Public Secrurity (China); Jingjing
Guo, Institute of Forensic Science Ministry of Public Security(China)Spectral imaging technology research is becoming more extensivein the field of examination of material evidence. UV spectral imaging
technology is an important part of the full spectrum of imaging
technology. Due to the limitations of previous devices, most research
has focused on technology of the near-infrared light and visible light.
The study of ultraviolet spectral imaging technology is much fewer.
This paper summarizes the application of the results of UV imaging
technology in the field of evidence examination, explores the common
object of potential fingerprints of UV spectra characteristic for the
research objectives, which shows the potential traces of criminal using
the ultraviolet spectrum imaging method.
This paper finished the experiment contents of the ultraviolet spectrum
imaging method and image acquisition system UV spectral imaging
technology. The experiment of UV spectral imaging method obtains theimage set of the UV spectrum, and formats a pseudo-color images toshow the potential traces successfully by processing the set of spectral
images; UV spectral imaging technology explores the technology
method of obtaining the image set of ultraviolet spectrometer thoughultraviolet spectrometer and image acquisition system, and extensive
access to the UV spectrum information of potential fingerprints ofcommon objects, and study the characteristics of the ultraviolet
spectrum.
In this paper, the experimental UV spectral imaging method for
the UV spectral imaging technology provides a reference path topractical experience for future experiments. UV spectroscopic imaging
experiments explores a wide variety of UV reflectance spectra of theobject material curve and its UV spectrum of imaging modalities,
can not only gives a reference for choosing ultraviolet wavelength toshow the object surface potential traces of substances, but also gives
important data for the ultraviolet spectrum of imaging technology
development.

8558-9, Session 2

A real-time people counting system bydetecting human head-shoulder profile using
line structured light
Ping Wei, Jun Ke, Lizhong Wei, Beijing Institute of Technology(China)124A  
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People-counting is important for civilian security protection in crowded
places such as subway, train station, stadiums, or festival celebrationsites. Majority solutions to this problem are based on processing
surveillance camera images with sophisticate algorithms. In this work,a novel real-time people counting system is discussed by detecting
human head-shoulder profile using line structured light. Comparedwith image processing approaches, this system is cost-effective,
computationally simple, and has higher detection accuracy.
The system is assumed to be installed above an entrance/exit gatewith height roughly 2.5 meters. Several line structured light source are
spread over the width of the gate, which can be larger than 10 meters.
Each source is paired with a CCD camera having a vertically downward
view. Then, as people go through the gate, their head-shoulder profiles
are captured by the camera. However, instead of using grayscale orcolor information in the image to extract the profiles, we calculate thedepth of the line illuminated by the source from the line’s deformation
using range finding technique. Then, by correlating the obtained depth
signal with a reference human head-shoulder profile, the number of
persons passing through the gate is obtained. To avoid the overlappedfield of views between adjacent cameras, we expose the cameras andtheir paired light sources sequentially. Additionally, simply by using
another line structured light array, we can detect the direction of each
person passing through the gate.

8558-10, Session 2

Video fire detection based on three-state
hidden Markov modal and fractal dimension
calculation
Bo Lei, Zhijie Zhang, Chensheng Wang, Huazhong Institute ofElectro-Optics-Wuhan National Lab. for Optoelectronics (China)
Fire detection based on video surveillance is a very effective method
for large area outdoor fire prevention, but the unpredictable place andtime makes automatic fire detection a difficult problem. Many papers
adopt color based fire detection method, whose results depend greatly
on the camera’s chromatic rendition ability. Strict color match would
cause much false negative detection while loose match would evoke
many false positive alarms. We adopt a loose color selection to narrow
down possible fire areas, and use frame differential to confirm areas
where consequential fire detection should be performed. Pixels in thoseareas are put into a detection pool where every pixel’s temporal color
variations are analyzed. Then two three-state hidden Markov modals
are used. One is used to exam the brightness variations of those pixels
and the other one is used to exam the fire color likeness of them. Firecolor likeness of a pixel is measured by color difference from the firecolor which at first is a given default value and changes according
to the previous fire detection results. The results of these two exams
are combined with certain weights to determine whether those pixels
belong to fire regions. We use two methods to eliminate false alarms.
First one is to check the fractal dimension of detected fire regions,which is useful for some moving fire color like objects, such as wiggling
flag. The second one is to perform texture match for nearby fire regions
in consecutive frames, which is effective for fire texture like objects,
such as light yellow color hay. Experiments proved the promoted
method are suitable for real-time outdoor or indoor fire detection insurveillance videos.

8558-11, Session 2

Improvement of single-wavelength based
Thai jasmine rice identification with elliptic
Fourier descriptor and neural network
analysis
Kajpanya Suwansukho, King Mongkut’s Institute of Technology
Ladkrabang (Thailand); Sarun Sumriddetchkajorn, National
Electronics and Computer Technology Ctr. (Thailand); Prathan

Buranasiri, King Mongkut’s Institute of Technology Ladkrabang(Thailand)
Recently, we have proposed and developed a single-wavelength
spectral-imaging-based Thai jasmine (KDML105) rice identification
system that can distinguished KDML105 milled rice from otherunwanted rice varieties (e.g., CNT1, PTT1, and HPSL2) with a measured
average false acceptance rate (FAR) of 15.6%. To improve the overall
FAR in pinpointing the KDML105 milled rice, this paper, rather thanconsidering only the amount of fluorescent signal spatially distributedon the image of milled rice grains, analyzes the shape and size of theimage of each milled rice variety especially during the image thresholdoperation. The image of each milled rice variety is expressed as chain
codes and elliptic Fourier coefficients in terms of their semi-major axis,
semi-minor axis, and perimeter values. After that, a feed-forward backpropagation neural network model is applied, resulting in an improved
FAR of 11% in identifying KDML105 milled rice from the unwanted four
milled rice varieties. Other key features include adaptive learning ability
and ease of implementation.

8558-12, Session 2

Two-dimensional PCA-based human gait
identification
Jinyan Chen, Tianjin Univ. (China); Rongteng Wu, Minjiang Univ.
(China)It is very necessary to recognize person through visual surveillance
automatically for public security reason. Human gait based identification
focus on recognizing human by his walking video automatically using
computer vision and image processing approaches. As a potential
biometric measure, human gait identification has attracted more andmore researchers. Current human gait identification methods canbe divided into two categories: model-based methods and motionbased methods. In this paper a two-Dimensional Principal Component
Analysis and temporal-space analysis based human gait identification
method is proposed. Using background estimation and image
subtraction we can get a binary images sequence from the surveillance
video. By comparing the difference of two adjacent images in the gait
images sequence, we can get a difference binary images sequence.
Every binary difference image indicates the body moving mode during
a person walking. We use the following steps to extract the temporalspace features from the difference binary images sequence: Projecting
one difference image to Y axis or X axis we can get two vectors. Project
every difference image in the difference binary images sequence toY axis or X axis difference binary images sequence we can get two
matrixes. These two matrixes indicate the styles of one walking. Then
Two-Dimensional Principal Component Analysis(2DPCA) is used totransform these two matrixes to two vectors while at the same time
keep the maximum separability. Finally the similarity of two humangait images is calculated by the Euclidean distance of the two vectors.
The performance of our methods is illustrated using the CASIA Gait
Database.

8558-13, Session 2

Feature point tracking for incomplete
trajectories with multi-view constraint
Kun Pen Wang, Beijing Institute of Tracking and
Telecommunication Technology (China)
Feature points tracking is a standard task of computer vision
with numerous application in navigation, motion, understanding,surveillance, scene monitoring, and video database management. In
an image sequence, moving objects are represent by a set of featurepoints detected prior to tracking or during tracking. As local image
properties of feature points are often unstable, points are treated as
indistinguishable, and kinematic constraints are solely used to establish
the correspondences. This task, called the correspondence problem,

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Conference 8558:
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becomes a complicated problem for a dense set of unrelated featurepoints.
Methods of feature point tracking are researched mainly concerning
image sequence from single camera, and the approaches try to recover
real 3D motion from its’ 2D projection which is an incomplete problem
and have limited capabilities in handling incomplete trajectories.
The concept of a cooperative multi-camera ensemble, informally a‘forest’ of cameras, has recently received increasing attention fromthe research community. The problem of associating objects acrossmultiple cameras with overlapping fields of views has been addressedin a number of papers, but most of the methods are based on Bayesianframework, which are complex for practical application. Furthermore,
Dynamic scenes with multiple, independently moving objects should beconsidered where feature points may enter, temporarily disappear, andleave the view field.
A new feature points tracking method is proposed here, which is basedon the idea of competing trajectories similar to original three-frame
matching procedure. The basic difference is that multi-view constraint
is utilized besides the constraint of smooth motion, and the motion is
confirmed by a step of bidirectional validation. Every point in frames has
two state flags. The linking flag stands for correspondence of points inconsecutive frames of single camera, and the matching flag indicatescorrespondence of points from different cameras at the same time. Cost
function based on multi-view constraint and smoothness constraint isformed to obtain the best correspondence of points.

8558-14, Session 3

Baikhao (rice leaf) app: a mobile devicebased application in analyzing the color levelof the rice leaf for nitrogen estimation
Yuttana Intaravanne, Sarun Sumriddetchkajorn, National
Electronics and Computer Technology Ctr. (Thailand)
Nitrogen (N) is one of an important nutrient for the growth of rice crop.
As the color level of the rice leaf corresponds to the N status of rice inthe field, farmers use a cheap and ease-of-use leaf color chart (LCC)
to identify color level of the rice leaf for estimating the amount of N
fertilizers needed per rice field. However, the ability of the farmers anddegeneration of the LCC color affect the accuracy in reading the riceleaf color level. In this paper, we propose a mobile-device based riceleaf color analyzer called “Baikhao” which means rice leave in Thai. Our
key idea is to simultaneously capture and process the two-dimensional(2-D) data scattered from the rice leave and its surrounding reference,thus eliminating expensive external components and alleviating theenvironmental fluctuation but yet achieving a high accuracy of the
key color levels. Our field tests using an Android-based mobile phoneshow that all important leaf color levels of 1, 2, 3, 4, and 5 can becorrectly identified. Additional key features include low cost and ease of
implementation with highly efficient distribution through the internet.

8558-15, Session 3

In-line retro-reflective polarizing contrast
scope for translucent objects
Sarun Sumriddetchkajorn, National Electronics and Computer
Technology Ctr. (Thailand)
We propose a very-low-cost fixed interferential polarizing phase
contrast scope suitable for the study of translucent objects. Our key
design approach is relied on the arrangement of a circular polarizer
sheet, a mirror, and a digital camera in a retro-reflective opticalstructure. The linear polarizer embedded in the circular polarizer
sheet acts as both a polarization beam splitter and a polarization
beam combiner. Meanwhile the quarter waveplate inside the circularpolarizer sheet functions as a fixed phase plate but without narrowing
the field of view of the digital camera. The retro-reflective configuration
amplifies the phase difference between the two orthogonal polarized
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optical beams twice creating an initial dark background. Experimental
demonstration using an off-the-shelf digital microscope with builtin white light emitting diodes and a specified 400x maximum
magnification, a circular polarizer sheet, and a mirror shows thatonion cells and Steinernema Thailandense nematodes can be clearlyobserved with striking color, high contrast, and three-dimensional
appearance.

8558-16, Session 3

Design on imaging system base on FPGA
technology for EMBCCD
Liu Pan, Beijing Institute of Technology (China)
EMCCD (Electronic Multiplication CCD)is a new type of solid-state
imaging sensor.Owing to the unique feature of on-chip multiplication,
EMCCD obtains the same level of sensitivity compared with ICCD and
EBCCD, Back Illuminated EMCCD further enhanced the sensitivity.With
its special performance,EMCCD has various applications on astronomy,
aerospace, life science and military.In this article ,we design an imaging
system by chip CCD-97-00 ,which is produced by British E2V company.
Based on the datasheet of EMBCCD-CCD97, FPGA was utilized togenerate the timing sequence of EMBCCD, but the output voltage
of FPGA is 0 to 3.3v,in order to better meet the EMBCCD driving
specification, the exist driving circuit was substituted by a specialized
CMOS driver IC and a separate high voltage driving circuit for level
shifting;when we put the driver voltage to the pins of the EMBCCD,weobtain standard ccd sigal. The EMBCCD output analog signal was
sampled and converted to digital signal by a CCD signal processor
AD9845; The converted CCD digital sigal was transmitted to FPGA,
then cached in SDRAM and finally displayed on a VGA monitor.
Now the imaging system works well,the chip’s effective image size is
512*512 pixels.The fram rate is 7.5Hz, works smoothly and stabely.but
now it can’t used to observe at low illumination,but what we have done
now made an fundation for it.

8558-17, Session 3

A high-definition electronic industrial
endoscope based on embedded system
Guang Xu, Liqiang Wang, Zhejiang Univ. (China)
This paper presents a low power high-definition (HD) electronic
industrial endoscope based on embedded system. A 1/6 inch CMOS
image sensor is used to acquire HD images with 1280 *800 pixels.
The camera interface of A8 is designed to generate images of various
sizes and support multiple inputs of video such as ITU-R BT-601/656
standard. Image rotation (90 degrees clockwise) and image processfunctions can be achieved by CAMIF. The decode engine of theprocessor can playback or record HD video with speed of 30 frames
per second, built-in HDMI1.3 interface can transmit high definition
images to the external display. Image processing procedures such as
demosaicking, color correction and auto white balance are realized ona high performance cortex A8 platform. Diffirent functions are selected
through OSD settings. An LCD panel displays the real time images.
The snapshot pictures or compressed videos are saved in an SD cardor transmited to a computer through USB interface. The size of thecamera head is 5?5?15 mm with more than 3 meters working distance.
To acquire the clear image the brightness of led can be adjusted by theprocessor according to the environment, The whole endoscope system
can be powered by a lithium battery, with the advantages of miniature,
low cost and portability.

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8558-18, Session 38558-20, Session 4

A device designed and improved for
frequency decorrelation of speckle inmultimode fibers

VLC-based indoor location awareness using
LED lights and image sensors

Hongyuan Fu, Harbin Engineering Univ. (China)
Changes in environmental conditions can cause modal noise, but
frequency instability of the laser source can also cause such noise
under the right conditions. To avoid this case, the frequency changes
have to be less than the frequency decorrelation interval. The frequency
dependence of speckle is determined by the spread of time delays
associated with the various paths contributing to speckle at any given
point. The frequency change required to decorrelate a speckle patternat the end of a fiber is therefore approximately the reciprocal of thewidth of the impulse response of the fiber. In this paper, a device,for frequency decorrelation of speckle at the end of a fiber in thecomparison experiment, was designed and improved based on a theoryof time delays in propagation through multimode fiber. By control thefrequency of a diffuser drived by an external motor in the device, thefrequency decorrelation interval of speckle in fiber.can be control. The
experiment simulated the practical situation with the CCD to receive
star lights based on light from lab experiment and suppressed the
speckle pattern received from a large core fiber by different diffuserin speckle suppression devices. The experimental results, analysed
by MATLAB, showed that speckle contrast and the speckle spot in
the patterns treated by the device decreased obviously. This device
was demonstrated to be effective to speckle suppression and image
analysis in astronomy.

8558-19, Session 3

Extended depth-of-field for visual systems:
an overview
Yufu Qu, Liyan Liu, BeiHang Univ. (China)
The depth of field (DOF) determines the field of view along the opticalaxis in visual system. In this paper, we classify the existing extended
depth of field (EDOF) technology of visual system into the following
four types: (1) Simple improvement (Neither add optical elements nor
use image restoration). The DOF is extended by changing the elementsor parameters of the optical imaging system such as reducing theaperture of the imaging lens. However, the extension ratio of the DOF
of this method limited, and furthermore, the luminous flux and thesignal-to-noise ratio are reduced in the system. (2) Image restoration(Use image restoration only but not add optical elements). The DOF isextended by altering the parameters of the system to capture images
repeatedly. The large DOF is obtained with the aid of digital image
processing technology. The representative technology consists of focus
variation, aperture variation, defocus and DOF superposition, all ofwhich need multiple imaging and spend longer time (3) Element adding(Add optical elements only but not use image restoration). The DOF isextended by modifying the optical imaging system including optical
tomography microscope and digital holographic microscope, leading to
the complication of its structure. (4) Computational photography (Add
optical elements and use image restoration). By adding an elementin the system, the blurred images that are not sensitive to defocus iscaptured firstly. Then the image restoration is applied to render theblurred images sharp, resulting in DOF extension. Based on the locationof the additional elements, the computational photography is divided
into three types: light source, diaphragm and focal plane. Among them,
the type of diaphragm is composed of mask plate, phase plate, grid
focal lens and light field imaging. The mask plate contains gray, ring
multi-ring, modified uniformly redundant array (MURA), hole, Levin
and Veeraraghavan. Since the computational photography has anadvantage of simple implementation, large extension ratio of DOF, small
luminous flux loss and big signal-to-noise ratio, it becomes the leading
direction of the research and application in the future.

Seok-Ju Lee, Sung-Yoon Jung, Yeungnam Univ. (Korea,
Republic of)
Recently, indoor LED lighting can be considered for constructing green
infra with energy saving and additionally providing LED-IT convergence
services such as visible light communication (VLC) based location
awareness and navigation services. For example, in case of large
complex shopping mall, location awareness to navigate the destinationis very important issue. However, the conventional navigation using
GPS is not working indoors. Alternative location service based on
WLAN has a problem that the position accuracy is low. For example,
it is difficult to estimate the height exactly. If the position error of theheight is greater than the height between floors, it may cause big
problem. Therefore, conventional navigation is inappropriate for indoor
navigation. Alternative possible solution for indoor navigation is VLC
based location awareness scheme. Because indoor LED infra will bedefinitely equipped for providing lighting functionality, indoor LED
lighting has a possibility to provide relatively high accuracy of position
estimation combined with VLC technology. In this paper, we provide a
new VLC based positioning system using visible LED lights and image
sensors. Our system uses location of image sensor lens and locationof reception plane. By using more than two image sensor, we candetermine transmitter position less than 1m position error. Furthermore,
our positioning system also can be used in outdoor environment suchas intelligent transport system (ITS) thanks to its higher positioning
accuracy than GPS. Through numerical analysis, we verify the validityof the proposed VLC based new positioning system using visible LED
lights and image sensors.

8558-21, Session 4

Vision communications based on LED array
and imaging sensor
Jong-Ho Yoo, Sung-Yoon Jung, Yeungnam Univ. (Korea,
Republic of)In this paper, we propose the brand new communication concept,
called as “vision communications” based on LED array and image
sensor. This system consists of array LED as a transmitter and digital
devices which include image sensor such as CCD and CMOS as
receivers. In order to transmit data, the proposed communication
scheme simultaneously uses the digital image processing and opticalwireless communication schemes. Therefore, the novel cognitive
communications scheme is possible with the help of recognition
techniques used in vision system. By increasing data rate, our scheme
uses LED array consisting of several multi-spectral LEDs. Because each
LED can emit multi-spectral optical signal such as visible, infrared andultraviolet light, the increase of data rate is possible similar to WDM and
MIMO skills used in traditional optical and wireless communications.
In addition, this multi-spectral capability also makes it possible to
avoid the optical noises in communication environment. In our visioncommunication scheme, the data packet is composed of sync dataand information data. Sync data is used to detect the transmitter area
and calibrate the distorted image snapshots obtained by image sensor.
By making the optical rate of LED array be same with the frame rate
(frames per second) of image sensor, we can decode the information
data included in each image snapshot based on image processing andoptical wireless communication techniques. Through field test based onpractical test bed system, we confirm the validity of the proposed visioncommunications based on LED array and Image sensor.

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8558-22, Session 48558-24, Session 5

Designing and implementing a miniature
CMOS imaging system with USB interface

A fast mode decision algorithm for multiview
auto-stereoscopic 3D video coding based onmode and disparity statistic analysis

Chenyun Yao, Liqiang Wang, Bo Yuan, Zhejiang Univ. (China)
Although CMOS cameras with USB interface are popular, their sizes are
not small enough and working lengths are not that long enough whenused as industrial endoscope. Here we present a small-sized image
acquisition system for high-definition industrial electronic endoscope
based on USB2.0 controller CY7C68013, which is composed of a
1/6 inch CMOS image sensor with resolution of 1 Megapixels. Usingslave FIFO mode , signals from the CMOS image sensor are put into
computer through the USB interface for processing, storage anddisplay. LVDS technology is used for image data stream transmission
between the sensor and USB controller to realize a long working
distance, high signal integrity and low noise system. The maximum
pixel clock runs at 48MHz to support for 30 fps for QSXGA mode or
15 fps for SXGA mode and the data transmission rate can reach 36
megabytes per second. The imaging system is simple in structure, lowpower, low-cost and easy to control. Based on multi-thread technology,
the software system which realizes the function of automatic whitebalance, brightness, hue and saturation adjustment with the method of
establishing the corresponding relationship between YUV data and RGB
data is also designed.

8558-23, Session 4

Design and implementation of non-linear
image processing functions for CMOS image
sensorPurnawarman Musa, Univ. de Bourgogne (France) andUniv. Gunadarma (Indonesia); Sunny A. Sudiro, Institute ofInformatics Management and Computer Jakarta (STI&K)(Indonesia); Eri P. Wibowo, Suryadi Harmanto, Univ. Gunadarma(Indonesia); Michel Paindavoine, Univ. de Bourgogne (France)
Today, solid state image sensors are used many applications likein mobile phones, video surveillance systems, embedded medical
imaging and industrial vision systems. These image sensors require
the integration in the focal plane (or near the focal plane) of complex
image processing algorithms. Such devices must meet the constraints
related to the quality of acquired images, speed and performance ofembedded processing, as well as low power consumption. To achievethese objectives, low-level analog processing allows extracting theuseful information in the scene directly. For example, edge detection
step followed with a local maxima extraction will facilitate the highlevel processing like objects pattern recognition in a visual scene. Our
goal was to design an intelligent image sensor prototype achieving
high-speed image acquisition and non-linear image processing (likelocal minima and maxima calculations). For this purpose, we present
in this article the design and test of a 64x64 pixels image sensor built
in a standard CMOS Technology 0.35?m and including non-linear
image processing. The architecture of our sensor, named nLiRIC (nonLinear Rapid Image Capture), is based on the implementation of ananalog Minima/Maxima Unit. This MMU calculates the minimum andmaximum values (non-linear functions), in real time, in a 2x2 pixels
neighbourhood. Each MMU needs 42 transistors and the pitch of one
pixel is 40?m. The total area of the 64x64 pixels is 11mm?. Our tests
have shown the validity of the main functions of our new image sensor
like fast image acquisition (1K frames per second), minima/maxima
calculations in less then one ms.

Cong Ding, Xinzhu Sang, Tianqi Zhao, Binbin Yan, Junmin
Leng, Jinhui Yuan, Ying Zhang, Beijing Univ. of Posts andTelecommunications (China)
Abstract--Multiview video coding (MVC) is essential for applicationsof the auto-stereoscopic three-dimensional displays. Because
MVC inherently contains more visual data and adopts exhaustive
variable size mode decision, multiple reference frame selection isused to significantly improve high compression efficiency at eachmacroblock(MB). However, the computational complexity of MVC
encoders is tremendously increased. Fast algorithms are very desirable
for the practical applications of MVC. Based on joint early termination,
the selection of inter-view prediction and the optimization of theprocess of Inter8x8 modes by comparison, a fast macroblock mode
selection algorithm is presented. Firstly, each macroblock is checked
whether the rate-distortion(RD) cost of Skip mode is below a predefined‘low’ threshold or above the ‘high’ threshold, to make an earlytermination or narrow the candidate modes. If neither, Inter16x16 mode
will be checked. Then, by utilizing Inter16x16 mode prediction results,
the disparity estimation of other Inter modes is guided to bypass theun-necessary inter-view prediction. Finally, by compareing the cost ofInter16x16 with Inter8x8 mode, we can predict the more likely situationof actual motion. Thus, the unlikely candidate modes will be excluded
further. As compared to the full mode decision in MVC, the experimentresults show that the proposed algorithm can reduce up to 78.13% on
average and maximum 90.21% encoding time with a little increase in bit
rates and loss in PSNR.

8558-25, Session 5

Stereo correspondence of contour using
dynamic programming
Junqin Lin, Dayuan Yan, Xiaoming Hu, Qiaona Xing, Bo Yang,
Beijing Institute of Technology (China)
Stereo correspondence is one of the most active research areas instereo vision. In order to solve the problem of large similar gray-scaleregion areas and the time-consuming in the dense reconstruction, anovel correspondence algorithm, in which the contour of stereo pairs
is extracted to reconstruct the scene, is discussed in this paper. Cannyalgorithm is selected to extract the contour for it can get a complete,continuous and single-pixel outlines, which is superior to the traditionaledge detection algorithms such as Sobel operator, Laplace operator
and so on.
A noisy disparity map might be produced if the disparity is solved byusing traditional matching algorithms (such as SAD, census, etc.) whichchoose the optimal disparity for each pixel individual. To reduce thenoise which will influence the accuracy rate of stereo matching, a stereo
matching algorithm applying on the contour based on the dynamic
programming is proposed in the paper. Based on the reasonable andcommonly assumption that the disparity of the scene is always smooth,each disparity is constrained to with the values of its neighbors’
disparities, in which its neighbors mean the adjacent pixels along thesame contour of the image. The searching scale could be reduced aswell. As the Dynamic Programming algorithm is applied on the contours
with the disparity constrain, the optimal disparity which has theminimum cost along the contour will be obtained.
Since the sum of points that need to be computed are greatly
reduced by the edge detection and the disparity is optimal by the
Dynamic Programming, the algorithm has a faster speed than dense
reconstruction and a higher matching-rate.

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8558-27, Session 58558-26, Poster Session

Generation of fractal Chinese characters
based on IFS

Target contour extraction for shipborne
active range-gated imaging

Zhengbing Zhang, Wei Zhang, Yangtze Univ. (China)

Chao Liu, Xinwei Wang, Yan Zhou, Yuliang Liu, Institute of
Semiconductors (China)

The theory of iterated function systems (IFS) has been used ingenerating fractal graphics. In this paper, a method is proposed togenerate fractal Chinese characters with IFS. Each Chinese character
generated with this method is actually the attractor of an IFS, therefore
it has the property of self-similarity. A Chinese character is usuallycomposed of a number of strokes. In most cases, one stroke can bemodeled with only one affirn mapping, but in some special cases, one
stroke is divided into two or more parts and modeled with two or more
mappings in order to make every mapping be contractive. The finite
set of the contractive affirn mappings that model all the strokes of
the whole character construct the IFS for that Chinese character. It is
important to determine the affirn mapping coefficients for each stroke.
The symbol X is used to denote the square area with its upper-leftcorner at (0, 0) and lower-right corner at (1, 1), while the symbol C isused to denote the Chinese character to be modeled with an IFS, wn(n = 1, 2, ..., N) to denote the affirn mappings that model C, and Sn(n = 1, 2, ..., N) to denote the strokes or stoke parts corresponding to
wn. Suppose C is included in X, then wn maps X into Sn. For eachaffirn mapping, there are 6 coefficients, which are calculated by solving
matrix equation with three pairs of corner points in X and Sn. Formulas
to find out the coefficients of wn are deduced in this paper. After thecoefficients of all the affirn mappings for a Chinese character havebeen determined, the random iteration algorithm is used to show thecorresponding fractal Chinese character. The experimental results
show that the generated fractal Chinese characters are self-similar andbeautiful.

8558-28, Session 5

New algorithms based on data
reorganization for three-dimensional point
cloud data partition
Meinan Li, Qun Hao, Yong Song, Beijing Institute of Technology(China)With the development of 3-D imaging techniques, three dimensional
point cloud partition becomes one of the key research fields. In thispaper, two data partition algorithms are proposed. Each algorithm
includes two parts: data re-organization and data classification. Two
methods for data re-organization are proposed: dimension reduction
and triangle mesh reconstruction.
The distribution of 3-D point cloud is massy and disordered in thespace. Dimension reduction investigates the x and y boundary of thedata, divides the data into x-y cubes, then the depth data is stored in
2-D matrix like gray image. Triangle mesh reconstruction describes thedata in 3-D grid. The triangulation algorithm is based on dominatingedge of point cloud data.
Following the dimension reduction, the algorithm of data classification
is based on edge detection of depth data. The edge detection
algorithms of gray images are improved for depth data partition. As
to the triangulation method, the data partition is realized by region
growing, starting from several points, judging the depth-related propertyof the all the points through the triangle grid.
The simulation result shows that the two methods can achieve point
cloud data partition of standard template and real scene. The result ofstandard template shows the total error rates of the two algorithms areboth less than 3%.

A shipborne ranged-gated night vision system which can achieve target
finding, target tracing and ranging improves the ability of navigation,
positioning and obstacle avoidance for nocturnal operated ships.
However, shortcomings such as the vague edges of ranged-gatedimages and complex backgrounds outside the target impede theaccuracy of ranging and the exact target tracing. Therefore, target(ships) acquisition is of great importance for shipborne night visionsystem to avoid the interference of waves, islands and buoys. A digital
image processing algorithm is developed for the mentioned night visionequipment above. After image preprocessing like denoising, target
contour is extracted using Canny edge detection algorithm based on
self-adapted Otsu threshold segmentation. Furthermore, on accountof the vague edges especially for range-gated images, edge thinning,edge connection and morphologic methods are implemented toameliorate the acquired contour. The entire pixels of the ROI( region ofinterest) are needed for ranging, hence, pixels inside the contour arecollected utilizing horizontal-vertical traverse and Zigzag traverse. After
single and multiple targets (mainly ships) from range-gated imaging
equipment being all tested, target contour and inner pixels can both beacquired through this algorithm.

8558-34, Poster Session

An effective method of eliminating ghostingin image mosaic
Shurui Zhao, Univ. of Electronic Science and Technology ofChina (China)
Image mosaic is useful for a variety of tasks in both vision andcomputer graphics. Image fusion method directly affects the stitchingeffect. If there are moving objects in the images, the same object
may add together after fusion and cause ghosting. A fusion method
which can effectively eliminate the exposure difference and ghosting isessential to image mosaic.
The method of optimal seam can eliminate integrated ghosting. But the
optimal seam may include individual error points and its overall strength
is the smallest. The line is incorrectly taken as the optimal seam. So theghosting may still exist.
In order to avoid the impact of error points an improved optimal seambased on feature point is proposed in this paper. The scale invariant
feature transform (SIFT) and the random sample consensus (RANSAC)
are used to ensure the detected feature points are accurate. The
improved optimal seam is different from the original optimal seam
regards the point has the smallest guidelines value as extended
direction this paper regards the feature point as the extended direction.
The feature point’s strength value should have an appropriate weightvalue. In this way it can avoid the error points and dynamic elements.
Both sides of the optimal seam have exposure differences, an image
fusion method should be taken to achieve smooth and natural mosaic.
Poisson fusion method can achieve the synthesis of the fragment,
thereby maintaining a continuous transition between the two different
fragments. So Poisson fusion is used to eliminate exposure differencein this paper. Experimental results show that the proposed method caneffectively eliminate the ghosting and achieve seamless mosaic.

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8558-36, Poster Session

8558-45, Poster Session

Calculating method for the brightness of
spatial objects in engineering

LDPC codes in wireless opticalcommunication application

Tang Jia, Gao Xin, Beijing Institute of Tracking and
Telecommunication Technology (China)

Xiangxiang Chang, Univ. of Electronic Science and Technology
of China (China)

Calculating the ground illumination of the space objects is thenecessary way to calculate the objects brightness from reflecting
sunlight. The ground illumination of the space objects are dependent
on the sunlight direction and observation direction, that is in direct
proportion to the integral of cosq1?cosq2. q1 is the angle between
the target surface element normal and the sunlight incident direction.
q2 is the angle between the target surface element normal and theobservation direction.

We introduced and analyzed the basic principles of LDPC codes andthe techniques of coding and decoding in detail. Also we applied
the LDPC code in the wireless optical communication system, built
the model of the system, simulated and analyzed the application,and proved the improvement of the performance of wireless opticalcommunication finally. In the case of weak turbulence, the coding
gain of LDPC with 5 iterations is 3 dB higher than uncoded system’s
when the bit error rate is . In the case of strong turbulence, the bit error
rate of system with 5 iterations LDPC is 2 orders of magnitude lower
than uncoded one. And with the number of iterations increased, theimprovement of the system will become more apparent.

The integral of cosq1?cosq2 is different to difform object. Integral
complexity increases with the increase in the complexity of the surface
shape. This paper introduces a simple way through vector integral tocalculate of cosq1?cosq2. cosq1 is represented by the sunlight incident
direction vector and the target surface element normal direction vector.
cosq2 is represented by the observation direction vector and thetarget surface element normal direction vector. In this way, the integral
expressions is changed from angle cosine integral into the integral forthe direction vector ,that simplifies the complexity of the integral largely.
As an example, the object is used to illustrate the process of vector
integral method. The results in this way are same as that indicated inliterature. The characteristic of vector integral method is processing in
the right-angle coordinate so that doesn’t be limited by geometric formof the space objects. The rule of selecting a system of coordinates isease to calculate. According the selected system of coordinates andthe right-angle integral surface (xoy, xoz or yoz), the expression of
integral is different .

8558-44, Poster Session

Research on system modeling anddata reconstruction for spatial coding
compressive spectral imaging
Yuheng Chen, Xinhua Chen, Yiqun Ji, Jiankang Zhou, Weimin
Shen, Soochow Univ. (China)
Compressive spectral imaging is a kind of novel spectral imaging
technique that combines traditional spectral imaging method with newconcept of compressive sensing. Spatial coding compressive spectral
imaging realizes snapshot imaging and the data cube dimension
reduction by successive modulation, dispersion and aliasing of the lightsignal. It reduces acquisition data amount, increases imaging signalto-noise ratio, realizes snapshot imaging for large field of view and has
already been applied in the occasions such as high-speed imaging,fluorescent imaging and so on. In this paper, the physical model forsingle dispersion spatial coding compressive spectral imaging is built
on which the data flow procession is analyzed and its reconstruction
issue is concluded. The existing sparse reconstruction methods areinvestigated and the specific module based on the two-step iterative
shrinkage/thresholding algorithm is built so as to execute the imaging
data reconstruction. A regularizer based on the total-variation form is
included in the unconstrained minimization problem so that the smooth
extent of the spectral data cube can be controlled by altering its tuning
parameter. To verify the system modeling and data reconstruction
method, a simulation imaging experiment is carried out, for which a
specific imaging scenery of both spatial and spectral features is firstly
built. The mean square errors of the whole-band reconstructed spectral
images under different regularization tuning parameters are calculated
so that the relation between imaging quality and the tuning parameter isrevealed, which contributes to corresponding parameter optimization.

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8558-46, Poster Session

A real-time TV logo tracking method using
template matching
Zhi Li, Xinzhu Sang, Binbin Yan, Beijing Univ. of Posts andTelecommunications (China); Junmin Leng, Beijing Information
Science & Technology Univ. (China)
This paper presents a fast and accurate TV Logo detection algorithm
aiming at both semi-opaque and opaque logos. The algorithm can bedivided into two individual steps. Firstly extract logo templates fromseveral video streams containing target TV Logos. A revised effective
time averaging method is proposed to attain preprocessed logo
images. The background can be erased entirely if sufficient frames
are processed. Then noise eliminating and smoothing is processed onthese logo images using median and mean filter separately. The edge
detection on them results in logo templates. Secondly track logos in realtime video streams. A tracking window is used for searching the logos.
The cross correlation coefficient is calculated as the matching criterion
by moving logo templates within the window. The maximum coefficientis chose to compare with a predefined threshold. If it is beyond thethreshold, the logo is judged that it appears in the frame and vice versa.
Our algorithms are carried out and tested. 12 video streams from 12
broadcasting station are selected, including 7 semi-transparent logos(CCTV1, CCTV2, CCTV7, CCTV10, CCTV11, CCTV12, CCTV-music)
and 5 opaque logos (HNTV, HBTV, BTV, TJTV, NMGTV). The resolution
definition of the video stream is 768?576. Each stream lasts 30 minutes.
The templates are extracted using the corresponding video file recorded
from the broadcast stream. The matching accuracy can be up to 99%.
The time to process a frame is less than 15ms. The frame rate of video
stream is 30fps, namely the time interval between two frames is 30ms.
It is fast and accurate enough for the real time application.

8558-47, Poster Session

Imaging reconstruction based on improved
wavelet denoising combined with parallelbeam filtered back-projection algorithm
Zhong Ren, Guodong Liu, Zhen Huang, Jiangxi Science andTechnology Normal University (China)
The image reconstruction is a key step in medical imaging(MI) and its
algorithm’s performance determinates the quality and resolution ofreconstructed image. Although some algorithms have been used, filter
back-projection (FBP) algorithm is still the classical and commonly-usedalgorithm in clinical MI. In FBP algorithm, filtering of original projection
data is a key step in order to overcome artifact of the reconstructed
image. Since simple using of classical filters, such as Shepp-

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Logan(SL), Ram-Lak(RL) filter have some drawbacks and limitationsin practical situation, especially for the projection data polluted by
non-stationary random noises. So, an improved wavelet denoisingcombined with parallel-beam FBP algorithm is used to enhance thequality of reconstructed image in this paper. In the experiments, thereconstructed effects were compared between the improved wavelet
denoising and classical Donoho’s threshold denosing functions andothers (directly FBP, mean filter combined FBP and median filter
combined FBP method). To determine the optimum reconstruction
effect, different wavelet decomposition scales, different wavelet bases
combined with three filters were respectively test. Experimental results
show the reconstruction effect of improved FBP algorithm is better thanthat of others. Comparing the results of different algorithms based on
two evaluation standards (i.e. mean-square error (MSE), peak-to-peaksignal-noise ratio (PSNR)), it was found that the reconstructed effects of
the improved FBP based on db2 and RL filter at decomposition scale 2
was best, its MSE value was less and the PSNR value was higher thanothers. Therefore, this improved FBP algorithm has potential value inthe medical imaging.

appearance of texture. But it only encodes the gray-level informationand lack of enough texture features to encode the wrinkles.
To overcome the drawbacks of AAM, a novel age estimation method
using AAM combining with local texture features is presented. The
multi-scale local binary pattern (MLBP) is served as the local texture
descriptor to get the rotation invariant texture features. Build thestatistic shape model, and sample the MLBP features instead ofgray-level information to build the new texture model, and thenapply PCA analysis to combine the shape and MLBP texture model
to finish building the combined AAM model. In this way, both global
face features and local texture features are used to provide enoughaging information. The support vector regression (SVR) is used toestimate the facial age. The face aging data set FG-NET is used, whichcontains 1002 face images of 82 people with age ranging 0-69 years.
Experimental results demonstrate the AAM combined MLBP method
performing a lower mean-absolute error (MAE) and high accuracy of
estimation comparing to other method results.

8558-50, Poster Session
8558-48, Poster Session

Study on thickness measurement of multialkali photocathodeXiaofeng Li, Qiang Lu, North Night Vision Technology Co., Ltd.
(China)In this paper the optical properties and spectral reflectancecharacteristics of multi alkali photocathode were illustrated andspectral reflectance curve of multi alkali photocathode were measured.
The shape of spectral reflectance curve is irregular compared withordinary optical film. The reason is that the cathode layer absorbs light.
Interference peak of spectral reflectance curve is the results that thereflection light on the interface between the glass and the cathodelayer and the reflection light on the interface between the cathode layer
and vacuum interference together. According to interference theory,
if two beam light reflected by the cathode film have the optical path
difference of even times the l/2, interference enhancement peak on
spectral reflection cure will appear. Similarly, if two beam light reflectedby the cathode film have the optical path difference of odd times
the l/2, interference decreased peak on spectral reflection cure willappear. According to the interference theory and peak wavelength on
spectral reflection interference curve the cathode film thickness of thesuper second generation image intensifier can be calculated out. The
thickness is about 191nm, and increased by 38% compared with thesecond generation image intensifier. Determination of thickness simply
by observing cathode film color was not an accurate method. Practicehas proved that, the method to calculate the cathode film thickness byusing spectral reflectance method is simple and effective. If the spectralreflectance were monitored during the process of cathode production,then the thickness of cathode layer would be able to control precisely,
and the cathode study would be more in-depth, cathode sensitivity
would be further improved.

8558-49, Poster Session

Age estimation using active appearance
model combine with local texture features
Chunhua Xie, Zhenming Peng, Univ. of Electronic Science andTechnology of China (China)
Image based age estimation is a new challenging research topic incomputer vision field. Large efforts have been devoted by researchers inrecent years. However finding an appropriate age feature representation
remains an open problem.
In this paper, we focus on the age feature representation method. The
active appearance model (AAM) is widely used to build the age features.
The original AAM contains a statistic model of shape and a gray level

Target tracking using multiple templates
based on maximum pixel count criterion
Jie Pu, Zhenming Peng, Univ. of Electronic Science andTechnology of China (China)
Image matching plays an important role for target tracking in image
processing filed. It has been widely used in image fusion, target
detection, target positioning and image reconstruction, etc. There
are many correlation or distance criterions for image matching, suchas mean absolute difference (MAD), mean square difference (MSD)
and normalized cross correlation (NCC) algorithm, but the existingalgorithms usually have high computationally expensive and affectedeasily by noises and distortion in images. A method of target tracking
using multiple templates based on maximum pixel count (MPC) criterion
is presented in this paper.
The key issue of MPC criterion is counting the number of similar points.
However, we can’t make sure which the best matching image is when
there is two or more sub-image having the same number of similar
points. So a new template matching algorithm which considers not
only the number of similar points but the error is proposed. While thesub-images have the same number of similar points, it would choose
the best matching sub-image by calculating the summation of the error.
Meanwhile, the original template is divided into five small templates topatch the problem that single template is affected easily by geometricdistortion. Because the small divided template has fewer pixels thanthe original template, geometric distortion just affects the relevant small
template and the final result will be obtained by comprehensive use of
the other templates without the effect of distortion. The experimental
results show that the proposed algorithm which combines the improved
MPC criterion with the multiple divided templates is accurate, effective
and feasible for target tracking.

8558-51, Poster Session

Compound algorithm for restoration ofheavy turbulence-degraded image for spacetargetLiang-liang Wang, Ru-jie Wang, Ming Li, Beijing Institute ofTracking and Telecommunication Technology (China); Zi-qianKang, Heibei Communication Design & Consultation Co. Ltd(China); Xiao-qin Xu, Xin Gao, Beijing Institute of Tracking and
Telecommunication Technology (China)
Restoration of atmospheric turbulence degraded image is needed
to be solved as soon as possible in the field of astronomical spacetechnology. Owing to the fact that the point spread function of
turbulence is unknown, changeable with time, hard to be described

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Conference 8558:
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by mathematics models, withal, kinds of noises would be brought
during the imaging processes (such as sensor noise), the image forspace target is edge blurred and heavy noised, which making a single
restoration algorithm to reach the requirement of restoration difficult.
Focusing the fact that the image for space target which was fetchedduring observation by ground-based optical telescopes is heavy
noisy turbulence degraded, this paper discusses the adjustment andreformation of various algorithm structures as well as the selectionof various parameters, after the combination of the nonlinear
filter algorithm based on noise spatial characteristics, restoration
algorithm of heavy turbulence degrade image for space target basedon regularization, and the statistics theory based EM restoration
algorithms. The intelligent combination of various algorithm structures
is accomplished to achieve their superiority. In order to test the validityof the algorithm, a series of restoration experiments are performedon the heavy noisy turbulence-degraded images for space target.
The experiment results show that the proposed compound algorithm
can achieve detail preservation simultaneously, which is effective andpractical.

different altitudes even has a difference of a thousand of times. Thus,
when the light intensity, shape and location of sun in the image keepchanging, it is critical for obtaining and following the position of thestrongest sunlight accurately.
In the paper, a novel method of sun scene simulation for observationof the sun through the atmosphere is presented. The method basedon the active optical control system, is used in sun scene simulation
with the variation of light intensity, shape and position. The continuous
variation of light intensity, shape and position of sun can be calculatedwith computer, and the computer can also be used to output solar
brightness of simulation to the industrial projector and to control
micro-deformable mirror with 109 channels, for simulating the shapeand position of sun. The method has a simple theory and is easy to berealized. Industrial projector can output solar brightness accurately withthe difference of a thousand of times, and Micro- deformable mirror
has the correct and rapid response to control signals for ensuring theaccuracy and real-time sun scene simulation.

8558-54, Poster Session
8558-52, Poster Session

Depth field problem in electronic image
stabilization
Chen Huang, Beijing Institute of Tracking and
Telecommunications Technology (China)
For electronic image stabilization EIS process of the image sequence,
the target scene in different depth of image field have different motion
vectors to the dithering caused by imaging system moving. There is
not a compensation amount can stable both close-range and longrange target scene, namely the depth of field problem in electronic
image stabilization. The past electronic image stabilization algorithm
by solving the global motion vector filtering and compensation, andthis could not effectively solve the depth of field problem. This article
analysis of the depth of field problem by the optical imaging model,
use the Harris corner detector algorithm to detect the target scenefeature points and feature matching, calculation of the different depthof field motion vector of target scene. Proposed a motion vector
compensation method based on electronic image stabilization image
quality assessment. Compensate the image after assign value fordifferent depth of field motion vector of target scene, according toassess the image inter-frame differential map and peak signal-to-noise
ratio of these two indicators. To adjust the distribution of motion vector
assign values based on the results of the assessment feedback. For theassessment of electronic image stabilization image quality is a visual
optimization process, we take a local optimal solution to optimize thevalue to assign. Experimental results show that for the target scene indifferent depth of image field the motion vector compensation effectin the optimization of the value is better than the global motion vector
compensation.

8558-53, Poster Session

Method of Sun scene simulation basedon active optical control system for solar
occultation measurement
Fei Yu, Zhe Lin, Xiao-jun Kang, Beijing Institute of Space
Mechanics and Electricity (China); Ling-Qin Kong, Yuejin Zhao,
Beijing Institute of Technology (China)
During the detection of the atmosphere material, sun is used as lightsource for spectrum analysis of light through atmosphere with detectors
on the satellite. However, due to the inhomogeneity of the atmospherein the air, the shape of sun through the atmosphere of different heights
is very different. In the process of changing height in the atmosphere,
the gray image of sun is not only an irregular circle, and even is divided
into different parts, and the intensity of sunlight through clouds at

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Digital image information hiding based oncompressive sensing and double randomphase encoding technique
Lu Pei, Institute of Optics and Electronics (China) and Shihezi
Univ. (China) and Graduate Univ. of Chinese Academyof Sciences (China); Zhiyong Xu, Institute of Optics andElectronics (China); Xi Lu, 34th China Electronics Technology
Group Co. (China); Xiaoyong Liu, Sichuan Univ. (China)
With the increase of the importance of information security, theinformation hiding system based on optical encryption is widely usedbecause of the possibility of high speed parallel encryption of 2-D
image data. A typical image information hiding method with advantagesof optical implementation and high robustness is based on double
random-phase encoding technique. For an intercepted image, however,analyzing the probability of hidden information is feasible by a statisticaldetection method. In this paper, an image information hiding scheme
based on Compressive Sensing and double random-phase encoding
is proposed which is meaningful due to the high computational
complexity of cracking. Firstly, we utilize the characteristics ofCompressive Sensing, dimensional reduction and random projection,
to sample a digital image, where the obtained measured values withlow data volume passed through measurement matrix are considered
important or unimportant equivalently and loss of a few can still
perfectly reconstruct the original signal. Then, the measured values
are re-encrypted by double random-phase encoding technique withsmaller random phase masks. In order to increase the system security
and make the keys easy to custody, the measurement matrix andthe random phase masks are generated by the sequence of irrational
number. At the received terminal, the original image information isreconstructed approximately by Orthogonal Matching Pursuit algorithm.
Numerical experiments show that this method has following features:
low data volume for hiding and high information security.

8558-55, Poster Session

Image process technique used in a large
FOV compound eye imaging system
Axiu Cao, Sichuan Univ. (China) and Institute of Optics
and Electronics (China); Lifang Shi, Institute of Optics andElectronics (China); Ruiying Shi, Sichuan Univ. (China); Qiling
Deng, Institute of Optics and Electronics (China); Chunlei Du,
Chongqing Institute of Green and Intelligent Technology (China)
Because of the unique optical scheme for imaging and a huge potential
for medical, industrial and military applications, compound eyes withwide field of view (FOV) have attracted a great deal of research interest.

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In recent years, many research groups have developed studies about
artificial compound eyes, but the researches only focus on the design
and fabrication. For practical implementation of compound eyes withwide FOV, the requirement of image process techniques based on
multiple optical channels is evident. In this paper, an imaging system
contained 19 lenses based on compound eyes with FOV of 112 degrees
has been designed, and the study of the image process techniques has
been presented.
By analyzing the FOV relationship between the system and each lens,
the arrangement of the lenses can be designed. By researching therelationship between the lens position and the corresponding image
geometrical shape to realize large FOV detection, an image process
technique is proposed. The sub-image captured by each lens is
processed and projected onto a spherical surface. All the sub-images
on the spherical surface can be assembled to form a large FOV image.
The process and projection methods are studied in the manuscript. By
researching the relationship between the image spherical and traditional
plane display, the spherical image is extended onto a plane for better
visual effect. Corresponding image optimization methods are studied toobtain better image quality. To verify the above methods, experiments
are carried out based on the designed compound eye imaging system.
The results show that an image with FOV over 112 degrees can beacquired while keeping excellent image process quality.

8558-56, Poster Session

An artificial compound eye system for large
field imaging
Yan Liu, Sichuan Univ. (China) and Institute of Optics andElectronics (China); Lifang Shi, Institute of Optics andElectronics (China); Ruiying Shi, Sichuan Univ. (China);
Xiaochun Dong, Qiling Deng, Institute of Optics and Electronics(China); Chunlei Du, Chongqing Institute of Green and Intelligent
Technology (China)
With the rapid development of science and technology, optical imaging
system has been widely used, and the performance requirements are
getting higher and higher such as lighter weight, smaller size, larger fieldof view and more sensitive to the moving targets. With the advantagesof large field of view, high agility, and muti-channels, compound eye ismore and more concerned by academia and industry. In this work, an
artificial spherical compound eye imaging system is proposed, which isformed by several mini cameras to get a large field of view. By analyzing
the relationship of the view field between every single camera andthe whole system, the geometric arrangement of cameras is studied
and the compound eye structure is designed. By using the precision
machining technology, the system can be manufactured. To verify theperformance of this system, experiments were carried out, where thecompound eye was formed by seven mini cameras which were placed
centripetally along a spherical surface so that each camera points in adifferent direction. Pictures taken by these cameras were mosaiced into
a complete image with wide field of view. The results of the experiments
prove the validity of the design method and the fabrication technology.
By increasing the number of the cameras, larger view field evenpanoramic imaging can be realized by using this artificial compoundeye.

method of target detection can be divided into offline machine learningand online features cumulating. But the first method needs a priori
model of the specific target through extracting the unique features oftrainings, which is difficult to meet the requirements of the complex
scenes. So this paper focused on the online features cumulating.
In this paper, a novel motion target detection method based on the
Fourier descriptors of the fractal edge is presented. Because the carpet
fractal algorithm has good anti-noise performance, and be able to geta continuous edge with the high scale, so it’s very applicable to detect
the artificial targets. Then get binarization of the features with the
maximum entropy threshold segmentation, through labeling targets andremoving small area noise targets, the result contains stationary andmoving artificial targets. In order to distinguish them, the elliptic Fourier
descriptors are used to describe the binary shape features of theartificial targets between multi-frames, establish the links of multi-frame
target Fourier descriptors and count the frequencies of descriptors,
the frequencies can decide which one is the moving target and which
is not. Experiment found that only use the edge information of thehigh scales, and eliminate the Logarithm, which greatly reduce thecomputational. Compared to other feature detection and accumulation
algorithms, this proposed algorithm is much simpler and well suited forcomplex environment.

8558-58, Poster Session

Improving videometric precision withadaptive optics based on stochastic parallel
gradient descent algorithm
Junfeng Cui, Sanhong Wang, Taiyuan Satellite Launch Ctr.
(China); Guangwen Jiang, Haotong Ma, National Univ. of
Defense Technology (China)
In a videometric system, there are many factors can induce thedynamic optic aberrations such as vibration, temperature variation andatmospheric turbulence. Because the dynamic aberrations can’t becalibrated and amended, they will degrade the videometric system’s
precision. However, adaptive optics (AO) technique has been widelyused to correct for wavefront distortions in astronomy, vision scienceand laser. So adaptive optics technique is proposed to correct forthe optic aberrations (include dynamic and static) in the videometricsystem. Since there are simple structure and low cost, the adaptive
optics system based on stochastic parallel gradient (SPGD) algorithm
will be used to improve the videometric precision. In such an adaptive
optics system, a deformable mirror is controlled by the SPGD
algorithm to optimize a scalar beam quality metric. According to thealgorithm, statistically independent small random perturbations are
simultaneously applied to all the control channels of the deformablemirror in each iteration step, and the stochastic approximation of
the corresponding gradient component of the beam quality metric is
subsequently measured. So the convergence speed of this algorithm
is faster than that of the conventional gradient descent algorithm. A
videometric system with adaptive optics based on SPGD algorithm wasmodeled numerically in this paper. Then, videometric experiments withaberrations and with aberrations been corrected for by adaptive optics
based on SPGD algorithm were numerically conducted to compare
the measurement accuracies of the two cases. The results show thatthe adaptive optics system can effectively improve the videometricsystem’s precision.

8558-57, Poster Session

Motion target detection based on the Fourier
descriptors of the fractal edge in complex
environment
Jing Liang, Zhenming Peng, Univ. of Electronic Science andTechnology of China (China)
Detection of moving targets in moving background is a difficult problem
in the field of computer vision, throughout the past few years the8558-59, Poster Session

The control technique of delay-time jitterfrom the echo-transponder satellite laser
ranging
Jian-ting Li, Beijing Institute of Tracking and Telecommunication
Technology (China)

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Because of the familiar R2 dependence of signal strength on range,and overcoming the prohibitively large R4 losses like the conventionalreflecting satellite laser ranging (SLR), the operational distance of theecho-transponder satellite laser ranging is much farther. The echotransponder SLR can be used for satellite ranging at the great distance,and even for the deep-space probe ranging. The echo-transponder SLR
uses the laser transponder instead of the retro-reflector on satellite,
and implements the ranging by means of echoing the ranging signal
from the master station. However, the ranging precision of the echotransponder SLR is reduced, because the jitter of the additional delaytime occurs in the process of the transponder’s response. The principleof laser echo transponder was introduced, the causes of delay-time andits jitter were analyzed, and the control technique of delay-time jitterin the responsion was studied. An experimental platform of the laser
echo responder was fabricated, in order to validate the availability of thecontrol technique of delay-time jitter, and to detect the control accuracyof the delay-time jitter. As the experimental result indicated, the delaytime jitter of the laser echo transponder could be controlled effectively
within 1 ns, thereby it was determined that the corresponding ranging
precision was less than 15 cm, if the laser transmitter was suitably
selected, and the techniques about the precise temperature control,
the power automatic control, the precise Q-switched, and the accurate
detection of pulse time were reasonably put to use in the system designof the laser echo transponder.

8558-60, Poster Session

Robust object recognition based on HMAX
model architecture
Yongxin Chang, Institute of Optics and Electronics (China) andUniv. of Electronic Science and Technology of China (China);
Zhiyong Xu, Chengyu Fu, Institute of Optics and Electronics(China); Chunming Gao, Univ of Electronic Science andTechnology of China (China)
In this paper, we describe in detail the hierarchical model and X (HMAX)
model of Riesenhuber and Poggio. The HMAX model, accounting
for visual processing and making plausible predictions founded onprior information, is built up by alternating simple cell layers andcomplex cell layers. We generalize the principal facts about the ventral
visual stream and argue hierarchy of brain areas to mediate object
recognition in visual cortex. Then, in order to obtain the futures ofobject, we implement Gabor filters and alternately apply templatematching and maximum operations for input image. Finally, according
to the target feature saliency and position information, we introduce
a novel algorithm for object recognition in clutter based on the
HMAX architecture. The improved model is competitive with current
recognizing algorithms on standard database, such as the UICI car
and the Caltech101 database including a large number of diverse
categories. We also prove that the approach combining spatial position
information of parts with the feature fusing can further promotes
the recognition rate. The experimental results demonstrate that the
proposed approach can recognize objects more precisely and theperformance outperforms the standard model.

8558-61, Poster Session

An improved algorithm applied to electronic
image stabilization based on SIFTLu Dai, Yuejin Zhao, Xiaohua Liu, Liquan Dong, Bangze Zeng,
Beijing Institute of Technology (China)
Electronic image stabilization, a new generation of image stabilization
technology, obtains distinct and stable image sequences by detecting
inter-frame offset of image sequences and compensating by way ofimage processing. As a high-precision image processing algorithm,
SIFT can be applied to object recognition and image matching,
however, it is the extremely low processing speed that makes it not

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applicable in electronic image stabilization system which is strict withspeed. Against the low speed defect of SIFT algorithm, this paper
presents an improved SIFT algorithm aiming at electronic image
stabilization system, which combines SIFT algorithm with Harris
algorithm. Firstly, Harris operator is used to extract the corners outof two frames as feature points. Secondly, the gradients of eachpixel within the 8x8 neighborhood of feature point are calculated.
Then the feature point is described by the main direction. After that,the eigenvector descriptor of the feature point is calculated. Finally,
matching is conducted between the feature points of current frame
and reference frame. Compensation of the image is processed after
the calculation of global motion vector from the local motion vector.
According to the experimental results, the improved Harris-SIFT
algorithm is less complex than the traditional SIFT algorithm as wellas maintaining the same matching precision with faster processing
speed. The algorithm can be applied in real time scenario. More than
80% match time can be saved for every two frames than the originalalgorithm. At the same time, the proposed algorithm is still valid when
there are slightly rotations between the two matched frames. It is ofimportant significance in electronic image stabilization technology.

8558-62, Poster Session

A SIFT feature based registration algorithm
in automatic seal verification
Jin He, Tianjin Univ. of Technology and Education (China);
Tiegen Liu, Tianjin Univ. (China)
Accurate image registration is the key premise of image analysis
based automatic seal verification. In this paper, a SIFT (Scale
Invariant Feature Transform) feature based registration algorithm ispresented to prepare for the seal verification. The similarities andthe spatial relationships between the matched SIFT feature points
are proposed for the registration of MS (model seal) and SS (sampleseal). SIFT features extracted from the binary MS and SS images,
which have the characters of rotation invariance, advanced stability
and uniqueness, are matched. False matches produce larger errors
if using the least square estimation in the registration of MS and SS.
To further enhance the accuracy and reliability, the false matches
are eliminated by RANSAC (Random Sample Consensus) algorithm.
The position relationship of correct SIFT matches is accurately
estimated by RANSAC, and the homography matrix between the MS
and SS is constructed and named Hs, which defines the positionalcorrespondence between each pair of corresponding points in MS and
SS. The theoretical homography is H. The accuracy of registration isevaluated by the Frobenius norm of H-Hs. In experiments, translation,
filling and rotation transformation are applied to seals with different
shapes, stroke number and structures. The maximum value of the
Frobenius norm of their H-Hs is not more than 0.03. The results provethat this algorithm can accomplish accurate registration of MS and SS,
which is invariant to translation, filling, and rotation transformation, andthere is no limit to the seal shapes, stroke number and structures.

8558-63, Poster Session

A method of contrast enhancement
processing on wide-bits image
Xiang Peng, Zhiyong Xu, Institute of Optics and Electronics(China); Xiaoping Qi, The Institute of Optics and Electronics(China)In order to obtain high-quality images in a project, modern cameras
with wide-bits (12, 14 or 16 bits width) are usually used to acquireenough original information. Nevertheless, some kinds of data selection
and transform processing are necessary to display such images on aPC (8 bits width). Besides, the output image should include both highgeneral contrast and clear details. This paper proposed a methodwith two major steps: for the first step is on the basis of partially

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overlapped sub-block histogram equalization (POSHE), and change
the way of equalizing sub-block image, separate each sub-blockrecursively with different gray ranges. The next step is taking a kind of
pseudo-color processing based on HIS space to enhance the visual
effects, so that the image has rich layers and consistent with human’s
perception. Experimental results show that the algorithm could keep
the local details and the mean of the original brightness at the sametime, enhanced the image effectively. Considered the adaptability on
different scenarios, different objectives, and a reasonable amount oftime complexity, this method could adapt the requirements of practicalengineering applications.

8558-64, Poster Session

Bayer image parallel decoding based on
GPU
Rihui Hu, Zhiyong Xu, Institute of Optics and Electronics (China)
In the photoelectrical tracking system, Bayer images were
decompressed in traditional method, which is CPU-based. However,it was too slow when the images become large, for example,
2Kx2Kx16bit. In order to accelerate the Bayer image decoding,this paper introduces a parallel speedup method based on NVIDA’s
Graphics Processor Unit (GPU) which supports CUDA architecture.
The decoding procedure can be divided into three parts: the firstis serial part, the second is task-parallel part, and the last is dataparallel part including inverse quantization, inverse discrete wavelet
transform (IDWT) as well as image post-processing part. For reducing
the execution time, the task-parallel part run in the CPU in the formof parallel pipeline. The data-parallel part could advance its efficiency
through executing on the GPU as CUDA parallel program. The
optimization technics include instruction optimize, stream asynchronous
technology optimize, texture memory and shared memory conflict
avoid. In particular, it can significantly speed up the IDWT by rewriting
the 2D (Tow-dimensional) serial IDWT into 1D parallel IDWT. Throughexperiments with 1Kx1Kx16bit Bayer image, data-parallel part was
10 times faster than CPU-based implementation. Finally, a CPU+GPU
heterogeneous decompression system was designed. The experimental
result shows that it could achieve 4 to 5-fold speed increase comparedto the CPU serial method.

8558-65, Poster Session

Non-solid hardware three dimensions
display
Junewen Chen, Chung-Hua Univ. (Taiwan)
Screen display is the final and essential apparatus of all the modern 3C
products. And now we have many excellent displays in LCD, OLED,
FED, and 3D screen displays et. al.. Although the display and the
projection display could be simplified to a small rolling sheet or a pieceof paper only, but still all of those displays are solid matters.
We have developed a non-solid type spatially empty three dimensional
display. In a suitable volume of the space, we had theoretically analyzed
and demonstrated the aerial and the fluid dynamics of a stream thatwhen the system is in operation, can be the excellent screen of the
projection display. The physical layout is designed and demonstrated torealize the 360 degree surrounding display of the object. With matching
numerical image data normalization, any sampling model and the actual
person can be displayed with various outfits to be visualized in 360
degree surrounding display and the interactive pose as well. This kindof interactive and addable image display is demanded even more inmany presentation and remote virtual show.
We have in this article present the results of non-solid type spatiallyempty three dimensional display.

8558-66, Poster Session

Analysis of the effect on optical equipment
caused by solar position in target flightmeasureShunhua Zhu, Haibin Hu, Beijing Institute of Tracking and
Telecommunication Technology (China)
Abstract: Optical equipment is widely used to measure flight parametersin target flight performance test, but the equipment is sensitive to thesun’s rays. In order to avoid the disadvantage of sun’s rays directly
shines to the optical equipment camera lens when measuring target
flight parameters, the angle between observation direction and the line
which connects optical equipment camera lens and the sun should be
kept at a big range, The calculation method of the sun’s azimuth andaltitude to the optical equipment at any time and at any place on theearth, the equipment observation direction model and the calculating
model of angle between observation direction and the line whichconnects optical equipment camera lens are introduced in this article.
Also, the simulation of the effect on optical equipment caused by solar
position at different time, different date, different month and different
target flight direction is given in this article.

8558-67, Poster Session

Target azimuth estimation for automatic
tracking in range-gated imaging
Yinan Cao, Xinwei Wang, Yan Zhou, Institute of Semiconductors(China)Active range-gated imaging is widely used in long-range surveillance,
target detection, as well as salvage and rescue at sea, which isdue to its ability of range-finding and good performance in severe
condition. However, target tracking is not only in need of range but
also azimuth, which is necessary to make 3D coordinate of target.
This paper presents a target azimuth estimation method for rangegated imaging system, aiming at obtaining essential information forvision-based automatic tracking. Due to the noise and low contrastof range-gated image, median filter and histogram equalization areused. Then the self-adapted region growing method is performed tomake the segmentation of target and background. After segmentation,
morphologic transformation methods will be taken in order to delete
false targets. With pixels of target extracted from the image, the centoid
will be derived. Next the pinhole camera model is applied to work out
the azimuth coordinate. Since the focus length of camera is needed in
the formula, an NC (Numerical Control) zoom module is developed. In
this module, a sliding potentiometer is connected to the focus motorin camera, which serves as a feedback of the focus length. To read thefocus length and control the focus motor, an MCU (with AD converter)is used. Once the target azimuth information is obtained, the pan-tilt
control unit can track the target bit by bit automatically.

8558-68, Poster Session

Object class recognition based oncompressive sensing with sparse features
inspired by hierarchical model in visualcortexLu Pei, Institute of Optics and Electronics (China) and Shihezi
Univ. (China) and Graduate Univ. of Chinese Academyof Sciences (China); Zhiyong Xu, Institute of Optics andElectronics (China); yu huapeng, chang yongxin, the Institute of
Optics and Electronics, Chinese Academy of Sciences (China)
and Graduate University of Chinese Academy of Sciences(China); shao jianxin, Normal College , Shihezi University (China)
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Conference 8558:
Optoelectronic Imaging and Multimedia Technology II
According to models of object recognition in cortex, the brain uses ahierarchical approach in which simple, low-level features having highposition and scale specificity are pooled and combined into more
complex, higher-level features having greater location invariance.
At higher levels, spatial structure becomes implicitly encoded into
the features themselves, which may overlap, while explicit spatial
information is coded more coarsely. In this paper, the importanceof sparsity and localized features in a hierarchical model inspiredby visual cortex is investigated. As in the model of Serre, Wolf,
and Poggio, we first apply Gabor filters at all positions and scales;feature complexity and position/scale invariance are then built up byalternating template matching and max pooling operations. In order toimprove generalization performance, the sparsity of basis functions isincreased. Similarly, within computational neuroscience, adding sparsity
constraints on the number of feature inputs and feature selection is
critical for learning biologically plausible model from the statistics ofnatural images. Then, a universal dictionary of features that could
handle the recognition of most object categories is designed. By meansof compressive sensing theory and sparse representation algorithm,
object class recognition is implemented quickly and efficiently. The
method is test on the large Caltech dataset of images from 101 object
categories and the UIUC car database. The success of this approachsuggests a plausibility proof for the object class recognition in visualcortex.

8558-69, Poster Session

Multi-limit unsymmetrical MLIBD restoration
algorithm for adaptive optics image
Yang Yang, Information Engineering Univ. (China)
No Abstract Available

8558-70, Poster Session

ENAS-RIF algorithm for image restoration
Yang Yang, Bo Chen, Information Engineering Univ. (China)
Image of objects is inevitably encountered by space-based working
in the atmospheric turbulence environment,such as those usedin astronomy,remote sensing and so on.The observed images areseriously blurred.The restoration is required for reconstruction
turbulence degraded images.In order to enhance the performanceof image restoration, a novel enhanced nonnegativity and support
constrants recursive inverse filtering(ENAS-RIF) algorithm waspresented, which was based on the reliable support region andenhanced cost function.Firstly, the Curvelet denoising algorithm wasused to weaken image noise. Secondly, the reliable object support
region estimation was used to accelerate the algorithm convergence.
Then, the average gray was set as the gray of image background pixel.
Finally,an object construction limit and the logarithm function were add
to enhance algorithm stability.The experimental results prove that theconvergence speed of the novel ENAS-RIF algorithm is faster than thatof NAS-RIF algorithm and it is better in image restoration.

8558-71, Poster Session

Space debris photometric observation
weather impact analysis and processing
verification
Xiao-qin Xu, Beijing Institute of Tracking and Telecommunication
Technology (China)
Photometric variation curve of space debris can provide basic target
identification information. Photometric original data of space target
obtained by photometric observation is the photon flow value within
the atmospheric layer, which is affected by atmospheric conditions,
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observation equipment, detector performance, etc. The influences of
the weather are the most direct cause among these factors. Processing
results of debris photometric data which are obtained by us show thatphotometric variation curve of target fragment is smooth and regular in
the case of metering night, while which is irregular in the night, whichis unsuitable to measure photometric. In addition, it can’t distinguishwhat is the reason of abnormal photometric variation, which may be
the weather or the other reasons. Further analysis results show thatsynchronous monitoring the weather means are available, which canobtain stable photometric variation curve of background fixed star, if
compare it with the photometric variation curve of the main observed
object, we can test and verify the influence factors of the photometricvariation in real time at night when it’s unsuitable for photometricmeasurement.

8558-72, Poster Session

A fast star image extraction algorithm forautonomous star sensors
Xifang Zhu, Feng Wu, Xu Qingquan M.D., Changzhou Instituteof Technology (China)
Star sensors have been developed to acquire accurate orientation
information in recent decades superior to other attitude measuring
instruments. A star camera takes photos of the night sky to obtainstar maps. An important step to acquire attitude knowledge is tocompare the features of the observed stars in the maps with those of
the cataloged stars using star identification algorithms. To calculate
centroids of the star images before this step, they are required to be
extracted from the star maps in advance. However, some large orultra large imaging detectors are applied to acquire star maps for starsensors with the development of electronic imaging devices. Therefore,
star image extraction occupies more and more portions of the whole
attitude measurement period of time. It is required to shorten star image
extraction time in order to achieve higher response rate. In this paper,
a novel star image extraction algorithm is proposed which fulfill thetasks efficiently. By scanning star map, the pixels brighter than the graythreshold are found and their coordinates and brightness are stored in across-linked list. Data of these pixels are linked by pointers, while otherpixels are neglected. Therefore, region growing algorithm can be usedby choosing the first element in the list as a starting seed. New seeds
are founded if the neighboring pixels are brighter than the threshold,and the last seed is deleted from the list. Next search continues until
no neighboring pixels are in the list. At that time, one star image is
extracted, and its centroid is calculated. Likely, other star images may
be extracted, and then the examined seeds are deleted which arenever considered again. A new star image search always begins fromthe first element for avoiding unnecessary scanning. The experiments
have proved that for a 1024?1024 star map, the image extraction takes
nearly 16 milliseconds. When CMOS APS is utilized to transfer image
data, the real-time extraction can be almost achieved.

8558-73, Poster Session

No-reference blur assessment based on
entropy and PCNN for restoration images
Jinping He, Beijing Institute of Space Mechanics and Electricity(China); Jiansheng Chen, Guangda Su, Tsinghua Univ. (China)
In practical problems, there are usually no clear counterparts as
reference to evaluate restoration results. So no-reference blurassessment is very important and necessary. In this paper, we propose
an objective measure named as Edge Factor (EF) to appraise image
blurring.
The fundamental rationale is that blurring effect is much more
perceptible in edge transition zones. If extent of blurring becomes
heavier, the edge transition zones overlap more seriously to neighboring
flat areas. Then some part of edge transition fields fuse into their

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NextConference 8558:
Optoelectronic Imaging and Multimedia Technology IIneighboring flat areas. So, the pixel number of edge transition zones will
decrease. We define the pixel number ratio of the edge transition zones
to the whole image as EF.
In order to count edge pixel number, the point-base entropy (PE) isutilized to transform ramp edges into roof edges to identify the edgetransition zones, and an entropy image is generated. Then Pulse
Coupled Neural Network (PCNN) is used to the above entropy image tosegment edge pixels out.
Root Mean Square (RMS) is full-reference and more convincing.
Comparing RMS, we test the proposed method on images which areblurred with different convolution kernels. Experimental results show
the monotonic consistency of EF and RMS. The proposed method isfurther compared with some common edge detection algorithms todemonstrate the effectiveness of combining PE with PCNN.

8558-74, Poster Session

Impact and application of echo broadening
effect on three-dimensional range-gatedimaging
Xinwei Wang, Yan Zhou, Yuliang Liu, Institute of
Semiconductors (China)
Three-dimensional range-gated imaging (3DRGI) firstly proposed in
the 2000s is a relatively new technique in 3D imaging. It has large
potential in underwater imaging, intelligent surveillance, spatial obstacle
avoidance and aircraft design due to its long range detection, highspatial resolution and effective work through obscurants such as fog,
camouflages or water. 3DRGI has been quickly developed with three
approaches based on depth scanning (3DRGI-DS), range intensity
profile (3DRGI-RIP) and gain modulation (3DRGI-GM). In fact, all 3DRGI
approaches are deduced from slicing images formed by active rangegated imaging. However, in active range-gated imaging there is an
inherent echo broadening effect (EBE) which affects the range intensity
profile of slicing images, and thus the impact of the effect on 3DRGI
should be investigated in order to optimize 3DRGI. In this paper, wegive the spatiotemporal-correlation model of EBE which can directly
display its generation mechanism. Under the spatiotemporal-correlation
model, three typical range intensity profiles of EBE are illustrated under
different temporal parameters of laser pulse and gate pulse. A headzone and a tail zone exist in both sides of the range intensity profile.
Our research demonstrates that EBE should be suppressed in 3DRGIDS and 3DRGI-GM and utilized in 3DRGI-RIP. In 3DRGI-DS, the laser
pulse width had better equal the gate time. In 3DRGI-GM, the laser
pulse width should be much smaller than the gate time. In 3DRGI-RIP,
the laser pulse width and the gate time should be designed according
to the detailed algorithm of 3D reconstruction.

8558-75, Poster Session

Fast range estimation based on active
range-gated imaging for coastal surveillance
Qingshan Kong, Institute of Semiconductors (China); yinan
cao, CAS, semi (China); xinwei wang, youwan tong, yan zhou,
yuliang liu, cas (China)
Coastal surveillance is very important because it is useful for searchand rescue, illegal immigration, or harbor security and so on.
Furthermore, range estimation is critical for precisely detecting thetarget. Range-gated laser imaging sensor is suitable for high accuracy
range especially in night and no moonlight. Generally, before detecting
the target, it is necessary to change delay time till the target is captured.
There are two operating mode for range-gated imaging sensor, one
is passive imaging mode, the other is gate viewing mode. Firstly, thesensor is passive mode, only capturing scenes by ICCD, once theobject appears in the range of monitoring area, we can obtain thecourse range of the target according to the imaging geometry/projecting

transform. Then, the sensor is gate viewing mode, applying micro
second laser pulses and sensor gate width, we can get the range oftargets by at least two continuous images with trapezoid-shaped range
intensity profile. This technique enables super-resolution depth mappingwith a reduction of imaging data processing. Based on the first step, we
can calculate the rough value and quickly fix delay time which the target
is detected. This technique has overcome the depth resolution limitationfor 3D active imaging and enables superresolution depth mappingwith a reduction of imaging data processing. By the two steps, we canquickly obtain the distance between the object and sensor.

8558-76, Poster Session

A comparitive study of temporal phaseanalysis in dynamic speckle interferometry
Hao Zhang, Tianjin Univ. (China)
Dynamic speckle interferometry has been applied to measure vibrationor continuously-deformation. As a promising technique, temporalphase analysis has been applied to dynamic speckle measurement.
In temporal phase analysis, an interferogram sequence is obtainedby a high speed camera during object movement. And the phase is
extracted from the temporal signal.
In this paper, some classical and recently proposed temporal phaseretrieving techniques, such as windowed Fourier transform, wavelet
transform, Hilbert transform, circle fitting in complex plane, arecomparatively studied. The advantage and drawback of each algorithm
are discussed and evaluated in experiments.

8558-77, Poster Session

Research and implementation of real time
image restoration based on phase diversity
Quan Zhang, Changhui Rao, Institute of Optics and Electronics(China); Zhenming Peng, Univ. of Electronic Science andTechnology of China (China); Hua Bao, Institute of Optics andElectronics (China)
Phase diversity (PD) can be used not only as a wave-front sensor but
also a post-detection image processing technology. It makes use of
the methods of optimization and image processing, which can jointly
estimate the phase aberration and image with the focused and the
additional defocused image of the same extended object, however,its computations have been perceived as being too burdensome
and it is difficult to increase the speed of PD to achieve its real time
application on a PC platform.In this paper, we analysed the basic
theory and mathematical model of phase diversity algorithm. Basedon signal estimation theory and optimization theory, we have derived
the cost function of phase diversity method and solved the largescale optimization problem using a limited memory BFGS algorithm.
By comparing the current mainstream computational-hardware, so
we chose the multi-core DSP platform to improve the performanceof PD algorithm. In addition, we used a modified way to the PD
object function which is more easily to deserialize by using DSP.The
experiment results indicate the adopted method is effective to complete
the real-time image restoration.

8558-78, Poster Session

Suishu character recognition based on
genetic fuzzy C-means algorithm
Xu-Guo Zhou, Fang Dong, Jian Xu, Guizhou Industry
Polytechnic College (China)
Suishu character is the very valuable historical and cultural heritage,
but the character recognition system of Suishu is almost a blank. At

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Conference 8558:
Optoelectronic Imaging and Multimedia Technology II
Present, there is no system research about Suishu character recognitionin china. In this paper, the genetic fuzzy C-means algorithm is presented
on based Suishu character feature, meanwhile, the precision ofsegmentation is further improved by using characteristic information
to fuzzy reasoning; Genetic algorithm operator applying in shuishu
character segmentation is analyzed and designed in detail, and thegenetic algorithm is improved to increase convergence speed and avoid
local optimal solution; A neural network classifier is designed for suishu
character recognition; The software system is realized using suishu
character recognition by VC.

the performance metric is calculated according to the image filteredby ABLF. Different level noise and different aberrations are chosen to
testify the validity of AO with ABLF. Numerical simulation results verify
the method is effective and the correction capability of AO with ABLF is
improved more obviously than that of AO without filter or with BLF.

8558-79, Poster Session

Yantao Zong, Xiaoyu Jiang, Academy of Armored ForceEngineering (China)

On-line object tracking method based on cotraining
Jianhong Lai, Zhenming Peng, Univ. of Electronic Science andTechnology of China (China)
The tracking method based on Co-training framework considers
the object tracking as a semi-supervised learning problem. Error
accumulation of the classifier can be effectively avoided in long-term
tracking with this method. However, this method needs a large numberof examples to do off-line training with classifier before tracking.
This paper proposes a new on-line tracking method based on Cotraining framework. First of all, the object is selected as a boundingbox in the first frame, then the bounding box is amplified and we
sampling in it with constant step. The regions surrounding with theobject are added to the positive examples; the regions of backgroundare added to the negative examples. In order to increase the number of
positive examples, we do randomizing affine deformation with original
positive examples. After that, two independent AdaBoost classifiers are
established with the two features, Normalized Moment of Inertia (NMI)and Histogram of Oriented Gradient (HOG). After that, every position
around the object in previous frame is selected as alternative positionof the object in current frame. For every position, two confidencecoefficients are calculated by the two classifiers. After weighting
them, the maximum position is selected as the tracking position of theobject in current frame. The two classifiers exchange their examplesof maximum and minimum confidence coefficients to each other toupdate. Experimental results demonstrate, the on-line tracking method
based on Co-training framework can work robustly in long-term
tracking and the drift of tracking can be effectively avoided.

8558-80, Poster Session

Adaptive bilateral filter for extended object
imaging in adaptive optics system without awavefront sensor
Huizhen Yang, Huaihai Institute of Technology (China)
Extended object imaging is degraded not only by the atmosphericturbulence but also imaging system noise. The noise in image willaffect the value of image quality criteria and further affect the correction
capability of adaptive optics (AO) system without a wavefront sensor.
Therefore, the imaging noise must be processed in order to thecorrection effect of AO system. Bilateral Filter (BLF) can maintain theimage edge and filter noise of image at the same time. Appropriate
parameters are one of the key to removing the noise successfully for
BLF. It is necessary to change the size of parameters adaptively as thenoise level varies. We call such BLF as Adaptive BLF (ABLF).
An AO system with Stochastic Parallel Gradient Descent (SPGD)
algorithm and a 61-element deformable mirror is simulated to restore
the image of a turbulence-degraded extended object and the graylevel variance function acted the optimized object by control algorithm.
Considering the noise level is unknown in practice, we discuss theway of estimating it and then analyze the relationship of parameterswith the noise level. During AO correction, after the noise level being
estimated and parameters being established based on above method,

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8558-82, Poster Session

An improved electronic image stabilization
algorithm

Electronic Image Stabilization use digital image processing technology
to eliminate the jitter of the image in order to gain a clear and stablevideo image sequences.Image motion model is the basis of parameter
estimation, filtering and compensation. Currently, the main model
include translation model, imilarity model, affine model and perspectivemodel. The more of the parameters of the model, the more accurateof the image motion, but the solution time is longer.To improve theof electronic image stabilization algorithm, a variety of image motion
model is studied. The relationship between image shaking and camera
motion is deduced based imaging model. The physical cause of imagetransformation models is indicated. Design a self-adaptive multi-model
electronic image stabilization algorithm, which can choose translation
model or affine model and the corresponding motion estimation method
automatically, by computing the shaking amplitude of image sequences
when camera is working. The experimental result shows that thisalgorithm can achieve high precision stabilization to image sequences,and enhance the abilities of applicability and real-time of electronic
image stabilization algorithm.

8558-83, Poster Session

A novel contour detection method
Rongteng Wu, Minjiang Univ. (China)
Contour detection plays an important role in computer vision. The
importance of building up computational models for the perceptionof contours goes beyond the sole understanding of the human visualsystem. It is a difficult task for us to accurately detect contour of various
image. But contour detection is needed in many practical applicationsof computer vision.
In this paper, we present a novel contour detection method. This
globalization method is run on a boundary posterior probability
detector Pb(x, y) of image. The detector is derived from the local image
brightness, color, and texture channels of each image pixel (x, y). To
build contour detector, the gradient magnitude G is defined according
to a norm. The information of brightness, color and texture of image
is used to generate gradient G and detector. For grayscale image,
only brightness channel is used. Otherwise, the texture channel ofimage need to be defined by assigned an integer id. Using a clustering
algorithm, each pixel will have only one integer id. Moreover, multiscale
cues is used and combined with the three channels to generate G and
detector.
To introduce globalization machinery, spectral clustering is used.
By using the intervening contour cue, a sparse symmetric affinity
matrix is generated and as the spectral clustering stage input. Then
generalized eigenvectors of the system is obtained from spectral
partitioning. The information from different eigenvector is combined into
response spectral component of the detector to generate globalization
information. Finally, the paper shows the experiment results of the
globalization multiscale cues detector compared with other current
detectors.

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8558-84, Poster Session

Wavelength calibration of imaging
spectrometer using atmospheric absorption
features
Jiankang Zhou, Yuheng Chen, Xinhua Chen, Weimin Shen,
Soochow Univ. (China)
Imaging spectrometer is a promising remote sensing instrument
widely used in many filed, such as hazard forecasting, environmental
monitoring and so on. The reliability of the spectral data is thedetermination to the scientific communities. The wavelength position at
the focal plane of the imaging spectrometer will change as the pressure
and temperature vary, or the mechanical vibration.
It is difficult for the onboard calibration instrument itself to keep the
spectrum reference accuracy and it also occupies weight and thevolume of the remote sensing platform. Because the spectral images
suffer from the atmospheric effects, the carbon oxide, water vapor,oxygen and solar Fraunhofer line, the onboard wavelength calibration
can be processed by the spectral images themselves. In this paper,
wavelength calibration is based on the modeled and measured
atmospheric absorption spectra. The modeled spectra constructed by
the atmospheric radiative transfer code. The spectral angle is used todetermine the best spectral similarity between the modeled spectra andmeasured spectra and estimates the wavelength position. The smile
shape can be obtained when the matching process across all columnsof the data. The present method is successful applied on the Hyperion
data. The value of the wavelength shift is obtained by shape matchingof oxygen absorption feature and the characteristics are comparable tothat of the prelaunch measurements.

8558-85, Poster Session

Restoration of nondiffracting image basedon multiple copy images and retinex
Xing Zhong, Hubei Univ. of Technology (China)
An image restoration algorithm based on Retinex theory was proposed
to enhance the image contrast and details for the imaging system of
nondiffracting beams. The proposed algorithm applied the multiple
copy images (MCI) superimposed on the multiple images which thesystem photographed to remove the additive white noise of the image.
Then the processed image will be further processed by the multi-scale
Retinex (MSR) to get the target image. Comparing with the single MCI
or MSR algorithm, the algorithm of MCI combination with the MSR can
get well contrast and clear edge contour. Then the image subjective
visual characteristic was promoted obviously. And it has been
demonstrated by experiment. Thus, the method applied to the imaging
system of the nondiffracting beams for image restoration can meet theimaging and on-line testing requirements.

8558-86, Poster Session

Point target detection based on nonlinear
spatial-temporal filter in infrared image
sequences and its analysis

minimum speed. They are not suitable for detect weak target which
signal-to-clutter (SCR) less than 3 with a low moving velocity.
To solve this problem, a method based on nonlinear spatial-temporal
filter is proposed and analysis its performance. Frist of all, a temporal
filter for detecting point target called triple temporal filter (TTF) is
introduced. Since theoretical analysis shows that TTF has a poor
performance under temporal noise, a nonlinear spatial-temporal filterby neighbor pixels in prior and posterior frames ,which takes every
possible target trace account to suppress noise before coming intorecursion. Then TTF output by positive and inverse sequence order form
nonlinear spatial-temporal filter fuse with liner principle is put forward,
which called bilateral TTF in this paper. Finally after analyzing theperformance of the proposed method, a principle of control parametersettings is built. The results of experiment shows that compared tooriginal TTF, the proposed method achieves a higher signal-to-clutter
ratio gain, which is effectively detecting dim target when target signalto-clutter down to 2.5 or lower with a low moving velocity.

8558-87, Poster Session

Ship target segmentation and detection
in complex optical remote sensing image
based on component tree characteristics
discrimination
Wei Zhang, Research Center for Space Optical Engineering,Harbin Institute of Technology (China); Chunjiang Bian, Xiao
Zhao, Qingyu Hou, Jinnan Gong, Harbin Institute of Technology(China)Automatic ship target recognition in optical remote sensing image has
great application value. With the improved resolution of optical satellite
images, the outstanding advantages of the ship target classification
and recognition in ship investigation, shipping monitoring is attracting
the attention of marine monitoring department and domestic - foreignscholars. Under the application background of sea-surface target
surveillance based on optical remote sensing image, automatic
sea-surface ship target recognition with complicated backgroundis discussed in this paper. The technology this article focused on isdivided into two parts, feature classification training and component
class discrimination. First, the real ship targets and false targets are
selected from remote sensing images as training sample, and theirfeature parameters are extracted. Then the parameters are chosenwith DB Index criterion and a Fisher is used for classification training.
Second, analyzing target/background characteristics of satellite remotesensing images with ocean background, an image segmentation
method based on the component tree is presented, and suspected
targets are obtained by using area - gray (A-L) threshold criteria,then they are input to the trained Fisher classifier to recognize theship target. Experimental results show that the method discussed inthis paper can deal with complex sea surface environment, and can
avoid the interference of cloud cover, sea clutter and islands. For the
panchromatic images from QuickBird and OrbView, the detection
probability of our method is 97.44% and 88.64% respectively. The
method can effectively achieve ship target recognition in complex sea
background.

8558-88, Poster Session

Wei Zhang, Jinnan Gong, Chunjiang Bian, Qingyu Hou, Harbin
Institute of Technology (China)

Template matching and registration basedon edge

In this paper ,we address a problem of detecting weak point target
with low velocity in infrared sequences evolving cloud clutter. Consider
moving objects are viewed at a long range with a infrared electro-opticalsystem, a dim point with slow moving speed is appeared as target insequences. Therefore, its energy is not clearly distinguished between
background clutter, evolving cloud in particular. Former methods basedon temporal processes either have a poor performance or limit the

Qingyu Hou, Lihong Lu, Chunjiang Bian, Wei Zhang, Jinnan
Gong, Harbin Institute of Technology (China)
Image matching aided navigation determines the original matchingarea on the real time image according to template matching, and thendetermines the real time position and attitude of vehicle accurately
using the registration between them to achieve the evaluation of

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Conference 8558:
Optoelectronic Imaging and Multimedia Technology II
precise geometric transformation. Therefore, the final precision of
aided navigation is determined by the precision of image matching
and registration. Considering that the consistency of heterogeneous
image feature and the real-time of algorithm, the edge is regarded
as the feature of matching and registration. A novel edge templatematching measure is proposed based on the point set correlation,termed Weighted Voting Accumulation Measure (WVAM). This measure
is capable of resisting the interference of noise and the similarity region
and can achieve matching location of template edge in heterogeneous
image. On this basis, image registration algorithm based on thesteepest descent of the likelihood function is proposed. The likelihood
function of edge sets registration is established on the basis of Gauss
Mixture Model (GMM) of point sets. In order to achieve the registration
between the template and matching area, and resolve the optimumtransformation parameter by using the steepest descent method, thelikelihood function is regarded as objective function and the affine
transformation parameter is regarded as the optimization variance. And
the experimental results illustrate WVAM has better characteristic interms of global single and local gradient than LTS-HD(Least Trimmed
Square Hausdorff Distance). Meanwhile, compare to the SIDT featurepoints registration algorithm, the results proved that the validity of
proposed algorithm.

8558-89, Poster Session

The simulation for the temporalcharacteristic of the microchannel platesuch M SP ADC CM are serial-parallel connected. The ABC consists of
20-30 CMOS transistors and one photodiode. The ABC has low supply
voltage (1-3.3)V and maximum currents values of 10-40 µA. Therefore
such new principles of realization high-speed low-digital M SP ADC CM
allow reaching a time of transformation less than 20-30nS at 5-8 bits forbinary and Gray codes and general power consumption is 1-5mW. The
quantity of cascadable ??? depends on number of bits n of multi-bits
ADC, and provides quantity of levels of quantization equal to N=2^n.
Such M SP ADC CM has low power consumption ≤3÷5mW even athigh supply voltage (3-7)V, and good dynamic characteristics (frequency
of digitization even for 1,5?m CMOS-technologies is 40 MHz and canbe increased 10 times) and high accuracy (?_quantization=156,25nA
for I_max=10?A). The range of conversion of optical signals, taking into
account sensitivity of modern photo-detectors, is 20-200 ?W. For low
power consumption version of ADC based on only one ABC and ananalog memory block the general power consumption is 50-100µW.
The ADC with serial output bits has no more than 40 CMOS transistors.
The M SP ADC CM opens new prospects for realization linear andmatrix (with picture operands) micro photo-electronic structures which
are necessary for neural networks, digital optoelectronic processors,neural-fuzzy controllers, and so forth.

8558-91, Poster Session

Noise of CCD reduction based on three-D
noise model

Houzhi Cai, Jinyuan Liu, Xiang Peng, Shenzhen Univ. (China)

Hui Lin, Li-Li Liu, Xi’an Institute of Optics and Precision
Mechanics (China)

Microchannel plate (MCP) gated framing camera is a powerful
diagnostic tool for two-dimensional, time-resolved imaging andtime-resolved x-ray spectroscopy in the fields of laser-driven inertial
confinement fusion and fast Z-pinch experiments. Understanding the
behavior of the MCP as used in such camera is critical to understanding
the data obtained. The subject of this paper is a Monte Carlo computercode we have developed to simulate the temporal characteristic of the
MCP. By simulating the electron cascade in the MCP, the relationshipbetween the MCP temporal resolution and the ratio of its thickness tothe channel diameter (L/D ratio) is obtained. The transit time and thetransit time spread (TTS) simulations of the MCP are also presented.
The simulated results show that the transit time and the TTS of the MCP
are increased with the L/D ratio increase while the channel diameter ofthe MCP is 10 um.

During the measuring of laser near field distribution With scientificgrade CCD process, due to the existence of various noises, which will
influence the measurement data degree of confidence. in addition,
when using the near field image to calculate contrast of near-field
optical , require an accurate assessment of effects which science
CCD noise brings, and according to the kind of noise to using different
methods to reduce it. In this paper, the author aimed at the scientificgrade CCD which using in laser parameter measuring system using3-D
noise model, analysed the noise characteristics of CCD, and classified
the CCD noise into temporal noise and spatial noise, then analysed
above two which created in the scientific grade CCD measurement
processing , and using different methods to ruduce noise to get rid of
impact in measurement.

8558-90, Poster Session

Multichannel serial-parallel analog-to-digitalconverters based on current mirrors forthe high-performance image multi-sensor
systems
Vladimir G. Krasilenko, Vinnitsa Social Economy Institute(Ukraine); Aleksandr I. Nikolskyy, Alexander A. Lazarev,
Vinnytsia National Technical Univ. (Ukraine)
The paper considers results of designing and modeling of analoguedigital converters (ADC) based on current mirrors for the multi-sensor
systems with parallel inputs-outputs. Such ADC, named us multichannel
serial-parallel analog-to-digital converters based on current mirrors (MSP ADC CM). Compared with usual converters, for example, reading,a bit-by-bit equilibration, and so forth, have a number of advantages:
high speed and reliability, simplicity, small power consumption, thebig degree of integration in linear and matrix structures. We discuss
aspects of design of M SP ADC CM for Gray and binary codes. We
offered, investigated and simulated M SP ADC CM with 6, 8 and more
bits for Gray and binary codes. Each channel of the overall structure of
M SP ADC CM consists of several base digit cells (ABC). For low power
consumption only one such ABC (less than 20 CMOS) and an analog
memory block are used for the each channel. Base digit cells (???) of

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8558-92, Poster Session

An image threshold based on Burr
distribution
Xiaohong Xie, Rongteng Wu, Minjiang Univ. (China)
Thresholding is a simple and efficient tool for image segmentation.
The aim of thresholding image is to segment image into two oppositeclasses, namely object and background. It is important to accurately
fit the unknown probability density functions of background or
object. The generalized Guassian distribution model is often used
to characterize the statistical behavior of a multimedia signal, andapplied in fitting probability density functions of a signal. But, inpractically, the probability density function of lots of data source may
be inherently non-Gaussian. So simply using the generalized Guassian
distribution model cannot describe the data accurately. This paper will
use Burr distribution to fit the probability density of histograms of the
background and object. Burr distribution is widely used in fitting curvesof reliability distribution for it is more flexible than Weibull distribution
and its three-parameter form is more generalized than log-logistic
distribution. To resolve the estimation difficulty in the Burr distribution
model, the expectation maximization algorithm is used. The expectation
maximization algorithm starts from a set of selected appropriate
parameters’ initial values, and then iterates the expectation-step andmaximization-step until convergence. The experiment results show thatthe Burr distribution could depicts quite successfully the probability

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density function of a significant class of image, and comparatively themethod has low computing complexity.

8558-93, Poster Session

Evolution of the square pattern in dielectricbarrier discharge
Yongjie Wang, North China Electric Power Univ. (China); Lifang
Dong, Hebei Univ. (China)
Dielectric barrier discharge (DBD) is a kind of nonequilibrium gas
discharge, which has been well known for its widespread industrial
applications, such as ozone generation, biomedical applications,polymerization process, surface treatment and plasma display panels.
Recently, much attention has been paid to DBD due to various
kinds of pattern formation, including square, hexagon, spiral, andconcentric-ring pattern. In addition, DBD has the unique advantage oflight emission feature, which leads to the fact that the spatiotemporal
dynamics of patterns can be studied with the optical method.
Especially, the intensified charge-coupled device (ICCD) camera isalways used to study the evolution of the discharge in DBD.
In this paper, the square pattern is obtained under small boundary
condition in DBD. The spatiotemporal dynamics of the square patternis investigated by the ICCD camera for the first time. The ICCD camera
is triggered by a generator of rectangular pulses, which is synchronizeddirectly by the discharge current signal. By varying the delay between
the discharge current and the opening of the ICCD’s gate, we can track
the temporal evolution of the discharge. Each image is taken during
one single discharge current pulse of 200ns and not overlapped with
the images in other cycles. It is found that there are two discharge
current pulses in each half cycle of the applied voltage. The square
pattern is an interleaving of two transient sublattices, which appears at
different times. In two consecutive half cycles of the applied voltage,
the temporal evolution of the two sublattices is inverted. The results
show that the wall charges play an important role in the evolution of thesquare pattern.

8558-94, Poster Session

CT/MR medical image fusion based on fuzzyalgorithm
Weidong Lai, Hebei Univ. (China); Xiaojun Wang, North China
Electric Power Univ. (China)
The use of imaging as an assay in the medical fields, such as computer
tomography (CT), magnetic resonance (MR), ultrasound, etc., relies
on either manual interpretation, or algorithms developed specificallyfor the image type and subject. Automated, robust, and quantitative
image analysis methods are in great demand. The translating accuracy
achieved from the images extensively depends on the quality ofimages. But it is unfortunate that the medical images, such as CT, MR
etc., are often limited by the isolated feactures in respective image,which is ascribed to its unique image acquisition technique. For many
applications, the information directly provided by single medical
images is incomplete. In order to enhance the diagnostic accuracy,
image fusion is the fundamental process when aiming at interpreting
integrated medical information. In this paper, the combined wavelet
transform and fuzzy fusion algorithm is put forward to extract and fuse
the feactures of CT and MR images. After discussion of the defects
from ordinary fusion methods, the 3-level wavelet transformation is
proposed for extract image feactures, based on the considerationthat the image edge signal exists in high frequency wavelet domain
and the local details in low domain. Furthermore, the high freqnency
wavelet coefficients of CT and MR images are fused by manipulating
the respective coefficients according to the local variance, while thelow frequency coefficients are fused by fuzzy rule proposed in thispaper. The most important factor in the proposed fusion rule is the fuzzy
density betweenthe respective CT and MR coefficients, which is put

forward by analyzing the statistic characteristic of such coefficients.
By adjustment of the coefficients of the different wavelet domain,
the edges and the details from CT and MR are fused and preserved.
Simulation indicates that the combined algorithm can effectively
fuse the medical images, and the information entropy is calculated
to compare the different fuzzy density rule. The combined algorithm
proposed in this article can be integrated in medical image analyzing
software to obtain higher accuracy for symptom interpretation andmultisource fusion.

8558-95, Poster Session

Restoration of ultrasound image based on
novel morphology operator
Xiaojun Wang, North China Electric Power Univ. (China);
Weidong Lai, Hebei Univ. (China)
Information detection and recognition of nidus have been playing
important roles during clinical pathology, which can not only be attained
through the general reports such as auscultation, palpation andthermometric analysis, but also by the advanced multi-images from the
X-rays, CT (Computerized Tomography), MR (Magnetic Resonance) as
well as US (Ultrasound), etc.. Since the medical images can expose
the inner structure of the body without significant damages to human
body, the medical images have been accepted as the major diagnostics
supports in modern clinical medicine. Though all medical images haveessential meaning for acquiring the nidus information, the ultrasoundtechnique can be easily generalized in low cost, especially in thedeveloping countries. Ultrasound has increasingly been used as firstaid response for emergency cases. Furthermore, ultrasound is acted
as remote diagnosis means where teleconsultation is required. Due tothe complex composition of human body organs and the air bubble
environments, the ultrasound images are inevitably deteriorated bynoises from variance sources to generate the echo texture, speckle
noise and weak edges. In order to enhance the signal as well asheightening the diagnosis accuracy, many algorithms have been
investigated and practiced. From morphology viewpoint, the ultrasoundimage is constructed by pixels with grey levels image presented as
different gradient magnitude. Image morphological segmentation isimportant for clinically computer vision that aims to segment the image
into physically meaningful regions. In this paper, the ultrasound image
is analyzed that the edge of tissue is formed as continuous pixels, with
the noise points presenting as discrete variability pixel. Based on suchanalysis, modified Susan operator is proposed by judging the validityof the edges, and extracting the ultrasound information through noisebackground. The window width and window format of Susan operator
is adjusted, with the weight in window matrix also optimized, to theedge detection resolution. As comparison, the traditional filter method,such as differential operators, the median filtering algorithm as well as
wavelet transformation is also practiced. Results show that the SUSAN
edge detector finds image features by using local information from apseudo-global perspective. And the proposed method is superior toother methods in both noise reduction and detail preservation. The
proposed algorithm can be integrated in expert system for ultrasoundanalyzing.

8558-96, Poster Session

The effect of chromatic background forluminance contrast-sensitivity function
Li Song, Ningfang Liao, Shuwen Dong, Ting Liao, Weigui Hu,
Kai Lin, Beijing Institute of Technology (China)
In the study of human contrast sensitivity, it is mainly measured inthree channels: luminance, red-green and yellow-blue. It is based on
the assumption that the luminance signal and the chromatic signal
are independent. However, there have some results shown that
there may be some internal relation between the luminance signal
and the chromatic signal. Therefore we study the effect of chromatic

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Conference 8558:
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background on luminance contrast-sensitivity function (CSF). We
selected three background-grey, orange and yellow-green from CIE 17
color center and the mean luminance of these colors are 29.6 cd/m2,
30.6 cd/m2 and 33.2cd/m2, which are approximately equal. We use
CRT monitor display the rectangular stripe. In order to let the minimum
contrast is below 0.003, the dither technology was used in producing
rectangular stripes. The minimum contrast we produced is 0.0025.
Every rectangular stripe has six spatial frequencies, they are 0.4, 1, 2,
3.5,7 and 14 cycles/degree (cpd).The psychophysical method of limits
is used in the experiment, 5 observers, who have normal vision and testof vision are all over 1.0, participated in the experiment. The results ofexperiment show that the luminance contrast sensitivity on chromaticbackground is lower than the luminance contrast sensitivity under grey
background. We finally used two mathematics models-Barten modeland Movshon model to fit the psychophysical data. Fitting result showthat Movshon model is better than Barten model, especially for thechromatic background. Both of the models have deviation in the highspatial frequency part.

8558-29, Session 6

Probability voting and SVM-based vehicle
detection in complex background airborne
traffic video

typically defined as the task of jointly segmenting “something similar” ina given set of images. We can divide the human gait images sequence
into several steps and every step consist of 10-15 frames. The frames
in human gait images sequence have following similarity: every frame
is similar to the next or previous frame; every frame is similar to thecorresponding frame in the next or previous step. The progress ofcosegmentation based human silhouette extraction can be describedas follows: Initially only points which have high contrast to backgroundare used as kernel points, then every kernel point will grow using theimage similarity information. We define a global energy function G toconstraint the growth of the kernel point. The definition of G consider
the constraint of the maximum size of a human, the maximum frames
count in one step and the Markvo random field modeling. Experimental
result shows that our method has a better performance comparing totraditional human silhouette extraction methods.

8558-31, Session 6

An Adaboost based approach for ship
detection in remote sensing images
Junli Yang, Jiang Zhiguo, BeiHang Univ. (China)

Bo Lei, Huazhong Institute of Electro-Optics-Wuhan National
Lab. for Optoelectronics (China); Qingquan Li, Wuhan Univ.
(China); Zhijie Zhang, Chensheng Wang, Huazhong Institute ofElectro-Optics-Wuhan National Lab for Optoelectronics (China)

In this work, we address the problem of ship detection in remotesensing images, which is crucial in ocean surveillance, marine traffic
security, sea pollution monitoring, and protection against illegal fisheries
and oil discharge. Remote sensing images exhibit highly complicatedbackground and contextual information. Most state-of-the-art ship
detection methods suffer from long detection time, high false detection
rates and unsatisfying detection rates.

This paper introduces a novel vehicle detection method combined withprobability voting based hypothesis generation (HG) and SVM based
hypothesis verification (HV) specialized for the complex backgroundtraffic video captured by the camera on an airborne platform. In thestage of HG, a statistic based road area extraction method is applied
and the lane marks are eliminated by morphological operations.
Remained areas are clustered by different area growth method
according to whether the processed scene is a high or low velocity
scene. Then the canny algorithm is performed to all of the clusteredareas to detect edges. Every pixel in these edges votes for a square
area which is presumed to contain the center of a vehicle. This voting
strategy is designed to detect rectangle objects in the scene. The voteof every pixel is counted to form a voting image, and the center of a
possible vehicle always takes a high value, which indicates a vehicle
hypothesis. In the stage of HV, every possible vehicle area is rotated toalign the vehicle along the vertical direction, and the vertical gradientsand the horizontal gradients of them are calculated, which are projectedto the horizontal direction and vertical direction respectively. In order toperform classification, several features are defined, which include thelength and width of possible vehicle, peaks of the vertical projection,etc. SVM is adopted to classify vehicle and non-vehicle. The proposed
method has been applied to several kinds of traffic scenes, and theexperiment results show it’s effective and veracious for the vehicle
detection of the given scenes.

The proposed method was tested on Google earth images containing
ships or ship plumes. The experimental results show that our method
has good performance in detection accuracy and convergence speed.

We present a machine learning approach for real-time ship detection
in remote sensing images that is extremely rapid and can achieve highdetection rates. In the approach we use a boosted cascade of simple
classifiers under the Adaboost framework. First, in the AdaBoost basedlearning process, which is carried out off-line to speed up the detection
process, we pick a small number of critical features from a large featurepool and acquire highly efficient classifiers. Second, to implement
the multi-direction and multi-scale detection, we need to collectcorresponding training samples to train a classifier in each orientationand scale, which is a time consuming work. To save the training datacollection time, we train a classifier in only one direction and turn thetesting image direction in every 10 degrees to be detected by theclassifier, and superpose the detection results in all the orientations.
Then a clustering method is used to get the final detection result. As
for the multi-scale implementation, the similar principle is employed, inwhich the only difference is to lessen the testing image. Thirdly, to makethe feature calculation faster, we employ an image representation called
Integral Image which largely simplifies the Haar feature computation.
At last, the introduction of “cascade” allows us to combine increasingly
complicated classifiers, which can quickly discard the backgroundregions and spend more computation on promising ship-like regions.

8558-30, Session 68558-32, Session 6

Silhouette extraction from human gait
images sequence using cosegmentation

Bottom-up attention based on C1 features of
HMAX model

Jinyan Chen, Yi Zhang, Tianjin Univ. (China)
Gait based human identification is very useful for automatic person
recognize through visual surveillance and has attracted more and more
researchers. A key step in gait based human identification is to extract
human silhouette from images sequence. Current silhouette extraction
methods are mainly based on simple color subtraction. These methods
will have a very poor performance when the color of some body parts
is similar to the background. In this paper a cosegmentation based
human silhouette extraction method is proposed. Cosegmentation is

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Huapeng Yu, Zhiyong Xu, Chengyu Fu, Institute of Optics andElectronics (China); Yafei Wang, Univ. of Electronic Science andTechnology of China (China)
This paper presents a novel bottom-up attention model only based on
C1 features of HMAX model, which is efficient and consistent. Althoughsimilar orientation-based features are commonly used by most bottomup attention models, we adopt different activation and combination
approaches to get the ultimate map. We compare the two different
operations for activation and combination, i.e. MAX and SUM, and we

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argue they are often complementary. Then we argue that for a generalobject recognition system the traditional evaluation rule, which is theaccordance with human fixations, is inappropriate. We suggest newevaluation rules and approaches for bottom-up attention models, which
focus on information unloss rate and useful rate relative to the labeledattention area. We formally define unloss rate and useful rate, and findefficient algorithm to compute them from the original labeled and output
attention area. Also we discard the commonly adopted center-surroundassumption for bottom-up attention models. Comparing with GBVS
based on the suggested evaluation rules and approaches on complex
street scenes, we show excellent performance of our model.

coordinates. This paper proposes a method using the signal adjacentto the signal peak to estimate its location. Because the low resolution
images are undersampled and have aliasing effect, the performanceof conventional registration methods decreases. This paper presents
a method to eliminate the influence of aliasing. Excellent results havebeen obtained for subpixel translation estimation of synthetic image
sequence. The algorithm is also compared to other algorithms. The
error analyses show that the proposed algorithm is more robust andhave higher precision.

8558-33, Session 6

An illumination and affine invariant
descriptor for aerial image registration

Normalization of the collage regions of
iterated function systems
Zhengbing Zhang, Wei Zhang, Yangtze Univ. (China)
Fractal graphics, generated with iterated function systems (IFS),
have been applied in broad areas. The generated graphics is actually
the attractor of the IFS. Since the rectangle regions containing
the attractors for different IFS may be different, it is impossible torespectively show the attractors of different IFS in a same region on
a computer screen using one program without modifying the display
parameters. A method is proposed in this paper to solve this problem
by normalizing the collage regions of IFS. An IFS is defined as a finite
set of contractive affirn mappings. The fixed point is calculated for eachmapping, and the minimum rectangle region containing all the fixed
points is called as the characteristic rectangle of the IFS. The symbol
X is used to represent the unit square with the upper-left corner at (0,0) and the lower-right corner at (1, 1). The collage region of an IFS isdefined as the minimum rectangle that contains all the quadrangles
transformed from X by its affirn mappings. Proposed algorithm: (1) Atransform T(0) determined according to the characteristic rectangleof the IFS and X is used to modify the IFS coefficients so that thecharacteristic rectangle of the resulted IFS, denoted by IFS(0), changes
toward X; (2) If the collage region of IFS(i) is represented with R(i), thena transform T(i+1) determined according to R(i) and X is used to modify
the coefficients of IFS(i) so that R(i+1) of the resulted IFS(i+1) changes
toward X, where i goes from 0 up until the required result is obtained.
Experimental results demonstrated that the collage region of any IFS
can be normalized to the unit square with the proposed method.

8558-37, Session 7

Zhaoxia Liu, Yaxuan Wang, Yu Jing, Jing Zhao, Dalian Univ.
of Foreign Languages (China); Jingjing Wang, Liaoning Police
Academy (China)
An illumination and affine invariant descriptor is proposed for registering
aerial images with large illumination changes and affine transformation,
low overlapping areas, monotonous backgrounds or similar features.
Because K-nearest neighbors (K-NN) graph and the corresponding
adjacent graph are invariant to affine transformation, in this paper, they
are used for generate the triangle region with initial matched result
by Scale-Invariant Feature Transform (SIFT). In order to improve theaccuracy, three means of region growth, which is invariant to affine
transformation, is applied to boost small and slender triangles. Thena new triangle area based illumination and affine invariant descriptor
is defined to describe the triangle regions and measure their similarity.
The descriptor is the combination of MultiScale Autoconvolution (MSA)
and multiscale retinex (MSR). In the description, illumination invariant isobtained by MSR removing the illuminance of the image, and reflective
image is obtained and replaces the original image. Then MSA, whichcomes from the idea that the corresponding regions have the same
intensity distribution and their mathematic expectations are invariant
to affine transformation, is applied to describe the triangle regions
obtained from reflective image. The performance of the descriptor
is evaluated with optical aerial images and the experimental results
demonstrate that the proposed descriptor is more distinctive than MSA
and SIFT.

8558-38, Session 78558-35, Session 7

A subpixel motion estimation approachbased on phase correlation
Hui Yu, Huazhong Univ. of Science and Technology (China);
Fusheng Chen, Zhijie Zhang, Chensheng Wang, Huawang
Chen, Huazhong Institute of Electro-Optics-Wuhan National Lab
for Optoelectronics (China)
Image registration is a process of overlaying two or more images ofthe same scene and differing from each other due to displacement,
rotation, scaling, etc. Image registration is a crucial step in various
image fusion tasks, such as super-resolution. For the success ofimage super-resolution reconstruction, it is essential to find out highaccurate subpixel motion estimation between images in the input
sequence. This paper proposes a frequency domain-based motion
estimation algorithm for the under-sampled infrared images. Only
the pure translational motion is considered, because the rotation andscaling estimation can be converted into the translational motion
estimation using the log-polar transform. The proposed algorithm isbased on the phase-only correlation which is defined as the inverse
Fourier transform of the normalized cross power spectrum. The
signal peak of phase-only correlation shall locate at the coordinate
which is the number of transformed pixel between the two images.
Because of the use of discrete Fourier transform and the subpixel
displacement, the signal peak is not always concentrate in the integer

Manifold representation of multi-view
imagesHaopeng Zhang, Zhiguo Jiang, Junli Yang, BeiHang Univ.
(China)Images of the same object lie on a low-dimensional manifold in thevisual space. The manifold that multi-view images of an object lie on
can be called view manifold. learning such manifold could be very
helpful to multi-view object detection, classification, and viewpoint
estimation. In this paper, we use view manifold to represent viewpoint
variation of multi-view images in the embedding space. The view
manifold can be obtained by current manifold learning methods, suchas Isomap, LLE, LE, etc., with proper image features as inputs. In
order to evaluate the performance of the learned view manifolds, wefirstly analyze the topological property of these manifolds using somemathematical measures, and then learn a generative model that can
map from the manifold representation to visual inputs for arbitrary view
image synthesis and viewpoint estimation. We did experiments on bothsynthesized dataset and real dataset which contained images with
1D or 2D viewpoint variation. Five popular manifold learning methods
were used in our experiments with different kinds of image features
as inputs. Experimental results show that manifold representation caneffectively describe the viewpoint variation of multi-view images, andperform successfully on arbitrary view image synthesis and viewpoint
estimation.

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Conference 8558:
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8558-39, Session 8

Tire x-ray image belt-ply defect feature
recognition method based on Gaborwavelets
Qiang Du, Qingdao Mesnac Co., Ltd (China) and Tianjin Univ.
(China)A novel method was developed for belt-ply defect feature recognitionof tire X-ray image which is characterized as overlapped textures. Tire
X-ray image contains complex texture which is caused by overlapped
multi belt-plies, it is difficult to get defect information around thelocation of complex texture. The spectrum of each belt-ply texture
are separable due to different location of each dominant frequencies
corresponding to different belt-ply in 2D frequency space, 2D Gaborwavelet is used to separate the spectrum which belongs to different
belt-ply texture, after extracting different belt-ply texture of tire X-ray
image, each result single texture image is calculated through grey levelstatistic on vertical orientation to get a 3D model which contains detaildefect information, such as texture location, orientation and bend levelstatus. The experiment results show that every belt-ply texture can beseparated accurately, and the recognized texture features are accurate
and help estimate tire defect correctly according to the result 3D model.

8558-40, Session 8

A three-dimensional cursor used in binocularstereo vision
Hong Jiang, Bo Yuan, Liqiang Wang, Zhejiang Univ. (China)
A three-dimensional (3D) cursor, which is used to locate an object in
the binocular stereo vision system and measure the distance fromthe object to camera, was proposed in this paper. The 3D image iscomposited of one left-image and one right-image captured by thebinocular cameras and is displayed in a 3D liquid crystal TV. The leftcursor, whose position is controlled by the mouse, is generated andconstrained in the left-image. Then, the matched point in the rightimage with the current position of mouse in the left-image is detectedby an effective key-point matching algorithm, and the right-cursor isgenerated on this matched point. At last, the left-cursor and rightcursor are mixed to a 3D cursor, which is able to select the target in the
3D image; meanwhile the distance is calculated by the parallax between
the pair points. The above algorithm for generating the 3D cursor
was realized using the own program compiled by C sharp language.
The effect of 3D cursor was tested in the self-build binocular stereo
camera. The results show that the 3D cursor is distinct to select thetarget accurately and the real-time distance measurement is realized.
Moreover, our method is low-cost with little requirements for hardware.

average variance for low frequency sub-band, the secret bits can be
guaranteed to be embedded in the regions which is not sensitive forhuman eyes. Secondly a secret key matrix is proposed and shared by
the sender and receiver with the seeds of random number generator.
We try to find a suitable vector, which multiplied by the matrix equals
to the secret bits vector. And all the values in the suitable vector are
adaptively embedded into wavelet coefficients of image subbands with
wet paper code. Secret information receivers do not need to know thespecific method of secret writing, just do a simple matrix multiplication
operation and can extract the secret information, which in many ways
to improve the security of the steganographic algorithm. Finally, theexperiments show that the method has good visual invisibility andresistance against active steganalysis attacks.

8558-42, Session 8

A visible/infrared gray image fusion
algorithm based on the YUV colortransformation
Zhu Jin, Weiqi Jin, Jiakun Li, Li Li, Beijing Institute ofTechnology (China)
Color fusion technology is one of the typical technologies that has beenemphasized in domestic and foreign countries by fusing multiband
images into a color image. It’s suitable for observation and target
detection. Effective visible and thermal infrared color fusion algorithms
have been proposed now. We have successfully run the natural senseof color fusion algorithm in DSP and FPGA hardware processing
platform real-time. However, according to different needs, gray-scale
video fusion technology has its own unique applications.
Based on the natural sense of color image fusion algorithm of thevisible and infrared, we have studied a based on the YUV color passed
visible / infrared gray image fusion algorithm. Firstly we do a YUV color
fusion (Threshold of weighted fusion and color transfer of the reference
image). Then we output the brightness of the fusion (Y channel) as grayscale fusion images. This algorithm for image fusion is compared withregular fusion algorithms: the weighted average, the Laplace Pyramid
and the Haar basis wavelet. Selected objective evaluations for fusion
are information entropy, joint entropy, cross entropy, root mean squareerror, peak signal to noise ratio and mutual information. The objective
and subjective comparing results show that this algorithm compared tothe traditional usual algorithm has most advantages.
On the basis of the Matlab simulation, the algorithm is implemented
on a DSP hardware image processing platform real-time with the TI’s
chip (TMS3200M642) as the kernel processor. It makes natural sense ofcolor fusion and gray fusion for visible light (low level light) and thermal
imaging integrated. Users are convenient to choose model of thenatural sense of color fusion or gray fusion for real-time video imaging
output according to their needs. It provides a flexible choice for theapplication of high-performance visible/infrared fusion imaging system.

8558-41, Session 8

Steganograpy based on human visualsystem with wet paper codes
Zhihong Chen, Tianjin Univ. (China); Lili Cao, Tianjin Univ. ofTechnology (China)
Steganography algorithms are often on the basis of different coverimages types, transform domain and so on to design different
embedded measures, which is to achieve the best performance, suchas high capacity, low visibility and high robust.
Wet paper code is a complex model which mainly used in the fieldof image coding. This paper is based on the researches of wet
paper code model and human visual system, and constructs a newsteganographic method. Firstly we design a new select channel insteganography. Through the calculation of local mean square value
for all wavelet subbands in 2x2 neighborhood and the corresponding

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8558-43, Session 8

Liver hydatid CT image segmentation basedon localizing region active contours method
and modified parametric active contour
model
Jianjun Chen, Murat Hamit, Yanting Hu, Xinjiang Medical Univ.
(China); Yanting Hu, College of Medical Engineer Technology of
Xinjiang Medical University (China)
Liver hydatid is a high incidence endemic disease in XinJiang and
CT Image segmentation of focal area has important role in clinicaldiagnosis. Based on CT imaging features of this disease, localizing
region active contours method and modified parametric active contour
model is proposed. The presented technique is is very suitable for
localization active contour energy and our segmentation framework canmake accurate segmentation of focal area. by using known intensity
information into the image model incorporating modified parametricactive contour model, it can handle problems where the interi or
exterior of the image of Liver hydatid has a highly inhomogeneous
intensity distribution. Its feature term is computed locally. This
property allows the algorithm to segment nonhomogeneous objects.
We reduce the method sensitive to initialization through the modified
parameters and evaluate the algorithm from subjective and objective
aspects on different patients’ CT slices. By comparing our algorithm
segmentation to ground-truth manual segmentation, the results show
the effectiveness of our method to segment liver and hydatid lesion.

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Conference 8559:
Information Optics and Optical Data Storage II
Tuesday - Wednesday 6 –7 November 2012
Part of Proceedings of SPIE Vol. 8559 Information Optics and Optical Data Storage II

8559-4, Poster Session

A novel high-speed opto-electronic hybrid
correlator for recognition and tracking
Jinggao Sui, Xiaoya Zhang, Wusheng Tang, ChenCheng Feng,
Jia Hui, National Univ. of Defense Technology (China)
Opto-electronic hybrid correlator can realize the combination ofelectronic flexibility and high speed of optical computing, so it
has widely potential applications in high speed optical information
processing system, especially recognition and tracking system. But
the opto-electronic conversion speed and the positioning accuracyof correlation peak constrains the performance of this system. This
paper first proposes an idea that PSD(Position Sensitive Device) canbe applied in optical correlation peak detection instead of traditional
CMOS sensor. It is displayed by experimental data that this system
can attain a correlation calculation speed of 20,000 frames per second,which indicates that the system can satisfy high speed demands oftarget recognition and tracking. Through optimal design of Fourierlens, the size, shape and intensity of the correlation peak spot havebeen optimized to satisfy the positioning accuracy requirement of PSD.
Because the property of PSD can lead to nonlinear displacement errorof the correlation peak, a new correlation peak compensation algorithm
is brought up to compensate the error. The experimental results
indicate that positioning accuracy of correlation peak can be promoted
five times compared with the original outcome, which reduces theinfluence of nonlinear displacement error of the correlation peak on thisrecognition and tracking system sharply. In conclusion, a high speed
and high accuracy recognition and tracking system has been realizedbased on the opto-electronic hybrid correlator.

8559-17, Poster Session

Recognizing and recording the tone ofpeople and others’ language to promote
development of work, life, and science, andto promote administration of social security

practical gaining could be great.
The breakthrough technology project of computer science can be used
for recognizing and recording the tone of language of other biology,
and their characters of the speaking or voice information, apart frompeople’.

8559-18, Poster Session

Hydrogen bonded supramolecularazopolymers: A media for multilayered andpolarization-multiplexed data storage basedon two-photon process
Daqiao Hu, Yanlei Hu, Wenhao Huang, Qijin Zhang, Univ. of
Science and Technology of China (China)
A two-photon induced high density information storage is demonstrated
in hydrogen bonded supramolecular azopolymers.Supramolecularazopolymers are prepared through strong hydrogen bonding interaction
between pyridine moiety of poly (4-vinylpyridine) (P4VP) and phenol
moiety of 4-nitro- 4’-hydroxyazobenzene (AzoOH). The content of azo
chromophore is tuned easily and it can achieve a high concentrationas 69.4wt% in P4VP (AzoOH)1.0 complexes. FT-IR spectrum verifies
the hydrogen bonding has formed between them. High quality ﬁlms
of the supramolecular P4VP (AzoOH)1.0 complexes are obtainedby spin-coating. A multilayered optical recording medium using the
supramolecular azopolymer and a transparent ﬁlm has been developed
for two-photon recording. The thicknesses of the photosensitive layers
and the transparent layers are 500nm and 12 ?m, respectively. A linearlypolarized Ti:Sapphire femtosecond pulsed laser (wavelength: 800 nm,
pulse duration: 80 fs, and repetition rate:80 MHz) is used as a recording
beam to induce anisotropy, and the recorded information is readout
by transmission microscope with a polarized white light. Multilayered
and polarization-multiplexed data storage has been demonstrated byusing the method. The capability to combine both advantages of these
distinct techniques in supramolecular azopolymer films makes it a novel
media for higher optical data density.

Xu Han-You, Workers’ Hospital of Nanyang Textile Corp. (China)

8559-19, Poster Session

Objective: In this paper, the author outlined a new breakthroughcreation of project for information and computer science. Which use themodern information and computer science to solve the present problem
which the computer has not recorded all the tone and the words at thesame time when the people are speaking.

Simulation results of optoelectronic
photocurrent reconfigurable (OPR) universal
logic devices (ULD) as the universal
circuitry basis for advanced parallel highperformance processing

Method: Summarize the modern information and computer science.
Create the new breakthroughs project of computer science.
Results: The author outlines, by developing a new technology project
to recognize the people’s speaking and their tone and characters, atthe same time, transmit the recognizing into computer with their tone
and characters and store the tone and characters of the speaking
information. Therefore, any people’s speaking could be recorded into
the computer with their characters of tone at the same time.
Conclusion: This is a breakthrough creation project for information andcomputer science. When the breakthrough creation came into reality.
The revolution movements of science could be induced. The life, work,and security and other active things of mankind could be more easy
and wonderful. There were much too harvesting in economical andpractical gaining. And there were also much too harvesting in social
development. So there are lots of chances waiting us to make her truein the near future when the paper of the new breakthrough creation
for information and computer science is published and accepted for
application. Because recognizing and recording the tone of people’
language and his characters of the speaking information are different
from each other. Like the fingerprint, the public security and other

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Vladimir G. Krasilenko, Vinnitsa Social Economy Institute(Ukraine); Aleksandr I. Nikolskyy, Alexander A. Lazarev,
Vinnytsia National Technical Univ. (Ukraine); Taras E. Magas,
Vinnitsa Social Economy Institute (Ukraine)
The conception of construction of the family of the offeredoptoelectronic photocurrent reconfigurable (OEPR) universal or
multifunctional logic devices (ULD) consists in the use of a current
mirrors realized on 1.5?m, 0.35?m, 65nm technology CMOS transistors.
Presence of 18-40 transistors, 1÷5 photo-detectors makes the offeredcircuits quite compact and allows their integration in 1D and 2D arrays.
In the presentation we consider the whole family of the offered circuits,
show the simulation results and possible prospects of application of thecircuits in particular for time-pulse coding for multivalued, continuous,neural-fuzzy and matrix logics. The simulation results of the NOT,
AND, OR, OR-NOT, XOR optoelectronic photocurrent logical elements(OEPLE) and OEPR ULD on the 1.5?m, 0.35?m, 65nm technology
CMOS transistors showed that the level of logical unit can change

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Information Optics and Optical Data Storage IIfrom 20nA, 50nA, 500nA 1?A to 10?A for low-power consumption
variants and from 20-500nA to 1-10?A for high-speed variants. We
have developed schemes OPR ULD which realize the universal binary
logic from optical signals. They have subpixel a configuration from 2x2
elements, consist of a small amount of photo diodes (4) and transistors(18), have low power consumption <1µW-5mW, high productivity
and realize the basic set of operations of continuous logic with time
pulse representation of processed signals. Modeling of such cells in
OrCad is made. It is confirmed that all set of possible functions will
be realized such OEPLE and OEPR ULD by a simple photo-tuning.
Such base cells are integrated into arrays 32?32 and allow reachingproductivity 10^12 CL-logic operations/sec. The results of design ofoptoelectronic processors (OEP) with used ULD as base cells for 1D
and 2D computing mediums are considered in the chapter. We consider
and show that the OEP and all principal components of OEP canbe implemented on the basis of optoelectronic photocurrent logicalelements (OEPLE) and OEPR ULD.

8559-20, Poster Session

Pattern recognition by Mach-Zehnder joint
transform correlator with binary power
spectrum
Chengyu Liu, Chulung Chen, Weichih Liao, Sihliang Fu, Yuan Ze
Univ. (Taiwan)
We propose a construction of the Mach-Zehnder joint transform
correlator with binary power spectrum for target recognition, and apply
liquid crystal spatial light modulators to this system. In addition, we
utilize the minimum average correlation energy method and multi-level
quantized reference function. The constructed reference function isdesigned to be implemented at the input plane. Numerical result ispresented.

8559-21, Poster Session

Optical correlation recognition research of
low light level target based on lifting wavelet
transform
Qibo Zhang, Su Zhang, Wensheng Wang, Changchun Univ. of
Science and Technology (China)
Optical correlation technology is an important application in target
recognition field, which can apply Joint Transform Correlator to achievetarget recognition.
For the low light level target with low contrast and backgroundnoise interference, using optical correlation method may reduce therecognition ratio and lead to the correlation peak not sharp in the
optical experiment. In order to solve the problem, the wavelet transform
applied to low light level target image processing is an effective
method. However, the traditional discrete wavelet transform basedon convolution has large amount of calculation, high computational
complexity and large storage space requirements. Lifting wavelet
transform is used to solve this problem successfully.
This paper proposes a new algorithm-adaptive directional lifting basedon wavelet transform. Low light level image enhancement and edge
extraction are applied in this algorithm. Firstly, low light level image isdecomposed into two layers by using adaptive directional lifting basedon wavelet transform. The angle of prediction is divided into nine parts.
Secondly, through the lifting wavelet transform the 2-D image signal
can be decomposed into low-frequency part and the high-frequency
part at different scales. The weight of the low frequency coefficientsis increased and the weight of the high frequency coefficients isdecreased. Low light level image enhancement can be achieved. Lastly,
wavelet coefficients after enhancement are fused at various scales.
The edge extraction is completed by determining the local modular
maximum of the fusion wavelet coefficients. This method can make thetarget edge information more prominent and suppress the backgroundnoise in the low light level target image.
The optical experiment results show that the optical correlation
recognition based on lifting wavelet transform can recognize low lightlevel target effectively and raise the low light level target recognition
ratio.

8559-23, Poster Session

Distorted target recognition based on Cannydifferential operator combined with MACH
filterJiyang Shang, Yu Zhang, Qibo Zhang, Wensheng Wang,
Changchun Univ. of Science and Technology (China)
The image pattern recognition, as a fast and accurate method of targets
identification and location, not only be used as target identificationand location means of industrial robots and production line automation
control in industrial production, but also can be used as missile terminal
guidance in the military area. Therefore, image pattern recognition
gets more and more people’s attentions. But up to now, image patternrecognition is still unable to accurately recognize the distorted targets(the targets rotated in plane or scale changed), which has restricted
the development of the image pattern recognition. In order to solve
the problem of inaccurate recognition for distorted target in cluttered
background among the image pattern recognition, the Canny differential
operator is used to optimize the Maximum Average Correlation Height(MACH) algorithm. The distorted (scale and rotation etc) target images
and the training images are edge extracted by Canny operator. The
training images are used to synthesize MACH filter. The low frequency
information of the distorted target images and the filter is enhanced by
Canny edge extracted. Then the MACH filter is used to filter the edge
extracted distorted target image. Thereby, the distortion tolerance ofthe MACH filter is expanded. By this method, which the edge extraction
combines with frequency domain filtering, the influence of the distortion
for the image pattern recognition is eliminated. In order to prove thefeasibility of this distortion target recognition method and determine
the distortion tolerance, a lot of computer simulation experiments havebeen made with the Canny differential operator and MACH filter. As an
example, in the recognition range, the arbitrary three rotation planes
and scale plane are selected to be tested. The experimental results
show that the position of the detected target and the position of its
output correlation peak have an explicit corresponding relationship. By
this way, the scale distortion tolerance is 0.84~1.56 times; the rotation
distortion tolerance can reach up to 80 degrees. For the targets ofexceeding the distortion tolerance range, the intensity of correlation
peak becomes weaker and weaker, but some of the targets can still beidentified.

8559-24, Poster Session

Multi-limit unsymmetrical MLIBD image
restoration algorithm
Yang Yang, Information Engineering Univ. (China)
A novel multi-limit unsymmetrical iterative blind deconvolution (MLIBD)
algorithm was presented to enhance the performance of adaptive optics
image restoration.The algorithm enhances the reliability of iterative blind
deconvolution by introducing the bandwidth limit into the frequency
domain of point spread (PSF), and adopts the PSF dynamic support
region estimation to improve the convergence speed.The unsymmetricalfactor is automatically computed to advance its adaptivity.Image
deconvolution comparing experiments between Richardson-Lucy IBD
and MLIBD were done,and the result indicates that the iteration number
is reduced by 22.4% and the peak signal-to-noise ratio is improved by
10.18dB with MLIBD method.The performance of MLIBD algorithm isoutstanding in the images restoration the FK5-857 adaptive optics andthe double-star adaptive optics.

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Conference 8559:
Information Optics and Optical Data Storage II

8559-25, Poster Session

8559-28, Poster Session

Gain and phase dynamics in strained
quantum well semiconductor opticalamplifiers

Optical correlation tracking of low contrast
target based on wavelet thresholdsegmentation

Cui Qin, Xinliang Zhang, Wuhan National Lab. for
Optoelectronics (China)

Su Zhang, Youjian Wang, Qibo Zhang, Wensheng Wang,
Changchun Univ. of Science and Technology (China)

gain and phase dynamic characteristics in the compressive, unstrained
and tensile strained quantum well (QW) semiconductor opticalamplifiers (SOAs) are theoretically investigated via a detailed model. The
traveling wave rate equation model includes ultrafast effects due to thecarrier heating and the spectral hole burning. The carrier heating effectcan be described by coupling carrier temperature equation to carrier
and photon density equations. Based on the calculation of energy band
structure, the effects of compressive and tensile strain on the differential
gain and the derivative of refractive index change are investigated.
The peak of the differential gain spectrum shifts to shorter wavelength
in the tensile strained structure. In the SOA operation wavelength
region, the value of the derivative of refractive index change is obvious
enhanced in the compressive strained structure. The characteristics ofthe differential gain and the derivative of refractive index change havesignificant influence on the gain and phase recovery dynamics in QW
SOAs. The different strained QW SOAs are examined with pump-probe
technique via simulation. By comparing the gain and phase recovery
dynamics in three different types of SOA samples, it is demonstrated
that the compressive QW SOA shows the fastest gain recovery rate andthe largest phase change. In addition, the ultrafast recovery process
due to the carrier heating effect can be enhanced significantly in thetensile QW SOA. The study can provide reasonable guidance forthorough understanding and proper design of QW SOAs, which areused in all-optical signal processing based on cross gain modulationand cross phase modulation.

Target tracking has a wide application in varieties of domains andhas a rapid development at home and abroad, so the research on
target tracking is more valuable in recent years. In this paper hybrid
optoelectronic joint transform correlator (HOJTC) is implemented for
tracking the target, which is considered as one of the most effective
methods.

8559-26, Poster Session

A GRIN medium coupler and its applicationin light beam spot conversion
Ning Wang, Fangkui Sun, Harbin Institute of Technology (China);
Lixue Chen, Harbin Insttitute of Technology (China); Lequn Li,
Harbin Institute of Technology (China)
GRIN (Gradient refractive index ) medium with a lateral sech refractive
index variation, can make normal-incident light beam gradually curveto the medium with a larger refractive index, and periodically converge
the light beam to a point smoothly and continuously. This property of
GRIN medium can be used as a coupler to realize a mode spot size
conversion. This paper mainly discuss the transmission property ofGaussion light beam in a sech GRIN medium by numerical simulation.
There are three situations for the variation of the half-width of theGaussion beam waist, including periodic convergence, collimationtransmission with a constant incident waist half-width and periodic
divergence. SOI waveguide is widely used in the photonic integrated
circuit, but coupling problem between an optical fiber and the submicrometer waveguide is still a challenge to be solved in a practical
optical communication system. To achieve a high coupling efficiency
between single mode optical fiber and single mode SOI slab waveguide,
which suffer a great light beam coupling loss for the mismatch of the
spot size. The GRIN medium coupling structures are designed as acoupler, with symmetric refractive index distribution and asymmetricrefractive index distribution. The single mode optical fiber has a modefield diameter of 10µm, and the symmetric slab SOI waveguide has acore thickness of 0.25µm. The insertion loss calculated in theory are
1.35dB and 1.56dB respectively, which has a significant improvement incoupling loss, compared with the 30dB coupling loss caused by directbutt-joint transmission.

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But in practical application, the low contrast character of the target andthe moving distortion problems between the target and the template
may cause the phenomenon of low recognition ratio of HOJTC. In orderto solve this problem, a kind of wavelet-based threshold segmentation
method is applied to increase the contrast. Through this algorithm thehistogram of the image is firstly decomposed into wavelet coefficientsat every scale with wavelet basis function Sym4. And then according
to segmentation norm and wavelet coefficients, the thresholds can bechosen from the approximate histogram. Finally use these thresholds
to segment the image into ideal areas. In addition, for the moving
distortion problem, taking temporal state of the target as the template
can realize the template update.
To prove this method, many tracking experiments of low contrast
targets have been performed with optical correlation method. As an
example a low contrast target “tank” (the gray contrast is less than2%) is presented. The tracking result shows that the brightness ofthe correlation peaks is enhanced and the target recognition ratio isincreased. The conclusion can be drawn that applying this algorithm
in optical correlation method can implement the low contrast target
tracking successfully and this algorithm provides an available solution
to low contrast target tracking.

8559-29, Poster Session

Optical isolator based on surface plasmon
polaritons
Wanyuan Liu, Fangkui Sun, Lixue Chen, Bowen Li, Harbin
Institute of Technology (China)
Optical isolator is a necessary passive optical element in modern
optical communication system. The common optical isolator is basedon Faraday rotation and it has been become a mature technology. The
size of the common optical isolator is about several centimeters, which
is not suitable for the optical integrated circuit. The Surface Plasmon
Polaritons(SPP) is caused by the oscillation of electrons and its wave
propagates at the interface of a metal and a dielectric. SPP is a slow
wave and its wavelength is about one tenth of the excitation light. For
this reason, it can be used in optical elements to solve the problem of
optical integrated circuit.
A new optical isolator mode which is based on the theory of SPP has
been designed. A dielectric waveguide and a SPP waveguide areformulated. And there is a gap in the middle of the core in the dielectric
waveguide. Low refractive index material is filled into the gap andthe total reflection is satisfied at the interface of the two materials.
Magneto-optic material is contained in the two waveguides and thetwo waveguides are stacked together. For the phase matching of thetwo waveguides and the total reflection at the gap, the light couples
from the dielectric waveguides into the SPP waveguides. With the helpof the SPP, the light passes the gap successfully and couples into thedielectric waveguide again. However, there is a different situation at thereverse direction. For the effect of the magnetic field, the permittivity ofmagneto-optic material has been changed and this caused the phasemismatching of the two waveguides. So effective coupling is not able
to finish between the two waveguides. With the total reflection at the

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gap of the core, the light cannot traverse the mode, and the aim thatreflected light should be isolated is achieved. The insertion loss value is
1.72dB when the light traverses through the optical isolator in forward
direction. In the reverse direction, the isolation value is 34.14dB. And
this result is better than the common magneto-optical isolator.

for Raman or SERS in the detection of low concentration greenhousegas (ambient CO2), biomedically significant molecules (e.g., glucose),and bacteria.

8559-30, Poster Session

Method for measuring retardation of infrared
wave-plate by modulated-polarized visible
lightAll-optical programmable logic arrays using
SOA-based canonical logic units
Lei Lei, Jianji Dong, Yu Yu, Xinliang Zhang, Wuhan National Lab.
for Optoelectronics (China)
All-optical programmable logic arrays (PLAs) based on canonicallogic units (CLUs), i.e., minterms and maxterms, are presented. We
experimentally demonstrated the full set of two-input and three-input
minterms as well as maxterms using the cross-gain modulation insemiconductor optical amplifiers (SOAs). Maxterms can be easily
obtained based on minterms. Correct and clear temporal waveforms
are achieved for all the canonical logic units. The measured extinction
ratios of two-input and three-input CLUs reach to ~ 15 dB and ~ 11
dB, respectively. Based on the CLUs, both sum-of-products (SOP) andproduct-of-sums (POS) formed PLAs are exhibited. Four important
logic functions, including multiplier, multiplexer, demultiplexer anddecoder, are presented as examples to show that the canonicallogic units-based programmable logic array (CLUs-PLA) can bereconfigured to perform different logic functions. Compared with thereported schemes, our proposal features several improvements andadvantages. (1) A programmable OR array is not required for SOPformed PLA since the products are canonical minterms, and arbitrary
combinational logic function can be demonstrated by adding the
canonical minterms directly. (2) The absolute and complementary
data patterns which are necessary for the PLA can be easily obtained
through the preprocessing. (3) The CLUs with different number of inputs
are achieved using the most efficient and simple nonlinear effect XGM
in SOA. (4) Maxterms can be easily obtained based on minterms, andthe reconfigurability and scalability of the system are largely enhanced
compared to our previous work. (5) Both SOP and POS formed CLUsPLA are proposed, and the simple structures composed of SOAs
and passive filters make them have a great potentiality to be largely
integrated.

8559-1, Session 1

Photonics crystal fiber Raman sensors(Invited Paper)
Claire Gu, Univ. of California, Santa Cruz (United States)
Hollow core photonic crystal fibers (HCPCF) employ a guiding
mechanism fundamentally different from that in conventional index
guiding fibers. In an HCPCF, periodic air channels in a glass matrix
acts as reflectors to confine light in an empty core. As a result, theinteraction between light and glass can be very small. Therefore,
HCPCFs have been used in applications that require extremely low nonlinearity, high breakdown threshold, and zero dispersion. However, theirapplications in optical sensing, especially in chemical and biologicalsensing, have only been extensively explored recently.
Besides their well-recognized optical properties the hollow cores of thefibers can be easily filled with liquid or gas, providing an ideal samplingmechanism in sensors. Recently, we have demonstrated that by fillingup a HCPCF with gas or liquid samples, it is possible to significantly
increase the sensitivity of the sensors in either regular Raman or surface
enhanced Raman scattering (SERS) applications. This is because theconfinement of both light and sample inside the hollow core enables
direct interaction between the propagating wave and the analyte, as
opposed to other types of fiber Raman/SERS probes that rely on theevanescent wave interaction with the analyte.
In this talk, we report our recent works on using HCPCFs as a platform

8559-3, Session 1

Ying Zhang, Beijing Univ. of Posts and Telecommunications(China) and Minzu Univ. of China (China); Feijun Song, China
Daheng Group, Inc. (China)
The wave-plates in the infrared spectral region are importantpolarized elements for modern optical communication technology,
astronomical observation field, etc. We propose a new method for
precisely measuring the optical phase retardation of infrared waveplates using modulated-polarized visible light. An instrument is set up
for measurement: collimated laser beam goes through a polarizer, anelectro-optic modulator, the wave-plate to be measured, a BabinetSoleil compensator, an analyzer, and finally incident upon the detector.
A sinusoid voltage with frequency f0 is applied to an electro-optic
modulator to produce a modulated-polarized light. A Babinet-Soleil
compensator is employed to make the phase delay compensation. A
photo-detector detects light passing an analyzer. A signal processor
selects only the fundamental frequency and the double frequency andshows the output signal on an oscilloscope. The zero and 2p positions
are identified when the oscilloscope shows a sinusoidal function withfrequency 2f0. The compensation from zero to 2p without wave-plateis called instrumental constant C(l). We measured several C(l) for
different l lasers and then produce a relation line. When the wave-plate
which need to be measured is put in the instruction, the zero occurs
when the compensator completely compensates for the wave-plate.
By simple calculating, we get the results of measuring the phaseretardation at 1064nm of a half wave-plate using 632.8nm and 532nm
laser. It is apparent that the measurement precision is less than andrepetitive precision is within 0.3%. The measurement precision of the
instruction is almost constant in the visible range.

8559-5, Session 2

Power flow study in subwavelength
plasmonic apertures and antennas (Invited
Paper)
Byoungho Lee, Il-Min Lee, Seung Yeol Lee, Seoul National Univ.
(Korea, Republic of)
Plasmonic subwavelength hot spot generation is an important issue
for data storage and sensing. The singular points of time-average
power flow in electromagnetic fields, which correspond to the saddle
or vortex of time-averaged Poynting vector fields, can be used as
qualitative parameters to understand the behavior of energy flowof electromagnetic systems. Near the presence of such singularpoint, the power flow lines show drastic change in their directions
and magnitudes, of which effect determines the characteristic of
the energy flow through the system. In general, such singular points
compose very complicated patterns near the edges of the metallic
structures but tend to converge to regular patterns when observed
far from the structural abruptions. As a result, in many subwavelength
plamonics systems such as plasmonic antennas or metallic slits, we
can find a rough relation between the power transmission efficiency
or field enhancement nature and the behavior of the singular points byobserving near the structural abruptions such as the slit or aperture
openings or the rod ends.
In this study, we investigate the relation between the singular points
in power flow in subwavelength plasmonic slit and antennas andother physical characteristics such as the field enhancement or power

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Conference 8559:
Information Optics and Optical Data Storage IItransmission efficiencies. The parameters we are interested in are
the relative locations of and the strength of the Poynting vector fields
near the singular points, especially around the geometric edges ofthe metallic structures. By investigating the power flows near isolatedor periodic slits and antennas, we hope to provide another view ofunderstanding the physics in those structures.

concept is integrated into the compact digital holoscope which provides
the system with the capability of measuring over a range of step heightsfrom the nanometer to the micrometer realm. Applications of the systemfor both transmission and reflecting geometries are discussed.

8559-6, Session 2

Dynamic resource-aware routing andfrequency slots allocation in SLICE using
adaptive modulation with consideration ofboth BER requirement and distance

The workpiece surface intelligent tracing
based on support vector machine in laser
remanufacturing
Nan Yang, Tianjin Univ. of Technology (China)
In laser remanufacturing, the laser beam need to point the normal
direction of the workpiece surface in order to keep constant radiation
area and constant energy density. This is a key point for forming
accuracy. However, the shapes of the workpieces are arbitrary, andit’s difficulty to obtain the normal vector directly according to the 3D
surface data of the workpiece which could be obtained by 3D laser
scanning system. So, the 3D data of the workpiece surface should beprocessed based on the nonlinear regression analysis firstly. Support
vector machine (SVM) is chosen for the nonlinear regression analysis,
because it has good capability and it could overcome “over-fitting”. The
normal vector could be caculated based on the kernel function usedin SVM. It’s rare to find the report that choosing SVM as a machinelearning method in laser remanufacturing process.

8559-7, Session 2

Light multinary computing: the evolution
from electronic binary computing
Jaime Arago, Freelance (Spain)
Next-generation optical communication and optical computing imply an
evolution from binary to multinary computing. Light multinary computing
encodes data using light components in higher orders than binary
and processes it using truth tables larger than Boolean ones. This
results in lesser encoded data that can be processed at faster speeds.
We use a general-purpose optical transistor as the building block todevelop the main computing units for counting, distributing, storing,and logically operating the arithmetic addition of two bytes of base-10
data. Currently available optical switching technologies can be used tophysically implement light multinary computing to achieve ultra-highspeed communication and computing.

8559-8, Session 3

Compact digital holoscope with dual
wavelength (Invited Paper)
Jianglei Di, Jianlin Zhao, Anand Krishna Asundi, Nanyang
Technological Univ. (Singapore)
Digital holography allows fast, nondestructive, full-field 3D
measurement of reflecting as well as transmitting objects. It is awell-established two-step method of digital recording and numericalreconstruction of the full complex field of wavefront. It has foundapplications in diverse fields, such as micro-optics and MEMS
metrology, cell imaging and particle characterization. However, forquantitative phase measurement there is 2? by phase ambiguities that
limit measurements of optical path lengths to the wavelength of theillumination light. For continuous profiles, phase unwrapping is used
to overcome the phase jumps. One approach is to use a synthetic
wavelength using two lasers with different wavelengths. This synthetic
wavelength would depend on the wavelengths of the two sources andthus can be tuned by selecting appropriate sources. In this paper, thisReturn to Contents

8559-9, Session 3

Lei Wang, Min Zhang, Beijing Univ. of Posts andTelecommunications (China)
Proposed in this paper is a dynamic resource-aware routing andfrequency slots allocation scheme with consideration of both BER
requirement and distance adaptive modulation (RA-BERR-DA) for
spectrum-sliced elastic optical path networks (SLICE).By dynamicallyconsidering the available frequency slots, the modulation complexityof a computed least crowded route can be adjusted.Physical topology
used in the experiment is a 7?7 mesh network with one server, 49
nodes and 84 dual links between nodes. We performed numericalsimulations using OMNET++ to compare the blocking rate and thefrequency slots occupation of RA-BERR-DA with those of DA. O-OFDM
adopted in this paper generates 8 subcarriers and the frequency slot
width is set as 12.5GHz. There are two basic modules in the simulation:
SERVER, which is in charge of computing route and deciding
modulation format; NODE, which is in charge of assigning resources.
Backward Reservation Protocol (BRP) in wavelength routed WDM
networks is used and the difference is that the reserved resources are
not wavelengths but slots. Four slots will be assigned if the modulation
format is QPSK and two slots for 16QAM. We apply first fit (FF)algorithm to choose slots. The dynamic connection requests follow as
the Poisson process and the source-destination node pair is generated
randomly from all the nodes. The holding time of each connection
follows a negative exponential distribution.

8559-10, Session 3

Dynamic wavelength, priority, and bandwidth
assignment (DWPBA) for long-reach hybrid
WDM/TDM-PON based on multi-threadscheduling
Yuqin Xie, Min Zhang, Beijing Univ. of Posts andTelecommunications (China)
Hybrid WDM/TDM-PON as a key solution is a smooth evolution of thepassive optical network to Next-Generation Passive Optical Networks(NG-PON). In order to combine the capacity of metro and accessnetworks, it is desirable to propose the Long-Reach (LR) PON, and the
propagation delay is proved to be the obstacle during the upstream
resource allocation.
In this paper, an enhanced multithread based on Multi-Point Control
Protocol (MPCP) was presented for the hybrid LR WDM/TDM-PON bytransmitting separate data messages and REPORT messages on the
different channels for upstream transmission along with broadcasting
the GATE messages on the single channel to the ONUs. Thisalgorithm exploits the benefits of having multiple processed runningsimultaneously as well as the joint scheduling and grant sizing methods
to improve the channel utilization, and reduce the packet delay. This
scheme is also to support the Quality of Service (QoS) requirements ofdifferent applications in typical access networks.
In the discription part of the algorithm,wo will give illustrative example
for scheduling method under joint scheduling and grant sizing,and
detailed algorithm process.This model is simulated under OMNeT++.
Then,the result analysis will be given.

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Simulated results is used to prove that the DWPBA outperforms the
traditional DBA in channel utilization and packet delay.

8559-11, Session 3

Holography display with LED illumination
based on phase-only spatial light modulator
Yan Zhao, Liangcai Cao, Qingsheng He, Guofan Jin, Tsinghua
Univ. (China)
A new holography display technology based on a phase-only spatial
light modulator (SLM) is proposed. The normal use of LD light source
led to the inevitable speckle noise introduced by the coherence of thelaser beam. Some algorithms and special diffractive optical elements
have been proposed to reduce the speckle noise. In this paper, aselected LED light source was used in the holography display system
to replace the LD light source. The temporal coherence and spatial
coherence of the LED were studied. Though the temporal coherenceof LED is short, the spatial coherence of the light field can be improvedby optimizing the optical paths such as decreasing the emitting area ofthe light source and so on. A high-power LED with a narrow band-width
was selected. An algorithm to generate computer-generated hologram
for the SLM based on partially coherent light was proposed. The
phase-only holograms for the display were computed using the partiallycoherent light algorithm. Then the phase holograms were uploaded
to the SLM. LED was used as the light source to illuminate the SLM
uniformly, and the reconstructions can be observed by naked eye. It
is demonstrated that LED is an accepted light source for holographic
display. The reconstruction results showed that the speckle noise andmultiple reflections were eliminated when LED was used as the lightsource.

8559-12, Session 4

Vector wave recording techniques for optical
data storage (Invited Paper)
Toyohiko Yatagai, Daisuke Barada, Utsunomiya Univ. (Japan);
Suganda Jutamulia, Univ. of Northern California (United States)
Optical recording techniques utilizing vector wave characteristics
potentially have high data transfer rate characteristics because avector wave has two complex amplitude components and they canbe temporarily and spatially modulated. In this paper, two types ofvector wave recording techniques are introduced. In these techniques,polarization-sensitive media are required. The one is dual-channel
polarization holography. In dual-channel polarization holography,
two superposed images can be simultaneously recorded. The two
images are transferred by two orthogonal polarization components ofa signal beam. The signal beam is superposed by a reference beam
and illuminated on a polarization-sensitive medium. Furthermore,
holographic multiplexing techniques can be applied. For optical data
storage, coded images are used. Two coded images are displayed on
two spatial light modulators (SLMs). The other is retardagrahy that is
a recording technique of retardation between orthogonal polarization
components. The retardation can be generated by using objects withretardance. In order to record a coded image, parallel-aligned liquidcrystal SLM (PAL-SLM) can be used. The PAL-SLM can modulate thephase of a linear polarization component with the azimuth parallel to theliquid crystal orientation axis. Retardagraphy can be regarded as a kindof inline polarization holography without beam splitting. The modulated
polarization component and another component are regarded as asignal beam and a reference beam, respectively. Therefore, holographic
multiplexing can be applied. In this study, it is confirmed that coded
images are recorded in multiple using these vector wave recording
techniques. From the results, these techniques can be expected for
optical data storage.

8559-13, Session 4

Novel holographic recording in
phenanthrenequinone-doped poly(methyl
methacrylate) photopolymer and its
applications (Invited Paper)
Shiuan Huei Lin, June Hua Lin, Ken Y. Hsu, National Chiao Tung
Univ. (Taiwan)
In this paper, we report our investigations on two novel holographic
recordings in phenanthrenequinone-doped poly(methyl methacrylate)
photopolymer, including polarization holographic recording andtwo-wavelength holographic recording. For polarization holographic
recording, we demonstrate that a polarization grating can be recordedin such material using two orthogonal polarization beams. The
best experimental results show that the diffraction efficiency of thehologram reaches to ~40 %, and the dynamic range of material (M#)
is 1.82 by using two orthogonal circularly polarized recording beams.
For two-wavelength holographic recording, we demonstrate that a
volume hologram can be recorded at 647-nm in a 2-mm thick sample
by use of a gating illumination at 325-nm. The experimental results
show that the diffraction efficiency of hologram reaches to ~30%,
suggesting as holographic medium with selective recording property.
Some applications on optical information storage using two recording
mechanisms will also be demonstrated.

8559-14, Session 4

Fundamental study on hybrid phase-coding
and spatial multiplexing for holographic data
storage
Wei Song, Shiquan Tao, Dayong Wang, Beijing Univ. ofTechnology (China)
In terms of noise suppression, orthogonal phase-coding multiplexing
has particular advantage. So the hybrid phase-coding and spatial
multiplexing (PCSM), which incorporates orthogonal phase-coding
multiplexing into spatial-multiplexing, has been considered recently.
In the preliminary research on PCSM, the position selectivity of phasecoded reference beam has been proved, but high quality storage ofhigh-resolution data pages has not yet demonstrated. The encodedreference beam contained many plane sub-beams, and the interference
between the phase-coded sub-beams was ignored in the analysis of
the early work. For implementation of high density and high quality data
storage with PCSM, a thorough study on the fundamentals of PCSM,
including the general principle and the optimized configuration, isnecessary.
In this paper, we investigate some fundamental aspects starting withnumerical calculation of the complex Fourier spectrum of an orthogonalphase coded reference beam. The results showed that there is acomplex and serious fluctuation in both intensity and phase distribution
if a Fourier transform configuration is used for reference beam.
Moreover, the phase is no longer binary (0 or &#61552;) but varying
continuously between -&#61552; and&#61472;&#61552;, this may
reduce the phase orthogonally and is not desired for PCSM. Also theadditional intensity distribution will influence the quality of the beam.
In order to maintain phase-only modulation and orthogonally in thereference beam pattern, we suggest that the phase modulator shouldbe imaged to the recording plane. Deeper researches on the principle
and configuration are still in progress.

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Conference 8559:
Information Optics and Optical Data Storage II

8559-15, Session 48559-16, Session 4

Experimental verification of hologram
generation using intensity images

Multiplexed holographic gratings recordedby 405nm laser in polymer film containing
spirooxazines

Ni Chen, Jiwoon Yeom, Keehoon Hong, Jae-Hyun Jung,
Byoungho Lee, Seoul National Univ. (Korea, Republic of)Digital holography is one of powerful methods for three-dimensional
displays. However, it generally needs a complicated interference
experimental setup which also induces some problems in the hologram
reconstruction, such as the DC term problem and the twin image
problem. We proposed a method for generating digital hologram fromthree diffracted intensity images. An object is illuminated by a plane
wave and three diffracted intensity images are captured by a charged
coupled device (CCD) along the wave propagation axis. By calculating
the amplitude and phase distribution from the intensity images using
the transport of intensity equation (TIE), we can obtain the wave front of
the object at the center intensity image plane, i.e., the Fresnel hologramof the object.
We already verified this method by numerical simulation. In this paper,
we do experiments to verify the proposed hologram generation method.
In the experiment we use simple setup with a laser and a CCD. The
captured images are used to calculate the hologram after some
preprocessing. The reconstruction verifies that the proposed method
works. We also compare the proposed method with conventional
digital holography that records the hologram by interferometry. Bothsimulation and experiments verify that the proposed method has no
twin image problem. Additionally, because the TIE works well underpartially coherent illumination, we also do an experiment that uses
partially coherent light source instead of laser to verify the partiallycoherent illumination requirement of the method. The partially coherent
light source enables the reduction in the hologram recording cost.
In summary, our proposed method is advanced in the recording
and reconstruction compared to the conventional method of digitalholography.

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Shencheng Fu, Changchun Univ. of Science and Technology(China); Shiyu Sun, Northeast Normal Univ. (China); Wenling
Sang, Bo Sun, Changchun Univ. of Science and Technology(China); Xintong Zhang, Yichun Liu, Northeast Normal Univ.
(China)In this rapidly evolving age of information, there has arisen the needfor high-density and rapid access memory system. To date, someinvestigations on photochromic spirooxazines have been carried out
in synthesis, reaction mechanism, optical switch and memory etc.
However, little attention has been the multiple holographic recordingby blue violet laser in spirooxazine doped polymer films, which will bepractically used for recording high-density hologram on the media in the
future. In this paper, the multiplexed holographic gratings were recorded
and probed in spirooxazine doped PMMA films by the blue-violet laser(405nm) and the He-Ne laser (632.8nm), respectively. Accompanied
by rotating the storage media, two sets of holographic gratings wererecorded at the same point in the sample. It was found that the growthrate of the holographic grating recorded later was lower than that of
the earlier one. To better understand the multiple holographic grating
formation mechanisms, the single holographic grating dynamics
was also recorded. The diffractive signal intensity increased sharply
and then decreased to a constant value. A theoretical description of
overlapped isomerization gratings agrees well with experimental results.
The obtained fitting parameters indicated that the decreased populationof spirooxazine molecules results in the longer response time and thelower contrast of the later recorded grating. Due to the long life of theisomerization gratings, the holographic interference fringes with theperiod of ~500nm were clearly observed by Confocal Laser Scanning
Microscope. By optimizing experimental condition, holographic gratings
with full angle multiplexing are supposed to be formed.

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NextConference 8560:
LED and Display Technologies II
Tuesday 6 –6 November 2012
Part of Proceedings of SPIE Vol. 8560 LED and Display Technologies II

8560-1, Session 1

Organic spintronics developed from organic
light-emitting diodes
Bin Hu, The Univ. of Tennessee (United States)
Inter-molecular excited states are essentially inter-molecular electronhole pairs with tunable electric and magnetic dipoles in organic
semiconducting materials. It has been experimentally observed thatinter-molecular excited states are sensitive to a low magnetic field(< 100 mT). We have found from magneto-capacitance studies thatinter-molecular excited states can exhibit an intrinsic coupling between
electric permittivity and magnetic permeability. The intrinsic coupling
between permittivity and permeability provides a promising mechanism
to realize excited states-based organic spintronics with magnetic
field-dependent optic, electronic, and optoelectronic functions byusing inter-molecular excited states. The magneto-electric studies haveindicated that inter-molecular excited states have mutually controllable
electric and magnetic dipoles. Therefore, electric and magnetic
polarizations can resonantly respond to an incident electromagnetic
field in a coherent manner. The photoinduced EPR measurements haveshown that inter-molecular excited states can magnetically change
electric polarization. The photoinduced permeability measurements
have indicated that inter-molecular exited states can electricallychange magnetic polarization. Furthermore, we have experimentallydemonstrated that using inter-molecular excited states forms a newmechanism to de-couple electrical and thermal conductivities, normally
un-available in natural materials, for the development of thermoelectric
devices. This presentation will present recent progress on intermolecular excited states-based organic spintronics.

8560-2, Session 1

Investigation of color-stable deep redemitting OLEDs and transparent LiF:Al
composite cathodes (Invited Paper)
Qu Bo, Peking Univ. (China); Chao Gao, Xi’an Modern
Chemistry Research Institute (China); Zhijian Chen, Lixin Xiao,
Qihuang Gong, Peking Univ. (China)
A novel soluble terpolymer (P8FO-Th-BT) containing 9,9-dioctylfluorene,
thiophene, and 2,1,3-benzothiadiazole units were synthesized by
Still coupling reaction. The single layer and multi-layer organic lightemitting diodes (OLEDs) based on P8FO-Th-BT was fabricated. A
deep red-emission device with the configuration of ITO/ poly(3,4ethylenedioxythiophene)-polystyrene sulfonate (PEDOT:PSS)/P8FOTh-BT:N,N’-Di(3-methylphenyl)-N,N’-diphenyl-(1,1’-biphenyl)-4,4diamine (TPD) (weight ratio being 1:1)/2,9-dimethyl-4,7-diphenyl-1,10phenanthroline (BCP, 15nm)/ tris(8-hydroxyquinoline) aluminum (Alq3,15nm)/ LiF(5Å)/Al(150nm) was obtained, and the maximum luminance
was measured to be 226 cd/m2 at the bias voltage of 10V. The
electroluminescent peak located at 708nm, and the spectrum covered
both the red and infrared regions. Moreover, the CIE chromaticity
coordinates of the device were inalterable when the bias voltage varied,
which was beneficial to the application on display.
The performance of OLEDs also depended on the electrical and opticalproperties of the electrodes. Therefore, a transparent and electricalconductive layer comprising LiF and Al was designed and obtained. The
composite layer was characterized using transparency spectroscopy
and sheet resistance measurement. When the ratio of LiF:Al reached
4:4, the sheet resistance and transmittance of the composite layer were573 W/q; and 55.5% (at 532nm), respectively. Transparent organic lightemitting diodes (TOLEDs) employing LiF:Al composite layer as cathodes
were fabricated and the electroluminescent properties of the TOLEDs
were investigated. When the composite cathode had the equal contentsof LiF and Al, the TOLED showed acceptable electroluminescentbehavior of both top and bottom emission and the total maximum
current efficiency (summed from both top and bottom emission) of the
TOLED was calculated to be 2.34 cd/A.

8560-3, Session 1

Optimal spectrum design of OLED indoor
lighting
Shih-Jie Dai, National Chung Cheng Univ. (Taiwan); HsiangChen Wang, National Chung Cheng Univ. (Taiwan) and National
Chung Cheng Univ. (Taiwan)
When the efficiency of OLEDs reached Fluorescent’s brightness level,
the OLED is becoming mature. With good surface characteristic oflight-emitting, low power and diversity of color distribution, OLEDs
has used on the panel backlight or special lighting. The study of white
OLED’s spectra for indoor lighting are rarely discussed. In this study,
we collected dozens of OLED’s spectra and recombined new spectrum
for indoor lighting. The images after new illuminant design can bedisplay by multi-spectral imaging technology. Finally, we discuss somemethods for specifying color-rendering properties of OLEDs such as
CRI, CQS, and FCI to prove the optimal spectrum of indoor lighting.

8560-4, Session 2

A simple, low-cost and portable LED-based
multi-wavelength light source for forensic
application
Wee Chuen Lee, Univ. Sains Malaysia (Malaysia); Bee Ee Khoo,
Universiti Sains Malaysia (Malaysia); Ahmad Famhi Lim bin
Abdullah, Univ. Sains Malaysia (Malaysia)
Forensic light sources (FLS) have been used frequently in crime scene
investigation as a scanning tool for crime scene evidence, such as
gunpowder residue, semen, bloodstain, saliva and urine. There wereseveral FLS reported in literature, such as Polilight®, Lumatec Superlite
400, PolirayTM, Bluemaxx BM500 and high intensity LED. LEDbased light sources are low in cost and flexible in design. Moreover,
LED technologies have been well developed recently, where several
types of wavelength LED can be used for light source design. Fromliterature, near UV light (300-400nm) and blue (450nm) light are usefulfor detecting semen, urine and saliva stains, while 415nm light is usefulfor bloodstains detection. In this paper, a simple, low cost and portableLED-based multi-wavelength light source for forensic application is
proposed. The proposed multi-wavelength light source is able to supply
near-UV, blue and 415nm lights from the same point of source anddirection, without utilizing any light guide, such as optical fiber. Each
type of LED array was mounted separately on the different surfacesof a holder. DC motor was used to rotate the holder for directing theselected LED array to face the object. The proposed design is low incost, easy to be manufactured, user-friendly and comparable to theother expensive FLS, such as Polilight® PL500 and Crime-lite®2, interms of detectable dilution of bloodstains.

8560-5, Session 2

Optimized LED spatial apodization andlocations for spatial uniformity in enclosed
space
Chung-Jen Ou, Chong -Jei Huang, Yu-Yuan Liu, Hsiuping
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Conference 8560:
LED and Display Technologies II
Institute of Technology (Taiwan)
Spatial uniformity and related photometric/radiometric quantities arevery important for optical engineering. Various optical programs had
been developed to deal with the calculation and analysis procedure.
Optimization and the cost effectiveness are the major difficulties tosolve complicated problems. In this paper, we demonstrate the level 1
approach to solve the specific spatial photometric distribution problems
by using the spreadsheet program. Base on the transient between thenear field area source and the far field point source approach, a reliable
illuminating spreadsheet is developed for LED and various kinds oflamp device. Since there is no ray tracing required, the algorithm is fastand simple.
The angular apodization of the LED or lamp can be determined andoptimized by simply using the spreadsheet program. Unpredicted
solutions are found in several arrangements, demonstrate thepossibilities and the effectiveness of the present method. Discussion on
the colour mixing and the scattering model of the LED/lamp device isalso provided.

terms of the optimization requirement on illumination and uniformity.
To insure the reliability of the simulated system, we will apply TracePro
optical package and its macros into our Genetic Algorithms to let
all optical elements become the real entities of evolution programs.
Furthermore, to consider the feasibility of evolution programs, it isnecessary to divide a medium or large scale of Backlight Module into
several small divisions to reduce the number of evolved groove angles.
However, how many sets of irregular linear Fresnel lenses are necessaryand how to design them will be complicated and technical.

8560-8, Session 3

First principles calculations of electronic
and optical properties of Zn1-x(TM)xO(TM=Mg,Cd)
Peng Chen, South China Normal Univ. (China)
The paper present study of the electronic and optical properties of

8560-6, Session 2

High efficient tandem blue fluorescentorganic light-emitting diodes based on C60/
NPB:MoO3 interconnecting layer
W T Bi, M X Wu, Y L Hua, Tianjin University of Technology(China)Tandem OLEDs(device A) is the same as single-unit device(deviceB), in which p-bis(p-N, N-diphenyl-amino-styryl) benzene(DSA-ph)
was used as blue emitting layer and 1,3,5-tri(phenyl-2-benzimidazole)benzene(Bphen) was used as ETL. Our experiment results indicatethat the luminance of the tandem device is basically equal to that of
the single-unit device, but the current density of the tandem device ismuch less than that of the single-unit device under a same luminance. A
excellent interconnection layer to effectively charge transport of tandem
OLEDs is generally very important. If C60 and NPB:MoO3 contacted
each other, a common Fermi level throughout both layers is requiredby equilibrium. Therefore, under the external electric field, the electrons
may tunnel through from occupied HOMO level of NPB:MoO3 tounoccupied LUMO level of C60. Then these electrons will immediately
be driven away from the interface by the external electric field andinjected into EML. In summary, the current efficiency of device B attains
33.8 cd/A at current density of 72.9 mA/cm2, which is almost 2.5 times
higher than that of the single-unit device A (13.5 cd/A) measured atcurrent density of 68.9 mA/cm2. This result indicates that LiF/Ca/C60/
NPB:MoO3/MoO3 functioned as an effective TIL.

8560-7, Session 3

Embed an irregular linear Fresnel lens intoa simple empty chamber to let a medium orlarge edge lighting LED backlight module bethin, lightweight, low-cost, and possess higheffect of light rays guiding
Wen-Gong Chen, Yung Ta Institute of Technology & Commerce(Taiwan)
We propose a new and effective Light Guide Plate, called Empty
Chamber Fresnel Lens Light Guide Plate (ECFL-LGP), for a medium orlarge scale Backlight Module. It consists of a simple Empty Chamberand several sets of irregular linear Fresnel lenses. Due to the reasonsthat the structure of the Empty Chamber is simple and a Fresnel lens isthin and cheap, our ECFL-LGP will own lower cost than the traditional
LGP. On the other side, the irregular Fresnel lens in our ECFL-LGP
will work better than the traditional LGP about the effect of light rays
guiding because its irregular linear groove angles can be evolved in

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Zn1-x(TM)x (TM=Mg,Cd), through density function theory (DFT) basedon first-principles method. The calculation indicate that the band gapof Zn1-xCdxO narrows as result of the increasing concentrations of Cd.
The paper shows that the Zn 4s and Cd 5s electron states broadens
to low energy states and that the O2p electron states broadens to highenergy states with increasing Cd-doping concentrations. The paper
advances a possible theoretical mechanism of Cd-doped regulating
Bands gap. Optical property of Zn1-x(TM)x (TM=Mg,Cd) is presented in
the paper.

8560-9, Session 3

Improvement of light extraction efficiency ofGaN-based flip-chip light-emitting diodes by
double-side patterned sapphire
Xiaoqing Du, Guangming Zhong, Weimin Chen, Xiaohua Lei,
Xianming Liu, Chongqing Univ. (China)
The flip-chip light-emitting diodes (LEDs) are very suitable for highpower and high brightness applications due to the effective heatdissipation. In flip-chip LED sapphire not only acts as substrate for
GaN layer growing, but also as light exit surface. Since the refractiveof sapphire (n=1.67) is obviously more than air, the total reflection at
the light exit interface would happen, which seriously reduces the light
output and light extraction efficiency (LEE) of LEDs. Light-exit surface
texturing has been the most effective and simplest one to improve LEE.
To make the surface structure controllable, a regular pattern should be
preferred. Furthermore, double-side pattern should be more effective
than single-side pattern in improvement of LEE.
In this work, we propose a double-side patterned sapphire structure toenhance LEE of flip-chip LEDs. Using Monte Carlo simulation method,
the impacts of sapphire substrate thickness, single-side pattern,
double-side pattern, pattern shapes and sizes on LEE were analyzed.
The simulated results show that compared to no-patterned and singleside patterned LEDs, double-side patterned LEDs have highest output
at the same chip size and sapphire thickness. By optimizing the sizeand shape of pattern pixel the LEE for double-side pattern could reachat more than 50%.
Using silicon oxide as mask membrane, double-side patterned sapphire
were processed by the standard lithography and reaction-ion-etching(RIE) technology. The LEDs with patterned sapphire were packaged.
The optical and electrical characteristics of the fabricated LEDs will
also be discussed. The measured light outputs of LEDs verified our
predicted effects.

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8560-11, Session 38560-13, Poster Session

Design and fabrication of a controllable haze
diffuser film

BaAl2S4:Eu thin films sputtered by complex
target with spark plasma sintering BaS:Eu
pellets

Zongbao Fang, Heng Zhang, Xiaohong Zhou, Linsen Chen,
Soochow Univ. (China)
Plastic diffuser films have been widely used in various applications
with LCD devices such as notebooks, TVs, monitors, and lighting
systems, etc., for beam shaping, brightness homogenizing, and lightscattering. For different applications, the properties of the diffuser
films will be chosen according to the realized functions, such as thetransmittance, the haze, and the divergent angle etc. In general, thediffusers can be classified into two types: the particle-diffusing typediffuser and the surface-relief type. As the mainstream product, thefirst relies on the transparent beads inside the plastic films or plates
to scatter light, which has not realized the special function such as
customized transmittance and haze etc. The second relies on the
microstructures on the surface of the plastic films or plates to scatter
light, which can be designed according to the customized requirements
by optical simulation software. However, the present fabrication
process is difficult to realize it under low cost condition. In this paper,
we will show a complete process including design and fabrication fora customized diffuser film with different haze and transmittance. The
micro-sphere structure will be utilized in the design process, and therelationship between the optical properties and the structure parameterand its distribution will be investigated. The roll to roll UV curing
process will be used for fabrication the diffuser film based on PET
material. The molding for UV curing is the nickel sheet with thousandsof microstructures fabricated by laser etching process. Finally, theuniformity and optical properties of diffuser films will be tested bysurface profiler, and haze meter.

8560-12, Poster Session

TDDFT investigation and design for
fluorescent molecules with push-pull
structures
Lin Tao, Beijing Jiaotong Univ. (China)
The electronic and geometrical structures of the ground and excitedstates of six fluorescent emitters, namely 3-(dicyanomethylene)-5,5dimethyl-1-(3-[9-(2-ethyl-hexyl)-carbazol]-vinyl) cyclohexene (DCDHCC),DCDHCC2, 3-(dicyanomethylene)-5,5-dimethyl-1(4-diphenylaminostyryl) cyclohexene (DCDPC), DCDPC2, 3-(dicyanomethylene)5,5-dimethyl-1-(4-[9-carbazol]-styryl)cyclohexene (DCDCC), and3-(dicyanomethylene)-5,5-dimethyl-1-(4-dimethylamino-styryl)
cyclohexene (DCDDC) which were specifically designed for organic
light-emitting diodes (OLEDs), were studied using density functional
theory (DFT) and time-dependent DFT (TDDFT) in conjunction withpolarizable continuum models (PCMs). Five hybrid functionals, PBE0,
M06, BMK, M062X, and CAM-B3LYP, were used and compared.
Theexperimental spectra of the molecules in acetone solvent wereprecisely reproduced with the BMK functional. The ionization potential
and the electron affinity were calculated to access the properties of themolecules in charge injection. It was found that, when double π-bridges
and acceptors were used, the emission of emitters red-shifted to the
optimal emitting region. Two brand new molecules, DCDCC2 and
DCDDC2, which are the double-branched counterparts of DCDCC and
DCDDC, respectively, have been designed. The calculated properties of
DCDCC2 and DCDDC2 in spectra and charge injection suggested thatthey would be as effective in their capacities as fluorescent emitters as
the above six emitters.

Dongpu Zhang, Beijing Institute of Technology (China) andBeijing Space Technology Development and Testing Ctr. (China);
Wei Xue, Zhinong Yu, Beijing Institute of Technology (China)
Europium doping barium thioaluminates thin films are sputtered by
Al complex target embedded with BaS:Eu pellets sintered by spark
plasma sintering (SPS). Thin films are deposited by RF-sputteringwith complex target. BaAl2S4 is found in each thin film sample while
BaAl4S7 appears in the samples only if the amount of BaS:Eu pellets
is more than 3. Oxidizing products are BaAl2O4, BaSO4 and Al2O3.
The amounts of barium thioaluminates including BaAl2S4 and BaAl4S7
will increase while the one of Al2O3 and BaS decrease if more BaS:Eu
pellets are embedded in the target during sputtering. Elements analysis
is carried out by EDS. The Al/Ba ratio in thin films will approach 2.0 withmore pellets existing in target. PL spectra of thin films are measured
and analyzed. The most obvious emission peak in each spectrum
is located at about 470nm which corresponds to the 4f65d1?4f7
transition of Eu2+ in BaAl2S4 lattice. The emission peak will approach
470nm as more pellets are embedded in complex target. As a result,it can be concluded that increasing the amounts of BaS:Eu pellets incomplex target is an efficient way to achieve better Eu doping barium
thioaluminates thin film.

8560-15, Poster Session

A semi-analytical approach for LED
secondary lens design
Chung-Jen Ou, Hsiuping Univ. of Science and Technology(Taiwan)Based on the geometric optics, the author proposed an analytical
approach for LED secondary lens design. The starting point for thesecondary lens is the base profile (first surface) near the LED die, where
the entrance angle of the LED ray can be calculate according to thegiven profile. Later, the complicated profile is generated according
to the required exit angle of the ray on the second surface, which
complete a mathematical mapping relationship between the spatial
apodization of the LED die to the angular apodization to both the nearfield and the far field terms. In this report, the author demonstrates the
profiles in the analytical form with iterative and non-iterative form. The
numerical solutions for the two forms are compared to the required
spatial apodization pattern, and the issues of the advantage andlimitations of this novel method is provided. Most important of all, thepresent method can combine with the analytical description of the LED
electrodes, such that improved the performance of the optimization
process and solved part of the non-uniformity problems.

8560-16, Poster Session

Energy transfer under applied electric field in
doped PLED by transient spectra
Lingchuan Meng, Yanbing Hou, Longfeng Lu, Beijing Jiaotong
Univ. (China)
We report enhanced Föster energy transfer from phosphorescentiridium(III )bis(4‘, 6‘ -diﬂuorophenylpyridinato)tetrakis( 1-pyrazolyl)
borate (Fir6) to fluorescent tetraphenylnapthacene (rubrene) in dual
doped PVK:Fir6:rubrene(100:10:0.3 in wt.) thin film under a increased
electric field, the PL lifetime of Fir6 decreased from 708ns to 557ns atapplied voltage from 0V to 20 V and according intensity of transient
spectra declined from 8.8 to7 in arbitrary unit. The electroluminescent(EL) spetra with different electric field of device of ITO/PEDOT:PSS(30155A  
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Conference 8560:
LED and Display Technologies IInm)/ PVK:Fir6:rubrene(100:10:0.3 in wt.)/ 2,9-dimethyl-4,7-diphenyl1,10-phenanthroline (BCP) (10 nm)/tris(8-hydroxyquinoline)aluminum(Alq3) (20 nm)/LiF (1 nm)/Al was given. The intensity of Fir6 wasdecreasing meanwhile that of rubrene was increasing as the applied
voltage increasing, that also indicate the enhanced Föster energy
transfer from Fir6 to rubrene . The mechanism for the enhanced Föster
energy transfer was discussed from energy level. The LUMO of Fir6
and rubrene have a litter difference, so the enhanced Föster energy
transfer was considered from reduced energy gap of HOMO of Fir6 andrubrene. Technique method, PL transient measurement was obtained byexcited the device with 5ns laser pulse wavelength at 355nm meanwhile
applying a revers ac voltage pulse on device and then coupling theemission through a filter into monochromator which connect to a
PMT(photomultiplier tube), at last the signal in PMT was extracted into aoscilloscope. The ac voltage source was connected with laser trigger by
a time delay to synchronize ac voltage output with laser pulse. We use
the ac voltage pulse but dc voltage to prevent the device breakdown athigh voltage.

8560-17, Poster Session

A new uniform chromaticity diagram basedon CIE1931 (x, y)Yusheng Lian, Ningfang Liao, Beijing Institute of Technology(China); Xiuze Wang, Institute of Science, Information
Engineering University of PLA (China); Jing Liang, School ofLight Industry and Chemical Engineering, Dalian Polytechnic
University (China); Jiajia Wang, Beijing Institute of Technology(China)With the rapid development of the new display techniques includingcolor LED display and laser display, the color fidelity reproduction
techniques for cross-media and color display quality of the newdisplay technology become more and more important. The uniform
color space is the key of color fidelity reproduction and new display
technology. In these early uniform color spaces, the uniformity oflightness is quite well, but the performance of the chromaticity has
not won great satisfaction. Therefore the establishment of a genuine
uniform chromaticity diagram is actually still an important work forboth the basic research in color science and the application of the newcolor display technology. In this paper, according to the properties anddistribution of Macadam ellipses on the CIE1931 (x, y), a new uniform
chromaticity diagram named (U, C) obtained by using the coordinatetranslation and non-linear compression along radius direction withthe aid of the iterative algorithm. Compared with CIE 1931 (x, y), theuniformity of (U, C) is obviously improved. Moreover, it appears to
perform as well as or better than these chromaticity diagrams in the IPT
and CIECAM02-UCS color spaces.

8560-18, Poster Session

TEM sample preparation andcharacterization of the group-III nitrides:
common problems and solutions
Xiao-Dong Yang, Xiamen Univ. (China)
The breakthroughs in material growth technology and device
technology of group-III nitrides, and the emergence of light emitting
diodes have advanced the semiconductor solid state lighting. As an
important characterization technique for the micro-nano semiconductormaterials, transmission electron microscopy (TEM) has been widely
employed to analyze the surface morphology, microstructures,
crystalline quality and other crystal characteristics of the group-III
nitrides. It also can make qualitative analysis of elemental composition.
However, stringent requirements for the TEM sample preparation,
especially for the hard and fragile semiconductor materials, and thediscrimination of image data validity are still critical problems. In thisarticle, some common problems and the solution methods for the
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TEM microstructure characterization and EDX analysis are raised andaddressed in detail.

8560-19, Poster Session

Effect of the projection lens on speckle
contrast measurement in laser projection
displays
Mei-Fang Xu, Wenhong Gao, Yunbo Shi, Pengfei Zhao, Jun Liu,
North Univ. of China (China); Xuyuan Chen, Vestfold University
College (Norway) and North Univ. of China (China)
Laser speckle is an important concern, as it degrades image quality.
Typically, one or multiple speckle reduction techniques are employedin laser displays to reduce speckle contrast. Likewise, speckle contrast
issues need to be carefully evaluated in designing laser displays under
different usage scenarios. In this paper, a laser projection display
system that uses moving small diffuser for speckle reduction is set up.
We demonstrate the effect of the resolution cell of the projector lenson speckle contrast measurement under the scenarios of free-space,imaging with different projector-detector geometry configurations.
The result shows that suppression of subjective speckle is much moredifficult than that of objective speckle. The former depends on theratio of the resolution cell size of the detector and the projection optic
at the screen, while the later is sensitive to illumination variation due
to its good transfer from the illumination to the screen. Low speckle
projection system based on those mechanisms realized the speckle
reduction from 36.59% to 2.75% by removing the projector lens.

8560-20, Poster Session

Quantum efficiency measurement ofluminescence glasses for white LED
Xiangkun Dong, Xiaoqing Du, Yulong Liu, Linjiao Ren, Lei Jin,
Xiaohua Lei, Weimin Chen, Chongqing Univ. (China)
Compared with the traditional light source, white LEDs play animportant role in lighting area with its advantages in energy-efficient,environmental protection, small volume, longer lifetime and soon. Luminescence glasses as an important part of white LEDs,
its luminescent properties affect the LEDs’ luminous flux, color
coordinate and so on, therefor it is necessary to study and measure
the luminescent glasses’ properties. The quantum efficiency is a major
parameter of luminescent materials which can characterize the skill
strength of excitation energy converted to luminous energy. Accurate
measurement of the quantum efficiency can evaluate the luminescent
properties of the luminescent glasses, which provides an importantbasis for quality improvement of the luminescent material.
Luminescence glasses have transparent and anisotropic characteristics,
for this reason, we adopted an integrating sphere with 20cm diameter
which was connected to a CCD Spectrometer to measure and calibrate
the fluorescence spectra of the sample. We designed and built thequantum efficiency measurement system. The system included four key
parts, which were the selection of test light source, the design of theintegrating sphere, the design of sample special fixture and the choiceof the grating spectrometer. Various components play different key rolein the measurement of quantum efficiency. We investigated the systemin the design and selection of various components parts, discussed theprinciple of measurement and put forward the calculation method.
Using the test system to measure YAG aluminum magnesium
fluorescent ceramic glass and compared with the literature values.
By measuring, the quantum efficiency for YAG fluorescent glass
was calculated to be 31% based on the absolute spectral power
distribution, it was coincided with the literature. And finally, we analyzed
the system error.

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LED and Display Technologies II

8560-21, Poster Session

The thermal effect of PLEDs by Raman
spectraZhe Qin, Jian Wang, Ya jun Chen, Civil Aviation Univ. of China(China); Cun zhou Zhang, Nankai University (China)
Raman spectra and infrared imaging systems are used for the study ofinternal temperatures of PLEDs. The aim is to measure the temperatureand investigate the thermal degradation of PLEDs with different current
densities. Raman intensity is proportional to the number of molecules in
the next higher vibration energy level, and accurate internal temperatureof PLEDs at thermal equilibrium can be calculated with the ratio of
anti-stokes to stokes Raman intensity by Boltzmann equation. With
the current density of PLED going from 0 mA/cm2 to 169 mA/cm2, it
is found that the internal temperature of PLED increases accordingly.
When the temperature comes to the glass transition temperature(Tg) of the emission layer, there is a phase change in it and the layer
becomes free state as liquid, which is not stable. Local disfigurementin the emission layer results in short circuit between the cathode andthe anode of a PLED, and the luminescence of PLED fails. At the sametime, we also use the infrarated imaging camera and thermal resistanceto detect the surface temperature of PLED. As a results, with the current
density grows, the temperature differences between the emission layerand surface become bigger. Therefore, Raman spectra is considered asa good method for detecting temperatures of thin-film semiconductor
devices.

8560-22, Poster Session

Design of freeform LED lens with large lightdeflection angle for road lighting application
Shaoyun Yin, Xiuhui Sun, Chongqing Institute of Green andIntelligent Technology (China); Yiming Pan, Liangping Xia,
Institute of Optics and Electronics (China); Jinglei Du, Sichuan
Univ. (China); qiling deng, Institute of Optics and Electronics(China); Chunlei Du, Chongqing Institute of Green and Intelligent
Technology (China)
LED owes the virtues of high efficacy, small size, better color rendering,
long life and environmental friendliness, and it is considered as the
fourth generation of lighting source. However, the radiation distributionof LED devices is usually Lambertian type, and they cannot be useddirectly in many applications. The ray deflection angle of the free-form
surface lens, which is the mainstream of secondary optical elements forvarious applications, is seriously restricted due to the Fresnel reflection
loss. In this paper, a method for designing freeform lens associated witha tilting aspheric is presented to achieve large deflection angle. Using
this design method, a Cree-xp-e LED road lighting lens for length L=
30m, road width W=12m, tilt angle &#61553;= 15 ° is designed andmanufactured. The experimental results show that the overall roadsurface luminance uniformity is as high as 0.7 and the glare factor isless than 2%. This design method greatly expands the light deflection
capacity of the traditional free-form surface LED lens, and it also
can be widely used in the design of LED road lighting lens and otherillumination applications where large light deflection angle is needed.

8560-23, Poster Session

diodes (LEDs) on air void embedded SiO2 mask. Firstly, a 30 nmthick GaN nucleation layer and 2 nm-thick unintentionally doped
GaN layer were grown on the c-face sapphire substrates by using a
metalorganic chemical vapour deposition (MOCVD) system. A normal
lithography, metal evaporation, and lift-off process were used tofabricate the SiO2 mask and silver (Ag) embedded SiO2 mask. Then,the conventional InGaN MQW blue LED structures were grown on the
different substrates under identical growth conditions. It is well shownthat the Ag was volatilized in the high temperature MOCVD growth
process and that was formed air void by the energy dispersive X-ray
spectroscopy images was carried out in scanning transmission electron
microscopy (STEM) mode. The light output power (at 20mA) of the LED
using epitaxial lateral overgrowth on the SiO2 mask and LED with the
air void embedded SiO2 mask are enhanced compared with that of theconventional LED. Furthermore, LED with the the air void embedded
SiO2 were shown the notable increase than the LED with the SiO2. The
enhancement of the LED with the air void embedded SiO2 mask could
be explained by the increment of light scattering and improvement of
quantum efficiency by reducing the dislocation.

8560-24, Poster Session

Preparation and characterization of Eu3+
ion in Mg-substituted tricalcium phosphate
phosphors
Tsung-Yuan Chang, National Taiwan Ocean University, Keelung(Taiwan); Hsiu-Mei Lin, Tai-Yuan Lin, National Taiwan Ocean
Univ. (Taiwan)
Photoluminescence investigation of Eu activated Mg-substituted
tricalcium phosphate (b-TCMP) phosphors were prepared by solid-state
reaction. The structure and emission spectra were well characterizedby X-ray diffraction (XRD) and photoluminescence (PL) techniques. PL
excitation spectra of b-TCMP:Eu3+ phosphors shows the excitation
peaks ranging from 350 to 400 nm due to 4f 4f transitions of Eu3+ions. PL emission spectra of Eu3+ ion under 394 nm excitation showsPL emission peaks at 593 nm (orange-yellow) due to 5D0 7F1transitions and 612 nm (red) due to 5D0 7F2 transitions. The excitationand emission spectra show that all the Eu3+ doped b-TCMP samples
can effectively emit the light excited by UV light. The red-emittingb-TCMP:Eu3+ phosphors may be efficient photoluminescent materials
for solid-state lighting phosphors.

8560-25, Poster Session

The variation laws of mutual coherencefunction in laser projector with moving
diffuser for speckle reduction
Gaoming Li, Yishen Qiu, Hui Li, Fujian Normal Univ. (China)
The variation laws of mutual coherence function in laser projector withmoving diffuser for speckle reduction are studied based on the partly
coherent theory. We take the magnification of lens and its spreadfunction into consideration, it gives us a method to weigh the speckle
reduction and the loss of optical energy while using the moving diffuser
for speckle reduction, and it points out the selection of diffuser slice forlaser display.

Epitaxial lateral overgrowth on the air voidembedded SiO2 mask for InGaN lightemitting diodes
Sang-Mook Kim, Korea Photonics Technology Institute (Korea,
Republic of)
We fabricated InxGa1–xN multiple quantum well (MQW) light-emitting

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Conference 8561:
Advanced Sensor Systems and Applications V
Monday - Tuesday 5 –6 November 2012
Part of Proceedings of SPIE Vol. 8561 Advanced Sensor Systems and Applications V

8561-1, Session 1

8561-3, Session 1

Laser spectroscopy applied to environmental
and medical research

An experimental study on detection of load
application onto an optical fiber by means ofchanges of a speckle patternSune Svanberg, Lund Univ. (Sweden) and South China Normal
Univ. (China)
Applied laser-based diagnostic methods as developed and pursued at
the Atomic Physics Division, Lund University, are illustrated. The fields
of application range from environmental monitoring including cultural
heritage assessment to biomedical applications. General aspects oflaser-based methods are non-intrusiveness, high spectral and spatial
resolution, and data production in real-time. Different applications are
frequently generically very similar irrespective of the particular context,
which, however, decides the spatial and temporal scales as well as thesize of the optics employed. Thus, volcanic plume mapping by lidar andoptical mammography are two manifestations of the same principle, as
is fluorescence imaging of a human bronchus using an endoscope andthe scanning of a cathedral using a fluorescence lidar system. Recent
applications include remote lidar-based monitoring of insect and bird
migration, and gas monitoring in scattering media (GASMAS). The
latter technique was employed as a new diagnostic tool for studying
materials including ceramics, but also for diagnostics of human sinus
cavities and new-born babies, as well as for assessing the integrity offood packages.

8561-2, Session 1

Thermal stability solutions for optical current
sensor using thermoelectric method (Invited
Paper)
Shuping Wang, Univ. of North Texas (United States); Xiaoling
Yang, Beijing Union Univ. (China); Abdullaziz Alahmari, Univ. ofNorth Texas (United States)
Compared to conventional current transformers (CTs) optical current
sensors (OCSs) have many advantages including electrical isolation,
zero hysteresis, large bandwidth, and light weight. Temperature stability
is one of the major obstacles that prevent the application of OCSs
to power industry. Specifically, the Verdet constant of the opticalmaterial used in an OCS based-on the Faraday effect is a functionof temperature. Therefore the rotation of polarization of the light
passing through the optical material in the OCS, which measures themagnetic field induced by the current under test, will be affected by
the temperature variations. In this paper a simple yet effective method
using thermoelectric effect and software to compensate temperaturedrift of an OCS based-on the Faraday effect is demonstrated. The
temperature of the optical material is constantly monitored by a selfexcited thermoelectric component. The resolution of 1°C and accuracyof ±0.3°C in temperature range from -40 to 80°C can be achieved. With
the accurate temperature information the Verdet constant of the opticalmaterial can be achieved by looking up a table of temperature vs.
Verdet constant that is experimentally obtained and stored in a memory.
The magnetic flux density (thus the current under test) with temperaturecorrection can then be calculated. An OCS based-on Faraday effect has
been fabricated and tested. The results from the OCS with temperaturecompensation are compared with those without compensation. Hightemperature stability has been achieved.

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Makoto Hasegawa, Muneki Kawahara, Chitose Institute of
Science and Technology (Japan)
In order to investigate possibility of utilizing speckle patterns to beobserved in an output light spot from an optical fiber due to external
disturbance for sensing application, a certain load was applied onto
an optical fiber through which laser beams emitted from a laser diodewere propagating, and changes in speckle patterns in the output lightspot from the optical fiber were observed. The obtained results showedthat when load was applied onto the optical fiber via a flat plate placed
over the fiber, no significant changes were recognized in the speckle
pattern. However, in the case where the optical fiber was placed sothat corrugated bending of the fiber was induced via load application
caused by ridges formed on the flat plate, the number of speckles in
the pattern decreased upon load application of certain degrees onto
the optical fiber. By employing other structures with ridges of difference
configurations and dimensions provided so that a contact area between
the ridges and the optical fiber was changed, certain influences wereconfirmed. Specifically, the larger the contact area between the ridges
and the optical fiber was, the more significantly the number of speckles
in the pattern decreased upon load application. From these results,
there is a possibility of utilizing changes to be observed in speckle
patterns formed in an output light spot from an optical fiber for sensingof load application onto the optical fiber by employing configuration inwhich ridges of appropriate dimensions are disposed against the opticalfiber.

8561-4, Session 1

Rotation phenomena of speckle patterns
observed in an output light spot from an
optical fiber and its applicability for sensing
application
Makoto Hasegawa, Yusuke Takahashi, Muneki Kawahara,
Chitose Institute of Science and Technology (Japan)
When coherent light beams, i.e., laser beams are incident on one endof an optical fiber, transmitted to another end to exit from there so as toform an output light spot on a screen, non-uniform intensity distribution
called speckle patterns is often recognized in the output light spot.
The authors have confirmed that when a multimode optical bare fiberis placed in a loop onto a support plate, the speckle patterns in the
output light spot appear to rotate while rotating the support plate. In
this paper, even when an optical fiber was placed in a U-shape, insteadof a loop, onto the support plate, the similar rotation of speckle pattern
was observed. Furthermore, it was confirmed that a distance between
the optical fiber placed in parallel at the edge of the support plate
provides certain influences on the observed rotating characteristics ofthe speckle patterns. Thus, the pattern rotation seems to be caused by
upward and downward displacements of the optical fiber at the edge ofthe support plate. In addition, even in the case where a jacket-covered
and connector-attached optical fiber was placed in the U-shape on the
support plate and a laser diode was employed as a light source, similar
speckle pattern rotation was recognized. Such rotation phenomenaof speckle patterns were observed with satisfactory repeatability, andtherefore, there is a possibility of employing these phenomena forsensing purpose.

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8561-5, Session 1

Rock mass acoustic emission detection
using DFB fiber lasers
Wenzhu Huang, Institute of Semiconductors (China) andShijiazhuang Tiedao Univ. (China); Huaixiang Ma, Shijiazhuang
Tiedao University (China); Wentao Zhang, Fang Li, Institute of
Semiconductors (China); Yanliang Du, Shijiazhuang Tiedao Univ.
(China)A systematic study of rock mass acoustic emission detection using
distributed feedback (DFB) fiber grating lasers is presented. In
this, the dynamic strain sensitivity of the DFB fiber grating laser indifferent coupled modes is calibrated by a comparasion method.
The ultra-narrow line width of the DFB fiber grating laser will result ina low equivalent noise level when using a fiber optic interferometricdemodulation. A minimum detectable strain of 10-12@900 Hz isachieved in the experiment. Furthermore, the acoustic emission
directional characteristics of the DFB fiber grating laser are investigatedby two kinds of analyzing method. In the first experiment, therelationship between the wavelength drift and the angle of a continuous
acoustic emission source is determined. In the second experiment,
the relationship between the percentage of wavelet packet energy andthe angle of impact response is established. Their acoustic emission
directional characteristics make them suitable for determining principal
strains and the direction of propagation of acoustic waves. Finally, three
DFB fiber grating lasers are used in the array and the acoustic waves
is detected, which shows that the fiber laser array is suitable to use foracoustic emission source location. Because of these advantages, suchas anti-electromagnetic interference, high sensitivity, small physicalsize, the ability to multiplexed and directional characteristics, the DFB
fiber grating lasers will provide a pracical and advanced measurementmeans in large civil structural health monitoring.

differential-and-cross-multiplying (DCM) and the arctangent approaches
are adopted. The digital PGC demodulation performance parameterslike wavelength resolution, total harmonic distribution (THD), signal tonoise and distortion (SINAD) and linearity is given.
Four-element DFB fiber laser hydrophone array system performance istested and its noise equivalent pressure (NEP) is below sea state zero(SS0).

8561-7, Session 2

Double clad fibers for opticalendomicroscopy applications (Invited Paper)Ming-Jun Li, Corning Incorporated (United States)
Nonlinear optical endoscopes utilizing two-photon process haveemerged as one of the best non-invasive means of fluorescencemicroscopy for early stage disease diagnosis. Compared with thesingle-photon microcopy, the two-photon microscopy offers inherent
optical sectioning property, a great penetration depth and flexible
optical spectra accessibility.
One of the key components for nonlinear microscopy is optical fiber.
Although a standard single mode fiber can be used to deliver a laser
beam to the target, it is not suitable for collecting the signals back due
to the low numerical aperture and small core size. To increase the lightcollection efficiency, a double clad fiber structure has been proposed.
Key requirements for double clad fibers include single mode core forpump light delivery, high numerical aperture inner cladding for signal
collection efficiency and low background noise.

8561-6, Session 1

In this paper, we present double clad fibers that are suitable
for nonlinear microscopy applications. We will discuss design
considerations and process for making double clad fibers. We
have made double clad fibers that are designed for the pump laser
wavelengths at 800, 1060, 1310 and 1550 nm. We will present
actual fiber results and examples for two-photon endomicroscopy
applications.

High performance four-element DFB fiber
laser hydrophone array system

8561-8, Session 2

Zhihui Sun, Li Min, Shandong Academy of Sciences (China);
Xiaolei Zhang, Shandong Univ. (China); Jiasheng Ni , Yingying
Wang, Jinyu Wang, Meng Wang, Chang Wang, Shandong
Academy of Sciences (China); Jun Chang, Shandong Univ.
(China); Gangding Peng, The Univ. of New South Wales(Australia)

Photonic crystal cavity Sensor integrated
with microfluidic channel in the visible region(Invited Paper)

A high performance four-element DFB fiber laser hydrophonearray system has been developed and tested. The system has theadvantages of low noise floor (<10^-6pm/ Hz^0.5@ 1 KHz) and wide
bandwidth (10Hz~10 KHz). The theory analysis, design, development
and test of the system are demonstrated in detail.

Photonic crystal(PhC)has been used to detect (bio) chemicalcomplexesdue to itsultrasmall sizeand the potentialto make the fullon-chip integration with sources and detectors,so-called lab on a chip.
Particularly, it can also operate as lasers to decrease the detectionlevel.In this work, we numerically study a two-dimensional(2D)
L3PhCnanocavity integrated with a microfluidic channel by using 3D
Finite Difference Time Domain(FDTD) method.The proposed L3structure
is a PhC slab with atriangular lattice on a GaN substrate, having alattice constant of a=235 nm, a slab thickness of 0.9a, a hole diameterof d=0.6a and a refractive index of n=2.45. The cavity is created by
missing three linearly aligned air holes (L3 type) with the first nearestneighbouring holes displaced by a distance of s=0.21ain the middle tomaximize the Q-factor.

The wavelength of four-element DFB fiber lasers is 1530.1nm,
1532.9nm, 1537.0nm and 1539.0nm respectively. The parameters ofeach fiber laser such as relative intensity noise, frequency noise andlinewidth are measured. Their influences on fiber laser hydrophone
performance are analyzed. Four DFB fiber lasers are multiplexed in asingle fiber, and then separated by a four channel DWDM with 200GHz
spacing.
DFB fiber laser hydrophone sensitivity enhancement and packing are
introduced. Acoustic pressure sensitivity is enhanced up to 115dB re
Hz/Pa. Frequency response is achieved with a fluctuation of ±4dB from
32Hz to1 kHz.
Interferometric interrogation method is adopted to realize highresolution fiber laser wavelength shift demodulation. Unbalanced
Michelson interferometer and digital phase-generated carrier (PGC)
demodulation are adopted. Michelson interferometer is well-built, andits performance such as fringe visibility, acoustic and vibration isolation
effect are tested. Two kinds of PGC demodulation algorithms such as

Lei Zhang, Tun Cao, Kai Rong Qin, Wei Ping Yan, Dalian Univ. ofTechnology (China)

Sensing is performed by measuring the wavelength shift of the PhC
cavity resonant peak due to the change of refractive-index distribution
inside and around the PhC caused by the introduction or the adsorptionof material. Since the change of resonant peakin thePhC is extremely
sharp, a high sensitivity is expected.We observethe resonant peak at
597nm for the structure with air overlaid. We then simulate the PhC
cavity with water (n=1.33) and two immersion oils (n=1.48 and n=1.518).
The minimal wavelength change Dl=5.2nm results in an index change
Dn=0.15.Wavelength shifts of 35nm/RIU for the structure.

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Conference 8561:
Advanced Sensor Systems and Applications V

8561-9, Session 2

A novel fiber optic microphone with threeflexural disks
Ran Tao, Anhui Univ. (China)
In this paper, we present a novel fiber optic flexural disk acoustic sensor
utilizing the resonance of flexural disks to get a high sensitivity at thewanted frequency range. Three flexural disks of different resonancefrequencies are used as sensing elements, and the pressure indued
strain in the flexural disks bonded with optical fiber is detected by theMach-Zehnder interferometer.

8561-10, Session 2

Single-helix chiral long period fiber gratings
for wavelength-interrogated liquid levelsensing
Li Yang, Yunfei Wu, Univ. of Science and Technology of China(China)Single-helix Chiral Long Period Fiber Grating (S-CLPG) has the similar
wavelength-selectivity to conventional Long Period Fiber Grating(LPG). It is fabricated by twisting an eccentric-core single-mode fiberwith a twist pitch less than 1mm at the melting state, and is desiredfor sensing applications owing to its stability even in high radiation
environment where conventional LPG fabricated by photosensitiveeffect becomes instable. To get a thorough understanding of spectral
characteristics of S-CLPG in response to surroundings, we develop
coupled-mode formulism for multimode couplings among LP01
mode and LP1n modes in the structure, and do simulations on its
transmission spectra when it is partially immersed in a liquid withrefractive index lower than that of cladding. Simulation results indicatethat the attenuation dips corresponding to the multimode couplings in
the transmission spectrum would shift continuously and monotonicallyas liquid level changes. We can thus develop a liquid level sensor basedon wavelength interrogation, which is beneficial to avoid sensitivity
deterioration caused by power instability in power interrogation for mostconventional LPG-based liquid level sensing. Then we demonstrate asensitivity of about 20 nm wavelength shift in sensing alcohol level from0 to 13 mm. In addition, we identify that the sensitivity can be improved
with a thinner fiber cladding or when the refractive index of the sensing
liquid is closer to that of the cladding.

8561-11, Session 2

Self-phase modulation in a nonlinear singlemode fiber Fabry-Pérot cavity with highintensity pulsed laser injection
Haiyan Chen, Cong Chen, Lilin Chen, Yangtze Univ. (China)
Single-mode fiber Fabry-Perot(FP) cavity ring-down
spectroscopy(CRDS) has attracted attention due to its applications
in aerospace, military, petrochemical, transportation, building andstructural monitoring, chemical, and biomedical sectors. There aresome kind of cavity structure such as fiber FP interference, fiber
Bragg gratings, and a fiber loop. However, the methods above do notconsider the birefringence in a single-mode fiber and the difference ofthe ring-down time caused by the two polarization modes. Recently,
a modified CRDS method called cavity ring-down beat spectroscopy(CRDBS) was proposed to study the minute birefringence in a fiber andall-optical clock recovery. In our previous work, we did some researches
on CRDBS in a single-mode fiber FP cavity, and took a try to photonic
generation of microwave/millimeter-waves and pressure sensor.
However, we did not discuss the effect of fiber nonlinearity.
In this presentation, we propose a nonlinear single-mode fiber FP

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cavity, in which CRDS is researched theoretically, and the relationshipexpression between output electric field amplitude and nonlinear
phase shift is derived. Numerical results demonstrates that the output
performance of nonlinear single-mode fiber Fabry-Perot cavity includes
three phases: build-up, stability, and ring-down phase, output power isinversely proportional to the power in cavity, when the power in cavity islarger than 2W, the stable time for output signal with instability becomes
longer, but the effect of self-phase modulation on CRD time is ignoring.

8561-12, Session 2

Characterization of Mach-Zehnderinterferometer-based photonic crystal fiber
sensors
Amine Ben Salem, Ahmed Dhib, Rim Cherif, Mourad Zghal,
SUP’COM (Tunisia)
Recently, extensive researches in chemical and biochemical sensing
applications have been devoted to the development of evanescentfield-based optical fiber sensors. These sensors exploit the fractional
power propagating in the evanescent field in order to analyze thespecimen’s properties surrounding the waveguide. Sensors based on
Mach-Zehnder interferometers (MZI) offer great potential with theirphase sensitivity to the refractive index (RI) variation and allow thedevelopment of highly-sensitive robust sensors.
In this work, we propose a new design of MZI structure assembled with
two arms composed of 400nm-diameter-hole-modified silica photonic
crystal fibers (PCFs) and immersed in solvent solution. The proposed
design is found to enhance considerably the sensitivity. One PCF-arm
is used as reference and kept isolated from the specimen. The other
PCF-arm is considered as sensing arm exposed to the specimen with acertain sensitive-area-length. A highly-sensitive versatile interferometry
technique is used to determine the phase shift from both arms andconsequently the specimen’s information can be retrieved. The
proposed sensor was first tested when considering the specimen to beanalyzed with different concentrations for a probing light of 325nm. The
sensitivity of detecting the benzene solutions in water reaches 9 rad/µm which is much higher compared to what was achieved in photonic
nanowires [1,2]. Then, the detection of corn oil into olive oil is achieved
with high sensitivity of 14.7 rad/µm demonstrating that the sensor iscapable of detecting a RI variation of 4?10-7 in only 1-mm sensitivearea-length. Thus, the proposed MZI-based PCF-sensor shows to bevery attractive for compact, flexible and high sensitive biochemicalsensing.
[1] J. Lou, L. Tong, and Z. Ye, “Modeling of silica nanowires for opticalsensing,” Opt. Express 13, 2135-2140 (2005).
[2] P. H. Wu, C. H. Sui, and B. Q. Ye, “Modelling nanofiber MachZehnder interferometers for refractive index sensors,” J. Mod. Opt. 56,
2335-2339 (2009).

8561-13, Session 3

Phase shifted FBG fabricated with arc
discharge erasing technique (Invited Paper)
Yuanhong Yang, Xiaozhe Zhang, Xuejing Liu, BeiHang Univ.
(China)Phase Shift Fiber Bragg Gratings (PSFBGs) has unique transmission
spectrum which has a narrow transmission line in the normal stop band.
This characteristic has great potential for laser, sensing and filtering
application. There has been a huge effort in improving their fabrication
techniques. PSFBGs have been fabricated with a UV-writing technique
by using of a specially designed phase mask incorporating the required
phase shift, by translating the fiber or the phase mask when the writingbeam is scanned, by post processing uniform FBGs with UV postexposure and etching the fiber cladding.
In this work, a Arc Discharge Erasing (ADE) post processing technique

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was studied and taken to fabricated PSFBG. The FBG ADE effect wasdemonstrated experimental first and useful parameters was obtained.
Based this technology, the capability and fabrication technique wasinvestigated and the full control of the spectral characteristics of the
PSFBG, including the position, reflectivity and bandwidth of the phaseshift peak was demonstrated. To get optimum technique parameters,
many experimental fabrications were done and the characteristic
curves under different discharge electric current, times and position
were gotten and the effect of original FBG length and the annealing
processing were investigated experimentally. With this technique, thein-line erbium doped fiber PSFBG fabricating system was built and thesingle mode DFB fiber laser was achieved with line width less than 1
kHz.

8561-14, Session 3

A novel method for design and developmentof magnetic motor based on thermal energy
Nithin Goona, National Institute of Technology, Goa (India)
This paper presents the study on the variations in thermal andmagnetic properties of permanent magnets with temperature gradientfrom cryogenic to room temperature. The concept of adiabatic
demagnetization gives the basic idea on variation in temperature ofparamagnetic substances due to the application of magnetic field. The
present work is on the variations in magnetic fields due to change intemperatures of ferromagnetic substances, which is the reverse processof adiabatic demagnetization. Adiabatic demagnetization explainsconservation of energy, and this holds good everywhere, including
reverse process of adiabatic demagnetization. The study on thermal
conductivity of ferromagnetic material at cryogenic temperatures
gives the amount of thermal energy being transferred from or to thesurroundings and hence gives the variations in magnetic fields due
to temperature changes. The objective of this project is to obtaintemperature gradient of samarium cobalt permanent magnets fromroom temperature to cryogenic temperatures. The thermal conductivity
verses temperature curve gives necessary information about thermal
properties. The thermal properties of samarium cobalt rare earth
permanent magnet help in understanding the variations in its magnetic
fields. As samarium cobalt rare earth permanent magnet do quite well at
cryogenic temperatures, this study is much useful in future applicationsof permanent magnets at cryogenic temperatures. Numerous references
report the successful use of samarium cobalt to temperatures as low as
2 K.

8561-15, Session 3

Monitoring system for high steep slope
based on optical fiber sensing technology
Feng Li, Yanliang Du, Shijiazhuang Tiedao Univ. (China);
Wentao Zhang, Institute of Semiconductors (China); BaochenSun, Shijiazhuang Tiedao Univ. (China); Fang Li, Institute of
Semiconductors (China)
Landslide is typical geo-hazards which causes serious threat to thehuman lives and infrastructures. It’s meaningful to develop an early
warning system to avoid landslide disasters. In this paper, a realtime monitoring system, based on optical fiber sensing technology,
was designed to track the health status of slope. Through effective
encapsulation, optical fiber grating stress gauge, optical fiber grating
inclinometer and optical fiber grating anchor, corresponding surface
deformation monitoring, internal displacement monitoring and anchor
axial force monitoring respectively, were demonstrated. A light switch(1?4) was introduced to expand the demodulation equipment to 16
channels, which can meet the capacity of more than 200 FBGs. Basedon the driving circuit, different channels can be switched to complete
demodulation. Through the multiparameter monitoring network, remoteand real-time monitoring of the slope can be realized, providing a
reliable guarantee for the slope safety.

8561-16, Session 3

Fabrication and sensing characteristics oftilted long-period fiber gratings
Rui Wu, Yunqi Liu, Na Chen, Fufei Pang, Tingyun Wang,
Shanghai Univ. (China)
Tilted long period fiber gratings (TLPFGs) have attracted more and more
attention because their many novel properties, such as stimulating
the coupling between core fundamental and homonymous or reverse
direction high-order cladding modes, polarization character. We
demonstrated experimentally the fabrication of TLPFGs with different
tilt angles and period by CO2 laser. The experimental results revealthat the LPFGs written with different tilt angles have quite different
transmission spectra and the coupling coefficient of low-order cladding
modes is higher than that of high-order ones. The tilted refractive
index modulation enhances the coupling coefficient between thecore fundamental mode and cladding mode. We wrote the non-titled
LPFGs with equivalent grating pitches in the same single-mode fiber.
The experimental results of the comparison between the TLPFG
and corresponding equivalent LPFG show that the TLPFGs’ mode
coupling is almost same with the equivalent non-titled fiber gratings,
while the writing efficiency of the TLPFGs is much higher and the CO2
laser energy needed is much lower. We also tested refractive index
sensitivity of TLPFGs and the equivalent non-titled fiber gratings. The
experimental results indicated that tilted LPFGs has higher refractive
index sensitivity than the corresponding equivalent LPFGs. The TLPFG
could be widely used in optical communication and fiber sensors.

8561-17, Session 3

Highly sensitive temperature measurement
based on polymer-coated single-modemultimode-single-mode fiber structure
Linlin Xue, Yujuan Zhang, Di Che, Qijin Zhang, Li Yang, Univ. of
Science and Technology of China (China)
Recently, sensing applications of multimode interference in the
single-mode-multimode-single- mode (SMS) fiber structure has
attracted much attention. All-fiber sensors based on the structure own
the advantages of low cost and easy fabrication, in addition to thecommon advantages as an optical fiber sensor, such as immunity toelectromagnetic interference, resistibility to harsh environments andcompact size. A sensitivity of about 10pm/oC was demonstrated intemperature measurement, and it was enhanced to about 30pm/oC byusing a bent form. Here we present a novel way to greatly enhance thesensitivity by replacing the cladding of the silica multimode fiber witha polymer coating. The polymer we used is Poly (MMA-co -TFEMA),
whose thermo-optic coefficient is about 50 times higher than that ofsilica. In this paper, we first analyze the transmission characteristics ofthe polymer-coated SMS fiber structure by using the mode expansion
method, and present optimizations of design parameters such as thelength of multimode fiber and refractive index of the polymer. Then
we fabricate polymer-coated SMS fiber samples for experiments.
By monitoring wavelength shift of valleys in transmission spectrum
resulting from multimode interference, a measuring sensitivity of about
700pm/oC is obtained, 20 times higher than the reported highest one
based on the structure to the best of our knowledge. With the present
desirable coating technique, we believe that this simple structure is
promising in high sensitive temperature sensing and measurement.

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Conference 8561:
Advanced Sensor Systems and Applications V

8561-18, Session 3

8561-20, Session 4

Experimental investigation of birefringenceof solid core polarization maintaining
photonic crystal fibers

Optical voltage sensor using single Fresnelrhomb Bi4Ge3O12 crystal

Weiqian Duan, Yuanhong Yang, Xing Zhang, Miao Ye, BeiHang
Univ. (China)
Photonic Crystal Fiber (PCF) is a sort of micro structure fiber actually.
Many unique characteristics, such as endless single mode, small mode
field diameter and bend loss insensitive, etc. can be realized withspecial structure design. A solid core polarization maintaining PCF (PMPCF) was made by destroying the isotropy of the circular cross-section
and desired birefringence can be obtained with special parameters. This
PM PCF made of pure SiO2 material and theoretically analysis shown it
may have nearly temperature-independent birefringence which is very
important for many sensing application. In this paper, we characterized
the temperature and operation wavelength sensitivity of birefringenceof a commercial polarization maintaining photonic crystal fiber as a
typical case first. The temperature dependence of birefringence due
to two main factors, namely temperature-induced variations of therefractive index of the glass and the thermal expansion of the fiber intransvers directions, were investigated and simulated in detail. The
simulation result shown that the birefringence temperature susceptibility
can be described as a second-order polynomial of &#61516; (distance
between small holes) and zero sensitivity to temperature may beobtained at optimum structure parameters with desired operation
wavelength. The PM PCF structure parameters measurement setup
and the birefringence measurement setup were built. The structure andbirefringence of five PM PCFs were measured with different operation
wavelength under different temperature environment experimentally andthe relationship of different parameters was analyzed and some design
rules were summarized. The experimental result agrees with theory
analysis well and the nearly temperature-independent birefringence ofsolid core PM PCF can be realized with optimum structure parameterswith certain operation wavelength.

8561-19, Session 4

The fabrication of nanostructures CIGS thinfilm solar cell (Invited Paper)
Li-Hsi Chen, Xusn-Yu Yu, National Chung Cheng Univ. (Taiwan);
Hsiang-Chen Wang, National Chung Cheng Univ. (Taiwan) andNational Chung Cheng Univ. (Taiwan); Jian-Hung Lin, ChiaChen Hsu, Chien-Chao Tsiang, National Chung Cheng Univ.
(Taiwan)When the incident light meets the interface between air and electrodelayer, reflection occurs from difference of refractive indices. Reflectionmeans the loss of the light, which is absorbed to solar cell andgenerates electric power. In order to prevent the reflection, some kindof anti-reflection methods need to be developed. Surface anti-reflection
treatment can be categorized to 4 different techniques including surface
texturing, single-layer interference coating, multi-layer coating andmoth-eye structure forming. Among them, moth-eye effect, introducedby Bernhard, caused gradual change in refractive index by forming
nano-sized patterns on the surface. Thus the reflection of incident light
can be minimized over the whole spectra range. In this study, we usedlaser interference lithography technique to produce nanostructures on
Copper Indium Gallium Selenide solar cells. The CIGS solar cell is akind of thin film solar cell, and it has the best conversion efficiency of
the thin film solar cells. We fabricate 500nm of nanoholes on the CIGS
film and arrange in cubic structure and hexagonal structures. Finally, we
discuss the gaining degree of optical efficiency.

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Changsheng Li, BeiHang Univ. (China); Rong Zeng, Tsinghua
Univ. (China)
In conventional polarimetric voltage-sensing scheme, an additional
quarter wave plate generally is needed to provide a proper optical bias,
and it will induce extra measurement errors due to polarization axis
mismatch and temperature effect, etc. Among various used quarterwave-plates, the right angle prism-based wave-plate is distinguishedbecause its quarter wave phase retardation is produced by the total
inner reflection of the light wave passing through the prism. However,this prism-based wave plate still is a separate element from the voltage
sensing crystal, and there exists some issues related to light coupling
and reflection, etc.
In this paper, a novel optical voltage sensor is proposed that uses single
Fresnel Rhomb bismuth germanate (Bi4Ge3O12, BGO) crystal as bothvoltage sensing element and quarter wave plate. Therefore, the quarterwave optical phase bias is provided by the sensing crystal itself, any
additional quarter wave plate is not necessary for the proposed voltage
sensor that consists of one Fresnel Rhomb BGO crystal and two prism
polarizers. The voltage sensing principle is theoretically analyzed indetail, and its feasibility is demonstrated by related experiments. DC
voltage in the range of +-10V~+-2200V was measured and the standard
error of the linear fitting slope for experiment data was less than 4.9x106. AC voltage with 50Hz industrial frequency was also measured within
2000V, and related standard error was less than 1.8x10-5.

8561-21, Session 4

Sub-pixel algorithms on linear-array detector
grating spectrometer
Chuan Qin, Jianlin Zhao, Dexing Yang, Biqiang Jiang,Northwestern Polytechnical Univ. (China)
The optical signal interrogation techniques play an important role infiber Bragg grating (FBG) sensing areas. Unlike the traditional OSA,
which is unstable, low speed and bulk because of its mechanicalscanning parts, linear-array detector grating spectrometer draw more
attention recently. However, most of the array-detectors, especially,
those within the IR range have limited pixels which lead to poor
resolution. In this paper, the spectrum of Gauss apodized FBG isanalyzed by using transfer matrix method, and the basic principles of
sub-pixel curve fitting algorithms including mass center, Gauss andfull-width-at-half-maximum (FWHM) are discussed. Based on this,simulation and experimental results are given to compare the three
curve fitting algorithms. The results reveal that in simulation, masscenter fitting method with an accuracy of 13pm while in experiment,
FWHM fitting method with an accuracy of 23pm provides a better
match to the actual curve. The research achievements have been
applied on the prototype of linear-array detector grating spectrometerand have potential market in portable FBG interrogation field.

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Advanced Sensor Systems and Applications V

8561-22, Session 4

A geometric algorithm for space opticalimaging system based on topologicalmapping relationshipZhang Zhi, Zhou Feng, Ning-juan Ruan, Beijing Institute ofSpace Mechanics and Electricity (China)
Space imaging system is affected by micro-vibration of satellite
platform on orbit. Therefore, image quality is degraded by varianceof attitude angle. High resolution image is easily smeared by motion
error of satellite. However, it is very hard to find the error source on thespace environment accurately. According to studying geometry modelof space camera, the transform relationship between object plane
and image plane is put up. Firstly, the paper analyses attitude error
and motion source of TDI camera on orbit. Then, the transform matrix
is analyzed between earth coordinate and image plane coordinate.
The geometry model contains in-out orientation elements. Secondly,
imaging procedure of TDI space camera is simulated. Different modesof micro-vibration are added into imaging model in order to simulate
jitter on the image. Multi-mode micro-vibrations are simulated on theline of sigh at same time. And then the experiment simulation is basedon three axis. Imaging procedure of TDI space camera is simulated
based on physical character of imaging system. Different images are
simulated by changing number of TDI. Various motion errors of satellite
are comprised in geometry model. Hereafter, the geometry distortion of
pixel position is calculated on image plane. The measurement accuracyof geometry distortion is sub-pixel scale. Afterwards, the corresponding
simulated image will be generated if the motion parameters of space
imaging system are fixed. Finally, the boundary condition is analyzed.
Over passing this extent, image quality will be obviously degradedby changing error amount of motion. The result is good for analyzing
parameters of satellite platform and guiding design of remote sensor.

8561-23, Session 5

Planar optical microring resonators used as
biosensors: design of polymer compared to
semiconductor based waveguides (Invited
Paper)
Rene Landgraf, Fraunhofer-Institut für Photonische
Mikrosysteme (Germany) and Technische Univ. Dresden(Germany); Toni Haugwitz, Robert Kirchner, Andreas Finn,
Technische Univ. Dresden (Germany); Frank Deicke, FraunhoferInstitut für Photonische Mikrosysteme (Germany); Wolf-Joachim
Fischer, Technische Univ. Dresden (Germany) and FraunhoferInstitut für Photonische Mikrosysteme (Germany)
Due to their small footprint and high sensitivity to biological moleculebinding, planar optical microring resonators gained high interest for
use as optical biosensors. Typically, these microring resonators are
made of semiconductor based material and are manufactured bytime-consuming lithography and etching steps. Semiconductor based
waveguides have high refractive indices, and thus, a high refractive
index contrast between core and cladding. In this case, due to strong
mode confinement, substrate leakage is a comparably minor issue andbending loss becomes relevant only at small bending radii of less than
10 µm. The main loss is determined by surface scattering, and thus,
semiconductor based curved waveguides are designed to have verysmooth sidewalls.
If polymer materials are used, as in this work, microring resonators
can be cost-efficiently manufactured by nanoimprint lithography.
The resulting larger polymer waveguide diameters facilitate in- andout-coupling, and polymer surfaces allow using established surface
biofunctionalization techniques. For polymer waveguides, due to thesmall refractive index contrast, surface scattering loss is a minor issue,
but bending loss is dominant due to the low mode confinement. In thiswork, design guidelines for polymer microring resonator waveguides
are given and compared to semiconductor based waveguides. 3-D
FDTD simulation results, including coupling factors and ring waveguidelosses, are presented for various relevant waveguide cross-sections.
Results are compared with analytic calculations. The effects ofnanoimprint manufacturing will be discussed. First measurement results
are presented.

8561-24, Session 5

A sensitive refractive-index sensor with amicrostructure metamaterial
An Yang, Jiangsu Normal Univ. (China); Changchun Yan,
Jiangsu Normal Univ. (China) and Nanyang Technological Univ.
(Singapore)
we design a micro-structure metamaterial which has a good capabilityof the realization of sense of refractive indexes and is different fromother sense structure. The metamaterial consists of a large metallic
split ring and a metallic small one located on the surface of a substrate.
The two spilt rings have a common axis and surrounded by a specificmaterial. By simulating resonance behaviors of the structure with afinite element method, we find the resonance frequency as a functionof refractive index of the specific material, which is used as a refractiveindex sensor. We also studied the effect of the substrate thickness andthe aspect ratio of the spilt rings on the resonance. Analyzing all kindsof effect, we propose a set of optimized parameters which effectively
enhance the sensitivity of the sensor. An evident advantage of such asensor is that it can easily be integrated with the other elements due to
its miniaturization, which constitutes a complete functional device.

8561-25, Session 5

Sensitivity limits of guided modes in silicon
integrated waveguide-based sensors
Oleg Zero, Norwegian Univ. of Science and Technology(Norway); Astrid Aksnes, Norwegian Univ of Science andTechnology (Norway)
The material characteristics of silicon, and especially the high index
contrast offered by the silicon-on -insulator (SOI) platform offers
the potential for building sensors that are both sensitive, extremelycompact and compatible with the CMOS fabrication. Due to the highdegree of light confinement in silicon, a minute geometrical perturbation
can result in a considerable change to the effective refractive index of aguided mode, hence enabling a potential sensing mechanism. However,when analyzing the sensitivity limits of typical integrated photonic
components, such as microring resonators or integrated Mach-Zehnderinterferometers, the ultimate sensitivity of a sensing device is often
dictated and limited by the device’s overall surface area. In principle,
the existence of a set of multiple guided modes might, however, allow
improving the sensitivity without increasing the device’s size.
The aim for the study is to investigate the achievable sensitivity indifferent geometrical configurations related to traditional integrated
photonic components. Utilizing numerical modeling tools based on
finite elements method (e.g. COMSOL), the sensitivity limits of such astructure are investigated in terms of small geometrical changes andeffective index response. Furthermore, the possible enhancement tothe sensitivity that is related to simultaneous multiple mode coupling
is discussed and various geometries are analyzed by means of 2- and3-dimensional simulations and a representative structure based on(multi-) mode coupling is presented.

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Conference 8561:
Advanced Sensor Systems and Applications V

8561-26, Session 58561-31, Poster Session

Lidar observations of the urban aerosols:
case study on the air quality in China

Characteristics analysis of coating layer
power distribution of Eccentric Core Optical
Fiber

Zhenyi Chen, Anhui Institute of Optics and Fine Mechanics(China)Two measuring campaigns were performed in the downtown ofGuangzhou in South China and Shijiazhuang in North China in2010 and 2011 , to investigate the concentration and distribution ofurban aerosols . Polarized LIDAR (MPL) operating at 532 nm were
employed to track the spatial and temporal aerosol distributions. PM10
concentrations of particles and the wind profile lidar were continuously
monitored within the Lidar observing region. The results illustrates
that the aerosol types can be estimated based on the depolarization
ratio. And we found the aerosol concentrations within the lower
troposphere and found the daily aerosol cycles. In both Guangzhou andShijiazhuang measuring sites, we observed the cases with increased
aerosol concentration,associating with the presence of point sourcesof particulate matter. Furthermore, the back trajectories from hysplit arealso used to identify the pollution sources.

8561-28, Poster Session

A fiber-optic flexural disk microphone ofhigh sensitivity
Ran Tao, Ran Tao, Xuqiang Wu, Qifa Zhang, Sheng Huang,
Benli Yu, Anhui Univ. (China)
A fiber-optic flexural disk microphone is developed to detect acoustic
signals in the air. It consists of a Mach-Zehnder interferometer with an
optimized sensing arm of 7.93 m. The disk’s resonance frequencies
and their influence on the microphone’s sensitivity are investigated. The
microphone’s frequency response is measured in the frequency range
from 100 Hz to 5 kHz and the average phase sensitivity is about -120.7
dB re 1rad/?Pa.

8561-29, Poster Session

Simulation analysis and theoretical model ofelectro-optic modulator in Rayleigh BOTDA
Hu Wang, Yongqian LI, Huan Li, Qinger He, North China ElectricPower Univ. (China)
The system based on Rayleigh Brillouin optical time domain analysis
can work with the non-destructive way only by using one-laser, oneended and single fiber, modulating pulse base and pulse at the sametime by using electro-optical modulator (EOM) based on intensity is the
key technology for this system to obtain continuous light and pulsed
light. A new modulation method is analyzed theoretically and simulated
by using a pulse generator connected to the bias port of EOM and a
microwave signal connected to the RF port of the EOM to modulate
pulse base and pulse simultaneously. The best operating point problemof Rayleigh BOTDA system by using EOM is discussed, the continuous
light and pulsed light of Rayleigh BOTDA system are obtained bysimulation, the theoretical basis for the analysis and design of different
structures of stimulated Brillouin distributed sensing system is provided.

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Liu Jianxia, Harbin Engineering Univ. (China) and College ofElectronic & Information, Heilongjiang Institute of Science &Technology (China); Yuan Libo, Harbin Engineering Univ. (China)
Eccentric Core Optical Fiber belongs to a kind of special Optical fiber.
The centre axis of core does not coincide with clad. Because of thespecial physical structure more energy than the conventional fiber
exists in the form of evanescent wave field and will result in higher
sensitivity. The energy distribution will be influenced when the change ofthe coating refractive index. When the external environment causes thechange of the coating refractive index, it may be detected by observing
the output spot size of Eccentric Core Optical Fiber.
In practical many optical fibers are made up of poly-regions in each ofwhich the refractive indices are homogeneous. Since 1970 Clarricoats
etc presented firstly the matrix method to analyze the poly-regions fiber.
Suematsu etc have done much more research. However, the previous
research in the area is restricted to analyze characteristics of thepoly-regions circular optical fiber. In this paper, analyze characteristics
of double-cladding coating layer propagation properties of EccentricCore Optical Fiber. Firstly, base on the mode theory of the doublecladding step-type circular optical fiber and make use of the Conformal
Transformation to obtain propagation properties of Eccentric Core
Optical Fiber. Present the general characteristic equations according
to the Optical Network concept. Secondly, take Eccentric Core OpticalFiber for example, make use of above theory, numerical calculate toLP01 mode in different eccentric distance and excitation wavelength.
Offer ?~V characteristic curve in different conditions. Study the
relationship between the core-region energy distribution and eccentriccore distance, working wavelength and coating refraction index ofEccentric Core Optical Fiber. Finally, compare the energy distribution ofEccentric Core Optical Fiber and circular optical Fiber.
The above revolution will provide an important theoretical foundation to
the applications of Eccentric Core Optical Fiber.

8561-32, Poster Session

A method for improving Rayleigh-BOTDA
system performance
Yongqian Li, Hu Wang, Huan Li, Qinger He, North China ElectricPower Univ. (China)
In this paper we describe and implement a long-range Rayleigh
Brillouin optical time domain analysis (Rayleigh-BOTDA) system using
Simplex optical pulse coding techniques, for temperature or strain
measurement, in order to overcome the trade-off between the spatial
resolution and measurement accuracy and achieve a higher signalto-noise ratio (SNR). The composition method of Simplex coding is
discussed, the physical mechanism for Brillouin scattering process inthis system is analyzed and an approximate mathematical model ofRayleigh-BOTDA system based on transient coupled wave equationsof stimulated Brillouin scattering (SBS) is proposed. Based on theforegoing work, the theoretical analysis of Simplex coding applied toRayleigh-BOTDA system is presented, and the system performancesin time and frequency domain are simulated numerically by Matlab.
Simplex coding using 63 bit codeword provide up to 6 dB SNR
improvement, allowing for temperature or strain measurements with
1 m spatial resolution over 10 km of standard single-mode fiber. The
simulation results show that the method can improve both the SNR andmeasurement accuracy of the system without degrading the spatial
resolution.

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8561-33, Poster Session

8561-37, Poster Session

Research on fiber Bragg grating based on
nano-fiber

A structured light vision sensor fordiscrimination of failure laser radar datacaused by multiple reflections of laser beam

Nuan Jiang, Zhengtong Wei, Yongming Hu, National Univ. of
Defense Technology (China)
Fiber Bragg grating sensors have been attracted more attention due
to its excellent advantages, such as small size, light weight, low cost,
immunity to electromagnetic interference, multiplexing and so on,which offer a widely application in optical sensing and communication
field. Following the appearance of nano-fiber, it is imperative todevelop the manufactured technology of nano-fiber devices, nanofiber Bragg gratings are the important passive device among these.
In this paper, we present a new method to fabricate the nano-fiber
Bragg grating. In our theoretical analysis, effective refractive index ofnano-fiber is a significantly parameter affected by the diameter of fiber,
which determined the Bragg wavelength. A nano-fiber Bragg grating
was fabricated through successive improvement of manufactured
technology.

8561-35, Poster Session

Localized surface plasmon resonanceproperties of I-shape Ag/SiO2/Ag
nanoparticles
Juanyi Liu, Zhejiang Ocean Univ. (China); YuLiang Liu, Lili
Li, Yaner Feng, QiuLiang Zhao, School of ElectromechanicalEngineering of Zhejiang Ocean University (China)
The plasmon resonance of I-shape Ag/SiO2/Ag nanocube was studied
using finite difference time domain numerical calculations. The resultshows that I-shape nanocube exhibits higher extinction intensity due
to its more “hot sports” compared to single layered metal nanoparticle.
At the same time, a higher refractive index sensitivity which increases
about 100 nm/RIU for single nanoparticle and about 65 nm/RIU for
nanoparticles array respectively can be obtained. This structure holds agreat potential in the application of bio/chemical sensing.

8561-36, Poster Session

The frequency mixing impact analysis of
the light intensity noise with modulation
signals in phase generated carrier (PGC)
demodulation method
Jiaolong Yu, Jiaolong Yu, Anhui Univ. (China)
In order to improve the measurement resolution of laser Doppler
interferometer, the noise of the system need to suppress, which thelight intensity noise have a greater effect on the performance of theinterferometer. By analyzing the impact of the light intensity noise
inherent in the relaxation oscillation noise to the mixing signal of phase
generated carrier (PGC) demodulation, arrivaling at a conclusion that
the Low-frequency part of the light source intensity noise have a greater
impact on the signal to noise ratio of PGC demodulation, and thephase carrier modulation signal have achieved the noise spectrum of
the relocation. Optoelectronic negative feedback program is proposedto achieve effective suppression of the Low-frequency light source
intensity noise and laser relaxation oscillation peak, which reduce theinfluence of the mixing of the light source intensity noise, furthermore
the system signal to noise ratio (SNR) is improved.

Xiao Kang, Wei Zhu, Li Tian, KeJie Li, Beijing Institute ofTechnology (China)
Laser radar is widely used for obstacle detection. The emitted laser
beam from the laser radar is reflected by the obstacle; laser radar
receives the echo and processes the data by means of a time of flight
calculation to get the position and size information of the obstacle.
When obstacle is complex or the terrain is fluctuant, multiple reflectionsof laser beam often happen. Obstacle’s position and size information
obtained by the laser radar data in this situation are error. Hence
how to discriminate these failure laser radar data caused by multiple
reflections of laser beam is a key and difficult issue. A structured lightvision sensor is proposed for the failure laser radar data discrimination
which is composed of a point light source laser, fast piezoelectric
ceramics steering mirror and high sensitivity industrial camera. Spotsemitted by the laser are projected to the steering mirror and are formed
the line structured light through the fast mirror swing. The image ofthe light stripe distortion which caused by the obstacle is obtained by
the camera. Position and size information of the obstacle are obtained
through fast image processing. When multiple reflections of laser beam
happen, position and size information obtained by the structured lightvision sensor and laser radar are different significantly. The conflict andcontradiction of information is used for the discrimination of failure laser
radar data. Experiment results show that the sensor can discriminate
the failure laser radar data at the accuracy rate of 92%.

8561-38, Poster Session

A method for improving the performance ofBrillouin echo system
Yongqian Li, Huan Li, Hu Wang, Qinger He, North China ElectricPower Univ. (China)
The high spatial resolution can be achieved in the traditional Brillouinecho system. Generally, the upper sideband of the CW light iseliminated before it enters into the fiber in this system, only the lower
sideband interacts with the pulse light, but this system exists pumpdepletion, and the sensing length is limited. An improved method of
distributed optical fiber sensing based on Brillouin echo is studied inthis paper, a double sidebands signal of optical carrier suppressed(OCS) which includes the Stokes light and anti-Stokes light is producedby the modulation of the electro-optic modulator (EOM) with thetechnology of optical suppressed carrier modulation, and the Stokes
and anti-Stokes light interact with the pulse light respectively, andthe processes of Brillouin gain and loss occur simultaneously, as thepump light power is the dominate factor limiting the sensing length,
based on the improved configuration, the pump almost unchanged.
The distributed Brillouin signal are received by subtracting the twoside bands of the OSC Stokes light, and the transient coupled wave
equations of stimulated Brillouin scattering (SBS) are deduced by atime domain perturbation method, and the transient solution is also
obtained. The improved Brillouin echo system compared with thetraditional Brillouin echo system by Matlab simulation, the results
show that a higher signal-to-noise ratio has been obtained in the
improved sensing system, and the sensing distance of the system
can be increased effectively with improving the spatial resolution andmeasurement accuracy.

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Conference 8561:
Advanced Sensor Systems and Applications V

8561-39, Poster Session

Use of bending of a single SMS fiber
structure for measurement of temperaturesensing
Yujuan Zhang, Qijin Zhang, Univ. of Science and Technology ofChina (China)
A simple temperature sensor based on a bent single mode–multimode–
single mode (SMS) fiber structure fastened on polymer base plate is
proposed and experimentally investigated. The surrounding refractive
index (RI) is higher than that of the silica multimode fiber and the leaky
structure is formed. Thus RI changes with temperature will lead tochange of output intensity without wavelength shift. We set up a simple
experiment to demonstrate that change the curvature of proposed
SMS fiber structure will result in central wavelength shift. The proposed
SMS fiber structure is put into oven thermostats and utilizes changing
temperature to control the curvature of SMS fiber which is induced
by expanding of polymer base plate. The shifts of central wavelength
are measured at temperature range from 60 to 75 ºC. The proposed
temperature sensor offers sensitivity of 3.9 nm/°C, which is significantly
higher than that of a normal straight SMS structure (10 pm/°C) or a
grating-based fiber structure (FBGs:10 pm/°C, LPG:100 pm/°C).

8561-41, Poster Session

Ultra-long distance distributed fiber-optic
system for intrusion detection
Dongsheng Tu, Zhaogong Jiang, Ningbo Nuoke Electronic
Technology Development Co., Ltd. (China); Shangran Xie,
Tsinghua Univ. (China); Shangjin Ren, Ningbo Nuoke Electronic
Technology Development Co., Ltd. (China); Min Zhang,
Tsinghua Univ. (China)
This paper research an ultra long distance distributed fiber-optic
intrusion detects system based on bidirectional mach-zehnderinterferometer. The system has a narrow linewidth laser source
and a low noise photodiode amplify module at the each end of theinterferometer. The laser source is amplified by a high power EDFA, theninput into the mach-zehnder interferometer, and receive at the other endof the fiber. When an intrusion event is act on the fiber, the interference
signal is different from the background. The other two communication
fibers are used to transmit and receive the high speed synchronous
codes. When system detects an intrusion event, recording the codesof the two ends. By measuring the time difference of intrusion signal
caused by the event after high speed signal process, the location of
the event along the sensing fiber is determined. The challenges of thissystem are to reduce the nuisance alarm rate and enhance the locating
accuracy at ultra long distance. At the present experimental result,
system implement the sensing length up to 100km, and the locating
accuracy is one thousand of the full length.

8561-42, Poster Session

Characteristics of in-fiber Mach-Zehnderinterferometer formed by lateral offset
splicing
Xiujuan Yu, Ge Li, Shengchun Liu, Jintao Zhang, Xuefeng Chen,
Liying Zhang, Heilongjiang Univ. (China); Yanbiao Liao, Tsinghua
Univ. (China)
We present an in-fiber Mach-Zehnder type interferometer (MZI) in
single mode fiber based on lateral offset splicing technique. The MZIrelies on the interference between the fundamental core mode anda co-propagating cladding mode. To build an in-fiber MZI, we need

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one element or device which excites two co-propagating modes
and another one to recombine them. In our case, the excitation
and recombination of modes is realized by two cascaded lateral
offset splicing joints. The effects of the lateral offset amount, theinterferometer cavity length, and the fusion splicing parameters on
the property and performance of the in-fiber MZI were investigatedexperimentally. By choosing an appropriate lateral offset amount, the
MZIs with good interference fringe contrast and low insertion loss canbe fabricated. Several in-fiber MZIs with different interferometer lengths
were built and it is found that the interference peak wavelength spacingis inversely proportional to the interferometer length L. The potential
applications of the proposed in-fiber MZI were further investigated as
temperature and strain sensors.

8561-43, Poster Session

Analysis on the performances of multiple
parameters measurement base on the
distributed optical fiber sensing system
Lei Qin, Wei Liu, Capital Normal Univ. (China)
With the rapid development of distributed optical fiber sensing
technology, it has become a hot research issue. Distributed opticalfiber sensors can simultaneously measure temperature and pressure
information along the fiber distribution, which is usually continuouschange in time and space. The distributed optical fiber sensing
technology based on Rayleigh scattering and Raman scattering studies
have tended to be mature, and gradually move toward practical.
The distributed optical fiber sensing technology based on Brillouinscattering has a later start, but because of its the higher measuring
accuracy, range and spatial resolution for temperature and strain
compared with those of the other sensor technology, it has been
extensive attention and research. In 2009, A. Wosniok and his partnerin Germany report on the development of a distributed optical fiber
monitoring system for strain and temperature detection along singlemode fibers, in which the sideband technology and digital filter are
adopted in order to lower the shift influence and increase the frequency
range.
In this letter, the distributed optical fiber sensing system based on
Brillouin scattering is built, while maintaining precision, and multiple
physical parameters are detected at the same time. The key technology
and method are used to improve the signal receiving and processing
capability.

8561-44, Poster Session

Distributed feedback fiber laser strain
sensor with high sensitivity in a wide
frequency range
Xiaolei Zhang, Shandong Academy of Sciences (China);
Gangding Peng, The Univ. of New South Wales (Australia);
Chang Wang, Zhihui Sun, Jiasheng Ni, Yingying Wang,
Shandong Academy of Sciences (China)
A compact high-sensitivity distributed feedback (DFB) fiber laser
strain sensor with length of only 56 mm is investigated. The intrinsic
performances including optical efficiency, intensity noise of bare DFB
fiber laser are tested before packaging. Theoretically the deformation inacoustic pressure field of DFB fiber laser with or without packaging canbe simulated by finite-element method. Based on the simulation resultsa polyurethane spindle-like structure is applied for fiber laser packaging.
By use of an imbalance Michelson interferometer and a standard
optical phase demodulator, the frequency response of DFB fiber laser
before and after packaging is tested in a vibration liquid sound field andcompared to standard PZT hydrophone. The experimental results showthat the prestress on bare fiber laser affects the frequency response
rather than strain sensitivity; the frequency sensitivity of packaged DFB

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fiber laser hydrophone is about 113dB•re•Hz•Pa-1 at 1 kHz, whichis 55 dB higher than bare fiber laser under the same prestress. It isremarkable that in a quite wide frequency range from 10 Hz to 10 kHz, it
has a rather flat frequency response with about 18dB fluctuation.

8561-45, Poster Session

Surface plasmon resonance sensor basedon grapefruit photonic crystal fiber filledwith silver nanowires
Zhang Lei, Shijiazhuang Univ. of Economics (China)
The Photonic crystal fiber (PCF) has attracted more attentions for its
flexible structure design and excellent optical performance, and it has
become a new focus in the fiber optical research domain, particularly
prominent in the research areas of fiber sensor. In recent years, manyscholars put forward photonic crystal fiber (PCF) based SPR sensors.
The sensing mechanism is though coupling the leaky core mode to theplasmon to achieve resonance sensing. The use of the photonic crystal
fiber, with its flexible design, makes it easy to equate the effective
index of the core mode to that of the material under test. Thus phasematching condition between the core mode and the plasmon can beeasily achieved at the required wavelength and then resonance occurs.
In this letter, surface plasmon resonance sensors based on grapefruittype photonic crystal fiber filled with silver nanowires have been
analyzed though the finite element method (FEM). The regularity of theresonant wavelength changing with refractive index of the sample has
been numerically simulated, and resonant wavelength detection as wellas intensity detection sensitivity has also been discussed. The surface
plasmon resonance sensing properties of PCF based on different
nanowires structures are numerically simulated; Numerical results showthat excellent sensing characteristics of the structure can be achieved
as the radius of the silver nanowires is 150nm, with both spectral andintensity sensitivity in the range of 4?10-5~5?10-5RIU.

8561-46, Poster Session

Discrete multi-target on-off states detection
and location with optical fiber sensing
systemNian Fang, Lutang Wang, Zhaoming Huang, Chen Liu, Shanghai
Univ. (China)
Multiple-target sensing is the development trend of the optical fiber
sensing technology. People hope to employ a single sensing system
to detect all targets needed. In many applications, alarms are usuallynecessary. In addition, some sensing systems are aimed to monitor
the state changes of the targets, for example, a door being opened orclosed. When multiple targets located at different places are required
for their state detections, a sensing system capable of detecting on-off
states of discrete multi-targets and their locations will be demanded.
We present such an optical fiber sensing system composed ofmultiple cascaded 1x2 fiber couplers (FCs). Each FC is connected toa reflective optical switch sensor (ROSS). It can remotely detect on-off
states of multiple ROSSs, as well as accurately and rapidly locate the
ROSSs in alarm states. By detecting the various intensities of pulsing
light reflected by each ROSS, their on-off states can be monitored.
The ROSSs in alarm states can be located by directly measuring thereflected light pulse intensity at corresponding time axis or the declined
peaks of short-time cross-correlation of reflection pulse train during
adjacent optical pulse period in noisy case. The simulation results withthe same and different ROSS intervals show that the detection andlocation methods proposed are feasible and effective. The discretely
distributed ROSSs optical fiber sensing system can be used to detectand locate various kinds of physical and chemical parameters at thesame time, which reflect state changes of the ROSSs. Although theproposed system is similar to the optical time domain reflectometry(OTDR), it has lower cost and better real time performance than OTDR.

8561-47, Poster Session

Camera calibration external parameters
amendments in vision measuring
Yexin Zhao, Naiguang Lv, Xiaoping Lou, Beijing Information
Science & Technology Univ. (China)
In the field of vision measuring, camera calibration is a necessary
precondition of the three-dimensional measurements.Especially,in binocular vision measurement system, the calibration
accuracy plays a vital role on the reconstruction of 3D objects
coordinates,therefore,camera calibration is researched.The
main content of the paper is that the system model of camera
calibration,principles as well as procedures in some traditional
calibration methods is discussed; in addition, the problem of externalparameters calibration is found and some effective amendments to
it is made to achieve a better calibration results. The article is mainly
divided into four parts to discuss.Firstly, the principles,steps andsystem model of the camera calibration was described;Secondly, thecommon methods for external parameters calibration was discussed,
the inadequacies which cycling conditions restrict external parameters
calculation and make it not be optimized fully in the optimization
process was elaborated, then a new amended method was designed
to solve the above shortcomings,according to optimized internalparameters and part-optimized external parameters,cycling condition
was re-selected and external parameters was calculated with Least
Squares Method,thus effective corrected values was obtained so thatthe calibration accuracy of the external parameters can be improved.
Thirdly, binocular vision system calibration experiments was carried
and detailed comparison of the calibration accuracy before and after
the correction of external parameters was made,it has been foundthat standard deviation, variance and the maximum error of threedimensional reconstruction after the correction of external parameters is
less than the calibration error before the correction;Finally, the summary
on research was given.

8561-48, Poster Session

A new AD device application in the CCD
signal process system
Su Lei, Beijing Institute of Space Mechanics and Electricity(China)A new Analog-Digital (AD) device is introduced in this paper, which is
newly applied on the signal process circuit of the high resolution remotesensing Charge-Coupled Device (CCD). Base on the signal process
circuit, the hardware and software design was introduced. In hardware,
the new AD had two selectable operated modes which are CDS modeand S/H (Sample Hold) mode. And the new AD output had LVDS
transmission. The AD’s output was transferred to the FPGA whose IO
pin was designed in special mode to receive the LVDS mode data. The
frequency of the LVDS data transmission should achieve over 320 Mhz.
In software, the software program was designed in VHDL language with
Xilinx FPGA to provide the driving signals to the AD and other devices,to handle the data and signals which were received from the AD andother devices in the signal process circuit. The program was introducedin brief chart and the program was divided in three main function
modules. The three modules were illustrated one by one with theirown figures. The different operate modes of the AD’s registers should
be selected in the program and the main function of the AD’s main
registers’ were validated and introduced.The image was got by using
this signal process system and was analyzed with the MatLab software.
According the Analysis this new AD signal process circuit had low noiseand high signal to noise ratio which was compared to the contemporary
circuit system.

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Conference 8561:
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8561-49, Poster Session

Measurement and analysis on infrared
imaging system performance under libration
Wang Jing, Ji ming, Xi’an Institute of Applied Optics (China)
The stabilization-aiming system is the important component elementof the precision strike tactical weapon system. Helicopter stabilizationaiming system is librated strongly because of the strong libration
resulted by the engine and airscrew during the helicopter flight, which
affect seriously the performance of the electro-optical system, and theviewing distance is an important performance of the electro-opticalsystem, so the problem how the helicopter libration affects the viewing
distance of the electro-optical system is badly in need of solution. A
method of measuring dynamic MRTD of infrared imaging system isadvanced in this paper, the relation between helicopter libration quantityand viewing distance is analyzed utilizing MRTD. The experimental
installation is designed and developed, The libration of helicopter
stabilization and aiming system is simulated by experimentation, theinfinity dynamic object is formed, based on this object, the test images
and data are gotten, and in order to get the MRTD of infrared imaging
system under libration, the test image and data are analyzed by image
processing and statistical methods. Experimentation result showsthat measurement of dynamic MRTD can be achieved commendably
utilizing the advanced method and experimental facilities, which
establishes basement for estimating the viewing distance effect fromlibration in the laboratory.

8561-50, Poster Session

Multiplexing of double cladding fiber sensors
for bending sensor
Libo Wu, Fufei Pang, Zhenyi Chen, Tingyun Wang, Shanghai
Univ. (China)
Double cladding fibers (DCF) have been researched comprehensively
for sensor applications. Through evanescent wave coupling, cladding
modes can be excited resonantly in the DCF. The transmission of the
DCF presents a band-reject filtering spectrum. According to the shiftof the transmission spectrum, many sensors have been developed
including the parameters of bending, temperature, refractive index,
strain and so on. However, since the transmission spectrum has arelative large bandwidth, it is difficult to multiplex such sensors inwavelength domain. In this paper, a multiplexing technique of DCF
sensors is proposed and demonstrated for bending sensor network. A
time-division multiplexing system with four DCF sensors in parallel isadopted in the experiment. We can control the optical path differenceof the four sensing branches reasonably to separate the four sensing
signals. To demodulate the sensing signals we adopt an edge filtering
technique, and a DFB laser pulse light source is used. As the DCF
is used as bending sensor, the resonant wavelength shifts to shortwavelength and the amplitude of that also changes when the bend
degree is deepening. According to the edge filtering effect, the shift of
the resonant wavelength results in the variation of the intensity of thetransmission light received by the detector. Through this property wecan get the bending information. The results show that the multiplexing
sensor system can have a good monotony when the curvature from 0
to 1.8m^-1. This time-division multiplexing system can provide a large
multiplexing capacity due to the high spatial resolution.

8561-51, Poster Session

Study on an ammonia sensor with highsensitivity in farmland based on laser
absorption spectroscopy technology
Ying He, Yujun Zhang, Liming Wang, Kun You, Yanwei Gao,
Anhui Institute of Optics and Fine Mechanics, CAS (China);
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Anning Zhu, Wenliang Yang, Institute of Soil Science,CAS(China)High nitrogen fertilizer input is the main manner to maintain thehigh-yield crops in farmland in China. The average application
quantity of nitrogen fertilizer in China is significantly higher than somedeveloped countries in the world. However, the nitrogen fertilizer
utilization efficiency is very low. Thus, high sensitivity sensing andon-line monitoring ammonia concentration were needed to quickly
acquire the soil nutrient information and to get the nitrogen fertilizer
utilization efficiency. A high sensitivity ammonia concentration
sensor used in farmland has been developed based on Tunable
Diode Laser Absorption Spectroscopy (TDLAS) technology, highfrequency modulation technique and long optical path technique.
TDLAS is a method to obtain the spectroscopy of gas molecule single
absorption line in the characteristic absorption spectrum region as
the characteristic of the distributed feed back (DFB) laser with narrow
line width and tunability. A sensor array formed with three ammonia
concentration sensors by distributed sensing technique was used
for ammonia volatilization experiment in a wide range of farmland. It
was verified that the performance consistency of the three ammonia
sensors was good and the sensor array realized the regional ammonia
concentration monitoring. Continuous measurement results showedthat the ammonia concentration influenced by the volatile source
location, wind direction, weather and other factors, and it was positively
correlated with the ammonia volatilization rate. The ammonia sensor
array is suitable for continuously ammonia volatilization monitoring ina wide range of farmland environment with its high sensitivity, rapid
response time without gas sampling.

8561-52, Poster Session

A pressure sensor based on highbirefringence fiber loop mirror
Tiancong Xu, Shuyang Hu, Dongmei Bai, Beijing Univ. ofTechnology (China)
Recently, high birefringence fiber loop mirror(HiBi-FLM) has been
widely used in gain flattening of erbium-doped fiber amplifiers,
multiwavelength and wavelength-switched fiber lasers, demodulationof fiber Bragg grating sensors and dispersion compensation. Because
the stress-induced high birefringence fiber (such as Panda fiber) is
sensitive to temperature and strain, HiBi-FLM can be used as sensor.
In this paper, a pressure sensor based on high-birefringence fiber
loop mirror is proposed and demonstrated in the first time. Part of the
HiBi-fiber is pasted on the out surface of a ring rubber gasbag thatis inflated and elastic, and this part will serve as a sensitive probe tomeasure the pressure. When outside pressure changes, the volume of
the gas in the ring rubber gasbag changes and it makes the strain of
the high-birefringence fiber variety. The relationship between shift of
the resonant wavelength (peak wavelength) and pressure is discussed
and experimentally researched. The formula of the relationship between
the resonant wavelength shift and pressure change is derived and it
shows that the shift is approximately proportional to pressure change.
Moreover, The sensing range and sensitivity can be adjusted by setting
the initial inner gas pressure. Experimental results show that thesensitivity is 1.63?10-3nm/Pa. This sensor also has many advantages
such as high sensitivity, polarization independent, easy manufacture,
low cost.

8561-53, Poster Session

Design of semiconductor ice box cooled bysolar power supply
Jie Hou, Hebei Univ. of Science and Technology (China);
Shiquan Qiao, Jun Zuo, Hebei University of Science andTechnology (China); Shuwang Chen, Hebei Univ. of Science andTechnology (China)
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A design of deepfreeze box is introduced in the paper, which is
supported by solar power supply. The box is constituted by four
major parts. There are a solar power panel, a solar charge controller, ahermetic box and a series of semiconductor frigorific pieces. The solar
power panel collects solar energy through the Photovoltaic effect. The
solar energy is stored in storage battery after being regulated by the
DC/DC converting circuit of the solar charge controller. The charge
controller circuit contains over-charging circuit, over-discharging circuit,short circuit, overload circuit and reversed polarity protection circuit.
The storage battery then supplies power to the deepfreeze box. The
solar charge controller can automatically track the maximum power
point in terms of the solar intensity. The cooling system is made up of
semiconductor frigorific pieces, whose power is exclusively provided
by solar energy. The whole device is small and portable, and can beapplied in some areas of environmental protection and energy saving.

was obtained. At the same time, the three-jump network increased therange of communication system and reduced the power. The protocol
adopts cluster head rotation mechanism, pick the higher power nodes
as the cluster head that that drifted higher over the life of the wholenetwork. The design uses CC1120 as the wireless transceiver chip,
MSP430FR5739 as main control chip, because MSP430FR5739
belongs to ferroelectric memory which can preserve data better.
A typical representative of competition-based periodic sleep MAC
protocol for wireless sensor network is S-MAC. Compared with thetraditional S-MAC protocol, TH-MAC has the advantages of low
crosstalk between frequency, low power and low latency. This algorithm
is suitable for the large-scale collection of data and information aboutindustry and agriculture and has an extensive range of applications.

8561-54, Poster Session

Theoretical study of the fiber nonlinear
polarization sensing based on whispering
gallery modes

Bending characteristics of long-period
fiber grating with a over-coupled resonant
wavelength
Chunying Guan, Xiaozhong Tian, Harbin Engineering Univ.
(China)The characteristics of LPFG fabricated using high-frequency CO2 laser
pulses exposure in conventional fibers have been well researched innumerous previous literatures. In comparison with other fabrication
methods, high-frequency CO2 laser pulses exposure has many uniqueadvantages, including high efficiency, low cost, low insert loss andeasily repetitive exposure. The bending responses of such a LPFG
depend strongly on the bending direction, and this character may solve
the problem of cross-sensitivity between bending and other measured
parameters.
In present paper, a special CO2-induced LPFG is fabricated in the
single mode fiber. There are two resonant peaks in the wavelength
range of 1000-1700nm, one of which is over-coupled while the otheris not. The grating period is 500 µm and the number of period is 50.
We stop the exposure when the amplitudes of two resonant peaks arenearly equal. The bending character of this LPFG is experimentallystudied in detail. The results show that the distance between thetwo resonant wavelengths has a periodic behavior along its circular
directions. Under a specific bending direction, the distance between
the two resonant wavelengths increases, while under the opposite
bending direction, the distance between the two resonant wavelengths
decreases. Also the distances between the two resonant wavelengths
change nearly linearly against the curvature under the two bending
direction mentioned above. The bend sensitivities under these two
bending directions are 7.19nm/m and 3.13nm/m, respectively. In
addition, with further bending under the direction which makes the
distance increases, the over-coupled peak split into two peaks, which
has not been found in normal unover-coupled LPFG.

8561-56, Poster Session

Rui Yang, Hai-peng Jin, Yunnan Univ. (China)
The optical circular micro-cavity has been applied in highly sensitive
sensors because of its whispering gallery modes (WGMs) with very
high Q quality and very small mode volume. Fiber was a kind of opticalcircular micro-cavity structure, in which WGMs were excited in its
cross section by evanescence field. The spectral position of the WGMs
shifted in response to the change of correlative refractive index.
However, electromagnetic field in optical fiber was limited within two
dimensions at wavelength range. As a result, intense light power density
enough to excite the nonlinear interaction was easy to obtain in fiber.
The nonlinear polarization interaction caused by strong incidence lightfield or external field results in slight change of refractive index of thefiber. It was the WGMs of fiber to detect this slight change of refractive
index. Therefore it provides an observable sensing method for studying
the nonlinear refraction effect of fiber.
In this paper, basing on the quantum model of WGMs in cylindrical
optical micro-cavity, resonance spectral shift equation which indicatesthe variation on spectral position of WGMs with refractive index offiber’s dielectric was derived using quantum perturbation theory. Hence,
the refractive index changes caused by the nonlinear effect of fiber
were reflected through the observable resonance frequency shift. The
calculation showed that a sensitivity of approximately 50 nm per RIU(refractive index unit) was achieved due to the extremely high Q factor
associated with the WGM.

8561-57, Poster Session

A HBF strain sensor with piezoelectric
ceramic based on Sagnac LM
Lidan Yin, Li Wang, Beijing Univ. of Technology (China)

8561-55, Poster Session

FDMA/TDMA hybrid MAC protocol for
wireless sensor network
Qi Qi, Hong Wu, Lei Ji, Beijing Institute of Technology (China)
An efficient MAC protocol is one of the keys for long-time working andhigh-efficiency communication of WSN. In this paper, we develop a
new MAC protocol that based on hybrid FDMA/CDMA technology withthree-jump network for achieving long-distance and low power aboutdata transmission. This protocol combines the advantages of both
FDMA and TDMA. The communication of cluster heads is based on
FDMA technology which can decrease the crosstalk between different
frequency and the cluster heads can identify each other easily; the intercluster communication is based on TDMA technology to achieve basic
time synchronization. Then the time synchronization of the network

The fiber sensors have the advantages of high sensitivity, light weight,
small size, resistance to electromagnetic interference and corrosion
resistance. Because the HBF sensors have the better characters than
traditional ones, so in real life, HBF sensors have been more widelyused, especially strain sensors are used in the monitoring of buildings
and bridges. In the experiments, due to the sensing characters of
Sagnac LM, especially in the temperature sensors experiments, thetrough (or peak) of each intervention is not completely overlap, which
is a zero error, so the experimental data generally take the distance of
the wavelength shift, rather than specific wavelength of the trough (orpeak) data. It’s more difficult to compare the data of every experiment.
The strain sensor can be used to compensate the zero error in theexperiments.
This article about HBF strain sensing characters is divided into threeparts.
The first part, study the stress-sensing characters of high birefringence

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Conference 8561:
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and calculate the corresponding theoretical data and stimulate
the graph, in the 0 - 120V (providing to piezoelectric ceramic) andwavelength shift (nm), in theory.

8561-58, Poster Session

is performed by using dual-frequency laser interferometer, so as
to find corresponding relationship between peak wavelengths anddisplacements of the reflecting mirror. With the quadratic polynomial
fitting method, the corresponding relation is described to get thebenchmark curve. The linearity is calculated according to the calibration
curve and the benchmark curve. Finally, precision analysis about themeasurement system is described, aiming at such factors affecting themeasurement accuracy as light source, pinhole diameter, resolutionof the spectrum analyzer, the optical lens design and optimization
method, the data processing method, the calibration method,etc. The
experimental results indicate that the measuring range of the chromatic
confocal system is 20mm, and the measuring precision can reach
10µm, the linearity is relatively good. And it is proved that the designed
system can satisfy the rapid displacement measurement requirementswith very high precision.

PH sensor using fiber Bragg grating basedon swelling of hydrogel

8561-60, Poster Session

The second part, compare the experimental graph with theoreticalgraph and compare the difference between elliptical fiber and Panda
fiber.
The last part, apply the HBF strain sensor to optical fiber temperaturesensing experiments, predict the compensated voltage to zero error,
which exists between the foregone experiment and this experimentwhen the voltage is zero, before this tested experiment and compare
the predicted data and experimental data.

Xiaohua Lei, Chongqing Univ. (China); Bo Dong, Jianmin Gong,
Anbo Wang, Virginia Polytechnic Institute and State Univ.
(United States); Weimin Chen, Chongqing Univ. (China)
The pH value is a very important parameter in environment monitoring.
When the area under investigation is quite large, pH measurement at
multiple points is preferred.
Because hydrogel, which is a blend of PVA (vinyl alcohol) and PAA(acrylic acid) polymer, is sensitive to pH value, many pH sensors
based on hydrogel were developed. One type of pH sensor is basedon hydrogels which are coated directly onto optical sensors. For thiskind of sensors, Hydrogel coating is prone to separate from the fiber
sensors; therefore this method is not very reliable. But fiber sensors
are easy to be multiplexed, so this type of pH sensor is easy to befabricated for multi-points monitoring. The other type of pH sensor isbased on swelling of hydrogels which is transferred to deflection of a
micro-mechanic structure and then the deflection is detected by othersensors. For this type of sensor, hydrogel and other sensors are notconnected, so it is more sensitive and reliable, but hard to be fabricatedfor multi-points monitoring.
Here we proposed a new pH sensor based on pH sensitive hydrogelswelling detection by a fiber Bragg grating, which combines advantagesof those two methods. The deflection of a silica membrane due to pH
value change induced hydrogel swelling is measured by the center
wavelength shifts of a fiber Bragg grating epoxied on the membrane.
The relation between center wavelength shifts of the fiber Bragg gratingwith the hydrogel swelling behavior was studied experimentally. Around100pm shift of the fiber Bragg grating center wavelength was observed
when the pH value was changed from 4 to 7 or from 7 to 10 by using
pH standard solutions, which fundamentally proved the feasibility of thismethod for pH detection.

8561-59, Poster Session

Study of a novel micro-displacement
measurement system based on chromatic
confocal technology
Xiaofei Liu, Wenyi Deng, Chun-Hui Niu, Boshi Jin, Beijing
Information Science & Technology Univ. (China)
A chromatic confocal system for measuring micro-displacement
is designed and its performance is studied in the paper. First, themeasurement principle of the system is introduced, and an actual
measurement system is built based on chromatic confocal technology.
Second, Gaussian fitting algorithm is used to fit every group of
experimental data in order to obtain the peak spectral response curve,
and to obtain the wavelength corresponding to the peak.The LM
algorithm(Levenberg-Marquardt algorithm) is presented to solve theparameter vector of Gaussian function.The peak position parameterstands for the corresponding wavelength of every peak of the spectral
response curve. And then, the calibration to the experimental system

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An experimental study about humidity
sensors based on tapered optical fibers
Xinghu Fu, Guangwei Fu, Weihong Bi, Yanshan Univ. (China)
In order to ensure the normal living and production, it is necessary
to monitor air moisture content in different environment, including air
conditioning, sterilizers, nutritional products manufacturing, and so on.
Optical fiber sensors present advantages such as small size, immunity
to electronic magnetic fields, high sensitivity, etc. Moreover, they canbe used to detect the humidity induced refractive index changes.
Thereby, a humidity sensor is proposed for detecting air moisture
content based on tapered optical fiber. According to optical energy
transmission theory, the sensing mechanism of humidity sensor isdescribed by analyzing the evanescent field around the sensing fiber.
The relationships between the dimensions and spectral characteristicsof the taper have been analyzed, respectively. The results show thatthe taper shape is important for designing a humidity sensor andthe spectral characteristics variation can reflect the evanescent field
intensity. A straightforward experiment is performed to prove thewavelength dependence of the sensitivity. It is mainly composed of an
ASE broadband source, an optical circulator, a tapered optical fiber anda spectrum analyzer. The fitting curves can be obtained by comparing
the characteristic wavelengths and humidity, and the errors are also
given. The humidity is analyzed in different air moisture content. The
humidity measurement resolution is 1% as the measuring range varies
within 50-95%. The characteristic wavelengths have a blue shift anddecrease as increasing humidity. Thus, the high dynamic performance
can allows this sensor to be used for humidity monitoring in time.

8561-61, Poster Session

A novel safety light curtain system using ahemispherical mirror
Yusuke Kenjo, Ryosuke Suzue, Huimin Lu, Kohei Miyata,
Shiyuan Yang, Seiichi Serikawa, Kyushu Institute of Technology(Japan)Light curtain systems are used to detect intruders in various casesand places. However, it is necessary to adjust the position of the lightdetecting element accurately in order to receive the irradiating laser
light. We propose a new type safety light curtain system that uses ahemispherical mirror and an LED in this research. A hemisphericalmirror can reflect irradiating lights surroundings of 180° in the verticaldirection and 360° in the horizontal direction. So that even if an LED
is arbitrarily set up, the LED irradiating light can be reflected by thehemispherical mirror, when the LED is at a position that is higher thanthe hemispherical mirror, and the light detecting element can receive
the LED irradiating light. In the case that the light of LED is intercepted
when an intruder passes between the LED and the hemispherical mirror,
the output voltage of the light detecting element decreases. We canset a proper threshold voltage value of the detecting element to judge

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whether an intruder passes or not. Our system uses a microcomputer
to judge the output voltage of the receiving element with the thresholdvoltage value and the LED output light is modulated by 10kHz inorder to avoid the influence of the surrounding turbulence light. Our
experiment succeeded to detect intruder using the proposed system
without accurate light axis setting.

8561-62, Poster Session

A single-photon detector without cooler
Bing Zhou, Fu-yu Huang, Dong-sheng WU, Jie Liu, Shijiazhuang
Mechanical Engineering College (China)
Avalanche photodiode (APD) single-photon detector, which has been
the research pivot of single photon detection technology, has theadvantage of high quantum efficiency, low power consumption, large
performance spectrum range, small volume, low operating voltage andso on. In the detection, APD usually works in Geiger mode and the bias
voltage is higher than avalanche voltage. But when the temperaturerise, the avalanche voltage would become higher and the diode’s
noise would rapidly increase around the avalanche voltage. Therefore
APD single-photon detector is usually cooled by using fluid nitrogenor thermoelectricity cooling to stability APD’s work circumstancetemperature to ensure avalanche voltage stabilization and also deduce
detector noise and enhance the SNR. The adoption of cooler increases
system complexity and restrict the serviceable range of the detector.
One type of single-photon detector that without cooler, which is mainly
consisted by noise voltage control circuit and precise pulse width
detection circuit, is presented. The noise voltage control circuit isusing the characteristic the noise rapid increase in avalanche voltage.
The detector signal after forward and video amplifier is measured.
When noise voltage exceed a certain range, the bias voltage would
be decreased; when noise signal minished, the bias voltage would be
increased. So the bias voltage of APD is dynamically fixed by certain
voltage. When the avalanche voltage changes with the temperature,
the noise character nearby avalanche is resemble. So the bias voltage
could be stabilized based on noise character. The detector’s output
SNR would descend greatly if there was no cooler, and the phonon
avalanche signal would not measured efficiently by the tradition extent
detection. Considering the difference of time width between photon
avalanche signal and noise signal, the precise pulse width detection
circuit is designed. It can filter the narrow noise signal and only detectphoton avalanche signal which has larger pulse width efficiently.

are investigated, and the sensitivity of proposed sensor is also given.
The results indicate that the resonance wavelength shifts to longer
wavelength and the resonance peak broadens when the thickness ofgold film increases, and the spectral tuning of the resonance can be
more efficiently realized by changing the TiO2 layer thickness. The
resonance wavelength is also sensitivity to the refractive index of theliquid analyte, while the resonance wavelength doesn’t move basicallywhen the fiber core size, the pitch between air holes, and the size of airholes vary. The maximal sensitivity of the proposed sensor reaches to
10-4/RIU.

8561-64, Poster Session

Effects of diameter on characteristics of along-period fiber grating
Xiaobei Zhang, Zhaohui Yin, Yang Li, Fufei Pang, Yunqi Liu,
Tingyun Wang, Shanghai Univ. (China)
As a transmission type fiber passive device, the long-period fiber
grating (LPFG) has been greatly applied in optical fiber communicationand sensing fields. LPFGs are sensitive to variety of the surrounding
medium, while the sensitivity can be enhanced by reducing the fiber
diameter through tapering or thinning the fiber using the flame torch,laser and chemical etching.
In this paper, effects of diameter on characteristics of a LPFG arepresented, such as the coupling coefficient, refractive index (RI)
sensitivity, resonant wavelength and the shape of attenuation dips. By
numerical simulations, the couplings between the core mode and theHE, EH cladding mode increase as the fiber diameter decreases. EH
cladding mode increases faster than that of HE cladding mode. Whenthe fiber diameter reduces to a certain dimension, coupling of EH
cladding modes are analogous to HE cladding modes. Therefore, thecoupling of EH cladding mode must be taken into account. Moreover,comparing with LPFGs in common fiber, the depths and bandwidths of
the attenuation dips of LPFGs in thinner fiber vary faster as functions of
the grating period, the grating number, and the RI modulation depth dueto the increases of the couplings coefficients.

8561-63, Poster Session

The resonant wavelength shifts to the shorter wavelength and the
RI sensitivity is greatly enhanced when reducing the fiber diameter.
Therefore, we can utilize the higher sensitivity of high-order cladding
mode at a suitable wavelength by thinning or tapering the fiber.
Furthermore, the sensing resolution and the cladding mode can also
be selected by controlling the fiber diameter. We also find that the RI
sensitivity of LPFG increase as a function of the exponential shapewhen the external RI increasing to the cladding RI whatever the fiber
diameter is.

Surface plasmon resonance sensor basedon multihole optical fiber with TiO2 layer

8561-66, Poster Session

Chunying Guan, Di Gao, Harbin Engineering Univ. (China)
The surface plasmon resonance (SPR) is defined as the physicalprocess that surface plasmons which progating at the metal/dielectricinterface are excited. The surface plasmons are extremely sensitive toeven small changes of the refractive index of the dielectric. The fiber
optic SPR sensor is a unique combination of optical fiber technology
and SPR technology. In the past few decades, because of theadvantages of high sensitivity, small size and real-time monitoring,the optical fiber SPR sensor has been widely applied in biochemical
detection, environmental and food testing, structural health monitoring.
A novel SPR sensor based on the multihole optical fiber is proposed
and numerically characterized in present paper. The six air holes in themultihole fiber are firstly covered by a thin gold film which supports thesurface plasmons, and then coated with a uniformed titanium dioxide
layer which is used to facilitate spectral tuning of the device andprotect the gold film. The finite element method is used to analyze thecharacteristics of the surface plasmon resonance sensor. The effectsof the size of fiber core and the air holes, the pitch between air holes,
the thickness of the gold film and titanium dioxide layer on the sensor

The implementation of zero-phase highpass filtering in interferometric fiber-optic
hydrophone system
Yaowen Xiao, Tsinghua Univ. (China)
We need high-pass filtering in interferometric fiber-optic hydrophonesystem. In this paper, two methods of zero-phase high-pass filtering
are introduced. The two methods are based on infinite impulse
response (IIR) filter and frequency filtering alternatively. The forward
and reverse filtering, as the name suggests, is filtering the input data
in sequence and in reverse successively. And according to the orderof the operations, the method can be divided into two sub-methods.
One is FRR, which means forward filter, reverse filter, reverse output.
And the other is RRF, which means reverse filter, reverse filter, forward
output. Both FRR-method and RRF-method can completely eliminate
the influence of the nonlinearity of the phase-response to achieve
the zero-phase filtering. Frequency method means doing filtering infrequency domain directly. We get the frequency-domain representationby using Discrete Fourier Transform (DFT). As to the frequency range we

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Conference 8561:
Advanced Sensor Systems and Applications V
want to filter out, we simply make it zero. Then we use Inverse Discrete
Fourier Transform (IDFT) to get the time-domain representation of theoutput data. Both the two methods can shorten the data processing
time compared to finite impulse response (FIR) filter on the expense ofmemory cost, which is also discussed in this paper.

8561-67, Poster Session

Experiments research on motion detection
accuracy of joint transform correlator
Guang Lin, Qi Li, Huajun Feng, Zhihai Xu, Zhejiang Univ. (China)
Typical JTC includes laser sources, Fourier lenses, image sensors,
spatial light modulators, and etc., and this article discusses theinfluence factor on JTC motion detection accuracy. The shapes,
brightness uniformity of the correlation peak were closely related to thedetection accuracy, and the former has more significant influence thanthe latter. As the same time we found in experiments, the laser power
level has an important influence on the detection results: the laser
power level of input image influences the graph of power spectrum, andchanges the last shape of correlation peak image. The image quality
first rises and then reduces as the power rises; the laser power levelof the output power spectrum affects the collected correlation pattern,
and changes the SNR of the correlation peak image. The image quality
first rises and then reduces as the power rises, too. The effectivenessof these conclusions is verified among different input images during thispaper.

8561-68, Poster Session

The design of multi-parameter detection
platform of drinking water based on twoelectrode voltammetry

optical cavity and a tunable external cavity diode laser (ECDL) system.
The performance of the system was demonstrated by using the carbon
dioxide as the sample gas. Both high resolution and medium resolution
spectra of the detected gas can be recorded. The vibration-rotational
spectra of CO2 molecule at room temperature was obtained in the wave
number range of 6450~6530 cm-1, which has a medium resolution
and can be used to compare with the standard database of CO2 line
and to identify the existence of the CO2 in the gas mixture. While ahigh resolution spectra of CO2 can also be recorded, and be used toevaluate the relationship between the spectral line intensity, line-width
and the gas concentration. Using the high resolution spectrum of theCO2 molecule weak absorption line of 6358.65cm-1, a sensitivity of
1.98?10-7 cm-1 was achieved by using the detection system, and canbe used for pollution gas detection in the environment.

8561-70, Poster Session

A new type fiber-optic accelerometer
Chang Yang, Tianjin Univ. (China); Hongpu Zhou, Min Zhang,
Tsinghua Univ. (China); Fajie Duan, Kai Wang, Tianjin Univ.
(China); Yanbiao Liao, Tsinghua Univ. (China)
A novel all-metal fiber-optic accelerometer based on Michselsoninterferometric configuration is proposed by using mass blocks
and flexible reed structure.The axial direction of the sensing arm isconfigured to be parallel to the direction of acceleration, which directlytransform the applied acceleration to fiber deformation in axial direction,
which increases the acceleration sensitivity of the sensor.The reed serve
as a transducer, by alternating which the sensor’s performance can be
improved. And metal material is adopted to enlarge sensor’s applied
range. Using the reed of 1mm thick and the mass block of 208g, theacceleration sensitivity of 556rad/g(55dB) is achieved by this structure.
In the case of 10-5rad noise floor, the minimum detectable accelerationis 20ng.

Yazhuo Li, Jiali Wei, Xiaoping Wang, Zhejiang Univ. (China)

8561-71, Poster Session

A novel detection and analysis platform which is based on twoelectrode electrochemical voltammetry system has been developed for
multi-parameter measurement of drinking water. There are three unit
in this platform, multi-sensor unit, hardware system unit and control
and processing software unit. After choosing detection objects on
computer, the control and processing software unit can control the
hardware system unit apply corresponding potential on appropriate
working electrode automatically. Currents can be collected on counterelectrode and sent to computer for data processing. The multi-sensor
unit contains Ti, Pt, Au, etc. noble metal electrodes as working
electrodes and a large area ringlike stainless steel was as counterelectrode. Comparing with conventional three-electrode voltammetry
system, reference electrode has been eliminated in this platform bymechanical improvement of sensor array. This platform has been
employed on detection of two common parameters in drinking water,electric conductivity (EC) and concentrations of heavy metal ions. In
EC measurement, bipolar pulse with high frequency has been applied
on Pt working electrode. In heavy metal ion of lead detection, staircase
wave stripping voltammetry was applied on Ti working electrode.
This detection platform owns high mechanical strength sensor, lowmaintenance requirements and easy to use, it could be used for
drinking water quality monitoring in laboratory or industry locale.

The research and implementation of mobile
sink for the regional information monitoring
system based on WSN

8561-69, Poster Session

Gas detection system using off-axis cavity
enhanced absorption spectroscopy
Wei-dong Zhou, Zhiwei Wu, Zhejiang Normal Univ. (China)

Biyao Shen, Hong Wu, Beijing Institute of Technology (China);
Lei Ji, BEIJING SHIDAIJINPU S&T DEVELOP CO.,LTD (China)
As a new area of research, Wireless Sensors Network (WSN) has
played a significant role in regional information monitoring area for its
potential practical value. However, the promotion of WSN has been
limited because of its short lifetime. In a traditional multi-hop WSN,
the nodes close to the static Sink easily suffer the energy failure fortransmitting large amounts of extra data. This leads to an “energyhole” phenomenon in WSN and finally causes the early death of thewhole network. To solve this problem, a mobile Sink was brought in
to balance the energy consumption of the whole network. This Mobile
Sink Wireless Sensors Network (MSWSN) has recently received a lot of
attention from the research community. Based on this view, the paper
presents a design proposal of a mobile Sink used in regional monitoringarea. To achieve the design requirement, the hardware platform isdesigned based on a LM4F232H5QD ARM Cortex-M4 processor andthe driver program and applications are designed based on embedded
real time operation system µC/OSIII. This mobile Sink could not onlytransmit data, but also calculate its location through a 3-axis analog
accelerometer and then reveal the information of its current location
through OLED. Compared with traditional WSN, MSWSN shows
appealing characteristics of providing longer network lifetimes and theflexibility to adapt dissemination strategies according to applications’requirements and has proved to be more efficient.

Abstract: A real-time, on-line trace gas detection system based onhigh-resolution off-axis cavity enhanced absorption spectroscopy(OA-CEAS) technology was developed by employing a high finesse
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8561-72, Poster Session

The study of intelligent temperature
measurement based on optic fiber
Xiaoqiao Xing, Yuexiang Peng, Beijing Univ. of Technology(China)The Sagnac loop mirror of high birefringence fiber is developing greater
more than other fiber because it has the advantages of high precision,
wide spectrum and simple structure in applications.
In this paper, general theory of Sagnac loop mirror of high birefringencefiber is presented. Since Sagnac loop mirror of high birefringencefiber is more sensitive to its environmental temperature, an intelligent
temperature measurement system based on Sagnac loop mirrorof high birefringence fiber is designed. A 1550nm-laser is used assource light going through the high birefringence fiber Sagnac loop
mirror. The amplitude of output beam is converted into electricalsignals with Photo-Diode (PD), and the signal is collected by the
MCU to complete the analog-digital conversion. After calibration, thetemperature is calculated, and then shown on LCD displayer. Various
parts of the electronic measurement system are introduce in details,
containing MCU C8051F020 microcontroller, its internal AD-convert,
calibration program and measurement program of temperature. In
addition, the paper also introduces the structure and working principleof the high birefringence fiber Sagnac loop mirror system. The fiber
optic temperature measurement system is compact, solid with goodportability, as well as independent real-time analysis of data processing
capability. It’s provides a good preliminary basis for implementation
the new fiber-optic temperature measurement system. And this system
has broad application prospects of a good practice. The arrange oftemperature measurement is from 30°C to 50°C with accuracy ±0.2°C
in recent research experiment.

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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies II
Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8562 Infrared, Millimeter-Wave, and Terahertz Technologies II

8562-1, Session 1

Review of THz wave air photonics (Invited
Paper)
Xi-Cheng Zhang, Univ. of Rochester (United States)
Summary
THz wave air photonics involves the interaction of intense femtosecond
laser pulses with air. The very air that we breath is capable of generating
and detecting THz field strengths greater than 1MV/cm and usefulbandwidthfrom 0.1 THz toover 10 THz.Remote broadband THz wave
sensing is feasible.
Introduction
Laser-induced-gas-plasma can be used to generate intense, coherent,
broadband, and highly directional THz waves through a nonlinear
optical process.Moreover, plasma in ambient air or other selected gases
can be used as a THz wave sensor.One technique, termed THz air
biased coherent detection (THz-ABCD), provides superior bandwidth(0.1 to 40 THz), detection sensitivity (heterodyne method), andfrequency resolution (MHz).

demonstrated. While some applications such as sensing in remote
atmospheric locations may be feasible, public safety must also be
considered. These limitations are motivation for improvements to thistechnology, and/oralternativesolutions for remote THz spectroscopy.
In the future, we have to address scientific and technical concerns,
provide guidelinesand solutions to satisfy safety issues, and develop
further approachesthat make use of THz wave air photonic systems andtheirunique abilities.
Conclusions:
Recentobservations that THz radiation is able to modulate both thefluorescence and acoustics of laser-induced plasma in air,means that
THz-REEF or TEA not only presentfeasible solutionstowardremote THz
wave detection, but also open exciting new areas of basic research. The
fluorescence technique could, for example, exploit the Stark effect todirectly measure rectified THz fields inside of a filament core, providing
evidence of potentially enormous field strengths that are unable tobe probed directly. Furthermore, acoustic techniques could make itpossible to study solids or liquids with high absorption coefficients
byindirectly studyingchanges ina sample’sacoustic propertiesunderillumination of high-field THz radiation.
Reference:

Here we review THz wave generation and detection techniques, sensing
methodologies,applications for material classification, remaining
challenges, and future opportunities for this rapidly evolving area of
research that transcends the”gap”once existing between optics andelectronics.

B. Clough, J.M. Dai, and X.-C. Zhang, Materials Today, review paper,Jan., 2012.

THz wave air photonics

Optimization of receiver parameters ofan optical array receiver for deep-space
optical communication during Earth-Mars
conjunction phase (Invited Paper)

Fig. 1a illustrates this all-optical process for the generation anddetection of THz waves by using an air emitter and sensor, the system
is called as THz air-biased-coherent-detection (THz ABCD). The laserinduced air plasma, shown as a bright spot in Fig. 1b, emits a very
intense, highly directional, ultra-broadband THz field. Similar to thewidely used generation and detection of THz waves in electro-optic
crystals by second-order optical nonlinearity, the THz waves can bedetected by the third-order optical nonlinearity in air.
Challenges, Limitations, and Opportunities
Although laser air photonics technology has opened new possibilities
for application,many areas remain for improvement.Remote sensing
and standoff detection with THz waves could be considered one of
the most challenging topics in THz sensing. Due especially to strong
water vapor attenuation in the THz frequency range and insufficient THz
power, broadband THz sensing has been limited to short distances (afew meters). The generation of air-plasma near the target(s), throughlaser excitation, provides one approach to remote detection. The THzABCD method offers broadband sensing capabilities, but the THzinduced second harmonic signal cannot be easily collected from eithera backwards or sideways direction. It is also necessary to provide ahigh voltage local oscillator bias that cannot be readily placed near the
remote target for coherent detection.
While remote THz wave generation (>100 meters) is realistic, coherent
remote sensing remains extremely challenging. Currently, the only
known solution is to use a two-color laser field to generate air-plasmanear the target, measuring THz wave information indirectly throughTHz-field-induced changes in plasma fluorescence or acoustics. THz
air-plasma detection through THz radiation enhanced emission offluorescence (THz-REEF) or THz enhanced acoustics (TEA), in contrast
to nearly all other THz wave sensing methods,enables omnidirectionalsignal collection, and significantly mitigates the problem of THz
absorption by atmospheric moisture. Although both remote generationand detection have been demonstrated separately, it remains to
combine these laboratory demonstrations to realize real world THz
remote spectroscopy of explosives or other hazardous materials.

8562-2, Session 1

Ali Javed Hashmi, National Univ. of Science and Technology(Pakistan); Ali Asghar Eftekhar, Ali Adibi, Georgia Institute ofTechnology (United States); Farid Amoozegar, Jet Propulsion
Lab. (United States)
NASA deep-space ventures so far have relied upon a global Radio
Frequency (RF)-based Deep-Space Network (DSN) to capture thecommunications signal returns from distant planets. The current RF
technology is unable to fulfill the demands of such ventures due toconstraints like huge free space loss and limited available spectrum in
RF region of Electromagnetic spectrum. In this paper, we present thechannel modeling, optimization of various receiver parameters, and link
analysis of a deep-space optical communication link between a spacecraft at Mars and an Earth based optical array receiver, during EarthMars conjunction phase. The simulation results show that optimizationof link parameters is essential to maximize the performance of analready power-starved deep-space optical communication link. The
calculations of achievable data rates show that optical communication
systems operating at 1.06 (IR frequency) can provide an order ofmagnitude greater bandwidth compared to the current RF technology.
This paper presents the analytical results during Earth-Mars conjunction
phase, which represents the worst case channel conditions for an
optical communication link between Earth and Mars.

Using an intense laser with mJ pulse energy for manypracticalapplications is also a challenge. The focusing of high intensity opticalpulses over long distances with precision, and practical controlof the THz amplitude and phase at these ranges has not yet been

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Infrared, Millimeter-Wave, and Terahertz Technologies II

8562-3, Session 1

Study of terahertz spectroscopy using an
infrared FTS system
Shaoliang Li, Kangmin Zhou, Wenying Duan, Zhenhui Lin, Qijun
Yao, Shengcai Shi, Purple Mountain Observatory (China)
Fourier transform spectroscopy (FTS) is a measurement techniquewidely used in characterizing the spectrum of light sources and thefrequency response of detectors. Some “ghost” spectral lines, however,are often observed in measured Fourier transform spectra, such as
high-frequency harmonics of the light source due to multiple reflectionsin the measurement system and unexpected high frequency lines owing
to low-frequency interferences in the data acquisition. Here we study
the effects of multiple reflections and low-frequency interferences on
the THz spectra measured by a Fourier transform spectrometer fordifferent THz sources and detectors. Multiple reflections happen mainly
because there are several metal planes such as the detector front
part, signal source output plane in the FTS system. During the Fouriertransform process the reflected signals are treated as normal signal
so that “harmonics” can be witnessed on the final spectra. Details
are given in the theoretical inductions part, together with a diagram
illustration. Later, we identify the several factors in simulation based on
the theoretical assumption to match the experiments’ results. Finally,corresponding experiments are designed to figure out quantitatively
the contribution of the several planes to the final result in our system.
Low-frequency interferences are generally introduced by the peripheralssuch as read-out circuits. As shown in the theoretical induction,
low-frequency noises coupled with the sampling frequency will form
apparent high-frequency signals in the final spectra. An artificial lowfrequency “noise” is introduced as reference to identify the relationshipbetween the sampling frequency and the interference frequency.
Experimental and simulation results will be presented.

8562-4, Session 1

Design of 800x2 low-noise readout circuit fornear-infrared InGaAs focal plane array
Zhangcheng Huang, Huang Songlei, Jiaxiong Fang, Shanghai
Institute of Technical Physics (China)
InGaAs near-infrared focal plane array (FPA) have important applicationsin space remote sensing. A design of 800?2 low-noise readout
integrated circuit (ROIC) with pitch of 25µm is presented for a dual-band
InGaAs FPA. The thermal noise of input-stage amplifier which is the
major noise source in ROIC is reduced by increasing the load capacitor
and a bias voltage in the range of ±5mV is obtained by optimizing thetransistors in the input-stage amplifier. The circuit has been fabricatedwith 0.5µm 5V mixed signal CMOS process. Test results show that
ROIC noise is less than 1E-4 V with dynamic range larger than 84 dB,
and a dual-band 800?2 InGaAs focal plane array with D* above 1E12
cmHz1/2/W is obtained after interfaced with InGaAs chips.

8562-5, Session 1

Shifting media for terahertz carpet cloak andoverlapped effects
XiaoFei Zang, YiMing Zhu, Bin Cai, Univ. of Shanghai for
Science and Technology (China)
Based on transformation optics and complementary media (folded
geometry), levitative carpet cloak and overlapped effects (anti-mirror
effects) can be realized. In normal case, the levitative carpet cloak
is limited by the shape of the invisible object, and the early folded
geometry method can just make two objects with different shapes
appear as only one. Here, based on transformation optics and finite
element simulations we propose an anisotropic but homogeneous

shifting media. It includes a free region between the complementary
media and compressive region that can shift an object from originalplace to another place with variable distance in terahertz (THz) region.
As a result, an arbitrary shaped object levitated on a flat perfect electric
conductor ground and covered with the shifting media cannot be
detected, leading to the levitative and shape-independent carpet cloak.
Furthermore, overlapped effects such as making two separated objects
with the same shape appear as only one, can be also realized by using
this kind of shifting media.

8562-6, Session 2

Computer processing of image capturedby the passive THz imaging device as aneffective tool for its de-noising (Invited Paper)
Vyacheslav A. Trofimov, Vladislav V Trofimov, Lomonosov
Moscow State Univ. (Russian Federation); Yuan-meng Zhao,
Chao Deng, Xin Zhang, Cun-lin Zhang, Capital Normal Univ.
(China)We demonstrate real-time computer code improving significantly thequality of nosed images captured by the passive THz imaging system.
The code is not only designed for a THz passive device: it can beapplied to any kind of such devices and active THz imaging systems
as well. The performance of current version of the computer code isgreater than one image per second for a THz image having more than
5000 pixels and 24 bit number representation. Processing of THz single
image produces about 20 images simultaneously corresponding tovarious spatial filters. We develop original spatial filters which allow one
to see objects with sizes less than 2 cm. For images with high noise
we develop an approach which results in suppression of the noise afterusing the computer processing and we obtain the good quality image.
With the aim of illustrating the efficiency of the developed approach wedemonstrate the detection of the liquid explosive, ordinary explosive,
knife, pistol, metal plate, CD, ceramics, chocolate and other objects
hidden under opaque clothes. The results demonstrate the highefficiency of our approach for the detection of hidden objects and they
are a very promising solution for the security problem.

8562-7, Session 2

A new approach of graph cuts based
segmentation for thermal IR image analysis(Invited Paper)
Sumit Chakravarty, SGT, Inc. (United States)
Thermal Infra Red images are one of the most investigated and popular
data modalities whose usage has grown exponentially from humble
origins to being one of the most extensively harnessed imaging forms.
Instead of capturing the radiometry in visible spectra, the thermal
Images focus on the near to mid Infrared spectra thereby producing
a scene structure quite different from their visual counterpart images.
Also traditionally the spatial resolution of the infra red images has been
typically lower than traditional color images. The above reasons havecontributed to the past trend of minimal automated analysis of thermal
images wherein intensity (which corresponds to heat content) and to alesser extent spatiality formed the primary features of interest in an IR
image.
In this work we extend the automated processing of Infra red images byusing an advanced image analysis technique called Graph cuts. Graphcuts have the unique property of providing global optimal segmentation
which has contributed to its popularity. We side step the extensive
computational requirements of a Graph cuts procedure (which consider
pixels as the vertices of graphs) by performing preprocessing toobtain a short list of candidate regions. Features extracted on thecandidate regions are then used as an input of the graph cut procedure.
Appropriate energy functions are used to combine traditionally used

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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies IIgraph cuts feature like intensity feature with new salient features likegradients. The results show the effectiveness of using the above
technique for automated processing of thermal infrared images
especially when compared with traditional techniques like intensity
thresholding.

8562-8, Session 2

Research on a project of the new airborne
polarization hyperspectral imager
Huan Li, Jia ZHAO, Feng Zhou, Xu-ling LIN, Hai-bo Zhao,
Beijing Institute of Space Mechanics and Electricity (China)
Polarization hyperspectral imagers combine polarization technology,
spectral technology and imaging technology, get both the image of thetarget and the polarization and spectrum of the pixel to recognize thematerials on the objects, have broad applied foreground on airborne
remote sensing domain. That arrests extensive attention abroad.
Polarization hyperspectral imagers are compared with conventional
hyper-spectral images, added polarization function, improve thecapability on two aspects.
One is on account of the spectrum is divided into a lot of parts ona hyperspectral imager, several nanometer as usual, that results theenergy collected by each pixel reduced, and retricted by signal-to-noise
ratios (SNR). However, the low SNR affects the image observed, butpolarization is not sensitive to the light, and it can get good image on
the condition of low SNR.
The other is that hyper-spectral imager is not sensitive to observing
angle, whenas polarization is much difference on the different position.
Therefore when the conventional hyper-spectral imager can’t get goodrecognization, we could make use of the polarization hyperspectral
imaging to recognize farther.
This paper brings hyperspectral technology and polarization image
together. On the basis of geometrical optics theory and polarization
theory, puts forward a new polarization hyper-spectral Imaging
technology. That could get hyper-spectral information and whole
Stokes elements spectral from the object on the measuring the power
spectral from the modulator only one time, and that raise the abilityof recognization greatly. The paper carries out a project to the newairborne polarization hyperspectral imager.

8562-9, Session 2

Remote measuring system for infrared
spectral features using hollow fiber probe
Yu-jing He, Yi-Wei SHI, Fudan Univ. (China)
Infrared hollow fibers provide a low-loss transmission media in awide spectral range for active remote measuring system for infrared
spectral features, which core is air or vacuum with simple structure andfabriction, flexibility, and low infrared transmission loss. especially in theinfrared part it has a lower, flat transmission losses, thus, makes infraredtransmission and telemetry possible.
Infrared probes composed of different hollow fibers were designed,
fabricated, and optimized according to their transmission properties.
Remote measuring system using the probe was set up with a Fourier
Transform Infrared Spectrometer (FTIR). Infrared spectral features were
measured for films such as polycarbonate (PC) and Poly vinylidene
fluoride (PVDF), as well as liquid-phase films such as ethanol andtoluene. Quantitative measurements were carried out for the mixed
liquid of ethanol and toluene using the characteristic absorption peakof toluene at the wavenumber of 1605cm-1. The system can be used inremote sensing of spectral features for solid and liquid phase films.

8562-78, Session 2

Design of dual-color ROIC with double
sharing capacitor
Jie Zhou, Rui Jun Ding, Lei Gao, Guo-Qiang Chen, Pan Wang,
Li-Chao Hao, Shanghai Institute of Technical Physics (China)
A readout integrated circuit (ROIC) for 320 x 256 middle-and longwave infrared focal plane arrays is studied in this paper. This circuit
operates in integrating-while-reading (IWR) mode with the frame rate
higher than 100fps. A novel DI structure is used for signal acquisitionof middle wave while BDI structure for long wave. It is common that
trade-offs exist between chip area and performances in integrated
circuits design. In order to getting high injection efficiency for BDI
structure with small area, a four-transistor amplifier with the gain of
82dB is designed here. The charge handling capacity of the integrating
capacitor is also a key performance parameter when considering thenoise and the large middle-wave and long-wave photocurrent (upto 5nA and 100nA, respectively). A structure named double sharing
capacitor (DSC) presented in this paper will be an effective solution togetting a large capacity in the limited 50 um x 50 um pitch area. DSC
means that each sampling capacitor has two kinds of shares. One is
between the sampling capacitor and another sampling capacitor in
the adjacent pixel. The other is between the sampling capacitor andthe holding capacitor in the same pixel. By adopting the 0.35um 1P4M
mixed signal process, the DSC architecture can make the total effective
charge handling capacity as high as 70Me- per pixel with 3V output
swing. According to the simulation result, this circuit works well under
5V power supply and achieves 2.5MHz data transmission rate, morethan 95% linearity. Its total power consumption is 110mW.

8562-10, Session 3

Terahertz supercontinuum generation frommetal foil (Invited Paper)
Cunlin Zhang, Capital Normal Univ. (China)
The interaction of intense ultrashort femtosecond laser with plasma
induced by metal targets can generated high power terahertz (THz)supercontinuum. In our experiment, four kinds of metal foil (Ru, Pt,
Au, and Ti) were pumped by a p-polarized 1kHz, 800nm, ?2.6mJ, and50fs Ti-sapphire laser beam, the intensity of pump laser is below 20W/
cm2, and we can get more than 64?J intense single THz pulse, andthe maximum spectrum was distributed from 0.3 to 149THz which getfrom Ru foil as shown in figure 1. The radiated THz supercontinuums
were obtained by a Michelson interferometer in room temperature. We
found the THz power as a function of thickness of samples, the power
and incident angle of pump laser. Usually, we can get the maximum THz
power from the 200nm-thick foil at about 40°incident angle. In addition,
the THz supercontinuums were broadening when we increased thepump laser power. Finally, we measured the radiated THz energy indifferent direction around sample, and the results show that the THz
emission angular distribution is a typical dipolar emission pattern. We
consider that the THz radiation is generated via the acceleration ofphotoelectron which produced by laser-produced plasma of metal foil
target.

8562-12, Session 3

A scheme format conversion from NRZ-OOK
to QPSK/16QAM signal based on XPM in
SOA-MZI
Yueying Zhan, Min Zhang, Mingtao Liu, Lei Liu, Xue Chen,
Beijing Univ. of Posts and Telecommunications (China)
A scheme of format conversion between OOK signal and opticalquadrature phase shift keying (QPSK)/16-ary quadrature amplitude

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Infrared, Millimeter-Wave, and Terahertz Technologies II
modulation (16QAM) signal based on cross phase modulation(XPM) effect in semiconductor optical amplifiers (SOA) is proposed.
Theoretical analysis and simulations of the format conversion scheme
are conducted to validate the feasibility of the proposal. In this proposal,
When the NRZ-OOK1 data and NRZ-OOK2 data “1” or “0” at the sametime, the gain compression of the SOA is obtained the maximum value
or minimum value, and then the RZ clock pulse signal after passing
through SOA has the phase of”p”or “0” due to the changes of carrier
density. On the other hand, when the NRZ-OOK1 data is “1” while NRZOOK2 data is “0”, and the gain compression is half of the maximum
value, the phase of clock pulse is”p/2”.However, the NRZ-OOK1 data is“0” while NRZ-OOK2 data is “1”, and the phase of clock pulse is”-p/2”.
Therefore, the QPSK signal is converted based on XPM effect in an
SOA. The 16QAM signal can be converted by the superposition of two
QPSK signals which the amplitude of QPSK2 is doubled compared to
QPSK1. The performance and the optimal design of the 10Gbit/s format
conversion system under various key parameters of SOAs are evaluatedand discussed. The receiver sensitivity of the converted QPSK signal
and 16QAM signal after detected is 27.5dBm and -24dBm with BtB at
BER of 10-9, respectively. Simulation results present useful to enableinterconnection between backbone network and access network.

implemented. By considering both terms together, VPPM(Variable
Pulse Position Modulation) modulation scheme is proposed by theIEEE 802.15 standard group. It uses binary PPM (Pulse Position
Modulation) for communication and PWM (Pulse Width Modulation)
for dimming control. In this paper, we introduce the implementation of
VLC demonstration system based on VPPM modulation scheme. Bychanging the pulse width of VPPM signal, we can support 25%, 50%
or 75% dimming. In addition, our VLC demonstration system provides
new power system using solar cell. By receiving the VPPM modulated
visible light signal in the receiver end, we turn on the receiver powerand start system operation to decode the transmitted signal. By using
ATmega128 8bit Micro Controller Unit (MCU) by ATMEL and Cree Q3 of
XLamp XP-E LEDs, our system provides about 2.1kbps data rate with
2.5kHz optical rate in more than 30cm distance. By implementing DM
S/W, we show the bit error rate (BER) and achievable data rate (BER) of
our demonstration system.

8562-13, Session 3

Yu-Ping Yang, Central Univ. for Nationalities (China)

A robust MAP-based method for infrared
image super-resolution
Hui Yu, Huazhong Univ. of Science and Technology (China);
Fusheng Chen, Zhijie Zhang, Huawang Chen, Huazhong
Institute of Electro-Optics-Wuhan National Lab. for
Optoelectronics (China)
Spatial resolution of digital images is limited due to optical/sensor
blurring and detector site density. In many imaging systems, thedetector array is not dense enough to adequately sample the scene
with the desired filed of view. And this is particularly true for infrared
focal plane array. Because of the huge cost of improving the sensor
manufacturing techniques that can directly increase spatial resolution of
infrared imaging system, super-resolution technology is considered asa good approach to obtain high resolution image. Among the available
reconstruction frameworks, the maximum a posterior (MAP) model
based on Bayesian principle is widely used. Motion estimation is thefirst step which is implemented by using image registration algorithm.
The subpixel accurate motion estimation is crucial, otherwise thereconstruction results may be worse than that is obtained by using
interpolation directly. In this paper only pure translational motion isconsidered. Then an approach that can update the image smoothness
is used as the prior knowledge, and the reconstructed HR image will
become blurry; conversely, the noise will not be effectively restrained.
After that, a method based on the U-curve is proposed to choose theregularization parameter adaptively. The reasonable iteration numberof the linear equations extracted from MAP algorithm and the suitable
number of input low-resolution images are also presented in this paper.
The proposed algorithm has been verified using a synthetic infrared
image sequence, and the reconstructed HR images are shown in theend. The experiment results and error analysis show that the proposed
approach is robust and effective.

8562-15, Session 4

Dimmable VLC demonstration systems
based on LED (Invited Paper)
Seongsu Lee, Sung-Yoon Jung, Yeungnam Univ. (Korea,
Republic of)
Recently, there have been many attempts to converge LED with IT
technology. Among them, Visible Light Communication (VLC), which isthe convergence of illumination and communication, has emerged. In
VLC system, both lighting and communication can be simultaneously

8562-16, Session 4

Study of fractional-order surface plasmonsin terahertz frequencies (Invited Paper)
Recently, a new type of extremely sharp resonant lines between thefundamental surface plasmon (SP) modes of a hole array fabricatedon high-resistivity silicon wafers in “optical contact” with thick siliconplates was reported and identified as fractional-order surface plasmons(FSP). However, the physical mechanisms of the FSP resonances has
not been studied more rigorously.
Here, based on the study of a 1D metallic grating, we show
experimentally that the FSP resonances are caused by the gap
reflection of the zero-order and the first-order diffracted beams back to
the 1D or 2D grating, where there is a partial reflection into the forward
zero-order direction, thereby causing the sharp interference peaks
identified as the FSP resonances.
Furthermore, even when the gap is eliminated and the associated
FSP oscillations on the 0-order transmitted pulse disappear, we
shown that two very strong, much delayed, chirped, and long-lasting
pulses are observed after the second reflected pulse. In the frequency
domain, these two strong and fast-ringing structures correspond to the
bandwidth ranges between the [0, 1] and [0, 2] surface plasmon modes
and the range above [0, 2], respectively. A physical optics ray analysis
provides an intuitive understanding of these new four-step (reflection,
diffraction, total reflection, and diffraction) pulses, caused by fractionalorder surface plasmon type beam coupling.

8562-17, Session 4

A photonic approach to microwave/
millimeter-wave frequency measurementwith extended range based on phasemodulation
Xuiyou Han, Nuannuan Shi, Meng Wang, Yiying Gu, Mingshan
Zhao, Dalian Univ. of Technology (China)
The instantaneous frequency measurement (IFM) of the input unknown
microwave signals is critical importance for modern radar warning
receivers in the field of electronic warfare. With the frequencies ofmodern radar systems ranging from sub-gigahertz to millimeter-wave,
the conventional electrical IFM implementations may not meet therequirements of wide operating frequency range and nearly real-time
response. The photonic techniques overcome these limitations due tothe advantages of wide bandwidth, low loss, light weight, and immunity
to electromagnetic interference.
In this paper, a photonic approach to IFM with extended range basedon phase modulation is presented. For the phase modulated microwave
over fiber transmission, the microwave signal can be recovered with the177A  
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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies IIconversion of phase modulation to intensity modulation. The detected
microwave signal power is affected by the microwave frequency, fiber
dispersion and the optical wavelength. In the proposed measurement
system, two optical wavelengths and two segment dispersion fibers
are used to construct the frequency-dependent amplitude comparison
functions (ACFs). Several ACFs can be jointly utilized to determine themicrowave frequency without ambiguities beyond a monotonic regionof the conventional one ACF. Then the measurable range of microwave
frequency can be extended and the resolution can be improved by
selection of ACF with sharp slope. The operation principle of thephotonic approach is illustrated and the preliminary experiment results
show that the frequency from 12 GHz to 18 GHz can be measured
within ±0.2GHz errors. The further research is being conducted and theresults will be presented on the coming conference.

8562-18, Session 4

Signal model and jamming characteristics ofa 35GHz millimeter-wave FMCW SAR
Wen Yu, Beijing Institute of Tracking and Telecommunication
Technology (China)
In the field of airborne remote sensing the combination of compact
frequency-modulated continuous wave (FMCW) technology andsynthetic aperture radar (SAR) paves a way for the development of
the lightweight, cost-effective, high-resolution miniaturized millimeter
imaging radar, which is suitable for small platforms such as unmanned
vehicles(UAV) in military and civil use.
Compared with the conventional pulsed SAR, the continuous platform
motion during the transmission of a sweep and the reception of thecorresponding echo will induce serious Doppler frequency shift as areconstructed image distortion effect. That means, in FMCW SAR, theso-called stop-and-go approximation is no longer valid because of therelatively long sweeps which the FMCW SAR transmits. Based on theanalysis of the signal model, a data processing algorithm by introducing
a new frequency term is proposed to compensate this Doppler shift
in order to complete the imaging process. Through point targets
simulation of a 35GHz millimeter-wave FMCW SAR, the validity of themodel and the efficiency of the processing algorithm are demonstrated
without extra computation load.
As for military use, the technology of FMCW SAR jamming should
always be considered. Regarding of the complexity and the difficultyof FMCW SAR jamming, a novel semi-matching interference solution ispresented in this paper to obtain part of the processing gain after thedechirp-on-receive configuration, resulting in a wide spread spectral
bandwidth and badly degraded resolution. Considering of the FMCWSAR characteristics, several experiments are made to seek significant
jamming conclusions, which is an innovative exploration.

8562-19, Session 5

Spatio-temporal characteristics of global
atmospheric CO2 mole fractions (XCO2)
retrieved from remotely sensed data (Invited
Paper)
Tianxing Wang, Jiancheng Shi, Institute of Remote Sensing
Applications (China); Yingying Jing, Yanhui Xie, Institute ofRemote Sensing Applications,CAS (China)
Carbon dioxide is the most important greenhouse gas produced byhuman activities. Global warming induced by atmospheric CO2 has
attracted more and more attention of researchers all over the world.
Currently, remotely sensed data are frequently used to map theatmospheric CO2 globally. Atmospheric CO2 data retrieved from AIRS,GOSAT, SCIAMACHY over the years of 2009~2011 have been collected
as data sources. Unlike GOSAT and SCIAMACHY, the measurementsof AIRS correspond only to the layer of free troposphere, thus, theReturn to Contents

AIRS CO2 retrievals are first converted to XCO2 by incorporating theCarbon Tracker CO2 profile as well as the averaging kernel of AIRS.
Considering the various spatial and temporal differences of thesesatellite measurements, a matching algorithm has been developed,
so that these different sources of CO2 products can be physicallycomparable in spatial and temporal scales. The times of retrievals of
AIRS and SCIAMACHY are shifted to a uniform reference time (GOSAT
overpass time), and CO2 retrievals with fine spatial resolution are
averaged to produce down-scaled values. Based on the processing
mentioned above, the relationships of these CO2 products and their
spatio-temporal characteristics are then investigated. The results showthat the correlations between them are very weak. Some discrepancies
in global CO2 spatio-temporal characteristics can be detected among
these products. Compared to AIRS XCO2 data, the CO2 spatial
coverage of SCIAMACHY and GOSAT is very limited.

8562-20, Session 5

Development of high efficiency pulse
tube cryocoolers for space-borne infraredapplications (Invited Paper)
Haizheng Dang, Shanghai Institute of Technical Physics (China)
This paper reviews the recent advances in high efficiency pulse tube
cryocoolers (PTCs) in Shanghai Institute of Technical Physics, Chinese
Academy of Sciences (SITP/CAS). The main motivation is to provide
the appropriate active cooling systems with high reliability, low-noiseand long life for space-borne infrared applications. Due to the special
application field where the power supply is relatively limited and therejection condition is extremely adverse, the high efficiency of the PTC
is especially emphasized and thus becomes the research focus. Three
typical geometrical arrangements, U-type, coaxial and in-line, are all
involved, while the latter two are stressed on. To date, the single-stage
PTC covers a wide temperature range from 25 K to 200 K, and thetypical cooling capacities are 4W@60K, 10W@80K and 15W@95K. For
the coaxial PTCs, the typical relative Carnot efficiencies at 60 K, 80 K
and 95 K achieve 9.6%, 14.4% and 17%, respectively. For the highefficiency in-line PTCs, the much higher relative Carnot efficiencies of
17.7% and 19.2% have been achieved at 80 K and 95 K, respectively.
Some typical cryocooler development programs are introduced and abrief overview of the updated data package is presented. The efforts
to realize a good adaptability of the PTCs to the adverse rejection
conditions are also discussed.

8562-21, Session 5

Readout system for the Terahertz
Superconducting Imaging Array (TSIA)
Sheng Li, Jin-Ping Yang, Wen-Ying Duan, Zhen-Hui Lin, Jing Li,
Sheng-Cai Shi, Purple Mountain Observatory (China)
Terahertz Superconducting Imaging Array (TSIA) is a project forthe development of a large THz direct-detection array for mapping
observations. The prototype of the TSIA is an 8x8 pixel direct-detection
array operating at the 850 µm band, incorporating THz superconducting
detectors such as kinetic inductance detectors (KIDs) and transitionedge sensors (TES). KIDs have the advantage that only a broadband
low noise cryogenic amplifier is needed at low temperature for thereadout system, and hundreds of pixels could readout simultaneously
by the frequency-division multiplexing (FDM) technique. The readout
system for a KIDs array is composed of several parts like excitation
signal generating, baseband signal acquisition and processing. The
excitation signal is a kind of comb signal carrying various frequencies
corresponding simply to resonant frequencies of the detectors. It is
generated in baseband with a bandwidth covering all KIDs and upconverted to microwave frequency (about several gigahertz) to feed
the detectors. With THz radiation, the forward transmission coefficient(S21) of all KIDs varies and the variation can be measured through the

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Infrared, Millimeter-Wave, and Terahertz Technologies II
comb signal. Fast Fourier transform spectrometer (FFTS) will be used
to acquire and process the baseband excitation signal in real time.
Consequently, the radiation intensity can be estimated by monitoring
the signal amplitude of the corresponding frequency channels. In thispaper we will present mainly the design of an electronic readout system
for the 8x8 pixel array. Some preliminary experiment results will also begiven.

Mechanics and Electricity (China)

8562-22, Session 5

For argumentation of feasibility of LST retrieval using 8-10 um infraredband, this paper focuses on band design of long-wave infrared
based on theory research. Basis of thermal infrared radiative transfer
and atmospheric simulation, the paper analyses atmospheric effecton different long-wave infrared and obtain a preliminary selectionof potential spectral channels. Several configurations of long-wave
infrared spectral band were selected to perform in Split-Window
algorithm. Then the relation of LST retrieval precision and error source
were analyzed. Several sources of error must be identified to estimate
the total error for LST. We have distinguished three independent error
contributions: the error associated with the split-window method; thetemperature error due to the emissivity uncertainty; and the radiometricnoise error, due to the propagation of the noise equivalent difference oftemperature (NEDT).

Research on the infrared and UV radiation
characteristics of ballistic missile tail-flame
Xiao-hu Liang, Beijing Institute of Tracking and
Telecommunications Technology (China)
During the ballistic missile boost phase, the tail-frame blowing fromthe engine spout generates strong radiation in multiple wave bands,
which is an important information source for the missile detection
and warning. This paper combines the infrared and UV radiationtransmission characters with the ballistic trajectory equation and builds
the infrared and UV radiation transmission models in boost phase. In
ballistic trajectory simulation, we simplify the missile dynamic formulasof the center of mass in boost phase with considering the pitch angle
attitude only, design the flight procedure, and adopt the aerodynamic
coefficients of “Titan-II” to generate the simulation trajectory using
fourth-order Runge-Kutta method. When forming the tail-flame
radiation transmission formula, the off-nose angle and the atmospheretransmittance varying with the altitude and wave length are taken into
consideration. This paper analyzes the effect on radiation transmissionof these factors such as sensor position, missile altitude, missile body
attitude, detection wave band and atmosphere attenuation, then gains
the received radiation intensity and its time-variant character. The
result provides a theoretic foundation for choosing sensor platformand detection wave band. Based on the above working, the infraredand UV background radiation intensity at the sensor is analyzed tocompute the received radiation SNR, which gives limits on the sensor
sensitivity and the detection capability of weak signal. The results showthat the motion character of the missile has different effect in different
wave bands and the UV detection can give an earlier warning than theinfrared.

8562-23, Session 5

Goos-Hänchen shifts on the air-COC
interface in the terahertz region
He Jun, Qingmei Li, Capital Normal Univ. (China)
Transmission properties of terahertz pulses through Asymmetric double
split-ring resonators
We demonstrate narrow transmission resonances at THz wavelengths
utilizing coupled asymmetric split-ring resonators (SRRs). By breaking
the symmetry of the coupled SRR system, one can excite dark resonantmodes that are not readily accessible to symmetric SRR structures.
Besides, increasing the length of the sides parallel to the polarizationof the incident terahertz wave, the resonant frequencies are observed
to red shifting. This theoretical simulation will be good reference for thefollowing experience, and these asymmetric metamaterials will promote
new avenues to the control of terahertz waves.

8562-37, Poster Session

Rational design of long-wave infrared
band for application of the earth surface
temperature observation
Yunfei Bao, Hongyan He, Feng Zhou, Beijing Institute of SpaceThe land surface temperature (LST) is very important in determining
net radiation, evaportranspiration, and energy balance at the Earth’s
surface and assessing the status of crops and soils. LST estimationneeds to take into account the nonblackness of natural surfaces,
their heterogeneity at satellite pixel scale and disturbing effects
introduced by the atmosphere. Rational band configuration and sensor
performance requirements must also be determined.

The analytical results show that the temperature error from split-window
algorithm using 10-12.5um is about ±0.89 K, while the temperatureerror using 8-10 um is about ±1.13 K. So the results indicate thescheme of LST retrieval using 8-10 um long-wave infrared is feasibility
in scope of needed retrieval precision.

8562-38, Poster Session

The research of remote sensing duststorm
with FY-3B three infrared channels
Hui Xu, Tao Yu, Donghai Xie, Jiaguo Li, Institute of Remote
Sensing Applications (China); Jibao Lai, State Key Laboratoryof Remote Sensing Science,Institute of Remote Sensing
Applications (China)
Dust aerosol extinction characteristic shows a signiﬁcant diurnal cycle
which can be used to monitor the dust intensity information. Basedon the new generation meteorological satellite of FengYun, this paper
proposed a bi-temporal method of remote sensing dust aerosol with
infrared channels. Firstly, the dust aerosol extinction diurnal cycle
characteristic is discussed within the Infrared spectral range. Secondly,
based on the infrared spectral variations difference of dust aerosol,
land surface and cloud, the dust aerosol identification method wasinvestigated by this paper. Thirdly, by using the characteristics ofinfrared extinction and diurnal cycle of dust aerosol, a bi-temporal
thermal dust index (BTDI) which can be used to represent the
information of dust intensity is derived from the new generation
meteorological satellite of FengYun 3B infrared channels(10.8?m and12?m) at two different time slots during a day. At last, three months(March to May 2011) BTDI values are evaluated with the corresponding
Aerosol Robotic Network (AERONET) data and the result shows that 1.
BTDI shows a negative correlation with aerosol optical depth which canwell reflect the dust aerosol intensity. 2. BTDI is sensitive to dust aerosol
and it will decreases rapidly with the aerosol optical depth increase.

8562-39, Poster Session

Role of soft-collision in terahertz generationin ionizing atoms
Dongwen Zhang, Zhihui Lv, Chao Meng, Zhaoyan Zhou,
Zengxiu Zhao, Jianmin Yuan, National Univ. of Defense
Technology (China)
We perform a joint measurement by monitoring THz and high-order

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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies II
harmonic yields in a two-color laser field simultaneously. By correlating
their phase-delay dependence, the absolute relative phase dependenceof THz yields can be retrieved and it is found that THz yields takemaximum at phase delay of 0.8 deviated from the prediction of previous
models. By analyzing electron dynamics classically and quantum
mechanically, we find that the Coulomb potential of the residual ion
can not be neglected. It is shown that laser-assisted soft-collisions of
the electronic wave packet with the atomic core induces momentum
transfer to the electron affecting the phase dependence of THz yields.
The joint measurement of THz and harmonic yields allows us todetermine the generation of THz waves in attosecond precision. We
show that the hard-collision with the atomic core causes HHG uponrecombination, and the soft collision with the atomic core gives rise
to THz photocurrents. We expect that the sensitivity of THz yields on
Coulomb potential could be used to map atomic fields from within andhelp the full characterization of the rescattering wave packet, beyond
the recombination in HHG and back-scattering in ATI.

In this paper, to reduce the fringe NU in uncooled VOx IRFPA we
present a simple and effective SBNUC method based on ConstantStatistics in which the fringe NU is reduced by balancing the statisticsof the vertical channels. Through analyzing the reason of ghost artifact
being brought in in the SBNUC algorithms, our algorithm successfully
reduce the ghost artifact that plagues SBNUC algorithms throughthe use of optimization techniques in the parameter estimation .The
advantage of the algorithm lies in its simplicity and low computational
complexity. Our algorithm is implemented on a FPGA hardware platform
with XC5VSX50T as the kernel processor, the raw infrared data areprovided by an uncooled infrared focal plane array of VOx which has
fringe NU. Our processing system reaches high correction levels, fringe
NU being reduced, the ghost artifact being decreased , which can lay
a technical foundation for the following study and applications of highperformance thermal imaging system.

8562-40, Poster Session

High-power terahertz quantum cascade
laser

Single-scan coherent detection withenhanced time resolution for arbitrarily
polarized terahertz wave
Zhihui Lv, Zengxiu Zhao, Jianmin Yuan, National Univ. of
Defense Technology (China)
The technology of terahertz wave air-biased-coherent-detection(THz-ABCD) using gases as the nonlinear media and utilizes thethird-order optical nonlinearities and leading a broad bandwidth fully
covering the terahertz gap, has been widely used in THz applications.
Utilizing the centrosymmetry of gases, we had reported a scheme ofpolarization-sensitive THz -ABCD. It directly measures the amplitude
and polarization angle of the THz filed and provides a same detection
bandwidth as the conventional method.
Here we present an enhanced scheme of polarization-sensitive THzABCD which can provide about twice broader bandwidth than theconventional method. It uses a probe beam which is modulated intime domain. In our experiment using a 26 fs laser pulse, comparedwith 0.3~40 THz in conventional scheme, bandwidth coverage from
0.3 to 80 THz has been achieved. It also should have to be noted theterahertz source may also restrict the detection bandwidth. On theother hand, this scheme is also polarization-sensitive. The polarization
angle in time domain, as well as the field amplitude, can be achieved
with just one single scan. It is expected to reach a high time resolutionof few femtoseconds if few cycle laser pulse is employed. The signalnoise-ratio (SNR), however, is much less than that of the conventional
method. Several suggestions to improve the SNR have also been
indicted in the paper.

8562-41, Poster Session

SBNUC based on constant statistics for VOx
uncooled IRFPA and implementation with
FPGA
Shudi Wei, Weiqi Jin, Minglei Jin, Chao Xu, Beijing Institute ofTechnology (China)
The quality of infrared imaging system was limited by thenonuniformity?NU?in the Infrared Focal Plane Array(IRFPA), especiallyin the uncooled infrared imaging system. Scene based nonuniformity
correction?SBNUC?algorithms are widely concerned since they only
need the readout infrared data captured by the imaging system during
its normal operation. However, there still exists the problem of ghost
artifact in the algorithms, and their performance is noticeably degradedwhen the methods are applied over scenes with lack of motion. In
addition, most SBNUC algorithms are difficult to be implemented in the
hardware.

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8562-42, Poster Session

Jianyan Chen, Junqi Liu, Tao Wang, Fengqi Liu, Zhanguo Wang,
Institute of Semiconductors (China)
In recent years, the terahertz (THz) frequency range (0.1 THz~10 THz)has been concerned because of its great potential applications. With
the development of terahertz technique, the “terahertz gap”, formed
due to the lack of suitable sources to generate steady radiation, hasbeen gradually filled up. However, high-power THz radiation sources
are still much desired. Among the various methods of generating
coherent THz radiation, quantum cascade laser (QCL) as compact andconvenient device is the most promising candidate due to its novel
operation principle and attainable performance. Up to now, spectral
coverage has been demonstrated from 1.2–5.0 THz (when operated
without the assistance of external magnetic field). However, theiroperation temperature is still limited in the cryogenic range, leading toconsiderable interest to raise it into thermoelectric coolers’ range. At
the same time, higher output power is always another most importantresearch goal. High power operation based on resonant-phonon(RP) active region design has been reported. However, consideredfault-tolerant space when grown by molecular bean epitaxy (MBE),
the bound-to-continuum (BTC) structure is much robust than the RP
structures.
In this work, we presented high power THz QCL at about 3 THz basedon BTC active region design. At 10 K, corrected by the collection
efficiency, the maximum peak power of 137 mW was obtained in pulsed
mode. What’s more, we firstly introduce monolithically integrated THz
QCL array and the maximum peak power of two-device-array increased
to 218 mW. In total, the array improves the performance efficiently,
implying cheerful prospect.

8562-44, Poster Session

A target recognition method for totalreflection terahertz scanning images
Yuan-meng Zhao, Chao Deng, Xin Zhang, Cunlin Zhang, Capital
Normal Univ. (China)
The THz region occupies the part of the electromagnetic spectrum
between 30?m and 3 mm. THz radiation, which is a form of low level
energy naturally emitted from all materials such as rocks, animals andpeople, doesn’t involve any of the harmful radiation like the traditional
X-ray. Due to this characteristic, since last two decades, there has
been an increased interest in THz imaging for security applications, touncover concealed weapons, dangerous materials or illegal products on
person. Two imaging approaches associated with this technology are
active imaging method and passive imaging method. Passive imaging
method, without the use of an external illuminator, has the advantageof achieving a good balance between security and civil liberties. Our

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Infrared, Millimeter-Wave, and Terahertz Technologies IIwork focuses on studying the passive imaging method. From ourprevious work, we developed a set of passive THz security screening
system and got some initial THz scanning images, however, the target
recognition ability of the system still needs to be improved. Therefore,
the purpose of this paper is to develop an image processing method
used in this system for improving the system’s target recognition
ability. The image processing method includes the following steps.
First, the vertical stripes caused by the scanning pattern are filtered byusing a variety of masks through methods such as smoothing filteringand median filtering, so that we improve the uniformity of the image.
Second, we perform the image interpolation and image sharpening.
Third, the person is segmented from the image using the Otsu method,
and then we draw the contour outline of the person by means ofcomputing the gradient image. Fourth, the study adopts the watershedalgorithm to segment the image region where the possible concealed
targets are located. Finally, we optimize the display effect of the target
areas by using the pseudo-color enhancement method, image fusion
method which involves using a registered visible image, and describing
the edges of person and targets through a virtual image. Both thesimulation experiment results and the actual system performing results
demonstrate the efficacy of our methods. The resulting images canclearly distinguish the human body’s edge from the background anddisplay the position of the possible concealed targets. In addition, theshape of the targets can be recognized to a certain extent. We can draw
a conclusion that the method introduced in this paper has the capability
to help the checkpoint security staff easily detect the concealed targets
on person remotely. In the end, we discuss the future research direction
which will be to further improve the image resolution.

8562-45, Poster Session

Terahertz spectroscopic investigation ofpolypeptide and protein

8562-46, Poster Session

Target detection method based on multi-life
restrict used in super wide angle infrared
starting warning system
Bing Zhou, Fuyu Huang, Jia-ju Ying, Shijiazhuang MechanicalEngineering College (China)
As early as possible discovers the enemy target is the key that seizes
the information advantage in the modern war. But the threat present anomni-directional property for the high-tech weapon is applied largelyin the modern war, therefore require infrared reconnaissance andwarning system to have omni-directional reconnaissance ability. So,
the developed country makes greatest efforts to pursue the omnidirectional staring electro-optical equipment since the beginning of 90’s
in last century and make progress continuously. In recent years, infrared
equipment with super big field angle appears gradually. In recent years,
super angel infrared lens with field angel achieve 135°and 180°appears
already, and super airspace staring reconnaissance system based onthem being practical gradually.
A moving target will appear as with up-and- down gray scale insequence images of fish-eye staring system for its sub-pixel imaging
attribute. This bring difficult to track correlation for the target’s time
pertinence reduce too. In allusion to up special problem, put forward
adopt nearest correlation method firstly. Add dummy target in tracking
maintain process treating the track cross. Endue target multiple life,
such as accumulate life in history, per-pixel life and average life, treating
the temporary disappearance when target move between pixels. All
those method effectually solve the special problem of target time grayscale in fish-eye staring system. Discuss some problems of target trackcorrelation based on sequence images in this kind system. Such as
target point register, new target process, nearest correlating process,determine track disappear, track maintain process, and so on.

Xiu-Hua Fu, China Jiliang Univ. (China)
With the development of biotechnology, peptides and protein as
drugs in clinical become more and more widely. Polypeptide oxytocin,
eptifibatide and protein bovine serum albumin and collagen are largebimolecular which had poor stability compared to traditional small
molecular of organic medicine. Analysis in their stability of temperature,dehydration, hydration or binding from simple or quickly methods isvery important.
In this study, we used terahertz time-domain spectroscopy (THz-TDS)
to measure oxytocin, eptifibatide, bovine serum albumin and collagen,and obtained absorption and the refractive spectra of native or heatedstate in 0.2-1.4THz region at room temperature. The results showedthat polypeptide and protein both have strong absorption, but theircharacteristics were not distinctly, heated protein or polypeptide
compared to unheated have distinct difference from each other fromabsorption spectra, the absorption decreased in heated state. We
used Debye model simulated terahertz dielectric spectra of protein
or peptide. Experimental results were in good agreement with thesimulation. We obtained the Beta relaxation time of different states
and conformation changed relaxation time, they had distinct changes
in heated. Due to the decrease water in surface layer of protein during
thermal, the absorption decreased. The protein of heated had distinct
changes compared to small molecules in relaxation time, especially, thehigh energy of protein. The results proved that the terahertz spectrum
technology is feasible in testing protein and peptide that were affectedby temperature, which can provide theoretical foundation in thefurther study about the THz dielectric spectrum of protein and peptide
temperature stability

8562-47, Poster Session

Performance of portable high-resolution
Fourier transform spectrometer for trace gas
remote sensing
Haoyun Wei, Tsinghua Univ. (China); Dongdong Fan, Beijing
Vision Sky Aerospace Technology Co., Ltd. (China); Marc-André
Soucy, ABB Analytical Measurement (Canada)
The perturbations of atmospheric composition due to industrial
emission, volcanic eruptions and biomass burning are changing theenvironment and the climax. Observations of these perturbations in
the Earth’s atmosphere are important in the study of atmosphericchemistry and in the development of models that can predict thepossible evolution of this complicated system. Though the conventional
sampling measurements provide direct and precise results, the remotesensing measurements using the atmospheric absorption spectrum
have advantages in risk-free and long-term monitoring. Fourier
Transform Spectrometer (FTS), with its throughput, multiplex, andspectra resolution advantages, has been deployed on various satellites
and planetary probes, on balloon gondolas, and on the ground foratmospheric remote sensing. Especially, remote sensing from a satellite
platform such as the Atmospheric Chemistry Experiment (ACE) FTS on
the SciSat-1, the Infrared Atmospheric Sounding Interferometer (IASI)
on the METOP and the Thermal And Near infrared Sensor for carbon
Observations (TANSO) on GOSAT can provide a global picture ofchanges in the atmospheric composition.
In this paper, the concept and performance of a portable high resolution
FTS bread board model is reported. With its wide spectral coverage(800cm-1~4000cm-1), high spectral resolution (0.028cm-1), and high
SNR(>100:1@atmospheric windows), It is very suitable for atmosphericabsorption spectra detection using solar as light source. Some design
considerations of the reported FTS are introduced, and its performance,such as the Instrumental Line shape (ILS) and Signal to Noise Ratio

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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies II(SNR) are tested. Using the calibrated measurement spectra, total
column value of several trace gases are retrieved and discussed.

8562-48, Poster Session

Continuous field measurements of [delta]
D in water vapor by open-path Fouriertransform infrared spectrometry
Wei Wang, university of Science and Technology of China(China) and Anhui Institute of Optics and Fine Mechanics(China); Wenqing Liu, Tianshu Zhang, Anhui Institute of Optics
and Fine Mechanics (China)
The measurement of stable isotopes has emerged as a very important
tool to understand ecosystem-atmosphere gas exchange and its rolein the carbon and hydrologic cycles. The paper describes a seven day
field experiment in which an open-path FTIR system was employed
to measure the isotope composition of H2O and CO2 in ambient
air continuously. Mixing ratios of12CO2, 13CO2, H16OH and HDO
were measured simultaneously. We used a three-dimensional sonicanemometer and a temperature and humidity sensor to observe
meteorological conditions concurrent with the FTIR measurement. The
results suggested that the variations of 12CO2 and 13CO2 were highly
correlated, with a obvious diurnal pattern. It was unexpected that timeseries of del13C showed no linear relationship with the variations ofcarbon dioxide, which was confirmed by the subsequent Keeling plot
analysis. The complex geographical environment of the measurementsite was likely to make the Keeling assumption break down. On theother hand, the outcomes of H2O and its isotopes revealed that thevariations of H16OH and HDO were also strongly related, both showing
a clear diurnal cycle. In this case, although the Keeling assumption
appeared to be not well met for the data, the linear relationship between
the total mixing ratio H2O and isotopic composition of existed. Theintercept of the linear regression line gave the deuterium isotopic ratioof evapotranspiration source, which is -110.6±4.3‰. The experimentresults exhibited the suitability of the open-path FTIR system to longterm and in-situ measurement of isotopes in CO2 and H2O.

8562-49, Poster Session

10Gbit/s full-duplex bidirectional RSOAbased WDM PON using Mach-Zehnderinterferometer and forward error correction
Weiping Han, Min Zhang, Mingtao Liu, Beijing Univ. of Posts
and Telecommunications (China)
In this paper, a 10Gbit/s full-duplex bidirectional WDM PON with
RSOA-based colorless ONUs has been designed and demonstrated,which uses Mach-Zehnder Interferometer (MZI) as optical equalizer
and applies Forward Error Correction (FEC) to correct burst errors. An
effective 10Gbit/s parallel algorithm is designed and implemented torealize the FEC module. DPSK and NRZ are used in the downlink anduplink to reduce the interference. First, we confirm that RS (255,223)
decoder is capable of correcting up to at most 16 symbol-errors or
128 continuous bit-errors in a block codeword based on the parity
information. Second, we use CW signal in the downstream to drive
RSOA with the upstream NRZ signal to test and verify the optical filter
capability of MZI which acts as a two-tap optical equalizer in uplinktransmission. The measured results show that the received sensitivityof ~-21.46dBm is obtained with MZI which is about 2dB lower thanthat without MZI. Lastly, we demonstrate that the fiber length has little
impact on the downstream DPSK signal within a range of no longer than
20km. The BER cannot achieve the RS (255,223) threshold whether
after 10km or 20km SMF transmission without MZI in the upstream.
The received sensitivity of ~-25.2dBm@BER=2.4?10-3 is obtainedin downstream and a better received sensitivity of ~-12.68dBm@
BER=2.5?10-3 is obtained with MZI. In addition, the received sensitivity

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could increase by nearly 5dB by using RS (255, 223) code.

8562-50, Poster Session

An experimental 0.2 THz stepped frequency
radar system for the target detection
Bangze Zeng, Meiyan Liang, Yuejin Zhao, Beijing Institute ofTechnology (China); Cunlin Zhang, Capital Normal Univ. (China)
Compared with traditional microwave and millimeter wave radars,
Terahertz radar has wide signal bandwidth and a very narrow antennabeam, which is beneficial to the realization of high resolution imaging.
And as an instantaneous narrowband and synthetic wideband
waveform, stepped frequency radar signal has been widely exploited
in many applications, since it allows high range resolution withmodest requirements of the system bandwidth. As an instantaneous
narrowband and synthetic wideband waveform, stepped frequency
radar signal has been widely exploited in many applications, since itallows high range resolution with modest requirements of the system
bandwidth. This paper presents the design of a 0.2THz steppedfrequency imaging radar system with operating bandwidth of 12 GHz,
thus, a theoretical range resolution below 1.25 cm. The simulation of
the system is implemented by using system design parameters. An
experimental trial has been performed, and one-dimensional range
profile of the stationary target is obtained by imaging experiment using
THz radar. Results show that the THz radar imaging system could
achieve the target detection and centimeter-level range resolution.

8562-51, Poster Session

A reflection sensor based on the Rayleighanomaly of metallic grating in terahertz wave
band
Lingyue Yue, Capital Normal Univ. (China); Jingwen He,
Shengfei Feng, Xinke Wang, Wenfeng Sun, Yan Zhang, Capital
Normal Univ. (China) and Beijing Key Lab. for Terahertz
Spectroscopy and Imaging (China) and Key Lab. of Terahertz
Optoelectronics, Ministry of Education (China)
An optical refractive index sensor based on the Rayleigh anomaly ofgold grating is demonstrated in terahertz wave band. A pronounced
peak due to the Rayleigh anomaly of the gold grating is observed in
the reflection spectrum, the center wavelength of which is sensitive
to the change in the environmental refractive index on top of thegrating. The wavelength of the Rayleigh anomaly reflection peak andthe corresponding sensitivity are solely determined by the period of
the gold grating, the larger of the period, the longer of the wavelengthand the higher of the sensitivity. Therefore, higher sensitivity can beachieved in terahertz wave band. Both theoretical and experimental
investigations show that the shape and intensity of the Rayleighanomaly reflection peaks are determined by the duty cycle of thegrating, for the value of the duty cycle about 0.4, the maximum intensityof the Rayleigh anomaly reflection peak was achieved.

8562-52, Poster Session

A novel target LOS calibration method for IR
scanning sensor based on control points
Yong-Hong Xue, Wei An, National Univ. of Defense Technology(China); Yin-Sheng Zhang, Tao Zhang, Beijing Institute ofTracking and Telecommunication Technology (China)
Space based IR system uses the information of target LOS (line ofsight) for target location. Recent researches show that the measuring
precision of target LOS is usually determined by measuring precision

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Infrared, Millimeter-Wave, and Terahertz Technologies IIof platform’s position and attitude, and deformation of sensor etc.
Most methods for improving target location precision are either throughimproving platform’s position and attitude measuring precision or
through calibrating the whole image obtained by IR sensor. With thedevelopment of measuring technology, it is harder to make a further
improvement through measurement of position and attitude of theplatform, and the expansion of the sensor view make calibration of thewhole image with a larger computation cost. In this paper, a method
using control points to calibrate target LOS was proposed. Based on
the analysis of the imaging process of scanning sensor of space based
IR system, this paper established a modify model of target LOS basedon control points, used a bias filter to estimate the bias value of sensor
boresight, and finally achieved the mission of target LOS calibration.
Different from the traditional calibration method of remote sesnsing
image, the proposed method only made a correction on the LOS of
suspicious target, but not established the accurate relationship between
the all pixels and their real location, and has a similar calibration
performance, but much more lower computational complexity.

8562-53, Poster Session

Numerical simulation of terahertz
transmission of bilayer metallic meshes withdifferent thickness of substrates
Guozhong Zhao, Capital Normal Univ. (China)
The terahertz transmission characteristics of bilayer metallic meshfilters with the different thickness of substrates are studied based on
the finite difference time domain method. The well-shaped grid, thearray of complementary square metallic pill and the cross wire-hole
array were investigated. The numerical results show that the wellshaped grid have the function of a high-pass filter, while the square
metallic pill array show the function of a low-pass filter, and the crosswire-hole array can be used as a band-pass filter. The substrate fills
in the gap between two metallic microstructures. The material andmedium thicknesses of substrates have an influence on the terahertz
transmission characteristics of metallic microstructures. The simulation
results show that the cut-off frequency of high-pass filter and low-passfilter move to low frequency with increasing the thicknesses of medium.
The bilayer cross wire-hole array shows two transmission peaks whichhave the competition effect.

8562-54, Poster Session

Uncooled infrared imaging system based on
the filter method with polka-dot beamsplitter
Lin Ding, Beijing Institute of Space Mechanics and Electricity(China); Mei Hui, Beijing Institute of Technology (China); Yiliang
Liu, Beijing Institute of Space Mechanics and Electricity (China);
Wenjuan Wang, Yuejin Zhao, Beijing Institute of Technology(China)With the popularization and ripeness of uncooled infrared MEMS
system, its advantages such as low-cost, no refrigeration equipment
and more reliability have emerged. Compared with electrical method,the optical readout method has advantages like simpler preparation,higher sensitivity. The common filtering methods adopt knife edge andsmall aperture in the 4f system. However, these methods make therealizing miniaturization system more difficult, and can’t remove thebackground noise effectively. A new filtering method is presented in thispaper, this method use Polka-Dot Beam splitter instead of knife edge
and small aperture to modulate the incident light.
The Polka-Dot beam splitter filter as a novel kind of spectral component
is chosen in this method. The characteristic of this filter is that its
coated-to-uncoated surface area has a “polka-dot” type appearance.
Incident light can be reflected by the coated area and transmitted
through the glass. Therefore the Polka-Dot beam splitter can modulate

the amplitude of incident light for its special structure. The Polka-Dot
Beam splitter filter can improve the signal noise ratio (SNA), raise thedetection sensitivity and simplify the structure. From the theoreticalanalysis and experimental results in this paper is can be concluded thatthe novel method have more advantages compared with the traditional
filtering methods.

8562-55, Poster Session

Denoising to the pulsed laser radar return
waves based on pulses accumulation andwavelet filter
Xiping Cai, Jianbo Liu, Heilongjiang Univ. (China); Quan
Han, Harbin Institute of Technology (China); Wenjiang Dai,
Heilongjiang Univ. (China)
Ladar (Laser Radar) is a radar which commonly utilizes the FMCW
(Frequency Modulation Continuous Wave) waves or narrow pulses as
the modulation regime. Based on the captured return waves, ranges
to the target and other information such as characteristic of the target,
intensity image, range image and 3D (three dimensional) image of thetarget may all be obtained. There are many factors which may affectthe performance of a laser radar, these include the rationality of thetransmitting and receiving optics design, the absorption and scatteringof the atmospheric particles to laser, atmospheric turbulence, target’s
characteristics, signal processing utilized, etc. The method based on
advanced signal processing may be applied to increase the signalto-noise ratio for laser radars. In order to improve the performanceof a pulsed laser radar, methods based on wavelet filter and pulses
accumulation are investigated. The transmitted pulses and received
return waves are modeled for the simulation of signal processing
through a filter. It shows that the modeled return waves could bedenoised effectively with the wavelet biro3.9 or db9 if it is on thebasis of compulsory denoising. However, under the condition of highfidelity requirement for the waveform, the signal-to-noise ratio may not
be increased considerably. Thus, a new filter which is based on the
combination of pulses accumulation and a followed wavelet transformer
is proposed and studied. The results show that it is preferable toincrease the signal-to-noise ratio than any of the two single filters, i.e.
pulses accumulation filter and wavelet filter.

8562-57, Poster Session

Measurement and analysis of perceivablesignal-to-noise ratio for infrared imaging
system with human vision
Xin Liu, Jing Zhao, Honghua Chang, Lin Ma, Xidian Univ. (China)
The perceivable signal-to-noise ratio (SNR) is the basis of performance
theoretical model of an infrared imaging system (IRIS) with humanvision. The existing triangle orientation discrimination (TOD)
performance model assumes that a constant SNR threshold is achievedat some point in the visual processing chain for a detection to occur,
which may cause error in the results. In order to improve the precisionof the model, we need to obtain the perceivable SNR thresholds
changed with the correct discrimination probability of the human eye.
In this paper, the relationship between correct discrimination probabilityof the human eye and perceivable SNR threshold is studied for different
equilateral triangle sizes with specified luminance through combining
theoretical calculation with practical experiment. Firstly, the simulation
images of triangle patterns with different sizes and thermal contrasts
are generated by an IRIS simulation model. System noises and somephysical effects are added to each image. Then the perceivable SNRs
for these images are calculated by establishing the system theoreticalmodel and the human vision system model. At the same time, thecorrect probabilities with which the triangle orientation of each test
images is just judged are obtained by Four-Alternative Forced-Choice

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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies IIexperiment. Finally, the curves of correct discrimination probabilities
changed with perceivable SNRs are fitted for different triangle sizes
with specified luminance. The analyses of these results show that thesechanges are accorded with the psychometric function and the fitting
curves become steep with the increasing of triangle size. These dataand conclusions are helpful to modify the existing TOD performancemodel of an IRIS.

8562-58, Poster Session

An 8K FFT architecture for FPGA-based
space-borne FTS on-board data processing

geometries are expected to present unique plasmonic properties thatwere not observed at higher frequencies. In addition, the advantage of
exploring such subwavelength structures at terahertz frequencies is thatthe well-developed lithographic processing allows for precise control
over the dimensions of the microstructured bowtie unit cells, whichenables systematic and highly reproducible studies of their resonant
properties.
Here, in order to provide a guide for the design and optimization of
bowtie antennas, their plasmonic properties have been experimentallyinvestigated with emphasis on geometry and gap separation in THz
frequencies. Based on numerical simulations, we find that absorbing
properties of the periodic bow-tie particles in the terahertz regime are
primarily associated with the shape, curvature, gap separation of the
bow-tie unit cells.

Jiaqing Liu, Shanghai Institute of Technical Physics (China)
In-place compution,regularity and parallel FFT algorithms is better foron board data processing with limited resource.To meet 8K or near
points of Interferogram inverse fourier transform within 1ms of on board
processing requiment.A 8K parallel FFT architecture for FPGA-basedis proposed in this paper,which is based on Singleton’s parallel FFT
algorithm.It contains 8 radix-2 butterflies in parallel and 16 complex
data FIFOs to store the input and use as memory storage between
stages.

8562-60, Poster Session

Using Singleton’s single butterfly method,the calculated latency for a
8K-point FFT is 26624 cycles.With 8 butterflies parallel,the calculated
latency is 6656 cycles.The number of butterflies can be changed to fulfil
different calculated latency.

We propose two simple solutions to generate power efficient UWB
waveforms employing an electrical bandpass filter (EBPF) and a fiber
link. The fiber link is used to transmit the optical signal in opticaldomain, and the electrical filter is used to process and generate UWB
waveforms. In the first scheme, the arbitrary waveform with enoughbandwidth (>10GHz) is converted to power-efficient electrical UWB
signal by an EBPF with a passband of 3.1-10.6 GHz, and then intensity
modulated onto an optical carrier to form an optical UWB signal, which
can be distributed by a fiber link and received by a photodetector (PD).
The second scheme is transmitting the optical Gaussian pulse in opticalfiber link and received by a PD. Finally the received electrical signal
is converted to an electrical UWB pulse by the EPBF. These solutions
embody the advantages of both low-loss long-haul transmission of
optical fiber and low-cost mature RF circuits.

The main function blocks of the 8K parallel FFT Hardware Architecture
are : the 8 radix-2 butterflies structure,the 16 FIFOs for the real
inputs,the 16 FIFOs for the imaginary inputs,the complex twiddle factor
memory storage, the logic controller,and the bit reverse order unit.
The radix-2 butterfly based on DSP48E blocks,to improve calculated
latency.
The resource utilization of the 8K FFT is shown below.The Xilinx
XC5VFX130T is given for comparison(not implenment in it):Resource Usage XC5VFX130T %Power-efficient UWB generation based on
hybrid of optical fiber link and RF circuits
Jianji Dong, Xinliang Zhang, Dexiu Huang, Yu Yu, Huazhong
Univ. of Science and Technology (China)

Slices 6812 17280 7.54
DSP48E 32 320 10
BRAMs 32 298 10.7
The 8K parallel FFT has a total latency of 416us while operating at a
16MHz clock which meets the latency requirement of 1ms.
It could have several 8K FFT blocks in one FPGA,which means several
Interferograms can processing parallel at the same time,which is useful
for FTS on board processing.
Change the numbers of butterflies,The architecture could have a trade
between calculated latency and resource usage.

8562-59, Poster Session

Plasmonic resonance of bowtie antennas
and their geometry dependence
Yu-Ping Yang, Minzu Univ. of China (China); Ruilin Dong, Minzu
Univ. of Chian (China); Yixuan Nie, shang yao, Yucheng Jiang,
Jing Meng, Minzu University of Chian (China)
Recently, metallic bowtie antennas has attracted increasing attention
because the optical field between two bowtie tips can be enhanced
tremendously by the plasmonic resonance and curvature effect ofbowtie tips. Studies have shown that the strong field confinement
provides a higher spatial resolution and more efficient excitationin the subwavelength-scale regime, which are useful for a variety
of applications, such as the surface enhanced Raman scattering,high-density optical storage, and near-field imaging. With extensively
increased conductivity of metals in the terahertz regime, the bowtie

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8562-63, Poster Session

An image processing system design in a new
type of infrared imaging technology basedon MEMS
Qiang Tong, Liquan Dong, Yuejin Zhao, Cheng Gong, Lei Yang,
Beijing Institute of Technology (China)
Compared with the traditional infrared imaging technology, the new
type of optical-readout uncooled infrared imaging technology based on
MEMS has many advantages, such as low cost, small size, producing
simple. In addition to, the theory proves that the technology’s highthermal detection sensitivity. So it has a very broad application
prospects in the field of high performance infrared detection. The paper
mainly focuses on an image capturing and processing system in the
new type of optical-readout uncooled infrared imaging technology
based on MEMS. The image capturing and processing system consistsof software and hardware. We build our image processing core
hardware platform based on TI’s high performance DSP chip which is
the TMS320DM642, and then design our image capturing board basedon the MT9P031. MT9P031 is Micron’s company high frame rate, lowpower consumption CMOS chip. Last we use Intel’s company networktransceiver devices-LXT971A to design the network output board. The
software system is built on the real-time operating system DSP/BIOS.
We design our video capture driver program based on TI’s class-mini
driver and network output program based on the NDK kit for image
capturing and processing and transmitting. The experiment showsthat the system has the advantages of high capturing resolution andfast processing speed. The speed of the network transmission is up to
100Mbps.

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8562-64, Poster Session

8562-66, Poster Session

A reflective optical readout method based on
the infrared imaging system

Infrared and color visible image fusion
system based on luminance-contrast
transfer techniqueWenjuan Wang, Mei Hui, Cheng Gong, Liquan Dong, Xiaohua
Liu, Yuejin Zhao, Beijing Institute of Technology (China)
The uncooled optical readout infrared imaging system to alter the
infrared image directly into a visible image is becoming a hotspot of
research recent years. How to reduce the volume and NETD value isa key problem of the optical readout infrared thermal imaging system.
In this paper, an effective optical readout method of infrared imaging
systems is presented. This method is proposed to design the opticalreadout system to reflection optical path, and a reflected filter whichis complement with traditional filter is used in this method. First, theworking principle of this system is described in detail, and length ofreadout system is calculated. Then the analysis of the characteristics
and the working principle of the reflection filter is revealed in this paper.
Finally, contrasting experiments have been carried out on reflective
filter method and pin-hole filter method, experimental validation ofthis system is undergone and the feasibility of the system is proved,and NETD value of the system is obtained. Compared with traditional
methods, the effective optical readout method could reduce the volumeof the system, improve the uniformity of the infrared image, reduce thenoise equivalent temperature difference, and improve the detective
sensitivity of the infrared imaging systems. The result of experiment isbasically consistent with the theory analysis. Compared with traditional
pin-hole method, the reflective optical readout method can effectively
improve image quality.

8562-65, Poster Session

Optimal design of high frequency readout IC
for short-wave IRFPA
Pan Wang, Guo-qiang Chen, Lei Gao, Jie Zhou, Rui-jun Ding,
Shanghai Institute of Technical Physics (China)
A novel design of high frequency and low signal ROIC for 512?256
short-wave IR-FPA is presented. This ROIC of a high performancein frame rate can integrate and read out the low signal. Parasitic
capacitors and resistances are taken into account. An analog signal
chain, which contains CTIA, CDS module, amplifier of charge andcomplementary output stage, can satisfy the high frequency and low
signal application. The improved CTIA can get a gain of 75dB withlow power dissipation. The CDS which works well in the previous
design is retained. To improve the output voltage range, the amplifierof charge is employed, with which we can amplify the output voltage
linearly. The structure for power supplying is changed to strengthen
the reliability. The layout has been improved according to the practicaltest. The simulation and verification are completed both before andafter completing the improved layout. The circuit’s structure andoperation principle are analyzed under the environment of mix-signal,and the result shows that the output dynamic range is over 2.5V, thewell capacity is more than 1Me-, the frame rate is 250Hz, the linearity
within useful dynamic range is above 99.9 percent, even when thetemperature is about 77K. This ROIC is a full-custom flow integrated
circuit design. The parasitic parameters are extracted once the layout
is finished. Then the design is improved according to the result of
post-layout simulation, which leads to the great improvements of mostparameters.

Bo Wang, Wenfeng Gong, Chensheng Wang, Huazhong
Institute of Electro-Optics-Wuhan National Lab. for
Optoelectronics (China)
In this paper, an infrared and color image fusion algorithm basedon luminance-contrast transfer technique is presented after carefulresearch on multi-channel and multi-sensor pixel level fusion algorithm.
This algorithm shall operate YCbCr transform on color visible image,and obtain the luminance component. Then, the grey-scale image
fusion methods like grey-scale weighting average method and pixel
comparison method are utilized to fuse the luminance componentof visible and infrared image, so that the grey-scale fusion image isacquired. After that, the grey-scale fusion image and visible image arefused to form color fusion image based on inversed YCbCr transform.
In this step, the grey-scale fusion image is taken as the luminancecomponent, and the visible image is taken as the color component.
This algorithm has the advantages of low computation consumption
and natural color effect, but the details appearance is not ideal. To
acquire better details appearance, a natural-sense color transfer fusion
algorithm based on reference image is proposed by utilizing the meanvalue and variance transfer of grey-scale reference image. In thisway, the luminance and contrast characteristics of reference imagetransfer to grey-scale fusion image, and the color fusion image quality
is improved. Furthermore, a real-time double channel infrared/visible
image fusion system based on FPGA is realized. Finally, this design andachievement is verified experimentally, and the experimental results
show that the system can produce a color fusion image not only with
the natural color appearance similar as the input color visible image, butalso with pleasing luminance and contrast.

8562-67, Poster Session

Theoretical and experimental researchon recovering absorbance shape withwavelength modulation spectroscopy
Zhimin Peng, Yanjun Ding, Tsinghua Univ. (China); lijuan Lan,
Tsinghua University (China)
The measurement accuracy of absorbance shape directly determines
the temperature, pressure, and concentration measurement accuracy
in tunable diode laser absorption spectroscopy (TDLAS). However,
the traditional direct absorption spectroscopy is easily influenced byparticles concentration, laser intensity fluctuations, and baseline-fitting
errors that often hamper the accurate determination of absorbanceshape. As a result, meeting measurement requirements becomes more
and more difficult. In recent years, with the recognition of the powerof wavelength modulation spectroscopy (WMS) for highly sensitive
measurements, many scientists have applied WMS in a number ofareas to measure gas temperature and species concentration, andvaluable findings have been obtained. However, the methods applied tomeasure absorbance shape based on WMS remain to be in the stageof exploration, and an efficient and acceptable method has not yet
been developed to date. In the present paper, harmonic expressions
were derived based on the absorption spectral and harmonic theories,
and we also mathematically proved that the absorbance shape can bedirectly recovered, when the data of the X and Y axes of odd harmonic
are processed by the method established in the current study. In
validating the precision of this method, the transitions of NH3 andCO2 are selected to recover the absorbance shape using numericalsimulation and experimental techniques.

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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies II

8562-68, Poster Session

8562-70, Poster Session

Terahertz polarizing beam splitter based on
copper grating on polyimide substrate

Terahertz multiband filters fabricated bylaser induced and non-electrolytic plating

Mengen Zhang, Xiangjun Li, Wentao Wang, Jianjun Liu, Zhi
Hong, China Jiliang Univ. (China)

Wentao Wang, Jianjun Liu, Xiangjun Li, Hao Han, Zhi Hong,
China Jiliang Univ. (China)

Terahertz polarizing beam splitter with high extinction ratio, large
angular apertures, low attenuation and broadband polarization has
recently attracted great interest owing to potential applications interahertz imaging and spectroscopy. In this article, a terahertz polarizing
beam splitter, based on a copper grating on polyimide (PI) substrate,
was fabricated by the way of laser induced and non-electrolytic plating.
The good polarization characteristics of the splitter in the range of
0°~180° polarization are verified experimentally using backward wave
oscillator at fixed frequency of 300GHz, and the insertion losses of
0.13dB and 0.32dB are measured for the transmitted and reflectedbeams, respectively. And the transmitted and reflected powers,
normalized to the measured power in the absence of the beam
splitter, followed the expected square of cosine relation as a functionof polarization angle. The broadband transmission of TM wave of the
splitter were also measured by terahertz time-domain spectroscopy,
and the extinction ratio larger than 22dB is obtained in the frequency
range of 0.2~1.5THz, experiment results were limited by the noise levelof the time-domain spectroscopy setup. The theoretical simulation,
based on finite element method, was used to discuss the variation ofreflection/transmission characteristic and extinction ratio with different
grating period or filling factor. According to the simulation results, thesmaller grating period or the bigger filling factor would generate thehigher extinction ratio but the lower transmittance. The theoreticalsimulations show a good agreement with experiment results.

Terahertz resonant devices based on metal-dielectric microstructures
can be used for various applications such as spectral imaging, opticalmodulators, wave-tunable filters and biosensors. In this paper, we
report the design, fabrication and characterization of two multiband
terahertz bandstop filters. One of the filters is composed of threedifferent square rings, and the other is the combination of individualU- and T-shape. Finite-difference time-domain modeling was used
to design the structure of the filters at first. And they were fabricatedon polyimide substrates by laser induced and non-electrolytic platingwith copper due to its simplicity and flexibility to manufacture metaldielectric microstructures compared to conventional photolithography.
The performance of the fabricated filters was measured using aterahertz time-domain spectroscopy. Three different central frequencies
are demonstrated at 0.33THz, 0.68THz and 1.13THz for the squarerings filter. And the TU-shaped one shows three distinct resonances at
0.37THz, 0.73THz and 0.96THz. The experimental results are in good
agreement with finite-difference time-domain simulations. In order tounderstand the multispectral response, we analyze the magnetic filed
distributions of the corresponding resonance frequencies. For thesquare rings, the three resonance peaks are originated independently
from the external, middle and inner square ring, respectively.
Accordingly, the first and third order modes of the UT-shaped filter are
originated from the individual U- and T-shape, while the second mode isfrom the interaction between them.

8562-69, Poster Session

8562-72, Poster Session

The design of infrared spaceborne remotesensing signal processing circuit for multispectral and multi-focal plane

Methane gas detection using an intergrating
sphere as a multipass absorption cell in midinfrared band

Tao Liu, Beijing Institute of Space Mechanics and Electricity(China)Huan Xue Wang, Yihuai Lu, Tian Shu Zhang, Anhui Institute of
Optics and Fine Mechanics (China)

With the rapid development of space cameras and remote-sensing
application technology, photoelectric sensor of the remote sensing
satellite have evolved from the single-spectral, single type, single focal
plane to the multi-spectral, multi-type, multi-focal plane integration
direction. At present, the manufacturing process of the infrared
detector has a larger improvement, but compared to the CCD device,
the resolution is still low. In order to improve the resolution of infrared
imaging systems, infrared imaging system using jointing multi-focal
plane array can increase the resolution of infrared imaging systems. At
present, remote sensing satellite equipped with a visible light detector
and infrared detector, and design of multi-spectral, multi-type, multifocal plane imaging circuit has become a new challenge. For multispectral, multi-, multi-focal plane imaging characteristics of the circuit
system, this paper analysis and design of the FPGA signal processing
circuit for multi-spectral, multi-focal plane jointing infrared imaging
system, which includes time base correction circuit, infrared detector
timing control circuit, multi-channel analog signal delay correction
circuit, multi-channel uncertainty calibration circuit, average filtering ofover-sampling circuit, multi-channel image data reading and correction
circuit. Details the various parts of the design ideas and methods,
design, simulation and testing. The test results show that the design iscorrect and feasible to meet the design requirements.

The reduction of harmful environmental pollutants can have adeverse
effects on human health, so more and more researchers concentrate
their attention on the detection of this pollutants of low concentration.
This paper describes a new method of detecting methane
concentration. The integrating sphere has an internal coating which ishighly reflective in mid-infrared band (over 95%) and was used to input
and output methane gas and other interfering gas(For example,water
vapor, carbon dioxide and so on ). We used a LED (centre wavelengthof 3.31)as a light source and a photodiode as the detector. In orderto gain a better reference spectra and improve the accuracy of themeasurement, we applied the air filter technology in this experiment.
When the concentration of methane gas changed, the optical path
length changed with it, which has a linear relationship. Thus, it improved
the simplicity and convenience of our experiment largely. The resultof the experiment agreed with the basic theoretical model. According
to the results of our experiment, signal pulse of 2 mA enable to detect
0.3%v/v of methane at 1cm path. The limit of detection at integration of
1mA singal over 1s is around 18 ppm. The result showed this method
is a promising technique for determining the low concentration of
methane gas.

8562-73, Poster Session

THz microcavity design using modal method
Xiaoyuan Lu, Xi’an Institute of Optics and Precision Mechanics(China)No Abstract Available
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Infrared, Millimeter-Wave, and Terahertz Technologies II

8562-74, Poster Session

High-frequency analysis on RCS fromterahertz conductive targets in free space
Houqiang Hua, Beijing Univ. of Aeronautics and Astronautics(China)Numerous authors have derived a variety of methods that are used forcomputing the high-frequency radar cross section (RCS) of complex
radar targets in the microwave or lower frequency bands in freespace. A variety of RCS prediction software has been widely used
for interactive modeling, design, and analysis of aircraft with RCS
specifications in the microwave or lower frequency bands, such as
XPATCH, CADDSCAT, RESPECT, GRECO, and RANURBS, which are
based on the high-frequency techniques and provide an efficient tool
to obtain real-time results. But in the scope of the authors’ knowledge,
it has not been reported that the electrically extremely large conductive
targets in free space were calculated by the high-frequency methods in
the Terahertz band.
With the development of the electromagnetic and Terahertz technology,
the researchers have directed significant attention toward the targets
in free space, especially the electrically extremely large perfectly
electric conducting (PEC) targets outside the atmosphere or in spacein many fields, such as military, astronomy, remote sensing and wave
propagation. The scattering fields of the targets in free space could becomputed by using the finite-element method (FEM) or finite-differencetime-domain methods (FDTD), but they cause some difficulties inthe solution procedure. Some researchers try to combine the freespace Green’s function and the method of moments to consider theelectrically extremely large targets in free space, but it also requires
more mass storage memory, which results in lower processing speed
and computational efficiency.
This paper focuses on the prediction of RCS of conductive targets withelectrically extremely large size in the Terahertz band in free space. In
order to consider the scattering fields of the electrically extremely large
PEC targets in free space, the Green’s function was introduced into theconventional physical optics method. Combined with the graphicalelectromagnetic computing (GRECO) method, the shadow regions are
eliminated quickly by displaying lists technology of OpenGL to rebuild
the target, and the geometry information is attained by reading the colorand depths of each pixel. The RCS of Terahertz conductive targets canbe exactly calculated in free space. The numerical results show that thismethod is efficient and accurate.

8562-75, Poster Session

Low frequency collective vibrational spectraof zwitterionic glycine studied by density
functional theory
Shihua Ma, Institute for THz research, Southeast University(China); Hua Chen, Southeast University (China); YiPing Cui,
Institute for THz research, Southeast University (China)
As the simplest protein structural unit and the smallest amino acid,glycine plays an important role in building proteins, constructing of
RNA as well as DNAs, and aiding the absorption of calcium in thehuman body. Considerable efforts have been dedicated to suchstudies on glycine under various experimental conditions and using
different theoretical methods. However, most of the works so far wereconfined in the mid-infrared spectral region and the research on the
low frequency vibration modes is too limited to parallel with the great
demand for the rich information that the spectra could provide in thisspectral range.Therefore, there are many problems still are open. For
example, due to the collective vibrational modes in low frequency
spectral range are influenced greatly by the change of structuralelements, conformation states and the surrounding environment, someassignments need further confirmation, and some absorption bands
were left unassigned, the numbers of the vibrational modes and theother spectral features in theoretical calculation are quite different
from the experimental observations from time to time. Therefore, more
attentions and efforts are needed in the FIR spectral range.
In this paper, DFT was employed to calculate the geometric structure
and vibrational frequencies of the zwitterionic glycine in FIR region.
Detailed assignments of the observed vibraional frequencies are given
and the origins of some frequencies are analyzed. The low frequency
collective mode of zwitterionic glycine is affected greatly by theintermolecular interaction besides hydrogen bond. At the same time,
the low frequency collective vibrations of two more zwitterionic glycines
are calculated, and there is more reasonable qualitative agreement
between the calculated data of crystalline and observed line positions.

8562-76, Poster Session

Removal of complex-conjugate ambiguity in
SDOCT by using phase shiftings
Wenyuan Cai, Zhuqing Jiang, Yujia Wang, Hao-Chong Huang,
Yu-Hong Wan, Beijing Univ. of Technology (China)• Spectral-domain optical coherence tomography (SD-OCT), as a
new imaging technique developed rapidly in recent years, has widely
prospective applications in clinical medicine, biomedicine and materialscience due to its high-resolution, high sensitiveness, non-invasion
imaging. However, only one half of the imaging depth range is actuallyeffective in the use of SD-OCT due to complex-conjugate ambiguity
inherent to Fourier transform of real number data. Consequently,
removal of complex-conjugate ambiguity is required to make the full
depth range possible and to provide a flexible positioning for a zeroplane. In order to resolve the complex-conjugate ambiguity, traditional
phase-shifting technique is exploited in the work of image processing.
The three-steps or more steps phase shifting method is used by mostresearch, with which two or more phase shift operation is needed in
the experiment. However, the image quality with more than three steps
phase shifting may be reduced due to more than once operation, andimaging speed is also limited. In this paper, two steps phase-shifting,which only single phase shifting operation is needed, is utilized in digital
image processing to resolve the complex-conjugate ambiguity andeliminate the influence of more steps phase-shifting operation on thequality of reconstructed image in FD-OCT. Based on the advantage ofsingle-phase shift operation, quick phase shifting with waveplates orother optical elements is possible, without using a translation stage.
The cost of the system may be lowered which makes it more practical.
The feasibility and validity of this method is demonstrated by thereconstructed image.

8562-77, Poster Session

Infrared image quality assessment based on
fractal dimension method
Zhijie Zhang, Jufeng Zhang, Song Yue, Chensheng Wang,
Huazhong Institute of Electro-Optics-Wuhan National Lab. for
Optoelectronics (China)
The using and observation experience of users is affected by the qualityof infrared images which are collected by infrared imager. The image
quality which would decline during the operation procedure as timegoes on, and the severe climate is also a significant influence factor forthe performance of image processing algorithm and the optimizationof system parameters as well. An image quality reduced reference
evaluation model is put forward to evaluate the degree of infrared
image quality reduction. The image texture roughness is describedby fractal dimension which is the denotation of image stability. The
detail characteristic of infrared image texture is extracted by the fractal
dimension analysis method proposed in this paper as the representationof image quality. The method calculates the fractal dimension of eachpixel one by one with a multi-scale window over the entire image to
get the corresponding information of adjacent image block. A quality

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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies II
information image is mapped from the fractal dimension of all pixels
to describe the infrared image quality. The parameters of the quality
information image combined with the signal noise ratio of original
infrared image are adopted as the metric of infrared image quality.
The verification experiment of this evaluation shows that the infrared
image can be graded by this method very well. As the compromise offull reference evaluation image quality method and no reference image
quality evaluation method, this method can be embedded into theimage processing system to optimize image processing algorithms andparameters settings, and can also provide reference for fault diagnosis.

8562-79, Poster Session

Optimization for the heating pulse used
in infrared thermography non-destructive
testing technology
Guo Li, Lichun Feng, Cun-lin Zhang, Capital Normal Univ.
(China)Pulsed-heating infrared thermography non-destructive testing is one of
the most common used technology in industial NDT/NDE. Comparedto other theories used in infrared thermography non-destructive testingsuch as lock-in method, pulse-heating method has an advantage on
simple instrument and easy operation while maintains a considerable
accuracy. The ways used to produce a heating pulse contain flash
lamp, laser, electromagnetic coil, high-temperature object contact,etc. These different ways mainly vary on heating energy and shape ofheating pulse. To get an persuasive result, heating energy and width ofheating pulse should be adjusted to real testing condition, which mainly
depends on depth of defect and thermal conductivity of material. This
paper tries to derive a method for a proper chosen of properties ofheating pulse. The method is based on theory of thermal wave. First,
heating pulse can be decomposed into a series of thermal waves withdifferent spatial frequencies by Fourier transform, each thermal wave
will be analyzed to evaluate its effect on creating surface temperature
difference, which leads to infrared radiation difference. Then the widthof heating pulse will be chosen to make itself contain more effective
frequency components. During this process, the shape of different
heating pulse should be taken into consideration. Heating energy will
also be calculated to get a considerable contrast of infrared radiation.
Finally, the effect of this method can be verified by simulation and NDTexperiments in this paper. The method in this paper can provide areference for practical NDT or NDE technology.

8562-81, Poster Session

An improved algorithm based on ROMP usedin THz imaging
Ze Li, Xiaohua Liu, Yuejin Zhao, Beijing Institute of Technology(China); Cunlin Zhang, Capital Normal Univ. (China)
In lots of reconstruction algorithms of Compressive Sensing(CS),the reconstructed result of Regularized Orthogonal Matching Pursuit(ROMP) algorithm is better than others, but , the better reconstructedresult of the algorithm is based on the fact that the number of iterations
is equal to the sparsity of the original image, and the reconstructedresult of the image is connected with the number of iterations to a great
extent, thus, it’s very important to estimate the sparsity of the original
image accurately, if the estimated sparsity is lager or smaller than fact,
the result of ROMP algorithm will be influenced seriously. To solve thisproblem, an improved algorithm that based on ROMP was proposedin this paper, in order to determine the best number of iterations
automatically and achieve a better reconstructed image, the algorithm
determines whether the number of iterations is the best or not by theprevious result , instead of estimating the sparsity of the original image.
Finally, a series of experiments was done, and the experimental resultshow that the result of this improved algorithm is better than the resultof the previous ROMP algorithm with deterministic iterative number.

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8562-82, Poster Session

A signal processing system of infrared
remote sensing camera based onoversample and comb filter
Ning Lei, Hua Wang, Zhiyong Wei, Tao Li, Beijing Institute ofSpace Mechanics and Electricity (China)
Infrared remote sensing camera is a two-dimensional imaging device.
The energy distribution of infrared radiation is detected and display
using the temperature radiation and emittance differences between
the target and the environment. There is variety of noises in the output
of infrared detector, such as quantization noise, heat noise, 1/f noise,
fix-pattern noise, non-uniformity noise, and so on. The presence of
these noises is affected the performance of the infrared image andother processing algorithms. In this paper, a new signal processing
system of infrared remote sensing camera is given. This system is used
to condition and enlarge the output analog signal of infrared focal planearray. And then, the converted digital signal is processed in FPGA.
Finally, the image data is output to data transmission system. The signal
processing system is consisted of FPGA, ADC chip, SRAM memory,and so on. Digital low-pass filtering, pixel response non-uniformity
correction, data synthesis and the conversion of output data format
are implemented in a single FPGA. The SNR is improved by denoisingalgorithm based on oversample and comb filter, and the non-uniformityof infrared detector is eliminated by real-time correction method basedon two-point correction algorithm. This system is easy to implement
and can be applied in imaging device widely. The experimental results
show the performance of imaging system is improved.

8562-83, Poster Session

High-range resolution profile of terahertz
radar
Meiyan Liang, Capital Normal Univ. (China)
Step frequency signal is one of the more commonly used radar signal
for high range resolution, it commonly used in radar target recognition.
The wavelength of Terahertz signal is shorter than that of microwave, so
it is easy to realize the high range resolution. The paper first introduces
the step frequency signal to obtain the one-dimensional distanceimage, and analyzes the principle of high range resolution profiles ofstep frequency radar. Then, the 0.2THz step frequency radar systems
are introduced. Finally, the high resolution range profiles are achievedby the simulation of Matlab. The simulation results show that the step
frequency THz radar can reach centimeter level high resolution.

8562-85, Poster Session

A novel 32x1 readout integrated circuit withhigh dynamic range for IRFPA
Zhuang Miao, Ning Li, Zhifeng Li, Shanghai Institute ofTechnical Physics (China)
With the fast development of the infrared focal plane arrays (IRFPA)
in recent years, the infrared imaging technology has been widely
applied in various fields. As an important part of the IRFPA, thereadout integrated circuit (ROIC) with wide dynamic range and highsensitivity has become one of the main research areas for the highperformance IRFPA. In this paper, a novel 32?1 ROIC with high dynamic
range is presented. The ROIC contains a capacitive trans-impedance
input amplifier (CTIA integrator), followed by a comparator that set a
threshold voltage for comparing the integrating signal. It contains thetime-to-threshold information in adding additional dynamic range
with a linear voltage ramp input, in addition to the regular integration
signal. By the end of integration, if the integration signal is less than
the threshold voltage, the integration signal is sampled for readout.

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When the integrating signal is reached to the threshold voltage
before the end of integration, the ramping voltage is stored and later
sampled for readout in representing the signal level and a digital flagis set in recording the event of trigger. Thus, a high level signal can besaved before it saturating the integrator. A test chip of 32?1 ROIC is
designed and fabricated with 0.35 µm triple metal, double poly CMOS
technology. The chip test results prove correct function of the circuitwith 3.3 V power supply. The results of tracing one channel show thatthe dynamic range increase 58 dB with a 10-bit ADC and the readout
clock frequency is up to 10 MHz.

8562-86, Poster Session

A new ROIC with high-voltage protection
circuit of HgCdTe e-APD FPA for passive andactive imaging
Guoqiang Chen, Shanghai Institute of Technical Physics (China)
HgCdTe electron avalanche photodiode in linear multiplication modecan be used for high speed applications such as active imaging. A
readout integrated circuit of e-APD FPA is designed for active/passive
imaging system. Cell circuit architecture of ROIC includes a high voltage
protection module, a Sample-Hold circuit module and a integrator
module which includes a preamplifier and two capacitors. Generally,
APD FPA works at high reversed bias such as 10V-15V in active mode,and pixels’ dark currents increase exponentially as the reverse-bias
voltage is increased. Some cells of ROIC may be short to high voltage
because of blind pixels or breakdown of pixels. If there is no protection
circuit, these cells will be burnt out, and then the whole ROIC is burnt
out. Thus a protection circuit module introduced in every ROIC cell
circuit is necessary. Conventional 5V CMOS process is applied to
implement the high voltage protection with the small area other thanLDMOS in high voltage BCD process in the limited 60um?60um pitch
area. In integrator module, two capacitors are included with a CTIA
input stage to integrate e-APDs’ photocurrent, one of them can beshared in two modes in order to save area. The integration time inactive mode can be altered by the step of 10ns. A cascode structure is
performed as pre-amplifier to reduce the power consumption, area andto void potential instability caused by inaccuracy of MOSFET Model at
77K.

8562-24, Session 6

Double channel mechanically tunableterahertz filter based on parallel platewaveguide cavities (Invited Paper)
Lin Chen, YiMing Zhu, Univ. of Shanghai for Science andTechnology (China)
Theoretical and experimental works were carried out on a double
channel mechanically tunable terahertz filter integrated with parallel
plate waveguide cavities. The filter includes two rectangular grooves
on upper and bottom plates of waveguide, respectively. The filteredfrequency can be linearly tuned by altering the overlap distance
between the two rectangle grooves on metal plates together with the Q
values. From the experiment, we found the central wavelength can be
adjusted from 0.403THz to 0.412THz at low frequency and 0.348THz
to 0.366THz at high frequency, and the Q values can reach 46 when
the resonant frequency is 0.41THz. Theoretical results show good
agreement with experiment.

8562-25, Session 6

Millimeter-wave imaging with frequency
scanning antenna and optical arrayedwaveguide grating (Invited Paper)
Yuntao He, Guoxin Yu, XinYu FU, Yuesong Jiang, Beihang Univ.
(China)A novel millimeter-wave (MMW) imaging method using frequency
scanning antenna and optical arrayed waveguide grating is proposedin this paper. The wideband MMW signal processing has been a big
problem in the MMW imaging system with frequency scanning antenna.
In the proposed method here, the wideband signal collected by MMW
frequency scanning antenna is modulated to the optical domain by aphase electro-optical modulator (EOM). The carrier is suppressed andthe first side band (FSB) of the modulated optical is transmitted to a
special designed optical arrayed waveguide grating (AWG). The AWG
could is used to read out each ultra narrow band of the FSR which
represents the received wideband MMW signal synchronously. As
every narrowband of the received MMW corresponds to every different
induced angle, so the real time imaging can be achieved by a simple
processing of the output of the AWG.
The principle of the advanced imaging method is analyzed theoreticallyfirstly. A 34~ 44GHz frequency scanned antenna is then designed
carefully with a field of view of 40 degrees for the MMW imaging
system. The received wideband MMW signal is amplified with awideband preamplifier from Cernex Corp. and modulated by a Convege
40GHz phase EOM. An AWG of 1x32 is designed specifically with achannel spacing of 0.3GHz. A simulated imaging system is constructedby the designed results and those components in lab. The designingand simulating demonstrated the feasibility to set up such an imaging
system which is progressed.

8562-27, Session 6

A new design of signal processing system
for TDI infrared focal plane array
Hua Wang, Tao Li, Xu Wang, Ning Lei, Zhiyong Wei, Beijing
Institute of Space Mechanics and Electricity (China)
In this paper, according to the output signal characteristics of TDI(TimeDelay Integration) infrared focal plane array, a novel signal processing
system based on AC coupling technology is proposed. Firstly, theoutput signal characteristics of TDI infrared focal plane array are
analyzed. The key feature is that the output sequence of signal in eachline cycle of TDI detecto is several reset signals followed by a certain
number of valid signals, and the level of reset signals is fixed in a given
TDI detector. Secondly, the signal processing system based on AC
coupling technology is introduced. The designed system is consistof high pass filter circuit, signal condition circuit, differential input
analog to digital converting circuit and digital data processing circuit.
DC component of output signal from TDI infrared detector is removedby high pass filter circuit. The remaining AC signal is conditioned bysignal condition circuit and is converted to digital data by differential
input analog to digital converting circuit. The digital DC restoration ofvalid signals from detector is implemented by digital data processing
circuit, which references the digital data of the reset signals. Finaly,
the designed system is simulated and tested. Simulation and test
results show that the novel design idea of signal processing circuit isreasonable and feasible. Compared with the traditional design, thesystem has the characteristics of high common mode noise rejection,
low level drift and low power consumption.

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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies II

8562-28, Session 6

Aluminum-coated hollow waveguides for thetransmission of terahertz radiation
Jing Liu, Jingling Shen, Captial Normal Univ. (China)
We have applied techniques developed for IR waveguides to fabricate
Al-coated hollow PTFE waveguide(HPW)s for transmission of terahertz
radiation. A wavelength tunable Backward Wave Oscillator(BWO) is
used as the THz source. The losses for these hollow-core waveguideare measured by a Pyroelectric detector. Losses at frequencies range
from 200GHz to 210 GHz are obtained for 8mm bore, 15/20/30cm long
Al HPWs. We also test the hollow PMMA waveguide in such range of
frequencies. Further simulation is done besides experiments.

Shi, Purple Mountain Observatory (China); Hiroyuki Maezawa,
Osaka Prefectural University (Japan); Scott Paine, HarvardSmithsonian Center for Astrophysics (United States)
In this paper, we will introduced a dual-THz-band SIS (SuperconductorInsulator-Superconductor) heterodyne radiometer system developed
for the atmospheric profiling synthetic observation system project(APSOS). This THz system is intended to have a durable and compact
design to meet the challenging requirements of remote operation. The
system as well as its major components such as antenna tipping, quasioptics, cryogenics, SIS mixers and FFTS backend will be discussed
thoroughly. Some scientific simulation focusing on the atmosphericprofiling componets at THz bands will also be investigated.

8562-31, Session 78562-29, Session 7

Terahertz super thin planar lens (Invited
Paper)Yan Zhang, Capital Normal Univ. (China)
TERAHERTZ (THz) radiation has attracted extensive attentions in
the past decades. Many developments have been made in the fields
of sources, detector, and applications. However, due to the longwavelength property of the THz radiation, the size of the opticalelements for dominating THz beam is quite large. They are not suitablefor THz system integration. Based on the diffractive optics theory,
the thickness of an element, for example, a lens can be reduced fromseveral millimeters for bulk elements to several hundred micrometers for
diffractive optical elements. However, this size is still too large for some
applications. Is it possible to reduce the thickness of the THz lens?
A recently published paper presents a possible approach to reduce thethickness of the THz lens further1. For a V shaped metal antenna, theilluminating radiation will resonate with the chargers generated on thesurface of metal. By accurately selecting the lengths of two arms andthe angle between two arms of the antenna, the amplitude and phaseof the resonance wave can be effectively controlled. If the antennas are
selected with same resonance amplitude but different phase sampledfrom 0 to 2p with equal step, one can use these antennas to fromarbitrary elements based on the theory of diffractive optics. The size ofthe antennas is about 1/4 of the wavelength and the thickness of theantennas is only 1/4000 of the wavelength.
The amplitudes and phases of transmitted waveforms of the antennas
with different arm lengths and angles have been theoretically calculatedusing the finite difference time domain method, 8 antennas with sametransmitted light amplitude are selected. The phase difference between
two adjacent antennas is p/4. Using the diffractive optics theory, a lenswith 4mm focus length for 0.75THz is design and the phase distribution
is quantized. The corresponding antennas are selected to generate
difference phase difference. The samples are fabricated on a100nm
thick gold film on a silicon wafer substrate with the traditional opticallithography method.
The sample is characterized with a THz focusing plane imaging system.
The range of the THz radiation is 0.2-2.6THz. The sample is located
4mm away from the detection crystal and under the plane wave
illuminating. The waveform at each point on the detection crystal canbe achieved via scanning the time delay. After the Fourier transform,
the complex amplitude distribution on the focusing plane for 0.75THz
can be obtained. The THz wave has been well focused to a point. The
FWHM of the focus point is about 400µm. The thickness of the lens isonly 1/4000 of the illuminating wavelength.

8562-30, Session 7

Atmospheric profiling synthetic observation
system at THz (Invited Paper)
Qijun Yao, Dong Liu, Jing Li, Zhenhui Lin, Zheng Lou, Shengcai
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640x512 InGaAs focal plane array camera for
detecting 1.58um absorption spectra of CO2
Wei Peng, Lei Ding, Xianghua Wang, Shanghai Institute ofTechnical Physics (China)
This Paper introduces a 640x512 InGaAs focal plane array (FPA) camera
for measuring 1.58µm absorption spectra of CO2. To gain atmospheric
CO2 concentration by detecting short wave infrared of reflective
sunlight has been demonstrated to be an effective way. A hyperspectral
spectrometer is designed to detect 1.58µm absorption spectra of CO2.
The spectrometer is a grating spectrometer which is able to responseto the spectral range from 1.561 ~ 1.591µm with spectral resolutionof 0.1nm. For high sensitivity, F number is determined to be 1.8. We
designed a 640x512 InGaAs FPA camera coordinating with the grating
spectrometer.
The camera integrated a 640?512 InGaAs FPA with a 25 µm pixel pitch.
The 640x512 InGaAs FPA has characteristics of quantum efficiency noless than 65% at wavelength of 1.58 µm, pixel operability more than
99.91%, two gain modes and three integrate modes. The 640x512
InGaAs FPA is sensitive to 0.9µm-to-1.7µm short wave infrared (SWIR)
band and features a 298 K temperature detectivity, D*, greater than
5?1012 cm-&#8730;Hz/W. The camera features 3Hz rate (exposuretime) and 14-bit output. The FPA’s TEC module is controlled to keep
the detector core at low temperature. The detector core temperatureis going to be adjusted to below 253 K for lower readout noise anddark current. A Universal Series Buses 2.0 (USB2.0) has been used totransmit images and commands. Commands of window size, position,
Gain mode and integrate time per frame can be sent by the USB2.0
interface.

8562-32, Session 7

A kind of wide range imaging spectrometerbased on deformed Michelsoninterferometer
Liu Yang, Beijing Institute of Technology (China)
Ultraviolet(UV), Visible and Shot-wavelength infrared(SWIR) band
Imaging spectrum technology is widely used in various filed such as
astronomy, remote sensing, biology, chemistry, etc. This paper will
describe a new kind of imaging spectrometer which working band
could cover UV to SWIR(250nm-1700nm) just by switching detector
and band-pass fillter. It is a kind of time modulated Fourier Transform
Imaging Spectrometer base on deformed Michelon Interferometer
witch no moving mirror and one of the mirror rotated a tiny angle fromit symmetry position. It could achieve much higher light flux then spacemodulated type and also without moving part in the interferometer
witch highly sensitive to external environment. A catoptric imaging
lens which called offner system were also be used to ensure there is
no chromatic aberration and high resolution during the whole working
band. The object lens and beam splitter were made by Fused Silica andthe catoptric imaging lens to ensure the whole optical system had high190A  
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Infrared, Millimeter-Wave, and Terahertz Technologies IItransmission from 250nm to 1700nm?.
The model of this interferometer will be established in this paper, thewindow scan and date processing will also be discribed. Several
experiments had been made in different spectral band and the results
will be given at the end of this paper. It shows that the imaging
spectrometer could obtain and reconstructed spectral data cube
correctly in each spectral band, and the resolution of wavenumber isbetter then 160cm-1 in UV–visible band, better then 60cm-1 in SWIR
band.

8562-33, Session 8

THz radiation properties of siver coneantenna arrays (Invited Paper)
Mingzhe Hu, Guizhou Univ. (China); Kaijun Mu, Cunlin Zhang,
Capital Normal Univ. (China); Ding Zhao, Guizhou Univ. (China)
THz wave finds wide and important applications in drug, bombing
and metal danger material detecting, biochemical imaging and foodsafety detecting. Recently, J.F.Scott et al. reported for the first timethat a wide bandwidth THz radiation could be generated by irradiating
PZT ferroelectric nanotube array with femto second pulse laser, which
can radiate a 2?8THz THz pulse, expanding the THz band gap thattraditional semiconductor cannot cover. Moreover, the micrometer ornanometer scale sized antennas possess large surface area and highsurface carrier mobility, which will enable a significant improvementof radiated THz power. Therefore, the novel THz radiating technology
based on micrometer or nanometer antenna arrays has a potential
capability to overcome the present bottleneck of narrow THz bandwidthand low radiation power in traditional electrooptic crystals andphotoelectric conductors. In the present work, we set the silver coneantenna and its array antenna as the investigation objects. The THz
properties, including the electromagnetic field distribution, of theseantennas radiated by the femto second laser were investigated using
the moment method and the CST microwave studio software. We
designed a single Ag cone antenna and moment method is employed toanalyze the solution process of the integrate equation of the irradiatedelectric field. Results indicate that when the bottom radius of the Ag
antenna cone is 5µm and the height of the cone is 22µm, the bandwidthis 7.9~6.8THz at the working frequency of 7.3THz. The radiation gain of
the THz electromagnetic wave of the single Ag cone antenna is 22.7dBi
under the resistance matching condition. Moreover, the radiation
pattern can be effectively improved through combining the single Ag
cone antenna into N?N square arrays and the radiation gain can also beenhanced to 42.5dBi.

8562-34, Session 8

Near-field thermal radiation characteristics
of metamaterials
Yang Bai, Yongyuan Jiang, Harbin Institute of Technology(China)In this paper, we theoretically derived the local density ofelectromagnetic state (LDOS) in vacuum above a semi-inﬁnite
metamaterial. Simulated result of permittivity and permeability wereused to analyze the LDOS and heat transfer of metamaterial. It showedthat p-polarization surface wave is the main contribution to near fieldenhanced radiation for electrical response; s-polarization surface
wave is the main contribution to near field enhanced radiation formagnetic response. The method used and results obtained from thisstudy suggested a convenient way to control the enhanced near fieldradiation.

8562-35, Session 8

Fast angle catching methods of a millimeterwave radar for hypersonic aircraft
Haibin Zeng, Ying Huang, BITTT (China); Tao Li, EAAF (China);
Shasha You, BITTT (China)
Because of its high frequency, a millimeter wave radar will meet angle
catching problem for hypersonic aircraft. One hand, antenna beamwidth of a millimeter wave radar is remarkably narrow comparing withordinary centimeter wave radar as the same antenna size. On theother hand, Doppler dynamic will be much bigger than that of a lower
frequency radar. These two factor make a millimeter wave radar needa fast angle catching method to avoid target fly away antenna beam or
too bigger Doppler make signal can not be locked.
In this paper, three kinds of methods are introduced: the first one is thedelay-correlation method; the second one is correlation method; thelast one is cycle spectrum correlation method. All these three methods
need no data demodulation, so they can output angle value quickly.
They have different advantages and disadvantages, and are used indifferent condition.
Delay-correlation method is fit for mono-channel and mono-pulse angle
tracking system. The received signal pass a delayer, then correlate withitself. A notable advantage of the method is that it has a very simple
structure. But its performance is not very good when SNR is very low.
Correlation method is fit for double-channel and mono-pulse angle
tracking system .But it can improve the output, reduce the influence ofnoise. Cycle spectrum correlation method has perfect performance. But
it needs much more resource.
This paper introduces theory and performance of these three methods,
especially in high dynamic and low SNR condition .Then it points
out how to select a method in different condition according to theircharacter.

8562-36, Session 8

A novel quasi-optical subharmonically
pumped GaAs diode mixer at 375 GHz
Jie Hu, Zheng Lou, Sheng-Cai Shi, Purple Mountain
Observatory (China)
This paper presents the design, characterization, and the fabricationof a novel quasi-optical subharmonically pumped GaAs Schottky
diode mixer at 375 GHz. It features the use of two off-axis double-slot
antennas to receive the RF and LO signals respectively, aiming to obtaina better coupling efficiency. The mixer circuit together with the antennas
is integrated on a silicon extended elliptical lens. The mixer circuit isbased on coplanar waveguide design and consists of an anti-paralleled
Schottky diode pair, harmonic filters and matching networks. In order toachieve good isolations between RF and LO ports, quarter-wavelength
resonator directly-coupled bandpass filters are introduced at both RF
and LO ports. The IF filter is a seventh order chebyshev lowpass filter
with cutoff frequency at 90 GHz, which will be sufficient to block both
the RF and LO signals. Conventional harmonic balance simulations
in combination with 3D fullwave simulations in HFSS are carried out
to analyze the performance of the mixer. Optimal conversion loss isobtained after impedances of the LO and RF ports are matched. A
5 mW local oscillator power is shown to be sufficient to pump themixer. Finally, measurements at 375 GHz were conducted to verify theperformance of the mixer.

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Conference 8562:
Infrared, Millimeter-Wave, and Terahertz Technologies II

8562-80, Session 8

A low-power SAR ADC for IRFPA ROIC
Lei Gao, Ruijun Ding, Jie Zhou, Pan Wang, Guoqiang Chen,
Lichao Hao, Shanghai Institute of Technical Physics (China)
This paper presents a low power ADC for the 512*512 infrared focal
plane arrays (IRFPA) readout integrated circuit(ROIC). Our work shows
the major structure, the working mode and the simulation result of
the readout integrated circuit. The power supply voltage of 0.35µm
standard CMOS process is 3.3V in this study, and then the dynamic
range of the DI (direct injection) input circuit is reached 2V. Successiveapproximation-register (SAR) ADC architecture is used in this readout
integrated circuit. And each ADC is shared by one column of the
IRFPA. This successive approximation ADC is made up of a 13-bit
digital-analog converter (DAC), a high resolution comparator and adigital control circuit. The most important part is the voltage-scaling
and charge-scaling charge redistribution DAC. In this DAC, charge
scaling with a capacitor ladder to determine the least significant bits
is combined with voltage scaling with a resister ladder to determine
the most significant bits. The comparator uses three-stage operational
amplifier structure to have a 77dB differential gain. The Common-Mode
input rang of the comparator is 1V to 3V, and minimum resolvable
voltage difference is 0.3mV. This SAR ADC has some advantages,
especially low power and high speed. The simulation result shows thatthe resolution of the ADC is 12 bit and the conversion time of the ADC
is 6.5µs, while the power of each ADC is as low as 300µW. Finally, thisSAR ADC can satisfy the request of 512*512 IRFPAs ROIC with a 100Hz
frame rate.

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Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8563 Optical Metrology and Inspection for Industrial Applications II

8563-1, Session 1

A composite quality-guided phaseunwrapping algorithm for fast 3D profile
measurement (Invited Paper)
Ke Chen, Jiangtao Xi, Yanguang Yu, Univ. of Wollongong(Australia); Limei Song, Tianjin Polytechnic Univ. (China)
Fringe pattern profilometry (FPP) is one of the most promising 3D profile
measurement techniques has been widely applied in many areas. A
challenge problem associated with FPP is the unwrapping of wrapped
phase maps resulted from complex object surface shapes. Although
existing quality-guided phase unwrapping algorithms are able to solve
such a problem, they are usually extensively computational expensive
and not able to be applied to fast 3D measurement scenarios. This
paper proposes a new quality-guided phase unwrapping algorithmwith higher computational efficiency than the conventional ones. In
the proposed method, a threshold of quality value is used to classify
pixels on the phase maps into two types: high quality (HQ) pixels
corresponding to smooth phase changes and low quality (LQ) ones
to rough phase variance. In order to improve the computational
efficiency, the HQ pixels are unwrapped by a computationally efficient
fast phase unwrapping algorithm, and the LQ pixels are unwrapped bycomputational expensive flood-fill algorithm. Experiments show that the
proposed approach is able to recover complex phase maps with thesimilar accuracy performance as the conventional quality-guided phaseunwrapping algorithm but is much faster than the later.

8563-2, Session 1

An approach to compensate the object
movement errors in phase shift profilometry
Lei Lu, Jiangtao Xi, Haiping Du, Yanguang Yu, Univ. of
Wollongong (Australia); Limei Song, Tianjin Polytechnic Univ.
(China)Phase shift profilometry (PSP) technique is widely used in 3-D shapemeasurement for many applications. However PSP needs multiple
fringe patterns projected onto the object and reference plane tocalculate the phase value, the object must be static when themeasurement is taken. If the object moves during the measurement,
significantly errors can be introduced to the phase result. Zhang and
Yau used a modified two-plus-one phase shift algorithm to alleviate
the errors due to motion. Because the phase value only contains in
the first two fringe patterns, the measurement error due to motion isless. Wang and Zhang et al. solved for the phase unwrapping errors
caused by rapidly moving object. However they still cannot reducethe inherent phase error caused by motion. This paper analyses therelationship between object movement and phase value, and proposes
a compensation method for errors caused by two dimensional
movement of object. Through the compensation algorithm, the errors
caused by two dimensional movement of object can be eliminated. The
effectiveness of the proposed technique is tested and verified by both
simulations and experiments.

8563-3, Session 1

Multi-frequency sweeping interferometry
using spatial optical frequency modulation

The multi-frequency light source such as “optical frequency comb”
has been applied to advanced white-light interferometry for surface
profile measurement and optical coherence tomography. Recently, it isdemonstrated that the interference amplitude and phase distributions
produced by sweeping of multiple frequency spacing differ fromthe white-light fringe produced by the conventional white-lightinterferometry. The high order amplitude peaks obtained by sweepingof the frequency spacing is a well-known characteristic of the multifrequency interferometry (MFI). However the characteristic that theinterference phase distribution can be controlled independently of
the amplitude distribution by shifting of the center frequency is notdemonstrated experimentally yet. We investigated the interference
phase distribution by means of a novel multi-frequency light sourcewith a spatial frequency filter (SFF) and a sinusoidal phase modulatinginterferometer (SPMI). This light source generated a quasi-opticalfrequency comb which varies the frequency spacing and center
frequency independently. The zeroth and first order interference
amplitude and phase distributions were investigated. The fixation of thephase was observed during the frequency spacing was swept and thecenter frequency was fixed. The shift of the phase was observed during
the center frequency was shifted and the frequency spacing was fixed.
The principle of MFI relating to the interference phase and the center
frequency was successfully demonstrated.

8563-4, Session 1

Simulation of real-time large-scale absolute
distance measurement with a pair of
femtosecond frequency comb lasers
Yang Li, Graduate School at Shenzhen,Tsinghua Univ. (China);
Qian Zhou, Tsinghua Univ. (China); Kai Ni, Graduate School at
Shenzhen,Tsinghua Univ. (China); Guanhao Wu, Tsinghua Univ.
(China); Xiaorui Qiao, Graduate School at Shenzhen,Tsinghua
Univ. (China)
Absolute distance measurement is essential in large-scale equipment
manufacturing and scientific projects. Nowadays, sophisticatedequipment manufacture demands for high-precision ranging with ahigh speed. Femtosecond frequency comb laser makes it possible todetermine the distance at higher precision, with its stable interval of
frequencies and wide spectral range. However, most of such systems
utilized repeat frequency scanning method to realize absolute distancemeasurement, suffering from the low measurement speed. Fortunately,
the ranging method based on a pair of femtosecond frequency comb
lasers can potentially resolve such problem.
In the method, one femtosecond laser is utilized as measurement
pulses, and another femtosecond laser with a tiny discrepancy in repeat
frequency is used to scan the return pulses. The output signals clearlyshow the phase offset caused by distance. Fourier transformation of theoutput signals gives frequencies and the corresponding phase offsets,from which we fit a straight line to calculate the distance. Theoretically,such method can realize real-time measurement. But it implies great
demands for the data processing system.
We simulated the absolute distance measurement with a pair of
femtosecond frequency comb lasers in this paper, and estimatedthe parameters of data processing system. Analyzing the result of
simulation, we gave the suitable bits and sampling frequency of ADC,
so as to improve the precision of linear fitting in data processing. And itcomes to a conclusion that slow detector with a relatively long responsetime can be adopted. The possibility of real-time measurement isdemonstrated.

Samuel Choi, Osami Sasaki, Takamasa Suzuki, Niigata Univ.
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Conference 8563: Optical Metrology and Inspection
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8563-5, Session 28563-7, Session 2

A ball bar based self-calibration techniquefor 5-axis optical measurement system

A data processing method to improve
the accuracy of depth measurement bybinocular stereo vision system

Xiaoming Du, Huazhong Univ. of Science and Technology(China) and GE Global Research (China); Jiajun Gu, GE Global
Research (China); Kevin G. Harding, GE Global Research(United States)
Micro level accuracy metrology is getting more interesting to modern
industry manufacturing, such as high end cutting tools, EDM toolingand so on. Non-contact optical measurement plays an increasing role
among industry metrology due to its efficiency on small feature andcomplex freeform surface measurement capability. System accuracy isessential to such kinds of applications.
This paper presents a ball-bar based self-calibration technique fora 5-axis point laser optical measurement system. The system iscomposed of a high accuracy laser point sensor and five motion stages
X, Y, Z, B, C. A kinematical system model of the 5-axis measurement
system is presented to map the stages and sensor readouts to thetarget position of the object to be measured. With an assumptionthat each stages’ linearity error, straightness errors, angular errors
and sensor linearity error have been calibrated or omitted due to highperformance hardware selection, the three squareness angles, laser
beam direction and rotary axis position and direction of the two rotarystages are well addressed as the model parameters in the systemmodel. Heuristic methods are introduced to separately calibrate thesystem squareness, beam direction and rotary axis by using different
data acquisition approaches over the ball bar. Parameter estimation
methods are applied to obtain the system model parameters via thedata point cloud of the ball bar. Experimental studies using cylinder bar
and ball bar demonstrate that the system achieved an accuracy better
than 5 micron.

8563-6, Session 2

A 3D measurement method and its
calibration base on the combination of
binocular and monocular vision
Dong Li, Jindong Tian, Xin Yang, Shenzhen Univ. (China)
The traditional binocular active vision measurement system consists of
two cameras and a projector, which can be regarded to two monocularvision systems composed by the projector and a camera. In this paper,
we present a three-dimensional (3D) measurement method based on
the combination of binocular vision and monocular vision. The common
field of view is reconstructed by a binocular vision system, and themissing data area is filled up by two monocular vision systems. In
order to improve the measurement accuracy and unify the three world
coordinate systems, a calibration method is proposed. The calibration
procedure consists of a binocular vision system calibration, the two
monocular vision systems calibration and a globe optimization of thethree systems for unifying to a common reference. In monocular visionsystem calibration, a new method based on virtual target is proposed
and used to set up the coordinate relations. We use a projector and two
cameras to build a vision system for testing the proposed technique.
The experimental results show the calibration algorithm ensures theconsistent accuracy in the three systems, which is important for data
fusion. And it is clear that the proposed method improves the integrityof measurement results and measuring range efficiently.

Jia Tang, Ming Zhang, Liqiang Wang, Zhejiang Univ. (China)
It is difficult to achieve accurate calibration of binocular stereo visionsystem in certain situation. When the system without accurate
calibration is used in depth measurement, large systematic errors occur
because of coarse calibration. In order to improve the measurement
accuracy, we directly calibrate the existed systematic errors after
simple calibration steps of the binocular vision system include
calibrated the camera’s focal length and the distance between two
cameras. The depths of the targets located at different distances aremeasured at three different field of views, which are center field ofview, 0.7 field of view and edge field of view. After got the original
results, the relationship between the depth errors , the field of views
and the distances is analyzed. The error curves for correction are
obtained by using the data fitting method, which are used to eliminate
the systematic errors and to get the relatively accurate data. We also
discuss the factors for causing the error. Based on image processing,a simple matching program is designed to automatically match thefeature points at left and right images, and to calculate the depth of thefeature points.

8563-8, Session 2

Emission coordinates calibration andprecision detecting of 3D measurement
systemHonggang Lu, Chunsheng Hu, National Univ. of Defense
Technology (China)
We have developped a 3 demensional deformation opticalmeasurement system, it can be used in the deformation measurementof worship and traking ship. The accuracy of measurement can achieve3?.
For precision detecting of 3-Dimensions Optical Measure System(OMS), a calibration method of auxiliary coordinate and the opticalcoordinate base on theodolites has been proposed. The installation
method of auxiliary mirrors is elaborated firstly. Installation accuracyof the auxiliary mirrors is detected. Then the influence of Axis-Error oftheodolites is analyzed under the condition of our experiment. Base on
this work the influence on the OMS’s Precision Detecting caused by themisalignment of auxiliary coordinate and optical coordinate is analyzed
and calculated. Through our experiments and analysis we find that thecoordinates alignment accuracy is no more than 10?. The measuring
range of 3-D OMS is ±3?, on these conditions the precision detecting
error of the OMS is no more than 1?. So our method is not only highaccuracy but also low requirement for the installation of auxiliary
mirrors. This method is also available for other similar work.

8563-9, Session 3

Optical profiler and its applications inindustrial measurement and inspection(Invited Paper)Dong Chen, Bruker Nano Inc. (United States)
Optical profilers have been widely used in many areas of surface
measurements and characterizations in the past 30 years. It measuresparameters such as step height, surface roughness, films thickness
in range from sub-nanometer to micrometers with sub-nanometer
resolution and accuracy. In this paper, we will present some of theapplication oriented 3D measurement techniques using optical profiler

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in both R&D lab and industrial production floor. The discussion will
target some measurement challenges encountered in optical 3D
metrology applications such as resolution enhancement, thin film
thickness with rough surfaces, dissimilar material compensation,and high aspect ratio micro-size feature measurement. The industrial
applications will include quality controls in precision machining, data
storage, HB-LED, semiconductor, lead angle, and others.

8563-10, Session 3

Absolute measurement of optical surface
profile with a Fizeau interferometer (Invited
Paper)
Osami Sasaki, Niigata Univ. (Japan); Akihiro Watanabe, Niigata
University (Japan); Samuel Choi, Takamasa Suzuki, Niigata
Univ. (Japan)
A method of absolute measurement of optical surface profile in a Fizeau
interferometer using a laser diode is proposed. Wavefront aberrationin the interferometer causes an undesirable phase distribution in theinterference signal. To eliminate this phase distribution, the object
surface is shifted in two directions orthogonal to each other and thedifference data of the surface profile of the object is obtained. Because
the undesired phase distribution does not change by the shifts of theobject surface, this phase distribution is eliminated in the difference
data which is the difference between the two phase distributions of
the interference signal before and after the shift. An absolute surface
profile is estimated by representing the object surface with a polynomial
function and by solving the difference equations with least-squares
method. The object was an 80-mm-diam flat mirror, and the shift
amount of the object surface was 4mm in the two directions. The phase
distribution of the interference signal was detected with sinusoidal
phase-modulating interferometry. The two-dimensional surface profile
was represented by a polynomial function with two variables whose
degree was less than 4. The coefficients of the terms in the polynomial
function were estimated from th difference data with least-squares
method. PV (peak-valley) and RMS (root mean square) values ofthe estimated object surface were 8.9 nm and 1.5 nm, respectively,
while their values of the reference wavefront were 46 nm and 4.3 nm,
respectively. These experimental results made clear the usefulness ofthe proposed absolute measurement method.

8563-11, Session 3

Spindle error motion measurement using
concentric circle grating and phasemodulation interferometers
Masato Aketagawa, Muhummad Madden, Shuhei Uesugi,
Takuya Kumagai, Yoshitaka Maeda, Nagaoka Univ. ofTechnology (Japan); Eiki Okuyama, Akita Univ. (Japan)
In the conventional methods to measure concurrently radial, axial andangular motions of a spindle, complicated reference artifacts withrelative large volume (for example, two balls linked with a cylinder) are
required. A simple and small artifact is favorable from the viewpoint of
the accurate measurement.
This paper describes a concurrent measurement of spindle radial,axial and angular motions using concentric circle grating and phasemodulation interferometers. In the measurement, the grating withfine pitch is installed on top of the spindle of interest. The grating isa reference artifact in the method. Three optical sensors are fixedover the concentric circle grating, and observe the proper positionsof the grating. The optical sensor consists of a frequency modulated
laser diode and two interferometers. One interferometer observes aninterference fringe between reflected light form a fixed mirror and 0-th
order diffraction light from the grating. Another interferometer observes
an interference fringe between ±2nd diffraction lights from the grating.

By the combination of the two interferometers, the optical sensor
can measure radial and axial displacements of the concentric circle
grating simultaneously. By use of the three optical sensors, three radialdisplacements and three axial displacements of the proper observed
position of the grating can be measured. From these measured
displacements, radial, axial and angular motions of the spindle canbe calculated concurrently. In the paper, a measurement instrument, anovel fringe interpolation technique by sinusoidal phase modulation andexperimental results are discussed.

8563-12, Session 3

Automated cylindrical mapper using
chromatic confocal measurement
Esmaeil Heidari, Kevin G. Harding, GE Global Research (UnitedStates)Characterization of a surface shape and finish has been vital for the
manufacture of precision parts. Overall profile, surface finish andwaviness of a part can be measured in two ways, contact and noncontact. In the contact method a stylus is dragged on the surface of apart to measure the profile and texture of the part for quantifying thesurface characteristics. Non-contact methods applied to precision
metrology include: microscopy, interferometry, chromatic confocal
microscopy and laser profiling such as structured light methods.
The chromatic confocal method offers flexibility because of its fiber
optics probes that can be manipulated to accommodate many sample
geometries. This flexibility provides a wide range of possible analysis
dimensions such as cylindrical shapes of holes and the potential toprovide both surface roughness and shape. This paper will discuss
the setup and testing of a system specifically for measuring cylindricalshaped parts and present the performance of the technology as aprecision metrology tool.

8563-13, Session 3

Imaging Stokes polarimeter by dual rotating
retarder and analyzer and its application ofevaluation of Japanese lacquer
Ryota Mizutani, Yukitoshi Otani, Tomoharu Ishikawa, Miyoshi
Ayama, Utsunomiya Univ. (Japan) and Utsunomiya Univ. Ctr. for
Optical Research and Education (Japan)
Japanese lacquer is a kind of traditional crafts. Its color is black
but there are different texture feelings because it is complicate
manufacturing process such as repeating steps of japaning andpolishing with different materials. In this report, we focus polarization
properties of surface structures of black Japanese lacquer. All
polarization states can be expressed Stokes parameters which consists
on four elements of from s0 to s3. These parameters are effective forthe evaluation of the state of polarization. As the new approach whichis evaluated the state of the surface, we visualize the polarization
information of the surface of Japanese lacquer by using a imaging
Stokes polarimeter by dual rotating retarder and anlyzer. By comparing
the degree of polarization, it is possible to evaluate the state of thesurface by visualizing of polarization information. Therefore, it can besaid that it is effective to evaluate the surface by using the polarization
information.

8563-14, Session 4

Phase shift reflectometry for sub-surface
defect detection (Invited Paper)
Anand K. Asundi, Nanyang Technological Univ. (Singapore);
Parthasarathy Sreemathy, Eden Toh, Sook May Watt, Raffles

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Girls School (Singapore); Lei Huang, Nanyang Technological
Univ. (Singapore)Sub-surface indentations in a “Magic Mirror” are used as an example
of sub-surface defect detection using various methods such as an
Optical Microscope, an Interferometer, a Laser Confocal Microscope,
the Scanning Electron Microscope and Atomic Force Microscope, and
the Phase Shift Deflectometry. The “Magic Mirror” displays an image
formed by the sub-surface indentations when the mirror is illuminatedby a beam of light such as from the sun. The indentations are formed
on a convex surface and are coated with a thin partially reflecting
transparent layer and thus no surface irregularities were detected on
the surface of the magic mirror using a standard optical microscope.
Furthermore the size of the mirror is typically around 100 mm indiameter. Thus the challenge is to measure sub-micron sized defects
below a thin layer of reflective coating on a convex surface with arelatively large diameter.
A conventional Fizeau interferometer, an obvious choice did not provide
any useful results. Since the surface of the magic mirror is convex,
the reference flat used in the interferometer was not the right choicefor the reference surface. Due to lack of other reference surfaces,
no conclusive results were obtained. A Laser Confocal System also
was unable to pick up any information - partly due to the large sizeof specimen and partially due to the defect causing the light to bereflected outside the imaging objective. The SEM and AFM were too
sensitive and measure only a very small area and thus not a suitablechoice for this detection.
However, with the use of Phase Shift Reflectometry (PSR), thesubsurface dents could be readily detected and measured. PSR issensitive to the surface slope measurement and hence can readily
detect small surface distortions. This was demonstrated in our earlier
work wherein PSR was found to be better the Phase Shift Profilometryfor dent identifications. PSR illuminates the specimen with computer
generated phase shift sinusoidal fringe patterns. The reflected patternis recorded and processed using traditional phase shift equations.
The resulting phase is then proportional to the surface slope which
can be integrated to provide the surface shape of dents. A calibrationis necessary to convert the phase information into quantitative depth
information. Preliminary analysis indicates that the indentation had
depths of the order of a few 100s of nanometers.

8563-15, Session 4

Continuous bucket creep measurement
based on moiré
Yi Liao, Robert W Tait, Kevin G. Harding, Wayne C. Hasz,
Edward J. Nieters, GE Global Research (United States)
Due to the high temperatures and stresses present in the highpressure section of a gas turbine, the airfoils, referred to as buckets,
experience creep. As gas turbine manufacturers move increasingly
toward condition-based maintenance programs whereby the life ofa component is assessed to determine its remaining life, the ability
to accurately assess creep or other failure modes becomes critical.
One approach for measuring creep is the use of moiré imaging. Using
pad-print technology, a grating pattern can be printed directly on aturbine bucket. By measuring the change in the moiré fringes, it is thenpossible to determine creep locally. This paper reviews the developmentof a prototype system and analysis software for making creep
measurements. Using a bench top camera system, measurements ofcreep in several parts have been taken. As part of these measurements,
a sensitivity analysis has been conducted to determine the influenceof noise factors on system performance. Finally, the results of creep
measurements on test bars have been compared to strain gage
measurements, and the results show good agreement between the twotechniques.

8563-16, Session 4

Circular gratings’ moiré effect for
projection measurement in volume opticalcomputerized tomography with two-stepphase-shifting method
Jia Wang, Yang Song, Zhen-hua Li, An-zhi He, Nanjing Univ. of
Science and Technology (China)
Volume optical computerized tomography (VOCT), which can realize
real 3D measurement rather than traditional 2D OCT, has greatsuperiority in quantitatively fully-field measuring the thermo physicalparameters of transient flow fields. Among the refractive index
reconstruction techniques, filtered back-projection (FBP) method
performs better than algebraic reconstruction techniques (ARTs) withhigher accuracy and computationally efficient. In order to apply FBP
to VOCT, the radial second-order derivative of projection wave front
passes through the tested phase object should be obtained firstly.
Our previous study has studied the moiré effect of circular gratings
used in projection measurement of volume optical computerized
tomography from diffraction theory. The result shows that the moiré
fringes contain the radial first-order derivative of projection wave front.
Besides, a phase shift which depends on the distance between two
gratings exists between the fringes of +1 and -1 diffraction orders.
Consequently, in this paper, a projection device with two circulargratings is established. The light passing through the tested object
and two gratings is divided into two optical paths by a prism. Two 4-f
systems are used in two paths for filtering +1 and -1 diffraction order
light and imaging respectively. Based on which, the phase shift between
moiré fringes separately obtained by two paths equal top/2 by adjusting
the distance between two gratings. Thus, based on the accurate
analytical expression of moiré fringes, a simple two-step phase-shiftingalgorithm can be used to extract radial first-order derivative distributionof projection wave front from moiré fringes.
Finally, FBP method is used to quantitatively reconstruct the 3D field.

8563-17, Session 4

High precision absolute distancemeasurement with the monolithic
femtosecond optical frequency comb
Tengfei Wu, Changcheng Institute of Metrology & Measurement(China)
The absolute distance measurement was experimentally demonstrated
by using the monolithic femtosecond optical frequency comb in air.
Our technique is based on the measurement of second harmonic crosscorrelation between reference and measurement optical pulses. The
second harmonic signal is generated from the difference frequency
principle of the monolithic femtosecond optical frequency comb,
which simplify the generation process of second harmonic crosscorrelation. The technique has some advantages, such as compact
volume, long term stabilization and low cost et al. The scheme allowing
sub-micrometer resolution in large scale measurement by using themonolithic femtosecond optical frequency comb. It will be benefit for
future lidar and satellite formation flying mission.

8563-18, Session 5

Small size probe for inner profile
measurement of pipes using optical fiber
ring beam device (Invited Paper)
Toshitaka Wakayama, Toru Yoshizawa, Saitama Medical Univ.
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The requirements of inner profile measurement of pipes and tubes
become recently larger and larger, and applications of inner profile
measurement have rapidly expanded to medical field as well as
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, optical fiber collimator and alaser diode. At this moment a probe with the size of 5 mm in diameterhas been realized.

expensive and unstable because of the mode-hop phenomenon when aconventional Fabry-Perot laser diode is used in it as a light source.

8563-19, Session 58563-21, Session 5

Fiber-optic confocal probe with an
integrated real-time apex finder for highprecision center thickness measurement ofball lenses

Towards a one step geometric calibration ofan optical coherence tomography

Armote Somboonkaew, Ratthasart Amrit, Sataporn Chanhorm,
National Electronics and Computer Technology Ctr. (Thailand);
Boonsong Sutapun, Suranaree Univ. of Technology (Thailand)
Today’s optical devices and instruments become smaller and require
high-quality optical lenses in a very compact size. Manufacturing andassembling of such high-quality lenses needs a precise quality control
for every single lens. One parameter is often measured and monitored
during production process is the central thickness of the lens. A precise
and non-contact measuring system based on optical techniques ispreferred since it does not create any scratches. Among several opticaltechniques that have been developed a fiber-optic confocal microscopy
has been widely used for non-contact measurement due to its highprecision, compact size and rapid measurement. However, for smalldiameter and large curvature lenses, high-precision instrument is not
only the key parameter to achieve an accurate measurement but also
the ability to precisely placed the instrument sensing spot at the apex
point of the measured lenses. In this paper, we developed a fiber-optic
confocal probe with an integrated camera that is used to monitor the
beam shape of the reflected light. The integrated camera functions as areal-time apex sensing device. Off-center sensing spot will produces a
non-circular image. By analyzing the beam shape of the reflected lightspot, we are able to precisely determine the location (both distanceand direction) of the focus point of the confocal probe compared tothe apex point of the measure lens within &#61617; 30 &#61549;maccuracy. To demonstrate this concept, we built the new fiber-optic
confocal probe and used it to measure the center thickness of 3-mm,
5-mm and 10-mm ball lenses.

8563-20, Session 5

Real-time displacement measurement using
VCSEL interferometer
Takamasa Suzuki, Noriaki Yamada, Osami Sasaki, Samuel Choi,
Niigata Univ. (Japan)
A displacement sensor (DS) is one of the most important devices usedin high-precision manufacturing. It monitors the thermal expansion ofa rotating spindle or ball screw, position of cutters, vibrations causedby the misalignment of rotating object, and other such parameters.
Such sensors need to be compact and robust against mechanicaldisturbances in a fabricating process.
There are many types of noncontact DSs such as ultrasonic,
capacitance, eddy current, and optical DSs. Optical DSs are easy touse, applicable to most materials, and have high accuracy. Optical DSs
are categorized into two types based on the measurement principle
used, namely, triangulation and interferometry. Because the resolutionof triangulation type DSs is inadequate, interferometry DSs are suitablefor ultraprecision machining. However, an interferometer is typically

The interferometer we propose herein uses a vertical cavity surface
emitting laser (VCSEL). It is superior in terms of the remediation of
the mode-hop issue and modulation efficiency. The interference
signal is processed with the phase-locked technique. This device
allows real-time displacement to be measured. No unstablesignals caused by mode-hop were observed in the experiments.
Displacement measurements recorded with this device indicate that it
has a measurement accuracy of 0.3 micro-m rms and 50 nm rms fordisplacements of 150 micro-m and 1.2 micro-m, respectively.

Jesús Díaz Díaz, Maik Rahlves, Leibniz Univ. Hannover(Germany); Omid Majdani, Medizinische Hochschule Hannover(Germany); Eduard Reithmeier, Tobias Ortmaier, Leibniz Univ.
Hannover (Germany)
In recent years, optical coherence tomography (OCT) has gained
increasing interest not only as an imaging system in medicine but
also as a measuring device in technical and life science applications.
A major requirement for the latter is a high confidence in the validity
and realness of the measurements. This article presents a one step
3D landmark-based geometric calibration based on the identificationof a parameterized gray-box OCT model. We introduce the complete
identification process beginning with a white- and a gray-box OCT
model for geometric distortion correction, as well as the - for thispurpose explicitly - designed and manufactured calibration standard. It
is silicon-made and consists of an array of inverse multilevel pyramidswith circular landmarks. The theoretical framework is based on a
maximum-likelihood parameter estimation finding the best suitableparameters by minimizing the error between via image processing
localized (actual) and real (target) landmark coordinates in the leastsquare sense. For evaluation purposes, common measurement
errors in the field of medical surgery such as the Fiducial Registrationand Localization Error are compared before and after geometriccalibration. Simulation and experimental results show that the proposed
methodology reduces systematic errors by more than one order ofmagnitude. These results affirm the possibility of integrating an OCT ina medical navigation system. Due to its simplicity, the calibration can be
carried out directly before a surgical intervention, thus enhancing andassuring the OCT accuracy.

8563-22, Session 5

OCT for industrial applications
Guiju Song, Kevin G. Harding, GE Global Research (UnitedStates)
Optical coherence tomography (OCT) was developed at MIT forbiomedical imaging in 1990s (1). As a technology capable of producing
high-resolution, depth-resolved images of biological tissue, OCT
was widely used for the application of ophthalmology and has beencommercialized in the market today. This is evidenced by the wide
hospital adoption, applications publication by Ocular Surgery News.
Benefiting from novel photonics components and devices, the industrial
application of the older concepts in OCT can be re-visited with respect
to the unique performance and availability. Thsi paper will introduce
the fundamental concepts of OCT and discuss its current and potential
industrial applications. Specific application of OCT to composite
inspection as an NDT tool will be discussed, including the limitations of
this method for NDT in general.

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8563-25, Poster Session

High-precision sphere diameter
determination by phase-shifting
interferometry with a frequency-tunable
diode laser
Xuejian Wu, Jitao Zhang, Haoyun Wei, Yan Li, Tsinghua Univ.
(China)The Avogadro constant is one of the promising fundamental constants
to redefine the SI basic unit “kilogram”. The most accurate method todetermine the Avogadro constant is the x-ray crystal density method,where the lattice constant, mean molar mass, mass and volume ofa perfect silicon sphere are absolutely measured. To redefine thekilogram, the relative uncertainty of the Avogadro constant shouldbe less than 2?10-8, which means that the relative uncertainty ofthe volume, the largest uncertainty source, should be reduced to
1?10-8. The silicon sphere, whose nominal diameter is 93.6 mm, is
optically polished with a roundness of less than 100 nm, so that thevolume is determined via the diameter measurement. To determine theabsolute diameter, the sphere is located in an etalon and the diameter
is obtained by subtracting the sum of the two gaps from the etalon
spacing. The gaps and the etalon spacing are measured by phaseshifting interferometry with optical frequency tuning. Nowadays, themain uncertainty sources include the laser frequency, interferogram
analysis, etalon spacing and sphere temperature. In this paper, a novel
phase-shifting interferometer is proposed to improve the diametermeasurement uncertainty. A new monolithic etalon with flat references,which is made of ultra-low expansion glass, is applied in thisinterferometer. On the other hand, a frequency-tunable diode laser iscalibrated by an optical frequency comb to generate an arbitrary single
optical frequency and the Carré algorithm is used to calculate the phase
distribution.

8563-32, Poster Session

Analysis of non-uniformity of irradiancemeasurement uncertainties of pulsed solar
simulator
Yingwei He, Limin Xiong, Haifeng Meng, Dingpu Liu, Jieyu
Zhang, Junchao Zhang, National Institute of Metrology (China)
The conversion efficiency measurement accuracy of solar cell is heavily
rely on the measurement uncertainty of pulsed solar simulator. The
measurement uncertainty assessment method of pulsed solar simulator
is widely analyzed and studied. This paper describes uncertainty
assessment method of measurement of irradiance non-uniformity
which is one of the three most important factors(spectral mismatch,
non-uniformity of irradiance and instability of irradiance) influencing
pulsed solar simulator measurement uncertainties. An experimentusing a real pulsed solar simulator was performed to testify the validityof uncertainty assessment method. The results provide a theoreticaland data basis for further analysis of overall uncertainties of solar
simulators.

8563-33, Poster Session

Calibration of optical double-triangulation
for small-size characteristics workpieces

improved in the aspects of structure and calibration in this paper. In
the structure, double camera is adopted to reduce the measuring deadzone and improve the impact of the shadow caused by inclined surfaceof the measured objects. In the calibration, the least-square curving
fitting method combined with appropriate error compensation method
is selected, based on analyses and comparisons of various calibration
approaches.
In this paper, the principle of optical triangulation method is discussed
first. The relation between the dependent variable, independent variable
and system construction parameters is nonlinear, which makes it
difficult to calibrate the optical triangulation system. A least-squarecurving fitting method is used to reduce the number of calibration
parameters and improve the calibration precision. During image
processing, appropriate filtering method is applied to preprocess
images and grey centroid method is selected to orient light spot center.
Linear interpolation method is used to reduce the fitting residual error.
At last, the source of the system error is analyzed and some methods
are proposed to ensure the precision of optical triangulation system.
Experimental results prove the effectiveness of the measuring principle
and the reliability of this measuring system.

8563-34, Poster Session

Techniques of thermal state measurement
based on blue structure light
Zhang Chi, Zhongwei Li, Yusheng Shi, Congjun Wang,
Huazhong Univ. of Science and Technology (China)
To date there hasn’t been a satisfactory solution yet for 3D
measurement for objects in thermal-state, particularly for large-sized
and complex-shaped forgings. Common automatic detection methods
include the laser beam projection, the CCD image measurement, thelaser scanning and CCD structured light measurement.
This paper proposes to use blue light projection and refit existing DMD
projector to increase the light intensity of blue channel and improve themeasurement conditions of structured light; use a single CCD camera
to reduce system cost, and acquire blue channel data through digital
filtration and Bell Interpolation; then complete the measurement of
the hot forging by the phase unwrapping algorithm of multi-frequency
heterodyne to obtain preferable experimental data.
The whole article including five parts:
1.Composition of Highlighted Blue Light Projection System
2.Principle of 3-D Structured Light Measurement
3.Adaptive Colored Plane Interpolation Algorithm
4.Three-dimensional (3-D) Reconstruction
5.Measurement Experiment and Analysis
This paper outlines the realization of high-brightness projection withblue structured light via reconstruction of the existing projector, toachieve a quick three-dimensional measurement for hot objects inthermal state. Through physical and digital filtration methods, using
the single CCD interpolation calculation and technique of temporalphase unwrapping, we can obtain the three-dimensional dynamic
data of the hot object at a temperature lower than 800°C. The
measurement is higher in accuracy, and the time of each measurement
can be controlled within 5s. The experimental facility can meet therequirements for close (about 1.5m) online measurements of thermal
state under laboratory condition or at the work site of small forgings.
By improving the brightness of the projection device, the online
measurement at the casting and forging site in harsh environment is
hopeful to be solved.

Yiguang Gu, Xiaoping Lou, Beijing Information Science &Technology Univ. (China)
In order to realize 3D profile measurement of workpieces with small-size
characteristics rapidly and precisely, optical triangulation is studied.
The measuring accuracy is affected by many factors, such as system
structure, surface characteristic of objects and the circumstance. It is

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8563-35, Poster Session

Research of linear CCD on line dynamic
detecting raw silk fineness based on FPGA
Fengjiao Liu, Zhou Wang, Soochow Univ. (China)
As a country of major raw silk production and exporter,however,thetraditional and inefficient blackboard testing has been used in current
raw silk inspection which not only affect the test impartiality,but also
greatly reduce the efficiency and accuracy. In order to enhance thecompetitiveness of raw silk in the international market, a reliablemeasuring instrument to replace the manual inspection is needed infilature industrial field.
A kind of new design scheme has been proposed that aim to realize
real time,on line raw silk diameter measurement based on linear
CCD (Charge Coupled Device) and FPGA (Field Programmable Gate
Array),which possess the advantages of non-contact,high precision,fast
response, and good compatibility etc.In this system, the samples of raw
silk are placed in parallel light which reflect light through macro imaging
is received by CCD image sensor.FPGA chip-easy to configure anduse-is selected for image signal processing,which is based on hardware
Parallel processing technology and has a high speed of operation.
FPGA is used to achieve a linear CCD driver,the video signal by the
CDS (Correlated Double Sampling) configuration and drive,FIFO (First In
First Out) memory ,data processing.
Firstly,the research on how to improve the precision of the systemfrom theoretical approach to the various functional modules parameter
optimization. What’s more,effects are solved in instability of the lightillumination and raw silk transparency,linear CCD’s dark background
imaging is chosen to avoid the bright background image easily
saturation,the distortion caused by raw silk jitter is eliminated.Lastly,system measurement accuracy reaches to±1µm.Experimental results
prove that research programme has certain feasibility and practicality.

8563-36, Poster Session

An optoelectronic system for the in-flightmeasurement of helicopter rotor blades
motions and strains
Youwei Huang, Tsinghua Univ. (China); Weizhen Cheng, Chinese
Flight Test Establishment (China); Yan Li, Tsinghua Univ. (China);
Wanxin Li, Chinese Flight Test Establishment (China)
An optoelectronic system is developed to measure in-flight the dynamic
motions and strains of blades of a helicopter. The motions of theblades, including the flapping, lag and pitch angles, are measured by
two-dimensional position sensitive detectors (PSDs) responding to
the movements of the light emitting points mounted on blades. The
dynamic strains are measured by fiber bragg gratings (FBGs). Test data
show that there are good linear relationships between angular motions
and the output voltages of PSDs. The angular error is within ±1 percent
over a wide range of flight conditions. The strains measured by FBG
are compared with that measured by strain gauge. Good agreements
are found between the two methods. The strains measured by FBG are
also reproducible, with relative deviation of only 1.22% between twice
measurements. It is concluded that the motions and strains can bemeasured accurately in flight environments.

8563-37, Poster Session

A high speed auto-adaptable system for railtrack detection
Jia Ge, Yunhan Luo, Jun Zhang, Long Guo, Liang Sun, Zhe
Chen, Jinan Univ. (China)
Security assurance work is significant in high speed railroad andtrack is the fundamental supporting part. Good imaging results areimportant for inspection of track surface defect, while image distortion
problem is frequently occurred in traditional detection systems mainly
using constant exposure frequency camera. The system introducedin this paper improves traditional systems by combining a Speed
Auto-Adaptable(SAA) system, which mainly consists of an high-speed
external controlled camera, a rotary encoder and a signal processing
card, to guarantee proper exposure frequency and uniform image
quality all the time at variable running speed. This system has a brilliant
performance in avoiding image distortion both in laboratory test andpractical application, with minimum detection precision of 0.2 mm at
relative low speed and theoretically maximum detection speed of about
400 km/h.

8563-38, Poster Session

Three-dimensional inspection andquantitative evaluation of defects in
conducting glass using optical coherence
tomography
Kung-Min Lin, Feng-Yu Chang, Kuo-En Huang, Jiann-Der Lee,
Meng-Tsan Tsai, Chang Gung Univ. (Taiwan)
Optical coherence tomography (OCT) has attracted a lot of attention
since 1991 for biomedical and other applications, due to thecharacteristics such as noninvasive measurement, high-speed imaging,and high resolutions. Furthermore, the conducting glass has been
widely used for industrial products, including display devices, solar
cells and touch panels. Until now, most proposed approaches for thedefect inspection of conducting glass are based on the mechanismof machine vision. However, this technique can only provide defectinformation on the sample surface and the defects beneath the sample
surface cannot be observed with machine vision technique. In thisstudy, nondestructive, three-dimensional imaging technique, OCT,
is implemented for optical inspection and quantitative measurementof conducting glasses, which are widely used for the commerciallyelectrical products. With the development of image processing
algorithm, the size of the defects can be quantitative evaluated from
OCT images. Furthermore, based on the phase information of the
OCT interfered signals, the displacement of the single plane can beobtained with nanometer resolution, enabling to inspect the defects ofnanostructures, which are not able to be obtained by using machine
vision technique. Additionally, an approach is proposed to modify
the 2&#61552; ambiguity of the evaluated phase. With the proposed
approach, the image artifacts can be greatly improved. Compared withmachine vision technique, OCT can be a powerful tool to provide themicrostructures at a depth range of 2-3 mm with micrometer resolution
and the nanostructures in three dimensions.

8563-39, Poster Session

Simultaneous measurements of atmospheric
NO2 and HONO using IBBCEAS with a nearultraviolet LED
Liuyi Ling, Anhui Institute of Optics and Fine Mechanics,
Chinese Academy of Science (China) and Institute of Electricand Information Technology, Anhui University of Science andTechnology (China); Pinhua Xie, Min Qin, Renzhi Hu, Nina
Zheng, Fuqi Si, Anhui Institute of Optics and Fine Mechanics,
Chinese Academy of Science (China)High sensitivity simultaneous measurements of atmospheric NO2
and HONO using incoherent broadband cavity enhanced absorption
spectroscopy (IBBCEAS) were developed. A near-ultraviolet lightemitting diode (LED) peaked at 372nm was used as light source of the
IBBCEAS instrument to measure the absorption of NO2 and HONO

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Conference 8563: Optical Metrology and Inspection
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in the spectral range of 361-378nm. The light emitted from the LED
was coupled into a 70 cm long high finesse cavity formed with two
high reflectivity mirrors and traveled back and forth between the twomirrors resulting in a long absorption path length. Mirror reflectivity
between 358 and 378nm was determined from the changes intransmitted intensity in the cavity filled with pure He and pure N2 dueto the difference between their Rayleigh scattering cross-sectionsand validated by the absorption of the oxygen collisional pair in pureoxygen in the same spectral range. The maximum mirror reflectivityof 0.99923 was found at about 369nm corresponding to a light path
length of 910 m. The air out of our laboratory was pumped into thecavity and the atmospheric absorption spectra were recorded in theabsence of atmospheric aerosols by a PTFE filter. Concentrationsof NO2 and HONO in the atmosphere were retrieved by fitting theirabsorption cross-sections to absorption coefficients deriving from themeasured absorption spectra and the average detection limits of 2.9
ppbv for NO2 and 1.2 ppbv for HONO with an acquisition time of 5
min were achieved. The results demonstrated high sensitivity of thismeasurement technique based on IBBCEAS, which is a promisingtechnique for measurements of atmospheric trace gases.

8563-40, Poster Session

Preparation and characterization of surface
oxide layer on spherical silicon substrate
Wende Liu, Chi Chen, Qiming Fan, National Institute ofMetrology (China)
Thermal oxide layer is grown on spherical surface of silicon substratewith respective radius of curvature of 84.6/96.7/120.9mm. Four nominal
thicknesses of the oxide layer, i.e., 4/10/50/100 nm, are obtained. The
substrate has a spherical surface and a planar bottom surface, bothof which are polished. It is such designed that the two sides of thesubstrate after thermal oxidation can be readily compared and the thinfilm thickness on the planar side can be used as a reference. With the
combination of ellipsometry and X ray method the thin film thickness
is characterized. The spot size of the light beam of the ellipsometer isconfigured to be as small as 0.5*0.7mm so as to minimize the influenceof the surface curvature. The calibration line between ellipsometricand X-ray data are obtained, which are compared to results obtainedon Si wafer. For characterizing the surface morphology the white lightinterferometry technique is used. Comparing with past employmentof planar Si wafer, the present approach, when applied in accurate
determination of Avogadro constant and new definition of weight,
can promisingly minimize the influence of the surface curvature toan accepted level, thus further reducing the uncertainty. Finally,
the possible application in measuring thin film on curved surface isdiscussed.

8563-41, Poster Session

Research on the video detection device in
the invisible part of stay cable anchorage
systemLin Cai, Guilin Univ. of Electronic Technology (China); Nianchun
Deng, Liuzhou OVM Machinery Co., Ltd. (China); Zexin Xiao,
Guilin Univ. of Electronic Technology (China)
The cables in anchorage zone of cable-stayed bridge are hidden within
the embedded pipe, which leads to the difficulty for detecting thedamage of the cables with visual inspection. We have built a detection
device based on high-resolution video capture, realized the distanceobserving of invisible segment of stay cable and damage detection ofouter surface of cable in the small volume. The system mainly consistsof optical stents and precision mechanical support device, opticalimaging system, lighting source, drived motor control and IP camera
video capture system. The principal innovations of the device are 1.
A set of telescope objectives with three different focal lengths are

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designed and used in different distances of the monitors by means ofconverter. 2. Lens system is far separated with lighting system, so thatthe imaging optical path could effectively avoid the harsh environment
which would be in the invisible part of cables. The practice shows thatthe device not only can collect the clear surveillance video imagesof outer surface of cable effectively, but also has a broad application
prospect in security warning of prestressed structures.

8563-42, Poster Session

Dynamic measurements by color gratings
projection method using two step Fouriertransform method
Kazuhide Kamiya, Takashi Nomura, Ami Tanbo, Kimihisa
Matsumoto, Toyama Prefectural Univ. (Japan); Hatsuzou
Tashiro, Univ. of Toyama (Japan); Shinya Suzuki, Nagano
National College of Technology (Japan)
The Fourier transform method is an analytical method for interferogramswith a spatial liner carrier. The interferograms with the spatial linear
carrier are analyzed to obtain a phase of the interferograms byeliminating the noise from shape components of the interferograms in
the Fourier domain. However, when the noise and shape components
overlap each other in the Fourier domain, it is difficult to eliminate only
the overlapped noise components by using the conventional filtering
techniques, such as the bandpass filtering. Therefore, a method is
proposed to solve these problems by using two interferograms withslightly different carrier frequencies.
In the proposed method, the Fourier transform of the twointerferograms with slightly different carrier frequencies are calculated,
respectively. Both Fourier spectra obtained by the Fourier transformof the interferograms contain same noise components. Though theFourier spectra contain the same shape components, a location of thespectra of shape components is slightly different. By calculating thesubtraction of both Fourier spectra, the noise components are removed
and inclination components are generated, because the frequency
difference between two components are small. We name the proposed
method “two step Fourier transpose method”.
The validity of the proposed filtering method is confirmed byexperiments. In the experiments, two color fringes are projected
simultaneously to scatter object. Images of color fringes are acquiredby CCD camera under the slow deformation of the scatter object. The
images are analyzed by proposed method.

8563-43, Poster Session

Multiple-pulse-train-interference-based
measurement of refractive index of air using
femtosecond optical frequency comb
Dong Wei, Kiyoshi Takamasu, Hirokazu Matsumoto, The Univ. ofTokyo (Japan)
The traceability of meter is the infrastructure for both scientific andindustrial uses. In July 2009, the national standard tool for measuring
length in Japan changed from an iodine-stabilized helium-neon (HeNe) laser to a femtosecond optical frequency comb (FOFC). How topractically perform a distant measurement that is directly linked to an
FOFC length standard tool is the most urgent challenge.
One big and basic problem of this challenge is how to achieve a highaccuracy refractive index measurement, because the length is derived
from the parameters of air. This paper is intended to give a description
to the concept, the principle, and a demonstration of a new temperaturetechnique, called multiple pulse train interference-based (MPTI) method,which was developed for a high-accuracy temperature evaluation.
The basic idea of this new technique was that water vapor pressure
was recorded based on the interference of multiple pulse trains, and200A  
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was found as a distance of a MPTI fringes by the conventional Fouriertransformation method.
A demonstration of the proposed method which is the water vapor
pressure measurement using a sealed 600-mm cell is presented. From
the result of the preliminary experiment, it has been show the possibility
that MPTI method can be used for a high-accuracy temperatureevaluation.

8563-44, Poster Session

Use of ellipsometer determine the opticalproperties of the satellite surface coatedmaterials
Yanhui Li, Zhensen Wu, Lu Bai, Xidian Univ. (China)
Ellipsometer enables to characterize optical properties of materials
and thin films quantitatively via the measurement of the ellipsometricparameters, &#61561; and D, of the reflected polarized light byspecimen. The ellipsometry surgery began to be applied to anincreasingly wide range of areas, such as physics, chemistry,materials and biology. The main advantage of the elliptical polarization
measurement technique is to measure a long time, take a large
wavelength range, the measurement angle, no damage to the sample,
measurement results are accurate. By the principle analysis of theellipsometer, In this paper, ellipsometer is used to measurement electricfield component amplitude ratio &#61561; and electric field component
phase difference D of the satellite surface coated materials, and then set
the angle of incidence and wavelength, the optical constants (refractive
index n and extinction coefficient k) and thickness can be obtained. On
the measurement results in different incident in a optimization modeling,also has access to more parameters description. The experiments
show that the measurement results and fitting results match well within
the spectral range 240nm-1200nm range. This paper is offer methodsof measurement and modeling for characterize optical properties ofmaterials and thin films.

8563-45, Poster Session

Traceable dual-frequency measurement of
Zeeman split He-Ne lasers using an opticalfrequency comb locked external cavity diodelaser
Haoyun Wei, Xuejian Wu, Lei Zhou, Jitao Zhang, Yan Li,
Tsinghua Univ. (China)
Heterodyne laser interferometer position measurement systems
provide very precise position or distance information for dimensional
measurements or motion control, and it is widely used in industrial
precision manufacture and inspection system such as the lithography.
The core component of the heterodyne laser interferometer is a dualfrequency laser, which can output two Zeeman split frequency withorthogonal polarization. The measured displacement is the multipleof the wavelength, so that the absolute frequency and its stability
are the key to keep the accuracy of the heterodyne interferometry.
For an accuracy of nanometer scales, the absolute frequency of thedual-frequency laser should be known within 10 MHz, and its relative
frequency stability should be within 1?10-9 in 1 h averaging time.
Nowadays, optical frequency combs (OFC) provide a robust andsimple way for precision optical frequency measurement traceable tothe microwave frequency standard. However, due to the characteristicof the two orthogonal polarized beams, it is not easy to measure theabsolute frequencies of the dual-frequency He-Ne laser using the
OFC directly with high SNR. In this paper, we present a new frequency
measurement system for dual-frequency He-Ne lasers using an external
cavity diode laser (ECDL). In the proposed system, an optical phaselock loop is built to lock the ECDL to a fiber-based OFC. After locking,the frequency uncertainty of this tunable, stable, and traceable ECDL

is about 2.7 kHz in 1 second averaging time. Using this ECDL, thestabilities of both the two absolute frequencies and the split frequency
are simultaneously evaluated.

8563-46, Poster Session

A new method for phase unwrapping basedigital spackle correlation
He Dong, Li Ameng, Xiaoli Liu, Xiang Peng, Shenzhen Univ.
(China)Phase aided three-dimensional imaging and metrology is increasingly
used in industrial, technical and medical applications. In thistechnology, the methods which use the projection of sinusoidal fringe
patterns have to face the problem of phase unwrapping. The common
methods for phase unwrapping e.g. by the use of multiple spatial
frequencies, temporal phase unwrapping methods, or the use of GrayCode sequences, demand to acquire added image sequences after
the wrapping phase gotten by the method of phase-shift sinusoidal
fringe. However, in some fields of application, the processing timeshould be shorter in order to reduce the number of acquiring imaging. In
order to solve the above problem we introduce the new method whichneeds less number of imaging captured. The method just needs tocapture four phase shifting images and a digital spackle map projectedby projector and acquired by cameras. The wrapping phase can beassured from the above four phase shifting images, mean while, thecorrelation of each pixel and the projected digital spackle map gotten
from the above digital spackle map. We can ensure the wrapping ordersof each pixel of camera with the correlation and get the unwrapping
phase.

8563-49, Poster Session

Geometric calibration and accuracy
assessment of multispectral imager on UAVs
Fengjie Zheng, Tao Yu, Xingfeng Chen, Jiping Chen, Guoti
Yuan, Institute of Remote Sensing Applications (China)
Accurate geographical positioning data is critical to UAV quantitative
remote sensing research. MCC4-12F, the first UAV multispectral
imager in the domestic, is equipped with fisheye lens, a computercontrolled ﬁlter wheel and a CCD plane array detector. The approachto perform multispectral imaging is optical ﬁlters to separate theelectromagnetic spectrum into several passbands. However, somesystematic deformations appeared since the optical path is slightly
different for image acquisition. Unknown intrinsic parameters and lens
optical distortion of the camera will cause serious image aberrations,even leading a few meters or tens of meters errors in ground per pixel.
So accurate calibration is necessary for fully assessing corrected
images. In this paper, a method on physical model of comprehensive
geometric calibration in a 3D test field has been developed andempirically tested using images collected with MCC4-12F. Using spaceresection algorithm to assess the geometric calibration parameters ofthe multispectral imager. Then evaluating the accuracy by calculating
object space and image point coordinate differences, analyzing impact
of different photogrammetric altitudes. Practical geometric accuracy
was obtained in Tianjin UAV flight experiments, in order to verify theaccuracy and reliability of the calibration parameters. The results
showed that theoretical precision were 0.57mm and 0.43mm, object
space RMSE were 0.2 and 0.14 pixels in X direction and in Y direction.
Image point RMSE was superior to 0.5 pixels. The corrected accuracy
validated by ground checkpoints was less than 0.3m.Therefore, theapproach presented here was suitable for UAV multispectral imager.

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8563-50, Poster Session

8563-53, Poster Session

Technology of optical azimuth transmission

Analysis of solving the point correspondence
problem by trifocal tensor for real-timephase measurement profilometry system

Honggang Lu, Chunsheng Hu, National Univ. of Defense
Technology (China)
In consideration of practical application, the principal of several typical
optical azimuth transmission methods are presented. A systematicallysummary of azimuth transmission method is made for the first time.
Four typical methods including Theodolite (including gyrotheodolite)
collimation method, Camera series method, Optical apparatus for
azimuth method and polarization modulated light transmission method
are presented. For these typical azimuth transmission methods, theiressential theories are elaborated. The devices, the fields and limitationsof these typical methods’ are introduced. Theodolite (including
gyrotheodolite) collimation method is used in the ground assembly of
spacecraft. Camera series method and optical apparatus for azimuth
method are used in azimuth transmission between different decksof ship. Polarization modulated light transmission method is used inazimuth transmission of rocket and guided missile. At the last, thefurther developments of these methods are discussed.

8563-51, Poster Session

Device testing the corner precision ofphotoelectric shaft angle encoder
Guanyu Wen, Shuang Wang, Changchun Univ. of Science andTechnology (China)
To improve efficiency of testing the angle precision of photoelectric
shaft encoder,an device can greatly increase the detection efficiency inthis paper. and adjust according to actual test detection accuracy. This
device used the laser auto-collimation lightpipes and polyhedron,thecomputer control testing process and dispose the data, directly display
test results. Through analysis the test system characteristic and data,find some cause of error factor.

8563-52, Poster Session

Algorithm research of high-precision opticalinterferometric phase demodulation basedon FPGA
Chunxiao Zhi, Xiaojun Zhang, Jinghua Sun, Harbin Engineering
Univ. (China)
Optical interferometric phase demodulation algorithm is provided
based on the principle of phase generated carrier (PGC), which canrealize the optical interference measurement of high-precision signal
demodulation, applied to optical fiber displacement, vibration sensor.
Modulated photoelectric detection signal is performanced by interval
8 frequency multiplication sampling. The samples calculate the phasemodulation depth and phase error through a feedback loop to achieve
optimum working point control. On the other hand the results ofsampling calculate precision of numerical of the phase. The algorithm
uses the addition and subtraction method instead of correlation
filtering and other related complex calculation process of the traditional
PGC digital demodulation, making full use of FPGA data processing
with advantage of high speed and parallel; At the same time, theoperating speed of the algorithm increases by optimizing the number ofsampling points. The experimental results show that: the algorithm of
demodulation phase resolution up to 6 ?rad, dynamic range better than
190dB, can run in FPGA as the core system. The algorithm is suitable
for application to optical precision measurement such as high-precisiondisplacement, vibration, magnetic field. The demodulation system canget higher speed and precision of measurement.

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Kai Zhong, Zhongwei Li, Yusheng Shi, Congjun Wang,
Huazhong Univ. of Science and Technology (China)
With the advancement of DLP technology and powerful hardware,
the real-time measurement system based on phase measurement
profilometry (PMP) principle has been extensively studied recently.
Phase unwrapping for finding point correspondence between cameras
or camera and projector is the key technology for 3D calculating in
PMP system. In our system three-step phase-shifting algorithm whichallows minimum image recording number is used to obtain wrapped
phase-map, and our point corresponding method based on trifocal
tensor constrain can be directly implement on wrapped phase-map.
But many factors can lead to false correspondence, such as numberof fringes, images noise, system non-linear response. This paper givea detail analysis on how these factors will affect the point matchingprocess and a feasible method is proposed to reject error candidate
points. Furthermore this method is characteristic of pixel-independent,
which can speed up by parallel computing technique for real-time
applications. Finally this method indicates a good performance in theexperiment.

8563-23, Session 6

Industrial surface finish method comparison
for fine finish measurements (Invited Paper)
Kevin G. Harding, Esmaeil Heidari, Robert W. Tait, GE Global
Research (United States); Guangping Xie, Zirong Zhai, GE
Global Research (China)
Measurement of surface finish in industrial manufacturing has
traditionally been done by means of either visual comparison withreference plates or by the use of contact stylus based profilers. There
are many challenges associated with contact profilers such as stability
during measurement in an industrial environment, damage and wearof the tip, measurement in tight spaces or on curved surfaces andjust the limited amount of data obtained by a linear scan of the stylus.
Many alternative methods have become available such as white lightinterferometry, focus based systems, and even laser scatter. This paper
will present the result of testing of the commercially available methods
with particular emphasis on the fine surface finishes demanded intoday’s manufacturing, then present some alternative methods thatshow strong potential to address some of the challenges mentioned
above that are not in wide use today. The analysis will specifically
explore some of the physical mechanisms that affect the stylus
based measurement, as well as the limitations of many of the optical
approaches related to view angle and diffraction limited resolutionconsequences. The area of confocal imaging method will be spedifically
explored as how it might be used to obtain more complete data on veryfine surface finishes.

8563-24, Session 6

Application of non-contact optical methods
for microscale surface metrology
Shihua Wang, A*STAR National Metrology Ctr. (Singapore)
Micro Systems Technologies (MST), MicroElectroMechanical Systems(MEMS) and Micromanufacturing have become synonymous withthe design, development, and manufacture of very small devices
and systems. Besides continuing effort in developing MEMS-based
manufacturing techniques, the latest effort in micro-manufacturing
is also applicable to non-MEMS-based manufacturing. Research

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and technological development in related field is encouraged by theincreased demand on surface metrology of micro-components to bepromised development in the scaling down of the traditional macromanufacturing processes for micro-length-scale manufacturing.
This paper will introduce micro-scale surface metrology at the National
Metrology Centre using non-contact optical methods, specifically on
the development of a large scanning range laser confocal microscopefor calibration and measurement of micro-structures. These structures
include dimensional and component surface functional parameters suchas material removal/wear, bearing area, cutting tool edge, laser marking,micro-channel in microfluidic device, lens array mould, surface flatness/deformation of super-low reflection (less than 2%) coating surface,
low reflection rock surface etc. Corresponding measurement working
principle and system design & configuration will be discussed. In
addition, some typical applications of laser & white-light interferometry
for measuring micro-surface deformation of micro-beam in MEMS
accelerometer, membrane in microphone and surface of micro-mirror
will also be discussed.

8563-26, Session 6

Image detection of inner wall surface ofholes in metal sheets through polarization
using a 3D TV monitor
Takamasa Suzuki, Katsunori Nakano, Shogo Muramatsu,
Niigata Univ. (Japan); Toshiro Oitate, Totsuka Metal Industry
Co., Ltd. (Japan)
An automated inspection system needs to be introduced for sheetmetal working in order to reduce the production cost. For thispurpose, we plan to configure a suitable system that uses optical andcomputerized image processing techniques.
Although a digital camera is a suitable imaging device for this purpose,it captures unnecessary images of the inner hole surface of a hole(hereafter, referred to as the hole surface) in a thick test target. At times,
it is difficult to distinguish between the surface of the target and thehole surface. Hence, the unnecessary hole surface images only serve tofurther complicate the image processing that requires to be performed
for edge detection.
We propose an effective technique for optically detecting the holesurface image using the polarization property of a 3D television (TV)monitor. In our technique, a digital camera is used to capture, usinga polarizer, an image of the test target placed on the surface of thescreen of a TV monitor. The polarized light emitted by the TV monitor
illuminates the hole surfaces present in the test target placed on thescreen of the monitor. When the polarizer placed in front of a camera
lens is adjusted such that the camera captures a dark image for thetransmitted light, only the highlighted hole surfaces are visible inthe captured image because the light scattered at the hole surfaces
is depolarized. This reduces the complexity of performing image
processing for edge detection.

8563-27, Session 6

Simultaneous measurement of birefringencemagnitude and direction using Wollaston
prism
Longhai Liu, Aijun Zeng, Beishi Chen, Lexing Zheng, Huijie
Huang, Shanghai Institute of Optics and Fine Mechanics (China)
Measurement of the birefringence magnitude and/or direction attracts
many research interests. In existing polarization element rotating
methods, the background light and the intensity fluctuation affect themeasurement accuracy. For instrumentation, a method of measuring
the birefringence magnitude and direction using Wollaston prism ispresented.

The light source is a semiconductor laser, whose intensity is sinusoidally
modulated. The modulated beam passes through a circular polarizer,
the sample and is then split into two sub-beams by a Wollaston
prism, whose transmission axes are 0º and 90º. The two sub-beams
are detected by a bi-cell detector. The two detected signals are thenfiltered to get two alternating current signals. Then the Wollaston prismis rotated by 45º, whose two transmission axes are 45º and 135º, andthe other two alternating current signals are obtained. By processing
the four alternating current signals, the birefringence magnitude anddirection can be resolved independent of the intensity.
In experiments, a wedge wave plate was laterally moved to changebirefringence magnitude in the range of 0º~90º. Then the process
was repeated at different birefringence direction. The measured
birefringence magnitude and direction coincide with the nominal values.
The standard deviation of the birefringence magnitude is less than
0.12º. The maximum deviation of the birefringence direction is less than
0.61º. The usefulness of the method is verified.

8563-28, Session 6

Extended depth of field for visual
measurement systems
Yanyu Zhao, Yufu Qu, BeiHang Univ. (China)
The field of view of visual measurement systems in the direction of
optical axis is determined by the depth of field. While the focus of visual
measurement changing from final quality assurance to process test,
larger depth of field and faster test speed are becoming increasingly
demanding. Therefore, an extended depth of field method based on
liquid lens and computational imaging is presented in this paper. The
method applies a liquid lens to sweep its focus length within a single
detector exposure time, and then a blurred image is obtained throughthe capturing process. The blurred image is restored to an extended
depth of field image based on computational imaging technology.
Three contents are included in this paper. First, in the optimizationof the optical system, the liquid lens is added to the conventional
imaging objective in visual measurement systems, which results inextended depth of field and a nearly constant magnification. Second,
the parameters of image acquisition such as the range, speed and timeof the liquid lens sweeping and the integration time of the detector, arecarefully designed to assure high signal-to-noise ratio and high contrast
in visual measurement systems. Third, by modeling the imaging
system, we gain the point spread function, after which a deconvolution
technique is applied, using the blurred image to restore an extended
depth of field image. Experiment results demonstrate that our method
can extend the depth of field of the visual measurement system for over
10 times, while the change of the magnification within the depth of fieldremains less than 1%.

8563-30, Session 7

Temporal phase retrieval in dynamic speckle
interferometry by adaptive emperical mode
decomposition
Hao Zhang, Tianjin Univ. (China)
As a promising technique, temporal phase analysis has been applied
to dynamic speckle measurement. In temporal phase analysis, aninterferogram sequence is obtained by a high speed camera during
object movement. And the phase is extracted from the temporal phase
map.
Hilber transform based analytic algorithm is not trival with noisy phasemap. And the EMD(Empirical Mode Decompositon) algorithm can be
performed to put the signal into an appropriate shape for accuratepahse computation.
Generally EMD algorithm produces several modes in which only one
would be used in phase computation. Traditional approaches would
chose the first IMF, which however is not correct.

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This paper proposed an algorithm to automatically determin the modethat best fits the shape of input signal. In experiments, the performanceof our algorithm was shown.

8563-31, Session 7

Holographic approach to detection ofdelamination areas in layered polymeric
waveguides by means of strain solitons
Irina V. Semenova, Galina V. Dreiden, Ioffe Physico-TechnicalInstitute (Russian Federation); Karima R. Khusnutdinova,
Loughborough Univ. (United Kingdom); Alexander M.
Samsonov, Ioffe Physico-Technical Institute (RussianFederation)
Laminated structures are widely used now in a wide variety of
constructions. The proper functioning of such structures has vital
importance especially in automotive and aerospace industries. The
major problem in their behaviour is a possibility of a sudden andirreversible delamination caused by various factors. We propose andstudy a NDT approach to investigate the dynamics of prolonged layered
structures based on the propagation and optical (holographic) detectionof bulk strain solitons in them.
Being formed, the soliton propagates along the homogeneous wave
guide with almost no change of amplitude, shape and velocity. In
inhomogeneous wave guides the soliton parameters vary, depending
upon parameters of inhomogeneities. We analyze variations inthe soliton behaviour in layered wave guides caused by thin cuts,
representing delamination, and show that the bulk nonlinear solitaryelastic strain waves may provide an opportunity to check quickly thedelamination areas even in prolonged layered wave guides.
We present results on experimental observation of the evolution of
bulk solitary waves in polymeric 2- and 3-layered waveguides withglassy and rubber-like adhesives used for bonding. Soliton evolution
in long delaminated waveguides was recorded using the techniqueof holographic interferometry. Delamination areas of different length
were introduced to study variations in soliton parameters. Variationsof soliton amplitude were shown to demonstrate the existence ofdelamination areas. The formation of complex wave patterns - soliton
trains or radiating solitons became an additional evidence of defects inlayered waveguides.

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Nanophotonics and Micro/Nano Optics
Monday - Wednesday 5 –7 November 2012
Part of Proceedings of SPIE Vol. 8564 Nanophotonics and Micro/Nano Optics

8564-1, Session 1

New directions for microcavity physics
Kerry J. Vahala, California Institute of Technology (UnitedStates)Over the last ten years there has been remarkable progress in boosting
quality factor (Q-factor) in micro and millimeter-scale optical resonators.
Chip-based devices have attained Q factors of nearly 1 billion andmicro-machined crystalline devices have provided Q factors exceeding
100 billion. The resulting long, energy-storage times combined withsmall form factors have made it possible to access a wide range of
nonlinear phenomena, and has led to new science such as cavity
optomechanics. I will review some of these results including opticalfrequency microcombs, opto-mechanical cooling to the quantum
ground state and mechanical amplification by stimulated emission ofphonons. Prospects for new technologies will also be discussed.

8564-2, Session 1

Advances in electrically pumped lasing from
Ge-on-Si (Invited Paper)
Jurgen Michel, Rodolfo E. Camacho-Aguilera, Yan Cai, Lin
Zhang, Marco Romagnoli, Lionel C. Kimerling, Massachusetts
Institute of Technology (United States)
Monolithically integrated lasers on a silicon platform have long been
a desirable addition to on-chip photonic systems. However, until
recently the only viable solutions were based on bonding III-V based
semiconductor lasers on silicon waveguides. Several years ago,
Germanium (Ge) has been suggested as a gain material for lasingthat can be monolithically integrated into a Silicon CMOS flow. Morerecently, optically pumped lasing has been demonstrated using tensile
strained, n-type Ge as the gain medium. Here we will present anelectrically pumped Ge laser, using n-type doped Ge with an active
carrier concentration above 4e19cm-3. The Fabry-Perot laser produces
more than 1 mW output power and exhibits lasing in a wavelength
range from 1520nm to 1700nm. We will discuss the implications of amonolithic lightsource on Si as well as present the most recent results.

8564-3, Session 1

Calculation for gain coefficient dependence
on donor density of n+-Ge with considering
Auger recombination
Koki Takinai, Kazumi Wada, The Univ. of Tokyo (Japan)
Recently, Ge has attracted strong attention as a gain material for lightemitting devices which are compatible with Si-CMOS technology
and lasing was achieved by using Fabry-Perot resonator and in situ
doped Ge with above 1x10^19 cm^(-3). However, lasing by Ge using
micro-cavity structure has not achieved. Since micro-cavity has larger
scattering and radiation loss than Fabry-Perot, increasing the material
gain of Ge is much important to achieve lasing by using several
techniques such as quantum dots, tensile-strain and heavily n-type
doping. Heavily doping is a promising way and it is eagerly studied how
to obtain heavily n-type doped Ge, however, Auger recombination getsincreased according to doping level and should be dominant abovea specific carrier density, which means there is the most appropriate
doping density. We calculated the material gain coefficient of n+-Ge
dependence on donor density with considering the decrease of carrier
density contributed to Auger recombination. Although the parameters
are difficult to determine, Auger coefficient of 1x10^(-30) cm^(6)s^(-1), spontaneous radiative coefficient of 1x10^(-10) cm^(3)s^(-1) andcarrier injection of 1x10^(19) cm^(-3) were assumed. As a result, there
was a peak at about 2x10^(20) cm^(-3) and gain coefficient started todecrease from the point according to the increase of donor density. The
peak did not present for calculation without Auger recombination andshould be equivalent to the most appropriate donor density under theabove assumption. The peak position should shift by the change of theparameters for recombination, so the peak can be at several 10^(19)cm^(-3).

8564-4, Session 1

Strain induced bandgap and refractive index
variation of silicon
Jingnan Cai, Yasuhiko Ishikawa, Kazumi Wada, The Univ. ofTokyo (Japan)
Real time compensation to the temperature fluctuation is on demandfor photonic devices applications and the introduction of strain on
photonic devices might be a solution. Thus it is necessary to study
the strain effect on the behaviors of photonic structures. In this report,a simple flexible structure of silicon micro-beam is designed for theinvestigation of strain effects on the photonic cavity structures. A finite
element simulation shows that by simply bending the silicon microbeam, strain can be generated on the beam and more than 2.5%of strain can be reached. Experimentally, silicon micro-beams with
2.5 ?m in width and 15 ?m in length and 250 nm in thickness were
fabricated to check the optical behaviors of the micro cavity understrain. The photoluminescence measurement results indicate that withthe strain applied, the silicon bandgap can be adjusted from 1.12 eV toabout 0.84 eV. A red-shift of Febry-Perot resonance peak can also be
observed to reach up to 18 nm, which is related to a significant 1.4%
change of refractive index. Those results prove that by adjusting thestrain in the micro cavity, the bandgap as well as the effective refractive
index of the micro cavity can be effectively controlled and hence thecompensation to temperature fluctuation can be achieved. Our study
also demonstrates that rather than other factors, the large changeof silicon bandgap and refractive index are induced by the strain.
This work indicates that the application of strain in silicon could be a
promising way for many photonic applications based on the adjustmentof bandgap and refractive index.

8564-5, Session 1

Photoluminescence andelectroluminescence of erbium yttrium andytterbium co-doped Er silicates
Xingjun Wang, Zhiping Zhou, Peking Univ. (China)
In recent years, Erbium (Er) silicates and Yttrium (Y) and Ytterbium(Yb) co-doped Er silicates have attracted intensive investigations dueto their efficient luminescence at 1.53µm. The potential applications
are monolithic integrated light emitters or optical waveguide amplifiers
for silicon photonics. Compared with traditional Er-doped materials,
the Er concentrations of silicates are about 1 to 2 orders of magnitude
higher due to the stoichiometric nature of these Er compounds. Highgain or strong light emissions may be achieved. Moreover, the Er
concentrations of silicates can be easily continuously changed throughY- or Yb co-doping, which is necessary to reduce the deleterious effects
for 1.53µm gain and luminescent efficiencies, such as the concentrationquenching and up-conversions due to the neighboring Er ions. The Yb
co-doped Er silicates have another advantage than the Y co-dopingthat is the sensitization effect of Yb for Er, which can enhance theexcitation efficiency of Er. In this paper, we summarized our group

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Conference 8564:
Nanophotonics and Micro/Nano Optics
recent work about ErYb/Y silicates. We fabricated three kinds ofwaveguide structure, the strip-loaded, slot and hybrid ErYb/Y silicateswaveguides, and the optical amplification was observed in thesewaveguide structures. In addition, 1.53µm electroluminescence (EL) in
ErYb silicates was also realized using hot carriers’ impact excitationsof Er ions. The current conduction behavior, EL emissions, and impact
excitation cross sections were studied
This work was supported by the Peking University’s 985 startup project
and National Natural Science Foundation of China Grant No. 60907024.
1. R. M. Guo, X. J. Wang, K. Zang, B. Wang, L. Wang, L. F. Gao, Z.
Zhou, Appl. Phys. Lett. 99, 161115, 2011.
2. R. M. Guo, B. Wang, X. J. Wang, L. Wang, L. Jiang, and Z. Zhou, Opt.
Lett., 37, 1427, 2012.

and linewidth narrowing of the spectra clearly indicate that stimulated
emission was obtained. This result is a precursor to obtain nanotubebased laser. Carbon nanotubes have then be integrated in silicon
structures to develop a new class of optoelectronic devices. A complete
study was carried out which led to the demonstration of the s-SWNTs
absorption and emission coupling with evanescent silicon waveguides
at a wavelength of 1.3 µm. The emission intensity at the device output
was temperature-independent. These results open the door to thedevelopment of a new type of silicon photonic devices based on carbon
nanotubes.

8564-8, Session 2

4. B. Wang, R. M. Guo, X. J. Wang, L. Wang, L. Y. Hong, B. Yin, L. F.
Gao, Z. Zhou, Opt. Mater., 34, 1289, 2012.

Photophysical properties of dendrimer
phthalocyanine–functionalized single-walledcarbon nanotubes

8564-6, Session 1

Hongqin Yang, Dandan He, Dongdong Ma, Yuhua Wang,
Jiangxu Chen, Shusen Xie, Yiru Peng, Fujian Normal Univ.
(China)3. L. Wang, R. M. Guo, B. Wang, X. J. Wang, and Z. Zhou, IEEE. Photo.
Tech. Lett., 24, 9000, 2012.

Emission and optical gain properties of Si
slot Er_xY_2-xSiO_5 waveguides
Hideo Isshiki, Takayuki Nakajima, Takuya Sato, The Univ. ofElectro-Communications (Japan)
High index contrast Si-based slot waveguide is one of key technologies
for the heterogeneous integration on a Si chip. The strong opticalconfinement to the low-index slot, such as ErxY2 -xSiO5, is expected
for guided TM mode. The confinement effect leads to the modificationof the optical mode density, resulting in the enhancement of radiativetransition. We have fabricated planer Si-slot waveguides with ErxY2xSiO5 slot layers in order to demonstrate the dependence of theradiative emission on guided waveguide modes. The PL fine structure
particular to Er2SiO5 crystal has been observed through the waveguidestructure. We confirmed the enhancement of the TM mode edge
emission, and the intensity was about two times higher than thatof TE mode. We also demonstrate the fabrication of Er0.4Y1.6SiO5
waveguide slotted into Si photonic crystal. Strong optical confinement
for the C-band is confirmed. 30dB/cm modal gain is achieved in thisdevice by VLS method.

8564-7, Session 2

Carbon nanotubes on silicon for lightemission (Invited Paper)
Laurent Vivien, Nicolas Izard, Adrien Noury, Institutd’Électronique Fondamentale (France); Etienne Gaufres, Univ.
de Montréal (Canada); Xavier Le Roux, Institut d’ÉlectroniqueFondamentale (France); Richard Martel, Univ. de Montréal(Canada); M. Tange, Toshi Okasaki, National Institute ofAdvanced Industrial Science and Technology (Japan)
Single wall carbon nanotubes (SWNTs) have generated a growinginterest for several years due to their carbon based 1D structure.
The metallic part of them (m-SWNT) as well as the semiconducting
part (s-SWNTs) is more and more considered for their future use in
microelectronics as electrode or transistor channel. For few years,
s-SWNTs are also considered for photonic applications due to their
tunable direct band gap in the NIR: optical telecommunications,
datacoms and biosensing. To exploit their optical properties, wehave developed an efficient technique which selectively extracts
semiconducting-SWNTs. These high purified s-SWNTs allow a strong
enhancement of the photoluminescence properties at 1.3µm and1.55µm. These advances led to the first demonstration of optical gainin carbon nanotubes of about 180cm-1 at the wavelength of 1.3µm.
The presence of energy threshold in the photoluminescence signal

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Single Carbon nanotubes (SWNTs) are very promising materials forpolymer composites, energy conversion, sensing and biologicalapplications. However, processing SWNTs and integrating them into realapplication is severely limited by a number of inherent shortcomings
such as purification, manipulation and lower solubilities in organic
solvents. To improve their solubility and overcome the aggregation,
various functionalization strategies including covalent and noncovalentmethods, have been explored. Incorporation of light absorbing antenna
dendrimer phthalocyanine through a covalent and/or noncovalent
linkage with the extended ? electron of a carbon nanotube could
constitute an ideal supramolecular nanoassembly for generating singlet
excited energy and its conversion to chemical energy. In this paper, thephotophysical properties of these two novel dendrimer phthalocyanine–functionalized single-walled carbon nanotubes were studied bysteady-state fluorescence, time-resolved fluorescence and Raman
spectroscopy. The effect of dendron generations on the photophysicalproperties was compared. Furthermore, the photoinduced electrontransfer of these two dendritic phthalocyanine-functionalized carbon
nanotubes was studied and compared. The carbon nanotube served
as an electron acceptor and the dendritic phthalocyanine served
as an electron donor. This study showed that the new dendritic
phthalocyanine-functionalized carbon nanotubes could be utilized forsubcellular localization and designed as molecular transporters.

8564-9, Session 2

Visibility of few-layer graphene
Yi-Hao Wang, Guan-Huang Wu, Ya-Ping Hsieh, Hsiang-Chen
Wang, National Chung Cheng Univ. (Taiwan)
Graphene has emerged to be an exciting material with potential
applications. A remarkable feature of graphene is that it is a Dirac solid,
with the electron energy being linearly dependent on the wave vector
near the crossing points in the Brillouin zone. It also exhibits unusual
fractional quantum Hall effect and conductivity behavior. The discoveryof the fascinating properties of single-layer graphene has generated
much interest in the physical and materials sciences. To distinguishgraphene layers become a very important issue. Using the discriminant
for each location of the RGB pixel, then calculate the colors of thegraphene layers; it can distinguish the different layers of the image
thought multi-spectral imaging technology. Therefore this method cansave time for material characteristics measurements, such as Raman,
TEM, and AFM. We quickly determine the layers of graphene samples
from a microscope image.

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8564-10, Session 2

New design of As2Se3-based chalcogenide
photonic crystal fiber for ultra-broadband,coherent, mid-IR supercontinuum generation

We report on the manufacturing of various photonic devices including
antennas, photonic crystals, and large resonant arrays by direct milling,including many made in Gold.?Results of feature sizes <10 nm, on
highly topographic samples, of 3-dimensional structures and of longterm processes are presented. Thus the benefits of ion beam patterningand especially the added capabilities of IBL are discussed.

Rim Cherif, Amira Baili, Mourad Zghal, SUP’COM (Tunisia)
As2Se3 chalcogenide photonic crystal fibers (PCF) exhibit highnonlinearities and present a waveguide suitable for generating
broadband supercontinuum (SC) for many applications such as fiber
lasers, pulse compression and multi-wavelength optical sources. The
optical properties of the fundamental mode in the PCF are accurately
calculated in terms of chromatic dispersion, effective mode area andnonlinear coefficient.
In this paper, a new design of PCF is presented by increasing the ratio
between d2 the diameter of the second ring and d1 the diameter of theinner ring surrounding the core. For the optimization of our structure
we fixed &#61516; to 1 µm and considered different ratios of d2/d1
varying from 0.8 µm to 0.88 µm by steps of 0.02 µm. The proposed fiber
possesses an ultra-flattened dispersion curve over a wide wavelength
range. The generated SC in such fiber is investigated, which has flatand smooth profile, covers a broad range. We examine the interplayof the nonlinear effects that lead to the construction of the SC as afunction of the injected energy and the fiber length. We have found a
bandwidth over two octaves coherent SC extending from 2 to 8 µm,
by pumping at &#61548;p=5 µm, 100 fs pulses with a relatively low
energy of E=200 pJ in only 5 mm fiber length. Supercontinua generation
was mainly attributed to the four wave mixing and the self-phasemodulation. The significance of this work is that it provides a new typeof mid-infrared coherent SC source with flat shape and broad band.

8564-11, Session 2

Direct patterning of high-resolution andlarge-area photonic devices by various
unique ?ion- beam lithography approaches
Andre Linden, Raith Asia Ltd. (Hong Kong, China); Sven
Bauerdick, Achim Nadzeyka, Raith GmbH (Germany)
Focused ion beam (FIB) systems and combined FIB-SEM microscopes
are widely used for sample preparation and various analytical tasks.
With the addition of a dedicated pattern generator and lithography
software package, these microscopes are applied to some
nanopatterning tasks increasingly utilising the focused ion beam as
the primary technique. However, given the SEM/ microscope platform
supports a tilting stage offering only micro meter positioning accuracy
and poor repeatability, nanopatterning applications are usually limited tosimple patterns over small areas within one field of view.
Materials like Gold – being very popular for applications inphotonics and optics – include special challenges from an ion beamnanopatterning point of view. Due to the very large sputter yield it isdifficult to achieve small feature sizes, high aspect ratio structures
and a minimum lateral damage. The latter is due to Gold being highly
intolerant to collateral beam (tail) damage. On one hand this is a main
reason for photonic devices to fail and on the other hand it is a goodtest for high quality ion beam properties.
Here a novel IBL tool (Ion Beam Lithography, Raith ionLiNE) has beenused which overcomes nanofabrication specific limitations of analytical
FIB microscopes by utilising a dedicated lithography architecture andan ion column and source optimized for high resolution and large
area nanopatterning, over high current performance. This includes inparticular a laser interferometer stage, high beam to sample stability as
well as enhanced beam current stability, excellent deflection accuracy
and true automation capabilities (e.g. for additional positioning
correction). These system features resolve the trade-off between
the need of high resolution and long patterning time, i.e. by setting
up automated over-night processes small currents of only a few pA
become applicable to large patterns enabling improved resolution.

8564-12, Session 2

Sequential phonon excitation in cavity
optomechanical system
Xue-Feng Jiang, Yun-Feng Xiao, Peking Univ. (China)
Whispering-gallery-mode (WGM) microcavities, with ultrahigh Q
factors and small mode volumes, have attracted increasing interests inextensive applications, e.g., low-threshold lasing [1], nonlinear optics[2], cavity electrodynamics [3-4], cavity optomechanics [5] and miniaturesensing [6-7]. Photon circulating in this type of microresonators greatly
enhances the energy density inside the microcavities, providing a
possible way for the study of the radiation pressure induced mechanicaloscillation of the cavity material, i.e., the optomechanics. Once themechanical oscillation modes are excited, they can couple withthe photonic modes of the microresonators. Optomechanics is aninteresting phenomenon and it provides a platform for the study ofmechanical cooling, macro-quantum states, light storage and otherpotential fields. Traditional technique to study cavity-optomechanics islocking the laser wavelength to the cavity mode. However, it’s complex
to operate and hard to excite the high order sideband mode which isimportant in cooling and heating because pump laser wavelength is
far away from the sideband resonant wavelength. Here in this work
we report an experimental observation and theoretical analysis of thesequential muti-phonon excitation in an optomechanical system inwhich a high-Q WGM microtoroid cavity coupled with a fiber taper. With
the low-pass filtering, we separate the fast-varying and slowly-varying
processes and derive a very clear picture of multi-phonon emission.
We present an experimental observation of sequential phonons
emission in an optomechanical system in which a high Q whisperinggallery microtoroid coupled with a fiber taper. Coupling between
the phonon modes and the photonic modes leads to more than one
resonance dip in the transmission spectrum. It is found that, withincreasing input power or taper-cavity coupling strength, more andmore phonons can be excited. This may constitute a new way ofcontrolled photon-phonon interaction and is potential for realization of a
new class of RF oscillators.

8564-13, Session 2

The effect of aperture layout design on
the multi-GHz operation of light-emitting
transistors(Invited Paper)
Chao-Hsin Wu, Peng-Hao Chou, National Taiwan Univ. (Taiwan)
The base current plays a key role in the transistor since its discovery(16 December 1947, Bardeen and Brattain). The base current (IB)separates the low impedance input (emitter) from the high impedance
output (collector), thus yielding a “transfer resistor.” Recently, III-V
semiconductor material has been fabricated as a heterojunction bipolartransistor (HBT) which can operate as a high speed device. The HBT
can be modified and operated as a three-port light-emitting device(an electrical input, electrical output, and a third port optical output)
by incorporating one or more quantum wells in the base region, thus
becoming a heterojunction bipolar light-emitting transistor (LET). In
the present work, we have designed different sizes of emitter diameter
DE and base diameter DB of InGaP/GaAs LETs in aperture layout
design. Through different layout designs, the LETs exhibit different
electrical current gain (?= ∆IC/∆IB) and optical light output due to207A  
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Conference 8564:
Nanophotonics and Micro/Nano Optics
different carrier recombination processes in the transistor base region.
By reducing the lateral emitter size from 18 to 13 ?m, ? increases dueto the higher injection current densities and better confinement of
the radiative recombination in the base region. However, ? decreases
when reducing the base diameter from 31 to 22 ?m with fixed emitter
diameter. The effective carrier recombination lifetime can be estimatedfrom dc analysis and rf measurement (small-signal modulation). We
have obtained multi-GHz spontaneous light modulation of LETs, and thedevice performance is closely related to different layout designs withdifferent device parasitics.

8564-14, Session 2

Theory of phonon assisted secondary
emission from a semiconductor quantum dot
in the regime of vibrational resonanceAnvar Baimuratov, National Research Univ. of Information
Technologies, Mechanics and Optics (Russian Federation);
Ivan D. Rukhlenko, Monash Univ. (Australia); Anatoly V.
Fedorov, National Research Univ. of Information Technologies,
Mechanics and Optics (Russian Federation)
We develop a low-temperature theory of phonon assisted secondary
emission from a semiconductor quantum dot, the electronic subsystemof which is resonant with the confined longitudinal-optical phononmodes. Our theory employs a generalized model for renormalizationof the quantum dot’s energy spectrum, which is induced by thepolar electron-phonon interaction. The model takes into accountthe degeneration of electronic states and allows for several LOphonon modes to be involved in the vibrational resonance.With theseresults, we solve the generalized master equation for the reduced
density matrix, in order to derive an expression for the differential
cross section of secondary emission from a single quantum dot. The
obtained expression is then analyzed to establish the basics of optical
spectroscopy for measuring fundamental parameters of the quantum
dot’s polaron-like states.

8564-18, Session 3

High-performance silicon optical modulators(Invited Paper)
Graham T. Reed, David J. Thomson, Frederic Y. Gardes,
Youfang Hu, Nathan Owens, Univ. of Southampton (United
Kingdom); Kapil Debnath, Liam O’Faolain, Thomas F. Krauss,
Univ. of St. Andrews (United Kingdom); Leon J. Lever, Zoran
Ikonic, Robert W. Kelsall, Univ. of Leeds (United Kingdom);
Maksym Myronov, David R. Leadley, The Univ. of Warwick(United Kingdom); Igor P. Marko, Stephen J. Sweeney, David
C. Cox, Univ. of Surrey (United Kingdom); Antoine Brimont,
Pablo Sanchis, Univ. Politècnica de València (Spain); GuangHua Duan, Alban Le Liepvre, Christophe Jany, Marco Lamponi,
Dalila Make, Francois Lelarge, Alcatel-Thales III-V Lab. (France);
Jean-Marc Fedeli, Sonia Messaoudene, CEA-LETI (France);
Shahram Keyvaninia, Gunther Roelkens, Dries Van Thourhout,
Univ. Gent (Belgium)
In this work we present results from high performance silicon opticalmodulators produced within the two largest silicon photonics projects
in Europe; UK Silicon Photonics (UKSP) and HELIOS. Two conventional
MZI based optical modulators featuring novel self-aligned fabrication
processes are presented. The first is based in 400nm overlayer SOI
and demonstrates 40Gbit/s modulation with the same extinction
ratio for both TE and TM polarisations, which relaxes coupling
requirements to the device. The second design is based in 220nm
SOI and demonstrates 40Gbits/s modulation with a 10dB extinction

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ratio as well modulation at 50Gbit/s for the first time. A ring resonatorbased optical modulator, featuring FIB error correction is presented.
40Gbit/s, 32fJ/bit operation is also shown from this device which has
a 6um radius. Further to this slow light enhancement of the modulation
effect is demonstrated through the use of both convention photonic
crystal structures and corrugated waveguides. Fabricated conventional
photonic crystal modulators have shown an enhancement factor of
8 over the fast light case. The corrugated waveguide device shows
modulation efficiency down to 0.45V.cm compared to 2.2V.cm in
the fast light case. 40Gbit/s modulation is demonstrated with a 3dB
modulation depth from this device. Novel photonic crystal based cavity
modulators are also demonstrated which offer the potential for low fibre
to fibre loss. In this case preliminary modulation results at 1Gbit/s aredemonstrated. Ge/SiGe Stark effect devices operating at 1300nm arepresented. Finally an integrated transmitter featuring a III-V source and
MZI modulator operating at 10Gbit/s is presented.

8564-19, Session 3

silicon waveguide devices for photonic
networks-on-chip (Invited Paper)
Lin Yang, Ruiqiang Ji, Jianfeng Ding, Rui Min, Institute of
Semiconductors (China)
With chip multiprocessor continuously requiring more communication
bandwidths, metallic-based electrical networks-on-chip (NoC)
gradually becomes the bottleneck for improving the performanceof chip multiprocessor due to its high power consumption, limited
bandwidth and long latency. Silicon-based photonic networks-on-chipis considered as a potential solution to overcome the limitations of its
electrical counterpart.
A series of optical devices are required to construct the opticalinterconnect between two processor cores, such as lasers, modulators,
multiplexers, waveguides, de-multiplexers and detectors. Such a pointto-point interconnect is the simplest communication mode. However,for network application environment, the processor core is required
to communicate with many processor cores. This function is usuallycompleted by optical router, which is located at each node of photonic
networks-on-chip and connects the local processor core with theneighboring nodes.
In this talk, we will review the status of silicon waveguide devices forphotonic networks-on-chip and introduce our efforts on these topics.
In the first section, we will introduce several critical issues for designing
an optical modulator for photonic networks-on-chip. Following
these guidelines, we demonstrate a 40 Gbps Mach-Zehnder opticalmodulator with the extinction ratio of 15 dB. In the second section, we
will introduce the guideline for designing an N-port optical router forphotonic networks-on-chip. Several five-fort optical routers for Meshphotonic networks-on-chip have been demonstrated. By utilizing theperiodic filtering property of microring resonator, the data transmission
rate is expanded to 100 Gbps for single channel.

8564-20, Session 3

Non-reciprocity in silicon from dynamic
modulation (Invited Paper)
Shanhui Fan, Stanford Univ. (United States)
Optical isolators, which suppress all backreflections, are of fundamental
importance in large-scale optical information network. Achieving
optical isolators on-chip is therefore of great importance for the future
developments of silicon photonics. To achieve complete opticalisolation, one needs to break time-reversal symmetry or reciprocity.
Thus, it is well known that any structures that are linear and static, andthat are constructed from materials having a symmetry permeability
and permittivity tensor, can not behave as a isolator. In this work, weshow that dynamic modulation of silicon structures can function as
an effective isolator that reproduces all functionality of conventional

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magneto-optical devices. We further show that the phase of themodulation can introduce an effective gauge potential for photons,
opening new optical physics for the manipulation of light.

8564-21, Session 3

Active nanoplasmonics (Invited Paper)
Anatoly V. Zayats, King’s College London (United Kingdom)
Recent advances in nanofabrication and subwavelength opticalcharacterisation have led to the development of a new field of
nanophotonics concerned with routing and conditioning of opticalsignals in scalable and integratable devices. In this context, surface
plasmons, the electromagnetic excitations coupled to collective
motion of conduction electrons near a metal surface, are emerging
as a new optical information carrier that enables signal manipulationand processing on the subwavelength scale. Both surface plasmon
polaritons and localised surface plasmons provide the electromagnetic
field confinement and enhancement and ability to engineer dispersion
by controlling nanostructure parameters. Plasmonic metamaterials play
crucial role in the development of novel paradigms such as negativerefractive index engineering, superlensing and optical cloaking.
In this talk we will discuss various realisations of plasmonic components
for enhancing performance of conventional photonic devices such as(O)LEDs, VCSELs and sensors as well as for development of integrated
nanophotonic circuits with particular emphasis on active functionalities
such all-optical and electro-optical modulation and amplification ofplasmonic signals and dispersion management. These functionalities
facilitate possible applications of plasmonics in telecommunication
networks, integrated photonics and lab-on-a-chip systems.

8564-22, Session 4

Si photonic crystal waveguide based delaylines (Invited Paper)
Ray T. Chen, The Univ. of Texas at Austin (United States)

slower than c/100. This kind of devices offers promising applications in
nonlinear optics.

8564-24, Session 4

Reducing radiation losses of onedimensional photonic-crystal mirrors in asilica waveguide
Wei Ding, Rongjuan Liu, Zhiyuan Li, Institute of Physics (China)
One-dimensional PhC mirrors are constructed in a single-mode silica
slab waveguide with a row of elliptical holes, whose photonic band gap
can be quickly attained by eigen-mode calculations. Putting eyes onradiated waves rather than guided modes, we point out that component
radiated waves only occur at the interfaces between the feeding
waveguide and the PhC mirror section when propagating guided waves
impinge on these interfaces. When component radiated beams overlap
spatially, the total radiation loss of the PhC mirror periodically oscillateswith the increase of the device length. We visualize this process by asimple picture and estimate the total radiation loss via an analyticalmodel. For uniform PhC mirrors, the results of our model agree wellwith the simulated results in terms of the oscillation period of the total
radiation loss, the damping of the oscillation, the initial phase of theoscillation, and the relative intensity of the radiation loss. We further
investigate non-uniform PhC mirrors and find that, in contrast to thewell-known “impedance-matching” picture, a progressively taperedtransition from the feeding waveguide to the PhC mirror does notyield the lowest radiation loss. This surprising result embodies theinterferometric nature of the radiation process in a low-index waveguideand clarifies the route of the widely reported “radiation recycling”
phenomena. As the refractive index of the waveguide increases, thephotonic band gap of the PhC mirror becomes deeper, the interference
between component radiated beams gradually diminishes, and the“impedance-matching” picture revives.

8564-25, Session 4

No abstract available.

Giant dispersive properties of planar gradedphotonic crystals

8564-23, Session 4

Charles CAER, Xavier Le Roux, Eric Cassan, Institutd’Électronique Fondamentale (France)

Engineered slot-comb photonic crystal
waveguides
Charles Caer, Xavier Le Roux, Eric Cassan, Institutd’Électronique Fondamentale (France)
Slow light in photonic crystal waveguides exhibits peculiar features
which provide substantial benefits for enhanced light-matterinteractions. It increases the optical path length and the local intensityof light, meanwhile loss issues can be addressed by dispersion
engineering of the guided mode. However, silicon nonlinearities arestrongly limited by nonlinear losses (e.g. multi-photon absorption, free
carrier absorption). This limitation can be overcome when introducing
a slot filled by a highly nonlinear material. The slot further provides astronger confinement of light. We extend the concept of slot photonic
crystal waveguides by structuring the slot into a comb, forming Comb
Photonic Crystal Waveguides (CPCWs). As reported in our previous
works, we show that this comb enhances the light confinement at thenarrowest parts. We perform dispersion engineering of the comb toachieve structures supporting high group index bandwidth product,
and validate our design by FDTD calculations to study the couplingissue. We then measure the transmission in devices fabricated with
80kV e-beam lithography process. We perform cut-back measurements
to investigate the losses, showing that CPCWs have losses arecomparable with those of a standard W1 photonic crystal waveguides.
Our measurements in a Mach-Zehnder Interferometer allow us to
extract high group indices values, enabling us to measure waves

The dispersive properties of planar photonic crystals (PhCs) havebeen envisaged for years. In particular, the superprism effect has
been considered to obtain a strong influence of input beam conditions(e.g. wavelength or input angle) on the light group velocity direction,
enabling the design and fabrication of on-chip infra-red spectrometers
and integrated optical demultiplexers. We extend here the propertiesof PhCs to the study of graded photonic crystals (GPhCs) made ofa two-dimensional chirp of lattice parameters and show that GPhCs
enable solving several drawbacks of dispersive PhCs like the beam
divergence issues or the need of long preconditioning regions toprecompensate beam diffraction effects. The proposed approach isapplied to a square lattice air-hole PhC with a gradual filling factor thatwas fabricated using e-beam lithography and ICP etching techniques. A
0.25µm/nm spatial dispersion is demonstrated for a 60µm square GPhC
structure in the 1470-1600nm spectral range without noticeable spatial
or spectral spreading. Moreover, contrary to PhC superprism structures,a linear dispersion is obtained in the considered wavelength range. It isenvisioned that similar GPhC structures could be also used in the midinfrared wavelengths.

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Conference 8564:
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8564-26, Session 4

The temperature influence on thetransmission character of a LC full-filled PCF
Jialu Wang, Yongjun Liu, Xiaoqi Liu, Weimin Sun, Harbin
Engineering Univ. (China)
Two kinds of full-filled photonic crystal fibers (PCFs) are investigatedby experiments. All the air holes of the index-guide photonic crystal
fibers are filled with liquid crystal (LC). The light power is launchedfrom the other end of the index-guide photonic crystal fibers. One endof the photonic crystal fibers which is not filled with liquid crystal wasconnected to the light power, and a part of photonic crystal fiber at theother end was filled with liquid crystal. The filling length of liquid crystal
is nearly 5cm. Based on the same test conditions, experiments werecarried on the two kinds of photonic crystal fibers. The full-filled partwas heated to different temperatures to test the transmission characterof the full-filled photonic crystal fibers. When the temperature increased
from 30° to 60°, the output light spot gradually turned from a bright spot
to a dark one and then faded away. When at 66°, the spot disappeared
entirely. At the same time, the whole spectrum also moved towards tothe shorter wavelength. After that, the output light power reappeared
and became an entire different spot compared to the former spot when
the temperature continued increasing. The experiments show that when
the temperature is blew 66°, the two kinds of fibers have the same
performances, but once the temperature is higher than 66°, different
phenomena will appear. The reappeared output light spot of smaller air
holes presents a circle spot, while the spot of larger air holes shows aring.

8564-27, Session 4

Optical properties of azo-chromophore
attached on the surface of silica photonic
crystalKwang Sun Kang, Kyungil Univ. (Korea, Republic of)
Optical properties of a azo-dye attached on the surface of themonodisperse silica photonic crystal have been investigated. The
azo-chromophore was covalently attached to a 3-isocyanatopropyl
triethoxysilane (ICPTES) having isocynate functional group by aurethane bond formation reaction. The resulting disperse red/ICPTES(DRICP) was attached on the surface of the silica photonic crystal
by hydrolysis and condensation reactions. The FTIR spectrum of
the resulting product DRICP/silica sphere (DRICPSS) shows nocharacteristic isocynate absorption peak at 2270 cm-1 and shows a
new absorption peat at 1700 cm-1 corresponding the C=O stretchingvibration. This result indicates the complete reaction between -N=C=O
and -OH. The DRICPSS has weak brownish color when it is dried.
The color of the DRICPSS changed to intense red when it is wetted
in methanol, ethanol and 2-propanol. The near infrared absorption
maximum at 788 nm shifted to 718 nm for the ICPDRSS after wetting inmethanol. This system can be applicable to a sensitive alcohol sensor.

8564-15, Session 5

Si micro- and nano-structures forcommunication and energy applications(Invited Paper)
Ching-Fuh Lin, Shih-Che Hung, Shu-Chia Shiu, Hong-Jhang
Syu, National Taiwan Univ. (Taiwan)
Si is one of the two most abundant materials on earth. In the past
decades, Si has been the most important material for electronics. Thus
it is also highly desired to use Si for applications in other areas. Here we
report the use of Si micro-structures for optical-communications andSi nano-structures for energy applications. Sub-micron Si waveguides
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is fabricated on (100) Si substrates using laser reformation technique.
This method helps solve the incompatible problem for the integrationof optics and electronics on a single Si chip. The typical thickness ofthe oxide layer on the CMOS transistor layer is below 100nm which,however, creates excessive optical loss due to the light coupling into
Si substrate, so conventional Si-photonics need thick-oxide layer. Thus
we develop laser reformation technique. High-power pulse laser isused to melt high-aspect ratio Si ridges from regular (100) Si waveguideand form circular-profile structure. Subsequently, thermal oxidation
is implemented to oxidize the reformed structure, preventing opticalloss due to light coupling to the substrate. For energy applications, Sinanostructures are fabricated using the metal-assisted chemical etching(MacEtch) technique. Si nanostructures could greatly reduce the surface
reflection to enhance light harvest. In addition, Si nanowires are further
combined with organic materials to form hetero-junction solar cells
using low-cost solution process. Furthermore, the Si nanostructures
and MacEtch process are refined to form completely single-crystal
Si thin film. Thus the material cost of Si solar cells can be potentiallyreduced to only 1/10 of current ones.

8564-16, Session 5

Brilliant and tunable color by changing pore
diameter of metal-coated porous anodic
alumina
Jiawen Li, Ping Deng, Zhiqiang Zhu, Wenhao Huang, Univ. of
Science and Technology of China (China)
Porous anodic alumina (PAA), with highly ordered microstructures,
has attracted much attention due to some unique physical and opticalcharacteristics. In recent years, PAA is also used to obtain different
colors by methods such as growing nanowires, tuning pore depth,or sputtering metal on PAA surface. In this paper, we report a simple
and precisely controllable method to tune color by changing the pore
diameter of PAA. In order to obtain PPA with different pore diameter,
we first prepare the PPA membrane by anodization of high purity
aluminium foil in acidic solutions in a two step procedure and thenimmerse the fabricated PPA membrane into phosphoric acid to enlarge
pore diameter. The different pore diameters of PAA with same depth arecontrolled by changing the second anodization time and immersed timein phosphoric acid. After sputtering metal on surface of PAA, the brilliant
color can be seen on the surface of PAA. Different colors of PAA filmwith metal-coated are obtained using this method and colorful patterns
are successfully fabricated. The physical models of the original andsputtered PAA are set up and the parameters of model are analyzed
by Finite Difference Time Domain (FDTD) method, and the details of
the color tuning method are further proposed. It is concluded that thecolor can cover the whole visible range using this method and color
saturation is related to thickness of sputtering metal. This method will
have potential use in decoration, color displays and anti-counterfeiting
technology.

8564-28, Session 6

Nanowire-based solar cells (Invited Paper)
Xiuling Li, Univ. of Illinois at Urbana-Champaign (United States)
Integrating III-V with silicon (Si) through direct growth at the chip levelhas been one of the holy grails of III-V semiconductor devices, because
it provides opportunities to realize integrated electronics and photonics
systems and enable high efficiency multijunction tandem solar cells.
The biggest barrier has been that III-V and Si semiconductors do nothave the same lattice constants or thermal expansion coefficients, andtherefore cannot be stacked on top of each other in a straightforward
way without generating dislocations. Because of this, multijunction
tandem solar cell structures often consist of layers with graded
compositions through metamorphic growth, which inevitably results inlower material quality.
Vertical one-dimensional (1D) nanowire (NW) geometry, on the other

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hand, allows a lot more freedom from lattice-matching requirements
by dissipating the mismatch strain energy through the vast surface
areas. In this talk, we report the realization of ternary III-V (InxGa1-xAs
or GaxAs1-yPy) NWs on Si and other substrates in a wide composition(energy) range through direct heteroepitaxy using metalorganic chemical
vapor deposition (MOCVD). We demonstrate monolithically grownaxial and radial p-n junctions in the III-V NWs, the interband tunneling
diode junctions, as well as the improvement of solar cell efficiency byincorporating III-V NW structures in a planar Si cell.
Nanowire based solar cells fabricated using metal-assisted chemical
etching (MacEtch) method will also be presented.

8564-29, Session 6

Morphology effects on the performance of
flexible polymer solar cells under bending
Liqiu Men, Qiying Chen, Memorial Univ. of Newfoundland(Canada)Polymer solar cells have been actively pursued recently for theiradvantages of mechanical flexibility and low cost, which offer the
possibility for coating onto flexible substrates, the prerequisite for rollto roll processing. However, the fabrication of multiple layers on flexible
substrates exhibits significant technological challenges. In this study,
we perform morphology observation of a nanostructured polymer bulk
heterojunction flexible solar cell and the effect of morphology change
on its photovoltaic performance upon bending. The photovoltaic
device consists of poly(3-hexylthiophene) (P3HT) as a donor and[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) as an acceptor,
which are prepared on flexible plastic substrate of polyethylene
terephthalate (PET) with one of the highly conductive polymers ofpoly(3,4-ethylenedioxythiophene): poly(styrenesulfonate (PEDOT:PSS)(for example, PH510) as the anode. We investigate the photovoltaic
performance of the flexible solar cells in comparison with solar cellsof standard configuration. In particularly, we study the morphology
changes of the devices to reveal the effects of physical distortion of
the cells on the photovoltaic performance of the devices. Morphology
observation performed with scanning electron microscopy (SEM)
indicates that the quality and morphology of the films become worse
after bending with more cracks at significant bending. The SEM imagesof the individual layers of the device reveal that the morphologies of
the PH510 and Al layers are significantly influenced by the bending
effect. The photovoltaic performance of a flexible solar cell gradually
decreases as the bending angle decreases.

8564-30, Session 6

Mid-infrared chalcogenide photonics (Invited
Paper)
Juejun Hu, Hongtao Lin, Yi Zou, Lan Li, Okechukwu Ogbuu,
Univ. of Delaware (United States); Sylvain Danto, J. David
Musgraves, Kathleen Richardson, Clemson Univ. (United States)
and Univ. of Central Florida (United States)
Chalcogenide glasses, namely the amorphous compounds containing
sulfur, selenium, and/or tellurium, have emerged as a promisingmaterial candidate for integrated photonics given their wide infraredtransparency window, almost infinite capacity for composition alloying,as well as high linear and nonlinear indices. This talk will review ourrecent progress on the processing and characterization of integrated
photonic devices based on chalcogenide glass materials. We haveshown that high optical quality glass films can be prepared using
both traditional vacuum deposition as well as emerging solution
derived techniques, enabling an entire array of unconventional device
architectures both at the telecommunication wavelengths as well as in
the 3-6 micron mid-infrared band. The examples include low-loss midinfrared glass waveguides and resonant cavities on silicon, and robust
tunable photonic devices on a flexible substrate platform. We further

demonstrate that these photonic devices constitute the basic building
blocks for novel ultra-sensitive chemical sensors with single molecule
detection capability, and high performance thermal imagers operating atroom temperature.

8564-17, Poster Session

A simple and cost-effective method for
fabricating antireflection structure using
self-agglomerated metal nanoparticle asetching mask
Xiaoxuan Dong, Su Shen, Renjin Shao, Linsen Chen, Soochow
Univ. (China)
Broadband antireflection property is significantly important for many
optoelectronic devices, such as solar cells, flat panel displays, andcharge coupled devices. Optical interference film stack has been
widely used to reduce the reflection on the interface. However, film
stack usually works in a specific wavelength bandwidth range and its
performance deteriorates with increasing incident angle. Moreover,the material used for coating is limited and thermal mismatch between
different coating material is an issue in fabricating such devices. With
the rapid development of nanofabrication process, antireflection
devices with nanocale have drawn more and more scientists’ attention.
The nanostructure-based antireflection devices, with nanopillars,
nanocones, nanospheres or nanoholes, can not only increase thetransmission efficiently, but also improve the spatial and spectral
dispersion characteristics. There are many methods to fabricate
such devices, such aselectron-beam lithography, laser interference
lithography, and nanoimprint lithography etc. Nevertheless, thementioned approaches suffer from low effeciency, time-consuming andexpensive and complicated equipments and processes.
In this paper, a simple and cost-effective method to fabricate
antireflection device based on nanoholes was proposed. The mainidea is the combination of wet-chemical deposition of silver layer andphysical etching on Si substrate. After the wet-chemical deposition, a
rapid thermal annealing treatment at the 200°C-400°C was well done
form separate Ag nanoparticle islands owing to the self-agglomerated
phenomenon. And then etch the sample with Ag nanoparticle byutilizing ICP technique, in this step, Ag nanoparticle acted as a mask of
etching Si substrate. By controlling the etching parameter and etchingtime, the high performance antireflective structures were achieved. The
relationship between each element of experiment and measuring results
were further analyzed and discussed.

8564-56, Poster Session

Photonic crystal one-way delay waveguide
Hongliang Ren, Hao Wen, Jia Li, Yali Qin, Zhejiang Univ. ofTechnology (China); Weisheng Hu, Chun Jiang, Shanghai Jiao
Tong Univ. (China)
It is of fundamental important for the coupling between waveguidemodes and micro-cavity modes in an integrated optical system basedon photonic crystals (PCs). By means of this resonator coupling,
channel drop filters (CDF), splitters, switches, and other integrated
optical devices can be built. In addition, the micro-resonator systems
are developed to control the delay time of optical pulses by many
researchers because the realization of all-optical signal processing
relies on the ability to delay or store optical pulses. Recently, a PCs
one-way waveguide with broken time-reversal has been proposed by,which is similar to the chiral edge states of electrons in the quantum
Hall effect. Based on the one-way waveguide, the nature of waveguidecavity coupling interaction is fundamentally adjusted. We design
optical delay lines based on a photonic crystal one-way waveguide,
which consists of some point-defect micro-cavities side-coupled toa photonic crystal one-way waveguide. According to the coupledmode theory in time, the transmission spectrum is discussed, and it is

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Conference 8564:
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demonstrated that the theoretical result maintains a unity transmission
spectrum throughout the entire resonant frequency. Subsequently,
the numerical result is calculated by using the finite element method(FEM), which agrees well with the theoretical analysis. As a pulse witha Gaussian profile is launched at the entrance of the waveguide, thestructure is calculated by using the finite element method (FEM), and
it is verified that the structure can control the delay of optical pulses.
Compared with the optical delay lines by introducing the perfect electric
conductor (PEC) slabs in the photonic crystal one-way waveguide, thedevices have a wavelength-selective characteristic, which are of greatsignificance in optical buffer applications.

8564-57, Poster Session

Analysis of relations between anti-reflective
properties and silica structures
Yukun Zhang, Lifang Shi, Qiling Deng, Institute of Optics andElectronics (China); Jinglei Du, Sichuan Univ. (China); Xiaochun
Dong, Shaoyun Yin, Chunlei Du, Institute of Optics andElectronics (China)
The paper compares the antireflective properties of three familiar silica
structures at the range of the wavelength from 400 nm to 750 nm. The
relevant results by finite-difference time-domain method demonstratethat the pyramid array possess the lowest reflection with the same
parameters in other structures. Reflection on the structure surface issuppressed effectively resulted from changes in the reflective indexcaused by variations in the structure height. The reflective index
gradient decides the reflection on antireflective structures. In moststructures, reflection is stronger than that on the pyramid array, whichis affected by the duty ratio on the substrate surface. The pyramidarray possessing relatively large duty ratio rather than others canapply sequential reflective index gradient. Therefore, reflection on the
pyramid array would be smaller than the other structures. Moreover,
the relations among reflection, transmission, and the wavelength havebeen calculated. The reflection is attenuated with the structure heightincreasing. When the height is above 200 nm, reflective attenuationon the structure surface gradually gets damped. It indicates thatthe pyramid array with the height above 200 nm has the better
antireflective properties, which is the useful guidance to fabrication of
the antireflective structures.

8564-58, Poster Session

Infrared stop-band filter based on a
subwavelength structure
Yanqin Song, Chinhua Wang, Yiming Lou, Bing Cao, Soochow
Univ. (China)
In this paper, we propose stop-band filter in infrared region using aperiodically chirped subwavelength structure. The subwavelength
structure is made of a stack of metal and Ge pattern made on a
thick metal layer that is deposited a Si substrate. It is found that an
appropriately designed microstructure of metal-insulator-metal patches
can generate a wideband infrared absorption, resulting in an infraredstop-band filter. Different metallic patch widths existed in a period
generate trough in the reflection spectrum at different wavelengths. The
full width at half magnitude (FWHM) of the stop-band filter can thus beadjusted by tuning the patch width. The larger the metallic patch width,
the wider the bandwidth. The rejection depth of the stop-band wascontrolled by the metallic and dielectric materials employed and also
the thickness of the materials. Under the condition of subwavelength
dimension of the structure compared with the working wavelength,
it is found that a FWHM of 4um at central wavelength of ~10um and
85% isolation depth can be achieved if Cu or Ag grating structures are
employed. The results are obtained by FDTD numerical calculation.
The proposed structure is helpful to the design of wideband efficient
plasmonic absorbers in infrared or THz spectral regions.

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8564-59, Poster Session

Effects of grating marks on lithographyalignment precision
Jiangping Zhu, Song Hu, Institute of Optics And Electronics(China); Junsheng Yu, Univ. of Electronic Science andTechnology of China (China)
In proximity lithography alignment, the method based on moiré fringes,
its alignment marks consists of two sets of line gratings with slightly
different periods, which are respectively etched on mask and wafer.
The relative positions between mask and wafer are analyzed by phaseof moiré fringes. And phase of moiré fringes are extracted by Fouriertransform method. This alignment technique is capable of determining
simultaneously alignment offset of x,y directions and is characterizedby high accuracy, high reliability and easy operation, etc. But, therational design of alignment grating marks parameters for this approachto realize high-precision alignment is of great importance. In order toboost the feasibility of moiré fringes alignment method, effects of a few
physical parameters of grating marks on alignment accuracy are deeply
investigated by theory reasoning as well as numerical calculation. The
results imply that parameters of grating marks, such as period size andratio, have an important influence on alignment scope and accuracy.

8564-60, Poster Session

Beam splitter with tunable power ratio by acomposite structure
Kun Ren, Tianjin Univ. (China); Xiaobin Ren, Tianjin Univ. of
Science and Technology (China)
Photonic crystals (PhC) that are periodic dielectric structures are proved
to be excellent candidates for controlling an electromagnetic wave.
The defects introduced in a perfect photonic crystal can confine theflow of light. Additionally, complex spatial dispersion properties of PhC
structures provide mechanism to steer light. The propagation direction
is given by the group velocity that is perpendicular to the equalfrequency contour (EFC) of the PhC. In this paper, we present a new
method to modulate the direction of wave propagation.
We gradually modify the orientation of dielectric rods in a photonic
crystal to investigate the propagation of light. The engineered PC withgradient constitutive parameter in a specific direction is called gradedphotonic crystal. The continuous bending of wave has been realized.
The light guiding relies on the gradual variation of the direction of thegroup velocity during propagation. The ability to shape the EFC by the
structure gradient offers a new way to design optical devices.
A new beam splitter is then designed with a composite constructed by
two graded photonic crystals. We find that the incident beam is divided
into two output beams by the designed splitter. A Y-shaped beam
splitter is achieved. The splitting ability of the beam splitter is discussed
further. We demonstrate the power ratio of the two beams can be
adjusted easily by changing the location of the input beam.

8564-61, Poster Session

Bending the light by a gradually modulated
photonic crystal
Xiaobin Ren, Tianjin Univ. of Science and Technology (China);
Kun Ren, Tianjin Univ. (China); Mingcheng Guo, Tianjin Univ. of
Science and Technology (China)
Due to their ability to manipulate light at the wavelength scale andtheir promise in ultra-compact integrated optical circuits, photonic
crystals (PhC) have attracted much attention. Straight or bent defect isintroduced in a perfect photonic crystal to confine the flow of light. The
routing of light depends on the existence of photonic band gap. In this

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article, we present a study on the guiding of light by modifying spatial
dispersion property of PhC.
Light transport is studied by the use of finite-difference time-domain
technique. It’s shown that within a frequency window the non-diffraction
light propagation can occur. This kind of propagation behavior depends
on the self-collimation effect originated from flat shaped dispersion
surface of the PhC. The propagation of light under different orientation
angle and ellipticity of ellipse is investigated in detail. We find that theorientation of ellipse has an effect on the propagation direction. The
degree of controlling light can be tuned by changing the ellipticity.
The simulated results are analyzed from the point of equi-frequency
contours. Based on the above results, we propose a method tocontrol the flow of light by the use of the graded ellipse rod in PhC.
We demonstrate that gradually varying the orientation angle of ellipse
can result in smooth change in the light propagation direction. The
beam redirection relies on gradual modifications of the PhC structure
parameter that gradually change its dispersive properties. This provides
a promising way toward designing optical devices for spatial beam
routing. We believe that our results suggest a new direction for therealization of photonic crystal light circuits.

8564-62, Poster Session

Pulsed laser deposition of zincnanostructures and their nonlinear opticalcharacterizations
Yasaman Golian, Asma Motamedi, Mohammad Reza Rashidian
Vaziri, Fereshteh Hajiesmaeilbaigi, Univ. of Tehran (Iran, Islamic
Republic of)
The field of nanostructured materials has been widely recognized
as one of the most promising and rapidly emerging research areas.
Optical nonlinearity of metallic nanostructures has attracted muchattention because of their fast nonlinear response that can be utilized
in making them as potential optical devices. In this work, we report on
preparation of Zinc nanostructures using the pulsed laser deposition
technique. We have used a Nd:YAG laser (532 nm, 20 ns FWHM and
10 Hz repetition rate) as the ablation source. The laser fluence on thesamples was about 1.5 J/cm2 and a base pressure of 2e-5 Torr wasmaintained during the depositioning process. The laser ablation waslasted for 30 and 45 min. The linear absorption spectra of the samples
were obtained using a UV-Visible spectrometer. Optical absorption
spectra show absorption peaks around 297 nm, due to the surface
Plasmon resonance (SPR) of Zn nanoparticles. The morphology andthe mean size of nanoparticles in the prepared nanostructured films
were obtained by Atomic Force Microscopy. The nonlinear absorption
coefficient and the nonlinear refractive index of the films were
determined using the standard Z-scan technique. To this end, the input
beam of a CW Nd:YAG laser (532 nm, 160 mW) was focused by a 19.5
cm lens to obtain a peak intensity of 4.42?103 W/cm2 at the focus.
Our measurements indicate positive signs for the nonlinear opticalabsorption coefficients and refraction indices of the samples. We havealso measured the optical limiting and Diffraction patterns of Zinc
nanostructured thin samples.

8564-63, Poster Session

Optimized biomimetic antireflection
nanostructure for photovoltaic applications
Fei Tao, Jiacheng Chen, Hang Zhou, Peking Univ. Shenzhen
Graduate School (China)
Minimizing surface reflection loss is critical when designing highefficiency solar cells. In recent years, biomimetic antireflection
nanostructures (such as ‘moth-eye’ structures), with their extraordinary
broadband and omnidirectional antireflection properties, have caught
much attention. It has been reported that single side biomimetic
nanostructures improved broadband transmission through ITO/glass.

However, reflection from the interface between active region and ITO/
glass still remains. In this study, we developed a double-side gradientindex nanostructure, and then examined its reflection spectrum withcomparison to different biomimetic nanostructures using a FDTD
simulation and effective medium theory. According to our study, any
abrupt interface will introduce significant reflection. In order to minimize
surface reflection, every abrupt interface should be replaced bygradient-index biomimetic nanostructures, including air/glass interface
and active/glass interface. Monolayer of silica spheres serves as
double-side gradient-index nanostructures, partially immersed into bothsides of glass/ITO/PMMA. Spheres with diameter smaller than lightwavelength show excellent antireflection properties. From simulation
results, in normal incidence, average reflection rate of double-side AR
coating (200nm sphere) is more than 4 times lower than single side AR
coating within visible spectrum region (350nm - 850nm). Besides, thismethod can be widely used because sphere shape is not necessary
in this antireflection structure; pyramid and parabolic shape are also
applicable to form the AR coatings. Details of how to apply suchbiomimetic nanostructures in thin film solar cells were also discussed.

8564-64, Poster Session

The role of localized surface plasmon in theTHz transmission of metallic rectangularhole arrays
Wei Xiong, Institute of Optics and Electronics (China) and Univ.
of Electronic Science and Technology of China (China) andGraduate Univ. of the Chinese Academy of Sciences (China);
Jun Yao, Institute of Optics and Electronics (China); Wei Li, Univ.
of Electronic Science and Technology of China (China); Jingling
Shen, Capital Normal Univ. (China)
We investigate the mechanism of transmission enhancement andthe suppression in rectangular aperture arrays at terahertz band. The
experimental results and numerical simulations suggest that SPPs
propagating along the Al-Si interface lie at the heart of the observed
phenomena. We also develop a simple model that explains the
behavior of surface waves excitation, propagating and interfering in
the array. In this interference model, we suggest there are three partsof radiation involved in the transmission phenomena. (1)First, the hole
excites part of the incident radiation into surface wave act as a sourceof surface wave. Second, parts of the surface wave excited by theholes propagate along the surface of the array and convert to surface
wave into free-space radiation. An instinct phase shift between twopath of SPPS, which is the key factor in our model, is suggested top. This interference model gives the direct evidence for role of SPPs
in the enhanced optical transmission. This study contributed a better
understanding of fundamental physics behind the extraordinarytransmission of aperture arrays at THz range and provided a simple
method for the THz devices designing.

8564-65, Poster Session

The synthesis of rutile nano-structured TiO2
composite under low temperature
Lei Zhang, Shijiazhuang Univ. of Economics (China)
As an important inorganic functional material, nanometer-sized TiO2
has many ynique physical and chemical properties. Titania is one of themost effective photocatalyst and widely applied in purification of air andwater because of its unique properties.
In order to improve the photocatalytic application of TiO2, the lowdensity material such as Pst and beas TiCl4 is proposed to be theraw carrier, and the nana-structured TiO2 composite is obtained by
combining the sol-gel technology and layer-by-layer self-assembly
methods; The pure rutile nano-structured TiO2 whose diameter is about
0.25mm are prepared under different conditions at low temperature. By

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Conference 8564:
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being calcined under 450°C the hollow sphere TiO2 is prepared and its
photocatalytic effect is studied.

8564-66, Poster Session

Simulation and analysis of the transparent
and super-hydrophobic micro-nano surface
structures
Zhijian Cai, Jianhong Wu, Soochow Univ. (China)
Super-hydrophobicity or “lotus effect” is an attracting feature forsurface scientists, for its great potential in anti-fogging, self-cleaningand drag reduction applications. In optical engineering, the surfaces
with the characteristics of super-hydrophobicity are also desired bymany optical elements in field operation, such as camera lens andvehicle window. Since the micro-nano structure has critical significancefor this feature, it’s reasonable to design such a functional surface inmicron and nanometer scale. However, most optical surfaces also
require high transparency to keep the light transmission and imaging
ability, which is a contradictive requirement on surface roughness,
i.e. hydrophobicity needs rough surfaces but transparency demands
smooth ones. It’s a big challenge to design a surface with bothfeatures of super-hydrophobicity and transparency. This paper used
Cassie wettability model to analyze the hydrophobicity on the onedimensional and two-dimensional periodical structures, and used thefinite-difference time domain (FDTD) method to analyze the opticalscattering and diffraction properties of the surface. With the simulation
and analysis, the design criteria of the transparent super-hydrophobic
surface were proposed, and the self-cleaning and imaging ability ofsuch surface were predicted.

8564-67, Poster Session

Absorption spectrum of the PbS doped silica
fibers fabricated by ALD and MCVD
Tang Ye, Jianxiang Wen, Yanhua Dong, Tingyun Wang,
Shanghai Univ. (China)
Quantum dots (QDs) provide unique advantages in the design of novel
optoelectronic devices owing to the ability to tune their properties
as a function of size. In order to apply this size effect in fiber optic
transmission, varies methods on QDs fabrication have already beenstudied, while the problem remained is that how to activate these QDs
in structure like optic fibers.
In this paper, the technique of atomic layer deposition (ALD) isintroduced to fabricate PbS doped silica fibers, whose absorption
peaks are discovered to be blue shifted from 1230 nm to 920 nm when
the number of ALD deposition cycles are varied from 80 to 30 during
their preform fabrication. We explain this result by suggesting the PbS
doped in fibers are under the 3D quantum confinement, i.e., quantum
dots (QDs). Under such assumption, a first approximation of the PbS
QDs radius is made by the effective-mass method. According to thewavelength these absorption peaks take place, radius of the PbS QDs
inside the fibers are estimated to be decreased from 3.5 nm to 2.8
nm, which is reasonable to the deposition number we have used when
preforms are being made.
The method of fabricating PbS doped silica fibers by ALD and MCVD
can then be utilized to shift the peaks of fibers’ absorption spectrum,and therefore, to enable them being excited at the wavelength one
prefers.

8564-69, Poster Session

Focusing of cross-polarized light byplasmonic nanoantenna metasurfaces withphase discontinuities
Jing Lin, Wu Shibin, Institute of Optics and Electronics (??)
An ultrathin metasurface which is constructed with planar arraysof V-shaped nanoantennas is presented to realize the focusing ofcross-polarized light. Based on the particular resonance propertiesof the V-shaped antennas, we can design the amplitude, phase, andpolarization state of the scattered light, and then choose the proper
antennas to satisfy the desired optical phase discontinuities. Numericalsimulation of an illustrative metasurface is performed through finite
element method (FEM) and shows agreement with the predesign. In
addition, broadband light focusing is also discussed in this article.

8564-71, Poster Session

Dispersive wave generation in As2S3
slot waveguide with four zero-dispersion
wavelengths
Shaofei Wang, Xianglong Zeng, Jungao Hu, Qianwu Zhang,
Tingyun Wang, Shanghai Univ. (China)
Recently, nanophotonic slot waveguides, owing to their abilities ofconfining light in an embedded low index slot region with high electricfield distribution, have attracted great research interests. What’s more,dispersion can be freely tailored by using different materials or structural
sizes, which can enable a number of interesting optical applications.
As2S3 has larger nonlinear coefficients in IR wavelength region andstrong Raman effects, which benefit the broad supercontinuum and IR
generation.
Dispersive wave generation from the emitted solitons perturbed by highorder dispersion are promising to generate femtosecond pulses in IR
region and achieve the nonlinear wavelength conversion to blue-shift insupercontinuum generation in highly nonlinear microstructure fibers.
In this paper, we present the theoretical design of As2S3 slot waveguidethat exhibits four zero-dispersion wavelengths and obtain a flattened
and low dispersion curve from near-IR to mid-IR wavelength range forabout 1800 nm bandwidth. We study the influence of slot waveguideon the total dispersion by choosing the different waveguide dimensions
in the nanometer scale. By using a full-vector mode solver, COMSOL,
we obtain dispersion of the quasi-TM mode through calculating theeffective refractive index as a function of wavelength, thus four zerodispersion points are located at: 1641nm, 2154nm, 2572nm, 3287nm.
The mechanism of generating this kind of concave dispersion profile ismode transition induced by anti-crossing effect.
We also discuss the dispersive wave generation in As2S3 waveguidewith four zero-dispersion wavelengths. Through numerical simulations
under some practical conditions, we demonstrate that a amount ofdispersive wave emission occur in As2S3 waveguide and the propertiesof the generated dispersive wave is fairly agree with previous detailed
studies, which can be used such as frequency metrology, opticalcoherence tomography and microscopy.

8564-72, Poster Session

Absorption and microstructure
characteristics of the PbS-doped silica
optical fiber
Yana Shang, Long Li, Jianxiang Wen, Yanhua Dong, Tingyun
Wang, Shanghai Univ. (China)
The microstructures of PbS-doped silica optical fiber have been built

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and calculated by Gaussian-03 software. The electronic and opticalproperties of the local microstructures were investigated by using
density functional theory (DFT). In the PbS-doped silica optical fiber
material, the microstructures of PbS(SiO2)n (n=1-6) were proposed, andthen the initial structures were optimized by using density functional
theory at the B3LYP level, with LANL2DZ+d (Pb) and 6-31G basis sets.
After this, the stable ground state geometries for PbS(SiO2)n (n=16) was obtained. We found that PbS molecule tended to form ring
structures with SiO2 molecules, just like the ring structures existingin the silica. And the gaps between the highest occupied molecularorbital (HOMO) and lowest unoccupied molecular orbital (LUMO) werealso calculated for every stable microstructure, which were found to
be different from the energy gaps of PbS clusters; Then the absorption
characteristics were analyzed, and the excited states of the proposal
microstructures in PbS-doped optical fiber materials were calculated
by using Hartree-Fock, with the singles configuration interaction (CIS)
method, and with the LANL2DZ+d(Pb) and 6-31G basis sets. We
found the characteristics of the excited states changed significantly
as the geometries of the microstructures changed. The PbS-doped
silica optical fiber, which was fabricated by modified chemical vapor
deposition (MCVD) and atomic lay deposition (ALD) were measured.
Finally, the optical properties of the PbS-doped silica optical fiber
measured by the experiments were compared to the results of thetheoretical calculation to deduce the possibly existing microstructuresin PbS-doped silica optical fiber.

8564-73, Poster Session

Functionalized nano-graphene oxide forcancer targeted imaging and photothermal
therapy
Da Zhang, South China Normal Univ. (China)
Integrin avb3 is heaterodimeric transmembrane receptor, expressedin endothelial cells. It has been extensively investigated as imaging
and therapy targets, due to their key roles in angiogenesis, leukocytes
function and tumor development and easy accessibility as cell surface
receptors interacting with extracellular ligands. Herein we propose an
active targeting nanocarrier system based on nano-graphene oxide(NGO) for imaging and photothermal therapy (PTT). The functioned
nano-probe based on integrin avb3 monoclonal antibody labeled NGO
was developed for targeting imaging and killing cancer cells upon 633
nm laser irradiation. The results revealed that the nanoprobe had ahigh efficiency targeted to the integrin avb3-positive U87-MG cells,with minimal influence on avb3-negative MCF-7 cells, and secure an
excellent cell killing efficiency once activated with proper light irradiation
with negligible dark toxicity. The feasibility of the graphene oxide, apotential photothermal transduction nanoprobe, may serve as a novel
probe for potential cancer targeted imaging and therapy.

8564-74, Poster Session

Photon correlation spectroscopy study of
mixture PEG with the AOT microemulsion
Soheil Sharifi, Univ. of Sistan and Baluchestan (Iran, Islamic
Republic of)
The correlation function as a function of delay time was study byusing photon correlation spectroscopy. The correlation function
as a function of delay time shows a single strength exponential for
AOT microemulsion with and without PEG. With increase of PEG
concentration the delay time is increasing and also shape of correlation
function is changing that describe the polydispersity increase
with increase of concentration of PEG. In this work, the collective
diffusion coefficient is constructing from the correlation function as afunction of delay time for the AOT microemulsion mixed with different
concentration of PEG. Our results shows increase of PEG concentration
slowing down the dynamic of systems.

8564-75, Poster Session

Pauli equation for semiconductor
quantum dots photoluminescence kinetics
investigation
Vadim Turkov, Mikhail Leonov, National Research Univ. ofInformation Technologies, Mechanics and Optics (RussianFederation); Ivan D. Rukhlenko, Monash Univ. (Australia);
Anatoly V. Fedorov, National Research Univ. of Information
Technologies, Mechanics and Optics (Russian Federation)
Optical methods are the most universal techniques for the investigationof semiconductor quantum dots, which allow the determination of
the dominant channels of energy and phase relaxation. We employ
the kinetic Pauli equation to develop the first generalized modelof the pulse-induced photoluminescence from the lowest-energy
eigenstates of a semiconductor quantum dot. Without specifying theshape of the excitation pulse and by the assuming that the energy andphase relaxation in the quantum dot may be characterized by a set ofphenomenological rates, we derive an expressions for the observable
photoluminescence cross section, valid for an arbitrary number ofthe quantum dot’s states decaying with the emission of secondary
photons. Our treatment allows for thermal transitions occurringwith both decrease and increase in energy between all the relevant
eigenstates at room or higher temperature. We illustrate the applicationof the developed model by considering the processes of resonant
luminescence and thermalized luminescence from the quantum dot
with two radiating eigenstates, and by assuming that the secondary
emission is excited with either a Gaussian or exponential pulse. Analytic
expressions describing the signals of secondary emission are analyzed,
in order to elucidate experimental situations in which the relaxation
constants may be reliably extracted from the photoluminescence
spectra.

8564-76, Poster Session

Anomalous size-dependent luminescencedecay from PbS quantum dots
Alexander Litvin, Peter Parfenov, Elena Ushakova, Alexander
V. Baranov, Anatoly V. Fedorov, Sergey A. Cherevkov, National
Research Univ. of Information Technologies, Mechanics andOptics (Russian Federation)
The study is devoted to investigation of size dependence of kinetic
and spectral luminescence properties of PbS quantum dots (QDs)in the near-infrared spectral region. Luminescence and absorbance
spectra of PbS QDs solutions in the range of 0.8—2 µm are recorded.
Radiative lifetimes are measured in the spectral range of 0.8—1.7 µm.
Lifetimes lie between 250 ns for the largest QDs and 2.5 µs for thesmallest. Lifetimes are close to predicted and Stoke shift is negligible
for large QDs. At the same time small dots demonstrate an unusual
long lifetimes and Stoke shift reaches 200 meV. These results confirm
a presence of the long-live below-gap state. The energy of this stateis size-dependent as well as radiative lifetime. Modeling showed that
relaxation from this state is dominant for small QDs and is negligible forlarge dots. This result is in a good agreement with experimental data.
Close-packed systems of PbS QDs demonstrate shorter lifetimes andsimilar size dependence. Red-shift indicates the presence of efficientenergy transfer process in the close-packed system.

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8564-77, Poster Session

Coherent random fiber lasers in weakly
scattering system based on waveguideeffectZhijia Hu, Qijin Zhang, Univ. of Science and Technology ofChina (China); Bo Miao, University of Science and Technology
of China (China)
Coherent random fiber laser is obtained by end pumping a hollow
optical fiber (HOF) filled with a dispersive solution of polyhedraloligomeric silsesquioxanes (POSS) nanoparticles and laser dye
pyrromethene 597 (PM597) in carbon disulfide (CS2). However,coherent random laser can not been observed for the same sample in
the quartz cuvette. We analyze coherent random fiber laser in weakly
scattering system by using sub-mean-free path regime. We suggestthat the coherent feedback is caused by the cooperative effect of lightscattering and waveguide effect. To research waveguide effect how
to trigger coherent fiber lasing actions, we vary the refractive index
of liquid core using the mixed solvent with different ratio of CS2 andethanol. Meanwhile, the influence of POSS nanoparticles with different
weight concentration to the fiber random laser has been researched.

8564-78, Poster Session

MHz isolated XUV attosecond pulses
generation using plasmonic enhancement inasymmetric metallic nanoantenna
Ying-Ying Yang, Institute of Semiconductors (China); Wei
Sun, Laboratory of solid state laser sources, Institute of
Semiconductors,Chinese academy of sciences (China); Qianguang Li, Hubei Univ. of Engineering (China); Ling Zhang, Huaijuan Yu, Xue-Chun Lin, Institute of Semiconductors (China)
The asymmetric cross antennas are proposed for the control of thepolarization and the selection of the mulit-wavelength via varying
the ratio of silver nanoattannas. It could generate the XUV pulse in
the incidence of arbitrary polarization angle after optimization. The
nanoplasmonic field enhancement in this silver cross antennas is fully
theoretically investigated for the generation of MHz isolated extreme
ultraviolet (XUV) attopulse. Numerical techniques are employed todetermine the plasmonic fields in coupled nanoantennas. Within fewcycle laser, optimal conditions of nanoantennas for the production of
MHz isolated attosecond pulse of XUV radiation via high harmonic
generation (HHG) have been identified and compared. It opens up the
possibility for the development of a compact source of XUV pulses
with MHz repetition rates and the next generation of the nanophotonic
devices.

the samples were measured in the wavelength range 400nm ~ 1000nm
at a modulating frequency of 175 Hz. The mechanism of SPV signals fordifferent structures was theoretically analyzed. Transitions between thesurface and bulk of electron-hole pairs (EHPs) generated by absorbed
photons were discussed. Which surface space charge region (SCR)
dominated contribution to SPV in a certain wavelength range wasdetermined. The SPV signals were calculated in a similar way as theopen circuit voltage of an illuminated photodiode. One-dimensional
continuity equations forwarded by Moss was adopted for determine the
distribution of excess minority carrier density. The parameters of thesamples were calculated with different methods. The ideality factor of
MIS configuration was investigated for samples with one side polishedin air ambient, which was determined by the dependence of the surface
photovoltage on incident photon intensity for band-to-band excitation.
Normal ‘linear SPV’ Goodman plot (inverse SPV vs. inverse absorption
coefficient) of GaAs substrate was applied for approach the minority
carrier diffusion length. The minority carrier drift current of different
layers were discussed in detail. At last the minority carrier diffusion
length of p-GaAs layer and p-AlxGa1-xAs layer, surface or interface
recombination velocity of different structure were calculated.

8564-80, Poster Session

Low loss optical modulator based on slotloaded waveguide for unmodified CMOS
process
Zhiping Zhou, Wei Tan, Qifeng Long, Huaxiang Yi, Feifei Hu,
Xingjun Wang, Peking Univ. (China)
How to fabricate silicon photonics devices and electronics devices
simultaneously in one shared CMOS process is becoming an urgent
issue needed to be solved. Recently, a platform of electronic-photonic
integrated circuits (EPICs) is proposed by MIT group, which makes
zero infrastructure changes to the existing state-of-the-art CMOS
process. However, in the platform of EPICs, polysilicon (poly-Si) layer
is a must layer to form modulator. That will result in very high device
loss, for example, 50~55 dB/cm for poly-Si waveguide because of highabsorption coefficient of poly-Si at optical communication wavelengths.
In this paper, we proposed and demonstrated numerically a novel
design of low loss depletion mode modulator based on poly-on-siliconslot-loaded waveguide for unmodified CMOS process. Different fromthe original design based on poly-on-silicon rib-loaded waveguide in
the EPICs platform, slot structure is introduced into the poly-Si region.
Taking advantage of confining light in low index region of slot structure,
loss induced by poly-Si is significantly reduced. The simulation results
show that after introducing slot structure into the poly-rib waveguide,
the total loss of modulator phase shifter is largely reduced from 54.2
dB/cm to only 22.9 dB/cm, including 7.1 dB/cm mode loss and 15.7
dB/cm doping loss when slot width is optimized to 250 nm. The design
is very simple and makes no change to the EPICs platform. And
performances can be expected to be further improved with optimizationof other parameters.

8564-79, Poster Session

Characteristics of p-GaAs/p-AlxGa1-xAs/
GaAs studied by surface photovoltage
Cui Fan, Nanjing Univ. of Science and Technology (China);
Gangcheng Jiao, Canglu Hu, Science and Technology on LowLight-Level Night Vision Lab. (China); Xinlong Chen, Yunsheng
Qian, Nanjing Univ. of Science and Technology (China)
A comparative study of semi-insulating GaAs substrate, p-AlxGa1-xAs/
GaAs and p-GaAs/p-AlxGa1-xAs/GaAs semiconductor heterojunctions
has been done using the surface photovoltage (SPV) spectroscopy
in metal–insulator–semiconductor (MIS) configuration. The epilayers
were grown by metal organic chemical vapor deposition on the
undoped GaAs substrate. The doping level was determined by cyclic
voltammetry (CV) measurement at room temperature. SPV spectrums of

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8564-81, Poster Session

Fabrication of two-dimensional metallic
photonic crystals using colloidal gold
nanoparticles
Zhaoguang Pang, Jing Yang, Hebei Normal Univ. (China)
We demonstrate the fabrication of two-dimensional (2-D) metallic
photonic crystals (MPCs) using colloidal gold nanoparticles, twodifferent fabrication methods that based on the laser interference
lithography and laser interference ablation are employed for theconstruction of gold nano-dot arrays in square lattice, respectively.
The microscopic and spectroscopic properties of the 2-D MPCs are
systematically characterized by the scanning electron microscope(SEM) and the angle-resolved optical extinction spectrum

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measurements, the strong couplings between the waveguide resonancemode and the particle plasmon resonance of the MPCs imply the
success of the fabrication methods, which show potential applicationsin optoelectronic devices and sensors.

8564-82, Poster Session

Influence of gold nanoparticle size on thetrapping performance of optical tweezers
Guang Lu, Harbin Engineering Univ. (China)
Gold nanoparticles are considered to be better probes than
the traditional polystyrene nanobeads in nanomaterials andnanobiotechnology. Meanwhile, optical tweezers are very popular
tool for manipulation and force measurement in these fields. Goldnanoparticles with different size will receive radiation forces withdifferent scale in optical tweezers. This paper theoretically studies thetrapping performance of the optical tweezers for the gold nanoparticle
with different size, and finally gives the relation curves between theradiation forces and the radius of the of the particle.

8564-83, Poster Session

Preparation of silver island films with tunablesurface plasmon resonance
Wanbing Lu, Wei Yu, Hebei Univ. (China); Xingkuo Li, Liping
Wu, College of Physics Science and Technology, Hebei
University (China); Xinzhan Wang, Hebei Normal Univ. (China);
Guangsheng Fu, College of Physics Science and Technology,
Hebei University (China)
Metallic island films exhibit light-induced localized surface plasmon
resonance, resulting in selective photon absorption and local
electromagnetic field enhancement. Many technological applications
using them have been developed such as surface-enhanced
spectroscopies, and chemical and biological sensors. In this paper,
silver island films are prepared by pulsed laser ablation in vacuum using
ns XeCl excimer laser. The effects of the number of ablation pulses, thetemperature and time of post-annealing on morphology and surface
plasmon resonance feature of the prepared silver island films areinvestigated by extinction spectra and scanning electron microscopy. It
is found that films deposited with a small number of ablation pulses (60or less), are not continuous, but formed of isolated nearly spherical Ag
nanoparticles. With increasing the number of pulses, the mean diameterand the areal density of the nanoparticles increase monotonically.
Further increase of the number of pulses, up to 240, quasi-percolated
Ag films are obtained, and for 600 pulses or more, continuous films will
be formed. Extinction spectra results show localized surface plasmon(LSP) is supported by the silver island films, while propagating surface
plasmon (PSP) was supported by the continuous silver films. The
LSP of silver island films consists of in-plane and out-of-plane LSP
resonance modes. By changing the laser pulse numbers and annealing
conditions, the longitudinal and transverse dimensions of silver islands
could be adjusted, and then the peak positions and peak widths ofin-plane and out-of-plane LSP resonance modes could be effectively
controlled.

8564-31, Session 7

High-sensitivity silicon photonic biosensors
based on cascaded resonators (Invited Paper)
Jian-Jun He, Zhejiang Univ. (China)
Silicon photonic biosensors based on cascaded resonators employing
the Vernier effect are shown to be capable of greatly increasing thesensitivity. Two implementation schemes are presented, one using

two cascaded ring resonators, and the other by cascading a FabryPerot laser with a silicon ring resonator. Simple intensity interrogation
schemes are developed to advance the planar waveguide sensor
technology towards low-cost practical applications. Silicon photonic
biosensors have great potential for lab-on-a-chip biological analysis.
Waveguide sensors based on single microcavity have been extensively
investigated. The commonly used sensing scheme is based on
wavelength interrogation. An external tunable laser or high-resolution
spectrometer is required to measure wavelength shift. The bulky
and cumbersome instrumentation offsets the advantage of miniature
waveguide devices and increases the overall system cost. A highly
sensitive architecture based on two cascaded microring resonators
employing Vernier effect was recently proposed and experimentallydemonstrated. It can also be operated in intensity interrogation modeusing a low-cost broadband source. Due to the Vernier effect, asmall variation of the refractive index of an analyte results in a large
wavelength shift in the envelope function of the transmission spectrumof the sensor, and consequently a large change in the transmitted
power. The refractive index change of the analyte can therefore bederived from simple relative intensity measurement between the output
port and the reference port without requiring any spectral measurement.
A high sensitivity of 450dB/RIU was achieved experimentally using
TE polarization mode, with a Vernier magnification factor of 150. The
intensity-interrogated sensing scheme can also be implemented bycascading a Fabry-Perot (FP) laser with a SOI ring resonator. The
FP laser serves as the light source as well as the reference comb forthe sensing ring. Its sharp emission peaks with high spectral power
density results in a higher sensitivity. Preliminary experiments havedemonstrated a sensitivity more than twice that of the double-ring
sensor.

8564-32, Session 7

Multiple transmission windows in abilayered metamaterial based on twisted
asymmetrically split rings
Ran Liu, Bo Na, Jinhui Shi, Zhengping Wang, Harbin
Engineering Univ. (China)
We theoretically investigate electromagnetic resonances of a bilayered
metamaterial in the optical frequency range. The metamaterial consistsof two stacked split ring resonators with a twist angle spatiallyseparated by a dielectric layer. The results show that multiple narrowband transmission peaks may be achieved by coupling mutually
between two twisted asymmetrical split rings at normal incidence, andmanifested transmission properties can be controlled efficiently by
regulating geometrical parameters of a unit cell. Our investigation offers
an effective way to manipulate the resonant behavior in metamaterials.

8564-33, Session 7

Fano resonance in whispering gallery
photonic microcavities (Invited Paper)
Yun-Feng Xiao, Bei-Bei Li, Xue-Feng Jiang, Yan Li, Qihuang
Gong, Peking Univ. (China)
Whispering gallery photonic microresonators with high Q factors
and small mode volumes open a myriad of lab-on-chip applications
ranging from fundamental physics to various photonic applications.
Here we experimentally reported Fano resonance in a single toroidal
microresonator, in which two whispering-gallery modes were excited
simultaneously through a fiber taper. By adjusting the fiber-cavity
coupling strength and the polarization of incident light, the Fano-likeresonance line shape could be engineered and further converted tothe electromagnetically induced transparency (EIT) like line shape. The
theoretical analysis revealed that both the Fano and EIT resonancesoriginated from an indirect-coupling of two originally orthogonal
WGMs, which was mediated by the common fiber taper waveguide.

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Furthermore, Fano resonances were observed in a coupled resonatorstructure in which a low-Q microdisk and a high-Q microtoroid
indirectly interact with each other mediated by a fiber taper. The Fano
resonance could be controlled to change periodically by adjusting the
distance between the two microresonators. The sharp Fano line shapeholds great potential in optical switching and sensitivity-enhanced
biochemical sensing.

8564-34, Session 7

Study of the spherical lenses as superlens
for subwavelength imaging
Qiming Dong, Chaoping Yao, Xiaowei Guo, Univ. of Electronic
Science and Technology of China (China)
The imaging resolution of a conventional optical microscope is limited
by diffraction to ~ 200 nm in the visible spectrum. Efforts to overcome
such limits have stimulated the development of optical nanoscopes
using metamaterial superlenses, nanoscale solid immersion lenses andmolecular fluorescence microscopy. These techniques either require
an illuminating laser beam or have limited imaging resolution above
100 nm. Recently, using optically transparent microspheres as far-field
superlenses to overcome the white-light diffraction limit was presented
by Wang etc. They experimentally demonstrated 50nm resolution with amagnification factor up to 8, which provides new opportunities to image
viruses and biomolecules in real time. Microspheres are placed on the
top of the object surface by self-assembly. Microsphere superlenses
collect the underlying near-field object information, magnify it (forming
virtual images which keep the same orientation as the objects in the farfield) and pick it up by a conventional objective lens.
For real use, however, it is necessary to know the influence on theimage quality when the parameters of the nanoscope vary, which isvery important to design the imaging setup. For an example, whatis the microsphere size allowed to obtain a good image for a fixednanostructure? In this paper, we numerically investigate the sphericallenses used for imaging nanoscale chrome gratings by using a FDTD
technique. The two-dimensional transverse magnetic wave at 400nm
is employed to carry out the calculation. The perfectly matched layer
absorbing boundary condition is used to efficiently terminate the outerboundary of the computational lattice. The simulations were done
as follows. A fixed microsphere size was firstly used for imaging ananoscale line. After obtaining the focusing nanojets, the refractive
index of microsphere was changed to see what the allowed object size
at a fixed microsphere is. Then, the microsphere size was change tounderstand what the allowed object size for good imaging is. Finally, atriangular array whose feature size well below the diffraction limit was
resolved by spherical lenses experimentally.
It is found that the focusing effect is efficiently enhanced with highrefractive index and large scale sphere. The internal electric-field peakshifts toward the shadow-side surface of the sphere along the forward
direction as the decrease of refractive index of sphere. It finally emerges
from the shadow-side surface of the sphere. As the diameter of spherelenses enlarges, the length of nanojet increases, in contrast, the full
width at half maximum waist decreases. The physics mechanisms
are presented to explain these phenomena. The waist width andlength of nanojets are compared respectively to evaluate the quality ofimage. At present the imaging experiment is in progress, the imaging
results will be given at subsequent paper. In conclusion, the near-field
focusing effect of spherical lenses is demonstrated theoretically andexperimentally and is believed capable of imaging objects with sizes
well below the diffraction limit at visible incident light.

8564-35, Session 7

A compact evanecently-coupled germanium
PIN waveguide photodetector
Zhijuan Tu, Kaibo Liu, Huaxiang Yi, Xingjun Wang, Zhiping
Zhou, Zhangyuan Chen, Peking Univ. (China)
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Germanium photodetectors have attracted much attention for theirefficient capability of absorbing near infrared light and its compatibility
with CMOS process. They are also the indispensable building blocks
in the monolithic silicon photonic integration. High bandwidth, low cost
Germanium waveguide photodetectors are urgently needed for highspeed monolithic integrated receivers in the optical communication
area. In this paper, we demonstrated a compact 1.6?10 ?m2
germanium pin waveguide photodetector on a Silicon-on-Insulator
substrate. Germanium with the thickness of 500nm was depositedby Ultra High Vacuum Chemical Vapor Deposition. Our germanium
photodetector exhibited a high 3-dB bandwidth of 20GHz at the
wavelength of 1.55?m. A clear open eye diagram at 10 Gb/s was also
obtained, although the pulse pattern generator can only provide a 10
Gb/s signal. In addition, the dark current of the photodetector wasmeasured to be 0.66?A at -1V bias voltage, which is much lower thanmost of the reported devices.
This work was supported by National High Technology Research andDevelopment Program of China (Grant No. 2011AA010302)

8564-36, Session 8

Simplified modal method of subwavelength
gratings (Invited Paper)
Changhe Zhou, Shanghai Institute of Optics and Fine
Mechanics (China)
A modal method is concerned with the modes excited, propagating,and coupled out into diffraction orders of a grating. Compared withthe well-known rigorous-coupled-wave algorithm (RCWA), the modal
method is less recognized. While the RCWA is a pure-numericalmethod, the modal method reveals a clear physical picture of themodes inside the grating. When a grating has a large period, it usually
has too-many modes that are excited and propagating, and its analysis
would be too complex. When a grating has a subwavelength period ora close-to-wavelength period, a few propagating modes will be excited.
When a few modes are concerned in the analysis, we have a simplified
modal method.
We have developed a simplified modal method to explain diffraction
due to a deep-etched fused silica grating. Here the “deep-etched”
means that the grating has a high ratio of deep-etched depth to thewidth of the groove. When a deep-etched fused silica grating has a
subwavelength period, there are a few (one to two) lower modes thatare propagating modes, and higher-order modes are evanescent.
We have developed an average effective-index concept to describea triangular deep-etched grating, and obtained simple analyticalequations to describe a three-port beam-splitting grating. These
analytical equations are impossible to obtain with the pure-numerical
RCWA. We have realized that this simplified modal method is a useful
tool for designing a variety of subwavelength deep-etched fused silica
gratings for many practical applications.

8564-37, Session 8

Grating imaging scanning lithography for
fabrication of large sized grating
Bin Yu, Changhe Zhou, Jia Wei, Shanghai Institute of Optics
and Fine Mechanics (China)
Diffraction grating is a high-resolution dispersion optical element. It
has been widely used as the key component in optical spectroscopy,
telecommunication multiplexing and laser systems, etc. Recently
there is a growing demand for large sized diffraction gratings inspectrometers industry, laser fusion facility, and its fabrication method
is also a hot topic now. To fabricate large sized gratings, we havedeveloped a grating imaging scanning lithography system. In thistechnology, the phase grating with jagged edge is used to generate
diffractive beams and the spatial filter is used to select ±1 orderdiffractive beams. Then two-beam interference on the substrate forms

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the grating fringes. At the same time, a 4f-system is used to form an
identical image with clear boundary in the interference area. A highprecision two-dimensional mobile station, which enables the accurate
positioning and move of the substrate, is utilized for complementary
cyclical scanning, thus the image stitching errors are effectively
eliminated. With this technology, we have fabricated a grating withperiod of 20µm and size of 100mm?100mm. In this paper the grating
imaging scanning lithography procedure is described step by step. The
principles and the experimental results are also explained in detail. With
the characteristics of a simple structure, high energy utilization andstability, this new lithography technology should be an efficient way tofabricate large sized grating in the future.

8564-38, Session 8

SOI-based bandwidth-tunable grating filter
with a large tuning range
Danhua Wu, Huaxiang Yi, Li Yu, Zhiping Zhou, Peking Univ.
(China)Guided-mode resonance grating filters (GMRGFs) have been of greatinterest recently. Normally a GMRGF can only function as a narrow or
a broadband filter, then property of tunable bandwidth has attracted
more and more attentions since several applications require resonant
filters with a tunable bandwidth.While a GMRGF with narrow bandwidth
can be used in DWDM system and laser devices, a GMRGF with awide bandwidth can be used in electro-optic modulators , light-matterinterfaces, lasers , and detectors. Realization of a resonant waveguidegrating filter with property of tunable bandwidth will be of greatsignificance in terms of applications.
An SOI-based bandwidth-tunable filter has been proposed andsuccessfully designed using binary blazed grating. The spectralreflectivity of this grating filter is investigated by Rigorous coupled-wave
analysis (RCWA) method. It is demonstrated that the bandwidth of thisgrating filter can be changed from 0.5nm to 90nm by adjusting theangle of incidence, which is a large tuning range.
When ? =45º, there is only one transmittance dip in the given
wavelength range for both polarization states, which corresponds to a
guided-mode resonance, proving that properties of narrow bandwidthis achieved; When ? is changed to 10º, there are two transmittance dipsat separate wavelengths for each polarization state, and the distance
between either pair is large enough, which makes the bandwidth of
this filter become broader. As a matter of fact, when we adjust theangle of incidence, the position where the guided-mode resonanceoccurs will change correspondingly and this will result in the changeof the bandwidth. We can take advantage of this property to design abandwidth-tunable grating filter. Like using thermal tuning in mocroring
resonator, angle of incidence is regarded as a controllable external
factor which could be easily used to change the reflection propertyof resonant filters. This characteristic makes this device have a large
number of potential applications in the laser devices and opticalcommunication systems.

8564-39, Session 8

Modal analysis of a fused-silica three-portbeam splitter grating
Wenting Sun, Changhe Zhou, Bin Yu, Shanghai Institute of
Optics and Fine Mechanics (China)
A new modal analysis based on the simple mode method and multibeam interference theory is proposed. Multiple reflection of propagating
modes at grating interfaces is considered by introducing equivalent
Fresnel coefficients into the diffraction process analysis. Then the
proposed modal analysis is applied to design a rectangular-groove
fused-silica grating as a three-port beam splitter. The diffraction
efficiency expressions are derived in this paper, which are analogous
to the results of multi-beam interference of a plane-parallel plate.

Dependence of diffraction efficiencies of the transmission 0th and 1st
diffractive orders on the groove depth is obtained with optimized grating
period and duty cycle. Compared with the simple mode method, theresults based on the proposed modal analysis can match much betterwith those of rigorous coupled-wave analysis (RCWA), which proves
the validity of the new modal analysis method. Moreover, the analysis
results give an intuitionistic proof that the ideal 100% diffraction
efficiencies of the transmission diffractive orders can’t be realized andthe transmission 0th order can’t be cancelled in low-contrast grating. As
the effective refractive indices of diffractive orders are introduced into
the diffraction process analysis, this modal analysis is all valid under
the usual incidence cases of normal incidence, Littrow mounting, andsecond Bragg angle incidence. More importantly, the proposed modal
analysis provides a more accurate physical image of grating diffraction
process, which should be a useful analysis tool for high-density grating.

8564-40, Session 8

Dual structure waveguide grating triplexer
based on silicon-on-insulator
Junbo Yang, Xu Suzhi , Xu Jia , Kuo Zhou , National Univ. of
Defense Technology (China)
A compact dual-structure waveguide triplexer which consists of two
waveguide gratings with different period and fill factor is presented.
It not only achieves efficient coupling between single mode fiber anda silicon-on-insulator optical waveguide, but also realizes effectively
splitting, especially, for three different wavelengths, i.e. 1.31µm, 1.49µm
and 1.55µm. By appropriate choice of waveguide/grating parameters
including thicknesses, periods, height, and fill factor, to optimize themode matching, and improve coupling efficiency and decrease thevalue of crosstalk, the coupling efficiency for 1.55µm wavelength canreach about 70% for TE polarization light over the 40 nm wavelength
bandwidth. The crosstalk is about -12dB. Simultaneously, for 1.31µm
and 1.49µm, the coupling efficiency is 58% and 40%, respectively.
Moreover, the crosstalk of the left and the right branch of waveguide is-10dB and -14dB, respectively.

8564-41, Session 8

Ultra-short silicon MMI duplexer
Huaxiang Yi, Yawen Huang, Xingjun Wang, Zhiping Zhou,
Peking Univ. (China)
The fiber-to-the-home (FTTH) systems are growing fast thesedays, where two different wavelengths are used for upstream anddownstream traffic, typically 1310nm and 1490nm. The duplexers are
the key elements to separate these wavelengths into different path incentral offices (CO) and optical network unit (ONU) in passive optical
network (PON). Because MMI have the multimode structure, it has
some benefits including large fabrication tolerance, low-temperaturedependence, and low-polarization dependence. However, conventional
MMI duplexer is too large to integrated. Here we present a novel silicon
duplexer based on cascaded MMI.
Based on the self-image mechanism, the input light can obtain auniform image through n? self-image-length in the MMI, where n is
integer. In such a cascaded MMI duplexer, we made n=1 at MMI1,
where 1490nm light formed the image at the cross-port. With 1310nm
light input, there is no image at the cross-port, because the self-imagelength for 1310nm is longer than the one for 1490nm. The MMI2 wasplaced after the MMI1 to collect the propagation mode for 1310nm.
Then the self-image for 1310nm was obtained at the bar-port when n=1
also.
The experiment was carried on with the SOI wafer of 340nm top silicon.
The spectral of the duplexer was obtained only around 1490nm. The
extinct ratio is measured larger than 10dB. Another single wavelength
laser was used to provide 1310nm. The extinct ratio for 1310nm is
about 13dB.

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Conference 8564:
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8564-42, Session 98564-45, Session 9

On-chip polarization handling for silicon
nanophotonic integrated circuits (Invited
Paper)

Plasmon spectroscopy and imaging ofindividual gold nanodecahedra: a combined
optical microscopy, cathodoluminescence,and electron energy-loss spectroscopy
study

Daoxin Dai, Zhejiang Univ. (China)
Silicon-on-insulator (SOI) nanowire provides a very promising way torealize the future large scale nano-photonic integrated circuits becauseof the CMOS compatibility and the ability for ultrasharp bending.
However, SOI nano-PICs usually suffer the issue of severe polarizationdependence due to the giant birefringence. A general solution is using
the so-called polarization-diversity technology, which is based onpolarization handling with the devices like polarizer, polarization-beam
splitter, as well as polarization rotator. On the other hand, polarization
handling technologies are also very important for coherent opticalcommunications. In this paper, we give a review for our recent workon silicon polarizers, PBS, as well as polarization rotators. First,
small silicon polarizer is presented by utilizing the mode hybridization
effect in a straight shallowly-etch SOI ridge waveguide. Second, an
asymmetrical evanescent coupling system is presented as a better
option than a symmetrical coupling system when used for realizing
small PBSs because of the larger bandwidth, smaller foot-print andlarger fabrication tolerance. Three types of ultrasmall PBSs based on
silicon-on-insulator (SOI) nanowires are proposed and their design rules
are given. Thirdly, a novel concept for an ultracompact polarization
splitter-rotator is proposed by utilizing mode evolution and mode
coupling. An adiabatic taper is introduced to realize the mode evolution
from the TM fundamental mode to the first-order TE (TE1) mode, whichis then converted to the TE fundament mode of an adjacent narrow
waveguide through the asymmetrical coupling.

8564-43, Session 9

High-speed optical logic functions using Sinanocrystal slot waveguides
Jian Wang, Huazhong Univ. of Science and Technology (China)
Optical digital signal processing may be required to overcome thespeed limitation of electronics and support necessary functions for
future computation and communication fields. Optical nonlinearities are
candidates to enable various digital signal processing functions, among
which logic gates are building blocks. Besides basic logic operations(AND/OR/NOT/XOR/NOR/NAND/XNOR), advanced logic functions havealso gained great interest, such as data selector, Fredkin gate, halfadder, half-subtracter, full-adder and full-subtracter.
Driven by the increasing trend of large-scale integration, it is desirable
to achieve logic functions using compact devices. Si-waveguide has
attracted increased attention owing to its compactness and CMOScompatibility. In this scenario, a laudable goal would be to realize
advanced logic functions using optical nonlinearities in Si waveguides.
In this paper, we review our recent works on high-speed advanced
logic functions by exploiting optical nonlinearities in Si-nanocrystal(Si-nc) slot waveguides. We present Si-nc slot waveguides with thelight guided in the low-refractive-index Si-nc slot region sandwiched byhigh-refractive-index Si regions. The Si-nc slot waveguides show tightlight confinement and enhanced nonlinearity. Based on twin degenerate
four-wave mixing (FWM) processes, we demonstrate all-optical
160-Gbit/s simultaneous half-adder and half-subtracter using a single
Si-nc slot waveguide as well as all-optical 160-Gbit/s data selector
and Fredkin gate using two Si-nc slot waveguides. Moreover, based on
twin degenerate FWM processes and cross-phase modulation (XPM)
induced nonlinear polarization rotation, we demonstrate all-optical
160-Gbit/s simultaneous full-adder and full-subtracter using three Si-nc
slot waveguides. Eye diagrams, extinction ratio (ER), quality factor (Q)and eye opening are analyzed to assess the operation performance.

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Viktor Myroshnychenko, Consejo Superior de Investigaciones
Científicas (Spain); Jaysen Nelayah, Univ. Paris-Sud 11(France); Giorgio Adamo, Univ. of Southampton (United
Kingdom); Nicolas Geuquet, Facultes Univ. Notre Dame de la
Paix (Belgium); Jessica Rodríguez-Fernández, Isabel PastorizaSantos, Univ. de Vigo (Spain); Kevin F. MacDonald, Univ. ofSouthampton (United Kingdom); Luc Henrard, Facultes Univ.
Notre Dame de la Paix (Belgium); Luis M. Liz-Marzán, Univ. deVigo (Spain); Nikolay I. Zheludev, Univ. of Southampton (United
Kingdom); Mathieu Kociak, Univ. Paris-Sud 11 (France); F.
Javier García de Abajo, Consejo Superior de Investigaciones
Científicas (Spain)
The current tremendous interest in the optical properties of metal
nanoparticles is due to their ability to host localized surface
plasmon excitations in the visible and near-infrared parts of thespectrum. Plasmons can be tailored via the size and morphology
of metal nanoparticles. Knowledge and experimental access to theelectromagnetic field distributions associated to localized plasmon
excitations in metal nanoparticles, with high degree of energy andspatial resolution, are of critical importance in the development ofapplications such as single-molecule detection, and surface-enhanced
Raman scattering.
Here, we demonstrate the combined use of optical dark-fieldmicroscopy (DFM), cathodoluminescence (CL), and electron energy-loss
spectroscopy (EELS) to study localized surface plasmons on individual
gold nanodecahedra. These techniques provide information aboutplasmon excitations by recording different physical processes: lightscattering exerted by the particles on externally incoming light, radiation
emission produced by interaction with an electron beam, and energy
loss suffered by those electrons. By exciting surface plasmons witheither external light or an electron beam, we experimentally resolve a
prominent dipole-active plasmon band in the far-field radiation acquired
via DFM and CL, whereas EELS reveals an additional plasmon mode
associated with a weak dipole moment. We present measured spectraand intensity maps of plasmon modes in individual nanodecahedra
in excellent agreement with boundary-element method simulations.
Our comparative assessment of the experimental techniques usedin this work demonstrates an extremely high capability of electronenergy-loss spectroscopy in resolving and imaging surface plasmons insubwavelength metal nanoparticles with unrivalled spatial and energy
resolution.

8564-46, Session 9

Impact of emission broadening on plasmonicenhancement with metallic gratings
Xue Feng, Kaiyu Cui, Yidong Huang, Tsinghua Univ. (China)
In particular, the surface plasmon polariton (SPP) is attractive toenhance the spontaneous emission (SE) from active materials due tothe larger density of state (DOS) and smaller mode volume comparing
with optical wave, namely Purcell effect. Usually, the Purcell factor(PF) is calculated from the reduced form of Fermi’s golden rule,
where only the DOS and mode volume of photon (or SPP mode) are
involved. Obviously, the PFs calculated with reduced form exclude theinfluence of active material and only evaluate the effect of cavity or SPP
waveguide. However, for a practical emitter, the linewidth could notalways be ignored. For example, the ensemble emission linewidth of

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mass Si-NCs is about 220meV~400meV (90~160nm), which are muchwider than the linewidth of the SPP DOS
In this work, the PF of SPP mode on Au-Si3N4 grating is calculatedwith full integration formula of Fermi’s golden rule by taking accountof the spontaneous emission linewidth from single silicon nanocrystal(Si-NC). The calculated PF is about 1.7~1.4 within the emission rangeof 1.9~1.6eV. Comparing with the PF value of 266.9~30.1, which is
calculated without including the emission linewidth of Si-NC, it could
be easily concluded that the impact of rather wide emission linewidthis fatal for applying plasmonic enhancement. To obtain some useful
guidelines, we also discuss the necessary linewidth for effective
plasmonic enhancement on Si-NCs. It is found that if the emission
linewidth could be decreased to several tens of micro-eV, plasmonicenhancement would be helpful.

waveguide (THPW) and traditional dielectric waveguide (TDW), arediscussed with finite-difference time-domain method (FDTD). With asmall radius R=0.8µm, the bends of TDW has significantly larger loss
compared to the other three due to its prodigious losses by radiation.
What’s more, when the radius of the bends decreases, loss of bends
based on HPWMOSB increases slowly due to metal absorption
loss, while that of the HPWMISB and THPW presents a rapid growth
attributed to largely increased radiation loss.
Finally, a racetrack resonator based on HPWMOSB is designed withan outer radius of 0.8µm and straight waveguide of 0.89µm, which
presents an extinction ration of 15.14dB and an insertion loss of
0.98dB. An ultracompact racetrack resonator with an outer radius of
0.5µm and straight waveguide of 0.1µm is also presented, which has a
low transmission loss of 0.25dB and a high extinction ratio of 12.55dB.

8564-47, Session 98564-49, Session 10

Eigenvalue analysis of plasmonic
waveguides in layered geometries

Super-resolution imaging and moleculesensing by plasmonic nanoparticles on AgOx
thin film (Invited Paper)

Aytac Alparslan, Christian Hafner, ETH Zurich (Switzerland)
Due to the improvements in nanometer scale fabrication techniques,various photonic devices became popular research subjects intheoretical and applied electromagnetics. The analysis of plasmonic(lossy and dispersive) waveguides is one of the subjects that attracts
much attention, since they are one of the main building blocks ofphotonic devices. Waveguides built in or on a multilayered geometry
may exhibit extraordinary properties that cannot be observed instandard waveguides or waveguides in free space, e.g. guided wave
modes in some layers, surface plasmon polaritons along metallic
layers etc. In the analysis of such waveguides, commercial simulation
tools exhibit difficulties finding the modes, especially when losses arepresent. In order to design such structures, a numerical method thatcan efficiently analyze the effect of layered geometries and losses inwaveguides is of huge importance.
The Multiple Multipole Program (MMP) is one of the most accurate
simulation tools for the analysis of plasmonic structures. It is aboundary discretization method that uses a set of analytical solutionsof the Maxwell’s equations (point sources, plane waves, Bessel
functions, etc., so called expansions) as an approximation of theelectromagnetic fields. In this work, the modified layered geometry
Green’s functions, i.e. the electromagnetic fields generated by a point
source in a layered geometry, are used as an expansion set in MMP.
Using these expansions in combination with a sophisticated eigenvalue
search, the complex propagation constants of the waveguide modes
are determined in an efficient way. In the talk, the derivation of the
new expansions and using them in MMP will be discussed. Several
numerical examples from OpenMaX, the open-source program that
includes the latest MMP version, will be shown and compared withother numerical methods in order to demonstrate the efficiency andadvantages of the method.

8564-48, Session 9

Ultracompact racetrack resonators based on
hybrid plasmonic waveguides
Liangxiao Tang, Feifei Hu, Zhiping Zhou, Peking Univ. (China)
We propose and analyze a new hybrid plasmonic waveguide composedof a low index layer in between a metal and a high index layer, which
can be used to realize a sharp bend with little radiation loss.
First, the effect of the geometrical parameters of the structure on thedevice is discussed with the help of simulation using finite element
method (FEM).
Secondly, bends based on four different kinds of waveguides,
hybrid plasmonic waveguide with metal lying outer side of the bend
(HPWMOSB), hybrid plasmonic waveguide with the metal layer lying
inner side of the bend (HPWMISB), traditional hybrid plasmonic

Din Ping Tsai, Ming Lun Tseng, National Taiwan Univ. (Taiwan);
Yu-Hsuan Lin, Instrument Technology Research Ctr. (Taiwan);
Chia Min Chang, Pin Chieh Wu, Yao-Wei Huang, You Zhe
Ho, Ding-Wei Huang, National Taiwan Univ. (Taiwan); HaiPang Chiang, National Taiwan Ocean Univ. (Taiwan); RuShi Liu, National Taiwan Univ. (Taiwan); Greg Sun, Univ. ofMassachusetts Boston (United States)
In this talk we report the results for the applications of silver oxide thinfilm (AgOx) on molecule sensing and super-resolution imaging. Under
light illumination, Ag nanoparticles can be generated on the AgOx thinfilm in situ. This photo-induced chemical reduction of AgOx thin film
is very useful for the plasmonic applications therefore. For the superresolution imaging, the focused-laser-generated silver nanoparticles in
the AgOx thin film act as a scattering centres for activating the nearfield optical imaging process. Localized surface plasmon generated at
photo-generated Ag nanoparticles can enhance the near-field opticalsignals and functions as a probe for recording and readouts. Using
this scheme, the 100-nm-dimeter polystyrene nanosphere can be
resolved by the focused laser beam with a wavelength of 635 nm. This
“near-field cover glass slip” can achieve high spatial resolution andsimilar near-field scanning microscope function with the advantages ofa higher scanning rate, less mechanical damage, low costs, and highcompatibility with conventional optical microscopy. On the other hand,under light illumination, the plasmonic “hotspot” can be formed at thelaser-generated Ag-nanoparticle aggregates, which can be used as
the plasmonic substrate for molecule imaging and surface-enhanced
Raman scattering measurement. The laser-processed AgOx thin films
exhibit broadband enhancement of optical absorption and effectivelyfunction as active SERS substrates. Probing of the plasmonic hotspots
with dyed polymer beads indicates that these hotspots are uniformly
distributed over the treated area. It holds promise as a highly efficientand cost effective approach for applications in imaging and molecularsensing.

8564-50, Session 10

Tunable nano-pattern generation based on
surface plasmon polaritons
Chinhua Wang, Fuyang Xu, Yiming Lou, Bing Cao, Soochow
Univ. (China)
We present a numerical observation of a tunable 1D and 2D nanopattern generation and photolithography technique based on a surface
plasmon resonant cavity formed by a metallic grating and a metallic
thin-film layer separated by a photoresist layer. The tuning capability
is implemented by varying the cavity length combined with the221A  
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Conference 8564:
Nanophotonics and Micro/Nano Optics
polarization of the incident light, from which different surface plasmon
interferometric patterns with inherently higher optical resolution thanthat of conventional surface plasmon techniques are generated in
the cavity of photoresist layer. The physical origin of the tunability is
analytically confirmed by the dispersion relation derived from the cavity
system as well as the interferometric behaviors of the surface plasmon
polaritons. The technique opens a new possibility to generate tunableultra-deep subwavelength patterns by using a fixed diffraction-limited
mask with capability of large area, deep exposure depth and flexibilityof arbitrary 2D patterns.

8564-51, Session 10

Subwavelength imaging of self-assembled
triangular nanoparticles through a silver
superlensQiming Dong, Chaoping Yao, Xiaowei Guo, Univ. of Electronic
Science and Technology of China (China)
Near field perfect imaging technique has received considerable
attentions since 2000 when Pendry predicted that a diffraction free
image can be produced through a flat slab lens on which SPs are
excited and allow propagating and evanescent waves to pass into
the recording medium when normal light source illuminates the silver
lens through the mask. A lot of numeric simulations and experiments
has been done to demonstrate the subwavelength imaging technique,which provides promises for high resolution nanolithography well below
diffraction limit.
In most of these early experiments, however, the masks used targeted
one dimension(1D) gratings with different periods. As we know, thegrating is a periodic object which sometimes results in a frequencydoubled image. It is necessary to investigate the imaging for nonperiodic objects. In this paper, subwavelenght imaging through a silver
superlens structure is performed by using self-assembled triangularparticle mask. The schematic of the experimental setup is shown in
Figure 1. The setup includes five layers, that is, mask/PMMA/silver/
PMMA/recording medium. The mask is made of triangular nanoparticles
on a quartz glass and PMMA as the dielectric spacers. The structure
size mainly refers to the previous work and we confirmed the silver
thickness is 35nm and the spacer thicknesses are 20nm and 15nm,
respectively.
The first step in the experiment is fabrication of chromium mask onto
a quartz glass substrate. Polystyrene spheres at 430 nm diameter areused for fabricating particle arrays mask by self-assemble method andthen deposit a 40 nm thick chrome layer on it. A triangular particle arrayis formed after removing the PS spheres with an ultrasonic bath for 30
second. The side length of the triangle nanoparticles is 120 nm, about
1/3 of the incidence wavelength. Then, a 20 nm PMMA layer is spincoated on the mask as the first dielectric spacer. A 35 nm silver layer isdeposited on the sample using magnetron sputtering, followed by spincoating of 15nm PMMA layer as the second dielectric spacer. The resist
is spun on a silicon substrate and brought into vacuum contact with thesecond PMMA layer. Exposure is performed by mounting the superlens
structures onto a rigid support that is compatible with a commercial
Karl Suss optical mask aligner with 365 nm wavelength.
The resulted image in the photoresist is obtained. Due to the loss ofmuch high frequency information, the particles’ tips are rounding. The
side length of the imaged triangular particles is about 50nm, whichis twice smaller than the original size and about 1/7 of the incidence
wavelength. But our experimental results demonstrated that thesuperlens wavelength imaging of nanoparticles. In future work, we will
focus on better control of the imaging quality.

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8564-52, Session 10

Ultra-deep subwavelength periodic
patterning through multilayered
metamaterial microcavity
Jigang Hu, Yongqiang Yu, Chunyan Wu, Linbao Luo, Hefei
Univ. of Technology (China); Xiangxian Wang, Hai Ming, Univ. of
Science and Technology of China (China)
In this work, we theoretically demonstrate an approach to achieve thesub-20 nm patterns feature sizes at the wavelength of 248 nm with
p-polarization, utilizing a designed plasmonic cavity formed by themetallo-dielectric multilayer stacks (MDMS) and a metal layer coatedsubstrate with a chromium mask on the top. This 1-D metamaterial
plasmonic cavity enables the periodic SPP interference patterns
with the high uniformity and intensity through the high pass filteringof the MDMS and SPP cavity resonance coupling. High resolution(~lambda/15) and visibility (~1) of patterns have been numericallydemonstrated at the cavity bottom, and the period of patterns is betterstabilized against the variation of the cavity length in comparison
with the conventional grating metal waveguide structure. This
proposed ultra-deep subwavelength patterning method offered by themetamaterial cavity system provides a promising route in obtaining thelarge-area nano-scale patterns with high uniformity and visibility.

8564-54, Session 10

Amplification of surface plasmon polaritons
in a methyl orange doped dielectric loaded
SPP waveguide
Feng Huang, Hai Ming Yuan, Xiudong Sun, Harbin Institute ofTechnology (China)
Surface plasmon polaritons (SPPs) have received a significant attention
in recent years because of their potential application in photonic
devices at the subwavelength scale. Many SPP waveguide designs
have been demonstrated, such as the long range SPP waveguide, thedielectric loaded SPP waveguide (DLSPPW), metal-insulator-metal
waveguide, etc. Being well bounded with small light spot and having
small bending loss, the DLSPPW has been widely used in waveguidering resonators and in-line Bragg grating, and exploited for wavelength
selection in the telecommunication rage. However, the intrinsic
propagation loss of DLSPP leads finite propagation length (~40um)
and limits its application. In this paper, we introduced methyl orange
doped polymer to DLSPPW used as gain medium to amplify the surface
plasmon polaritons propagating in this waveguide. The DLSPPW
also had gratings at its input and output ports to couple in and out
DLSPP. Upon the illumination of pump light, the DLSPP propagatingin this waveguide was amplified. In addition, we theoretically andexperimentally investigated the amplification characteristic. Bymeasuring the power intensity of the output light in different condition,
we got the gain factor as functions of the pump energy density, gain
medium length and methyl orange doping density. When the pumpenergy density was higher than a threshold value, the power intensityof the output light was amplified as compared with those achieved
without pump light, indicating that the loss of this waveguide was partly
eliminate by the gain.

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Nanophotonics and Micro/Nano Optics

8564-55, Session 10

High performance absorber structure using
subwavelength multi-branch dimers
Kebo He, Guangyao Su, Peking Univ. Shenzhen Graduate
School (China); Zhaoyu Zhang, Peking Univ. (China)
We proposed a type of sub-wevelengthmulti-branch dimers which
exhibit several tunable dipole-dipole-like plasmonic resonances.
Three resonances found in a three-branch dimer, and each statecorresponding to a unique current distribution on the dimer and thatunique current distribution is mostly along one of three branches. On
another word, these states.arecontrollablethrough the design of thegeometry which determines the oscillating path of the polarization
charges on each resonance state. So, the LSP resonant state can beeasily tuned in the dimer.
This unique property is extraordinarily useful to in the applicationof multi-resonances devices. An ultrathin absorber structure using
three-branch dimer was proposed too. As a comparison, bothabsorptionspectra of the absorber structure with three-brunch dimer
and that with square dimer of the same area were acculated. In thecalculated wavelength range, there is only one peak showing in the
structure with square dimer. However, in the structure with the threebranch dimer,three peaks exist, which certainly broad the absorption
range and increase the total absorption as well. The total absorptionof the three-branch dimer absorber is about two times of that of thesquare dimer absorber structure and further improvement can beachieved through the optimization of the structure.
Due to the tunable ability of the dimer, this absorber structure offer anpath to fulfill broadband and wavelength tunablewithin optical frequency
device, which could find its application in broadband thin-film thermal
emitters, thermophotovoltaic cells, and multi-color filters.

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