bluuebunny/crossref_metadata_2025 huggingface dataset:
Surface-Emitting Laser Diode Arrays (Lase-Arrays™) - Multi-Channel Applications in Optical Storage
Authors: Jewell J.L. , Fu W.S. , Bryan R.P. , Swirhun S.E. , Quinn W.E. , Olbright G.R.
Published: February 2023

Consumers of optical storage products strongly desire optical disk and tape drives with high data transfer rate for many applications including: multimedia, archival storage, software distribution and reconnaissance. In order to increase the data rate at which information is read from or written to optical storage media, parallel multi-channel systems have been proposed or demonstrated [1,2]. Our approach aims to increase data transfer rates by more than an order of magnitude through multi-channel drives having minimal effect on the hardware and on the cost of the product. The emergence of vertical-cavity surface-emitting laser arrays (Lase-Arrays™), [3,4] enables unique multi-channel configurations for high-data-rate parallel optical reading and writing of information. Lase-Arrays represent a new class of semiconductor laser diodes which, unlike conventional edge-emitting semiconductor laser diodes, are directly "printed" in ID and 2D arrays using standard III-V compound semiconductor circuit fabrication techniques. Fig. la shows a photograph of a portion of a 2x32 Lase-Array. Lase-Arrays emit light perpendicular to the plane of the wafer, as compared to edge-emitting laser diodes which emit light in the plane of the wafer. Also, unlike edge-emitters, Lase-Arrays have circularly-symmetric, aberration-free beams. Arrays of microlenses are straightforwardly integrated to Lase-Arrays (Fig. la) to enable optical mappings which are impossible with conventional macroscopic optics, for example, mapping an array of widely-spaced, low-fill-factor lasers to an array of closely-spaced, densely-packed spots. This mapping is ideal for multi-channel optical storage applications using either disks or tape as the storage medium.
A Development of Non-Compressed NTSC Digital Video Disk Recorder (1)
Authors: Sekiguchi T. , Miyatake M. , Uchikawa T. , Matui T. , Inada H. , Ono Y. , Araki S.
Published: February 2023

The video disk recorder has been developed that can record non compressed NTSC digital video signal for 32 minutes on ϕ30cm both side magneto-optical disk.
High Track Density Recording on Phase-change Optical Disks Using Land and Groove Method
Authors: Nishiuchi Kenichi , Ohno Eiji , Miyagawa Naoyasu , Ide Kazuhisa , Sakaue Yoshitaka , Akahira Nobuo
Published: February 2023

Phase-change optical disks showed available cross talk characteristics even the signals are recorded on tracks with 0.8 μ m pitch using land and groove recording method.(1) In this paper, the results of a feasibility study of high track density recording for rewritable disk system are reported. The influence of adjacent tracks overwriting upon cross talk and jitter were measured for various track pitches using a 680nm laser diode and optics of NA 0.6.
Ultra High Density Recording Using a Solid Immersion Lens
Authors: Kino G. S.
Published: February 2023

The spot size of an optical storage system is determined by diffraction to be approximately λ/2 N.A., where λ is the free space wavelength, and N.A. is the numerical aperture of the objective lens. For λ = 0.89 μm and N.A. = 0.55, the spot size is approximately 0.8 μm. To improve the definition, it is necessary to work at shorter wavelengths, typically in the blue, which yields a definition of about 0.4 μm, and/or to increase the numerical aperture. A further possibility is to employ near field optics in the manner described by Betzig.1 He uses a tapered fiber covered with a metal film with a small pinhole at the end. The definition of the system is determined by the size of the pinhole, and can be 50 nm or less. The advantages of the system are its excellent definition and it polarization-preserving capability for magneto-optic storage. The disadvantages of the system are its poor light efficiency and the fact that it can only observe a single spot at a time, thus limiting its tracking ability.
Optical Disk Jukebox Performance in Multi-User Applications
Authors: Hauser Susan E. , Roy Gautam , Thoma George R.
Published: February 2023

The Lister Hill National Center for Biomedical Communications, a research and development division of the National Library of Medicine, is evaluating an optical disk jukebox as a digital image store to support prototype systems for image distribution over the Internet. This paper summarizes a study undertaken to determine the performance characteristics of the jukebox to support multiple image databases simultaneously accessed by multiple users. A motivation for this investigation is the need to provide users access to digitized images of medical documents and radiographs.
The Feasibility of a CD-compatible Erasable Disc
Authors: Coombs J.H. , Jongenelis A.P.J.M. , van Es W. , Jacobs B.A.J. , Holtslag A.H.M.
Published: February 2023

An erasable Compact Disc is a disc that, after the recording process is complete, satisfies the specifications for a Compact Disc [1]: only if it does so can it be considered truly ‘backward compatible’. The standard contains two key specifications for the signal written into the disc: the reflectivity of unwritten regions must be over 70%, and the signal modulation as measured by a Compact Disc player must be 60% or over. The writing process, although not specified for backward compatibility, should allow normal CD data rates, most simply through Direct Overwrite (DOW) at a linear velocity of 1.2-1.4 m/s.
Sn-Sb-Se Phase-Change Media for High-Density Write-Once Optical Disk
Authors: Nishida Tetsuya , Sugiyama Hisataka , Horigome Shinkichi
Published: February 2023

Write-once optical disks storing digital data have been on the market for a decade.1),2) Increasing data capacity has been strongly required for the next generation. To meet this demand, a new phase-change optical disk with Sn-Sb-Se recording film and Sb-Bi reflective film on a polycarbonate substrate was developed. In this paper, we report fundamental characteristics of these films and write/read experiments of the disk using a 690-nm-wavelength diode laser.
High Density Mark Edge Recoding on a Phase Change Rewritable Disk by a 680nm Laser Diode
Authors: Ishida Takashi , Shoji Mamoru , Miyabata Yoshiyuki , Shibata Yasumasa , Ohno Eiji , Ohara Shunji
Published: February 2023

Mark edge recording is one of the approaches to realize larger data capacity. High density mark edge recording conditions on a (Ge-Sb-Te) phase change rewritable disk using a 680nm laser diode, NA 0.6 head are reported here.
High Density Recording Providing over 1 GB Capacity for a 90 mm Phase Change Optical Disk
Authors: Kobori Hiromichi , Hasegawa Hiroshi , Sugaya Toshihiro , Morishita Naoki , Nakamura Naomasa , Suzuki Katsumi
Published: February 2023

An optical disk memory with a larger capacity and a higher data transfer rate than those of available optical disk drives is required for multimedia applications. The authors have developed a 600 MB capacity 90 mm phase change optical disk memory1) to achieve these two demands using a 690 nm laser diode, a 0.6 numerical aperture objective lens, a 0.6 mm thin substrate double–sided disk, and a fast auto laser power control technique2).
High Speed Magnetic Head Driver in Overwritable Magneto-Optical Disk Drive for Use of Magnetic Field Modulation Method
Authors: Fukui K. , Okamoto R.M. , Ishikawa H. , Matsumoto K.
Published: February 2023

The 130 mm Magneto-Optical (MO) disk cartridges with a capacity of 1.3 Gbytes have been standardized recently. Using the same disk as defined by the standard, except for the point of the disk being single sided, we have developed an overwritable MO drive featured by the magnetic field modulation method1)2), and mark position recording method. So, this MO drive maintains the compatibility with other drives. The data recording is carried out by the combination of constant laser beam irradiation and modulated magnetic field. This paper describes mainly upon the magnetic head driver used in our MO drive.
Lens Design Issues for Parallel Access to Optical Disks
Authors: Neifeld Mark A. , McDonald Mark
Published: February 2023

Parallel access to optical disks is a promising technique for increasing data transfer rate from mass storage and is a natural extension of optical imaging.[1] The nature of the lens design for parallel access is however, considerably different than for serial access and is primarily limited by aberrations and vignetting rather than by diffraction. Furthermore, tolerancing issues related to disk and head manufacture as well as environmental effects are more critical in the parallel access case and hence must play a greater role in design tradeoffs. In this paper we will discuss a number of design issues related to maximizing the parallelism associated with access to optical disk while maintaining low head mass to facilitate the increased difficulty of adaptive alignment (i.e. tracking, focus, tilt). The ultimate goal of this study is to achieve maximum aggregate data rate. Primarily, we will treat sustained data rate but the low mass characteristic of our designs will tend to improve tracking and seek times as well.
Modeling and Consideration on Crosstalks from adjacent tracks to realize high capacity recording
Authors: Kim Jin-Yong , Kim Dae-Young
Published: February 2023

The crosstalk, which is defined as interference noise in the readout waveform due to neighboring tracks, can become a major contributor to total noise, especially as track pitches get reduced in order to achieve higher recording density.
New Three-Dimensional Optical Storage-A Multilayer Architecture
Authors: Li Le , Faris Sadeg M. , Zarinetchi Farhad
Published: February 2023

Numerous problems in science and engineering require powerful computers with T-Byte capacities and data rates exceeding 1 Giga-bit/sec. In order to meet these requirements, new technologies are being investigated, including holographic and spectral hole burning storage concepts. However, these technologies must overcome many hurdles before they can be transferred to market. In this presentation, a novel idea that utilizes cholesteric liquid crystal (CLC) as the three dimensional data storage medium is proposed.
Light Weight Mini Disc Pick-Up
Authors: Shin H.K. , Ahn S.J. , Chang M.H. , Jung W.S. , Kim I. , Park N.K.
Published: February 2023

Recently, SONY has announced mini disc as the next generation of audio discs, and there is much attention on the system[1]. Since the diameter of mini disc is small (64 mm) compared with that of compact disc(120 mm), the size of the player is reduced small enough for the shirts pocket. As soon as SONY’s first mini disc player appears in the market, there has been a race for further miniaturization of player among several companies.
Super-Resolving Readout System using Optical Apodization and Electrical Equalization
Authors: Tanabe Takaya , Amano Norio , Arai Ryoichi
Published: February 2023

Super-resolving readout systems using an apodizer are effective for achieving high-density optical recording.1,2,3 These systems need additional optics that include a narrow slit and focusing lens for suppressing enlarged sidelobes. However, the added optics reduce the readout signal power and require precise positioning of the slit. In this study, we demonstrate a super- resolving readout system that employs an electrical equalizer instead of additional optics.
Signal-to-Noise Ratio Performance of Magneto-Optic Read Channels in Presence of Bloom
Authors: Ozgunes Inci , Vijaya Kumar B. V. K.
Published: February 2023

We modeled the MO channel in the presence of bloom, which is the thermal expansion or contraction of the written domains. We used the model developed to study the effect of bloom on the signal-to-noise ratio (SNR) of different detection schemes and established that bloom can cause a significant decrease in the SNR.
Electron Microscopy Evidence for Microsegregation in TbFe Sputtered Films for Magneto-Optical Recording
Authors: Kim M.J. , Bow J.S. , Carpenter R.W. , Kim Soon Gwang , Lee Seh Kwang , Kim Won Mok , Yoon Jong Shik
Published: February 2023

Magneto-optical (MO) recording offers a new dimension in erasable mass data stroage technology. Typical recording layers in presently used MO disks consist of rare earth-transition metal alloys enveloped by silicon nitride protective layers. Characteristic low media noise of amorphous TbFe-based alloys make them particularly attractive for use in MO disk recording layers. The synthesis/microstructure dependence for their performance is the subject of this research.
Margin Balance in L/G Recording on over 5 Gbit/in2 MSR Disk
Authors: Murakami Y. , Maeda S. , Takahashi A. , Sumi S. , Watanabe T.
Published: February 2023

We have been developed a magneto-optical (MO) disk drive system with over 6 GByte capacity in a 120mm-diameter single-side disk.[1] It utilizes a magnetically induced super-resolution (MSR) medium on a 0.6 mm-thickness substrate and land/groove (L/G) recording with an effective track pitch of 0.6 um. In this report, we will describe recording and readout margin balance between lands and grooves in the MSR disk system.
Tolerance Analysis of Near-Field Optical Recording System
Authors: Baoxi Xu , Chong Chong Tow , Minyu Liu , Boopathi V. , Gaoqiang Yuan
Published: February 2023

The near-field optical recording using solid immersion lens(SIL) is evolving as a promising technology towards high-density optical recording [1-5]. The high-density recording is achieved by introducing a high-index Solid Immersion Lens in between the recording medium and the objective lens, there by increasing the numerical aperture of the optical system. Birukawa et al[5] has analyzed the effect of deviation in SIL height and decenter on the focused beam spot position. However, the deviation from the ideal relative position of the SIL and the objective lens is a practical problem, which can cause serious wavefront aberration, and this will greatly affect the beam spot quality. In this paper, we analyze the aberration introduced due to lateral and longitudinal misalignment of the Supersphere Solid Immersion Lens (SSIL) with respect to the objective lens based on the wavefront aberration. The optical coupling efficiency of the SSIL lens to the recording layer is also analyzed.
MMVF Mastering for Exposure Processes & Simulation
Authors: Mukaida Masaru , Chaki Yuji , Katsuda Shinichi
Published: February 2023

Multimedia video file (MMVF), for which the target of recording capacity is 5.2GB/side, requires mastering technologies for fabricating fine preformat patterns having the specifications listed in Table 1. The most important mastering technologies are the following ones for optimization of the exposure processes.
Microstructure-Property Relationship in Nitrogen Doped Ge2Sb2Te5 Phase-Change Recording Media
Authors: Kim Myong R. , Seo Hun , Jung Tae H. , Park Jeong W. , Yeon Cheong
Published: February 2023

Phase-change optical data storage is basically based on the difference in optical properties between amorphous and crystalline phases of a recording medium. It has been known that the physical properties including reflectance and thermal conductivity of a material basically depend on the chemical composition of materials and their microstructure. Lately, the manipulation of chemical composition in GeSbTe-based chalcogenide that is one of the most promising candidate materials for phase-change recording medium was tried by doping a small amount of nitrogen in Ge-Sb-Te phase-change optical disks[1] From the earlier work, an enhanced media cyclability was achieved in PPM recording at the wavelength of around 780 nm. The goal of this research is to investigate the variation of thermal, optical and dynamic properties, and their correlation to microstructure in nitrogen-doped Ge2Sb2Te5 phase-change recording media. Primary endeavors focused on the dependence of nitrogen doping on crystallization temperature, reflectance, initializing power level, CNR and overwrite jitter at the wavelength of 650nm and pulse-width modulation (PWM) recording, leading to higher storage density.
Complex Plane Description of Differential Phase Detection in Optical Data Storage
Authors: Milster Tom D. , Upton Robert S.
Published: February 2023

Differential phase detection (DPD) utilizes the rotation of the total diffraction pattern that is collected in the exit pupil of an optical data storage system. By placing a quadrant cell detector in the exit pupil of the system, the DPD signal may be calculated as the phase difference that arises between the diagonal detector currents. Figure 1 is a schematic representing how the DPD signal is formed.
Edge detection readout signal and cross-talk in phase-change optical data storage
Authors: Peng Chubing , Mansuripur M. , Nagata Kenichi , Ohta Takeo
Published: February 2023

Conventionally, readout signal is obtained by differential detection in magneto-optical storage or by direct integration of the reflected light in phase-change optical storage. Mark edges are usually determined by slicing the level detection signal at the standard level, suffering from intersymbol interference when reading densely recorded short marks. Edge detection is a direct optical detection for mark edges. The readout signal is the difference signal from a split detector. Theoretically, edge detection has advantages over conventional level detection, such as high contrast and ability to identify edges of densely spaced marks. These features need to be confirmed experimentally. In magneto-optical storage [1], edge-shift of short marks using edge detection was found to be lower than that using differential level detection [2]. But in other aspects, such as signal and noise levels, edge detection was inferior to differential level detection [2, 3]. In phase-change optical storage [4], theoretical analysis indicates that edge detection has a potential superiority over conventional detection (hereafter referred to as sum detection). Experimentally, edge detection noise level has been confirmed to be lower than sum detection, especially at low and high spatial frequencies. In this work we present results for edge detection readout signal, carrier-to-noise ratio (CNR), and cross-talk characteristics in the scheme of land-groove as well as comparison with sum detection for phase-change optical storage.
Characteristics of MAMMOS read-out with magnetic field synchronized with embossed clock marks
Authors: Takagi N. , Yamaguchi A. , Sumi S. , Awano H. , Shimazaki K. , Ohta N.
Published: February 2023

MAMMOS (Magnetic Amplifying Magneto Optical System) read-out can achieve both high resolution and large signal simultaneously[1-4] and it is available for next generation MO systems. By using MAMMOS, a large signal can be obtained even at 0.2 μm packed domain[5]. In order to realize a high density digital video disk, we observed read-out characteristics of MAMMOS for modulated signal by taking synchronization with embossed clock marks.
Optical Disk Drives with Very Short Seek Time
Authors: Glaser I.
Published: February 2023

Rewritable optical disks offer high capacity and reliable removable media, yet they penetrated only small, niche, markets. When we compare the specifications of optical disk drives with those of non-optical magnetic 'hard'-disk drives, we see that the non-optical drives have over three times shorter seek time. With modern virtual memory systems like Unix, OS/2, Mac, or Windows NT, disk access time has strong effect on the overall system performance. If optical disks are ever to replace non-optical magnetic ones, they must be much faster.
Equalization For High Density Volume Holographic Storage
Authors: Vadde Venkatesh , Kumar B.V.K. Vijaya , Burr Geoffrey W. , Coufal Hans , Hoffnagle John A. , Jefferson C. Michael
Published: February 2023

Digital volume holographic storage architectures and techniques are being actively researched since they can provide high data rates and storage densities [1-2]. One of the many factors affecting storage density in the medium is cross-talk [3]. Typically, several stacks of multiplexed holograms are recorded in the storage medium. In order to eliminate inter-page cross-talk between adjacent stacks during read-back, an optical aperture is used. A smaller aperture permits one to closely pack hologram stacks and thereby achieve a higher density. However, in doing so, it introduces inter-symbol interference (ISI) through optical diffraction. The density versus ISI trade-off leads to an optimum aperture size, as we will show.
Modelling reversible optical data storage in photoanisotropic polymers
Authors: Pedersen Thomas Garm , Johansen Per Michael , Ramanujam P.S.
Published: February 2023

Among the potential materials for reversible optical data storage the liquid crystalline azobenzene side-chain polymers are especially promising due to their unique optical properties. Holograms of very high diffraction efficiency can be written (and erased) by laser illumination in this material and, equally important, the holograms are exceptionally stable. In order to clarify the mechanism responsible for these remarkable properties we have constructed a mean-field theory [1] of the storage process. It has been shown that the inter-molecular forces are essential for an understanding of the way in which holograms are gradually stored during illumination. An example of the comparison between theory and experiment is shown in Fig. 1. In addition, the mean-field theory has provided an explanation for the stability of the holograms. This explanation is based on theoretical results showing that the optical data are stored in entire domains rather than in individual molecules. Hence, the superior stability of a large domain in comparison to a single molecule is transferred to the optical hologram.
Holographic Recording of microscopic Bragg-reflectors for Optical Data Storage
Authors: Eichler H. J. , Kuemmel P. , Orlic S. , Wappelt A.
Published: February 2023

We report on the holographic recording and read-out of microscopic Bragg-reflectors in DuPont Omnidex HRF-800 photopolymer films with 20μm thickness. A Helium-Neon laser operating at λ = 632.8 nm was employed as light source. Lenses from Digital Versatile Disk (DVD) pick-ups were used to realize a beam waist with submicron diameter. The local distribution of the diffraction efficiency was investigated by applying a confocal scanning microscope setup. Holograms with a radius of 1.8 μm and 12μm depth have been recorded. Due to shrinkage, the maximum diffraction efficiency was 0.4 %, which can be improved by adjusting the read-out wavelength.
Holographic 3-D Disk using In-line Face-to-Face Recording
Authors: Saito Kimihiro , Horimail Hideyoshi
Published: February 2023

A holographic 3-D disk employing the shift multiplexing method has been presented in the reference [1]. The technology makes it possible to provide a 3-D holographic data storage system with existing 2-D disk technologies such as the focusing and tracking servo methods. However, the system requires two separate optical paths for spherical reference beam and planar object beam in order to create holograms on the media. In reference [2], another holographic disk recording/read-out method is proposed. In this method, a laser beam is focused inside a photosensitive layer with a reflecting unit underneath to generate a standing wave, by which an index grating is produced. This method, however, entails a problem: the reference light interferes with the reconstructed light on the image capture device. In this paper, we present a new recording/read-out method which solves the problems in the two methods mentioned above. The construction of the optical head, the structure of the media employing the new method and its experimental results will be presented.
Digital Holographic Memory using a Digital Micromirror Device SLM and a CMOS Active Pixel Sensor Camera
Authors: Campbell Scott , Curtis Kevin , Hill Adrian , Richardson Thomas J. , Tackitt Michael C. , Wilson William L.
Published: February 2023

During the past three decades holographic memory has received considerable attention as a possible massive data storage scheme. 1 In recent years, as system components (such as spatial light modulators and CCD or CMOS detector arrays) have matured, digital holographic memory systems have become realizable. This paper discusses in detail the performance characteristics of two such components, a digital micromirror device 2 (DMD) spatial light modulator (SLM) and a CMOS active pixel sensor 3 (APS) camera, in conjunction with the overall digital holographic memory (DHM) system in which they are employed.
Performance of High Density Optical Recording Disk Using Vacuum Evaporation Deposited Organic Dye Film
Authors: Tosaki Yoshihiro , Takahashi Katsuyuki , Hosaka Tomiharu , Kunieda Toshiaki
Published: February 2023

High density write-once disk is desired as the authoring medium for fully compatible DVD-ROM that is expected to create global standard medium for data storage and high quality motion picture.
Recurrent Neural Network Equalization (RNNE) for Partial Response (PR) Shaping of Magneto-optical (MO) Readback Signals
Authors: Ozgunes Inci , Hacıog̃ Kadri , lu  , Kumar B.V.K. Vijaya
Published: February 2023

PR equalization of MO readback signals using RNNE improves SNR performance over linear equalizer (LE), allowing threshold detector rather than LE+Viterbi Algorithm with comparable BERs.
Deep-learning-based cross-talk free and high-security compressive encryption with spatially incoherent illumination
Authors: Qin Yi , Wan Yuhong , Gong Qiong , Zhang Minghua
Published: February 2023

Incoherent optical cryptosystem is promising for its immunity against coherent noise and insensitivity to misalignment, and compressive encryption is desirable considering the increasingly demand on the exchange of encrypted data via Internet. In this paper, we propose a novel optical compressive encryption approach with spatially incoherent illumination based on deep learning (DL) and space multiplexing. For encryption, the plaintexts are individually sent to the scattering-imaging-based encryption (SIBE) scheme where they are transformed to scattering images with noise appearances. Afterwards, these images are randomly sampled and then integrated into a single package (i.e., ciphertext) by space multiplexing. The decryption is basically the inverse of the encryption, while it involves an ill-posed problem (i.e., recovering the noise-like scattering image from its randomly sampled version). We demonstrated that such a problem can be well resolved by DL. The proposal is radically free from the cross-talk noise existing in many current multiple-image encryption schemes. Also, it gets rid of the linearity bothering the SIBE and is hence robust against the ciphertext-only attack based on phase retrieval algorithm. We present a series of experimental results to confirm the effectiveness and feasibility of the proposal.
High-resolution fiber grating pressure sensor with in-situ calibration for deep sea exploration
Authors: Ji Lanting , Sun Qingquan , Zhao Shanshan , Yang Shuqing , Xu Jie , Su Juan , Wu Chi
Published: February 2023

A high-resolution and wide-range pressure sensor based on π phase-shifted fiber Bragg grating (π-FBG) encapsulated with metal thin-walled cylinder is reported. The sensor has been tested with a wavelength-sweeping distributed feedback laser, photodetector and a H13C14N gas cell. To perceive temperature and pressure synchronously, a pair of π-FBGs are glued on the outer wall of the thin-walled cylinder along the circumferential direction with different angles. The interference of temperature is effectively corrected by a high-precision calibration algorithm. The reported sensor has a sensitivity of 4.42 pm/MPa, a resolution of 0.036% full scale (F.S.), and a repeatability error of 0.045% F.S. in the range of 0-110 MPa that corresponds to an ocean depth resolution of 5 m and a measurement range of eleven thousand meters to cover the deepest trench of the Ocean. The sensor features simplicity, good repeatability, and practicability.
Fabrication of a 92cm Diameter Light-Weight F/2 Paraboloid Vacuum Ultraviolet Telescope Mirror
Authors: Muffoletto C. Verne
Published: February 2023

Fabrication of a 92cm diameter light-weight F/2 paraboloid vacuum ultraviolet telescope mirror to be utilized on an early Spacelab Mission for investigation of ultraviolet emissions from galaxies, stars, planets and comets from 900 Å to 2,000 Å will be discussed. Dr. William G. Fastie, of The Johns Hopkins University, will be Principal Investigator.
An Approach to Polishing Diamond Turned Optics
Authors: Parks Robert E.
Published: February 2023

This paper discusses an approach to the problem of reducing the scatter and improving the figure of a system of nonlinear diamond turned optics. Following a cosmetic polish to reduce scattered light, the components are assembled in their final mounts. After testing for system wavefront error, one of the optics is figured using a specially designed in situ semiautomatic polishing machine.
Space Telescope Mirror Substrate
Authors: Lewis William C.
Published: February 2023

NASA's Space Telescope calls for a concave-convex 98 inch diameter lightweight mirror substrate, The material chosen was Coming's Code 7971 ULE™ glass, which was fabricated into a 10 inch thick lightweight core faced with 1 inch thick front and back plates. ULF glass is manufactured by a very unusual process, and has some equally unusual properties. The manufacturing method is known as flame hydrolysis, in which silicon and titanium tetrachloride vapors are reacted in a flame to produce tiny molten glass particles. These particles are collected on rotating tables to form clear glass discs 60 inches in diameter and 5-6 inches thick, from which the substrate must be fabricated. Perhaps the most unusual property of ULE material is its weldability. Discs are sawed into thin slabs that are welded together in an open room to form inner and outer rings and a square-celled monolithic honeycomb core. Other discs are heated to 16006C and allowed to flow out to the needed diameter to produce the face plates. The entire assembly is sealed together at 1600°C and sagged to curvature to produce the rough blank, which is then annealed. Another unusual property is the linear correlation of the coefficient of thermal expansion (C.T.E.) and ultrasonic velocity. This permits non-destructive evaluation and documentation of the actual material used for the component parts, which assures that the final blank will meet the demanding requirements for homogeneity of C.T.E. as well as near-zero C.T.E.
The Buying and Specifying in Plastic Optics
Authors: Lytle John D.
Published: February 2023

If one has the slightest inkling that plastic (polymer) optics are well suited to a specific application, it is probably advisable to sit down immediately and prepare to rethink both the design and buying strategies. The reason is the medium itself represents a fairly radical departure from glass optics practice.
Ruling of Large Gratings
Authors: Gordon I.
Published: February 2023

A large grating ruling engine designed and constructed in the spectroscopic laboratory at M.I.T. in Cambridge is presently located at Kitt Peak National Observatory, Tucson, Arizona. Because of continuing interest in large gratings, a modest ruling program utilizing the M.I.T. 'C' engine is being conducted in Tucson. Contained herein is a description of the engine, its control and techniques in its operation.
Application of Zernike Polynomials to Reduction of Wavefront-Slope Data
Authors: Davis Nancy H. , Fritz Teresa A.
Published: February 2023

In testing optical surfaces, several very useful tests are those which depend on the slope of the surface These include the Hartmann test, Ronchi test, Foucault knife-edge test, and others.1
Fabrication Of A Scatterplate Interferometer
Authors: Rubin Lawrence F.
Published: February 2023

The phenomenon of fringes visible in scattered light was first observed by Newton. In his experiment, sunlight was passed through a pinhole positioned at the center of curvature of a back-silvered spherical mirror. What he saw centered about the pinhole was a series of colored rings that were greatly enhanced when the front surface of the mirror was dusted with a fine powder. As described by DeWitte,1 the principles used to explain the rings are similar to those used to describe the scatterplate interferometer.
Optical Shop Testing of High Quality Surfaces Using a Digital Interferometer
Authors: Mahany Richard E.
Published: February 2023

In order to assure the highest degree of performance in their finished products, manufacturers of photolithographic objectives for the microelectronics industry have found it necessary to employ advanced testing technology in their optical shops. This paper describes several practical uses of a direct phase measuring digital interferometer in a modern optical fabrication facility.
Ultra High Responsivity 3He-Cooled Bolometers
Authors: Goebel J. H. , Brooks W. F. , Kittel P.
Published: February 2023

We have designed and tested an ultra high responsivity liquid helium-3 refrigerated bolometer for use in low-background applications. The bolometer consists of a single germanium crystal 1/4 x 1/4 x 1/4 mm with contacts at diagonally opposite corners. A short length of gold wire (0.7 mil diameter) is bonded to the contact which is soldered to 5 mm lengths of 1/2 mil stainless steel wire. The other end of each of the stainless steel wires is bonded to a metallized diamond heatsink for the 0.3°K bath. Secondary heatsinking of incoming electrical leads is with indium buried copper transformer wire. The result is a high sensitivity yet fast (10 ms time constant) bolometer suitable for use in low background environments with PB < 250 pw.
Cleaning an Ar-Coated Mirror for Inspection
Authors: Eickelberg W. , Aiello T.
Published: February 2023

Summary not available.
High-Speed Polishing
Authors: Plummer J. L.
Published: February 2023

Summary not available.
Optical Mass Production In A First Generation Manufacturing Base. Potentials and Limitations !
Authors: Platt N. A.
Published: February 2023

The fabrication of Optical Elements began as an Art rather than a Science and has tended to remain so throughout its history. With demands of high quantity and quality, the fabrication procedures are under constant standardisation to approve upon yet cost-effective material, machinery and manpower.

Rollei Singapore (Pte) Ltd. (RS), a subsidiary of Rollei, Franke & Heidecke, West Germany, has grown into a mass manufacturer of high precision optical, optomechanical and photographic components/equipment in Singa­pore since 1970 with the majority of designs licensed by Carl Zeiss, West Germany.

The author projects Singapore's industrial structure and economic policies. He spot-lights RS for history, general policies, scope, spread and its versatility in a first generation manufacturing base.

The effect of major features, to that effect, viz., machinery and equipment used, technologies applied and control techniques observed are dilated. Particular stress is laid on applied modem cost-effective techniques of manufacturing processes ensuring reproduceability and reliability through the State of Art.
Handling the Turning of Machineable Thallium Salts
Authors: Schmit F. M. , Anderson R. H.
Published: February 2023

A ThI-ThBr compound known as KRS-5 is presently being investigated as a
forgeable IR optical material. The KRS-5 requires shaping before and
after the forging which could present operator exposure to the salt.
The toxicity of KRS-5 is within an order of magnitude to that of HCN
and therefore demands respect. A novel technique for machining the
KRS-5 is presented where all the turnings are removed from the lathe
without obscuring the operators line of sight. This "secure" fixture
allowed normal machining flexibility so various tooling could be
tried. The results are shown to be not only a safe lab but also a fine
machining job.
The Coaxial Equal Path Interferometer
Authors: Magner Joseph A. , Horwitz Joann B.
Published: February 2023

A new form of Equal Path Interferometer (EPI) will be described. As opposed to the usual form of EPI, the Coaxial Equal Path Interferometer (CPI) is designed to work on axis and is confocal. These factors, along with the other advantages of EPI's make the CPI very well suited for many difficult test situations. The advantages and adaptability of the CPI will be discussed. The performance characteristics will be presented along with some examples of interferograms obtained with the CPI.
Fabrication of Chemical-Vapor-Deposition ZnS and ZnSe Optical Components
Authors: Di Benedetto B. , Pappis J.
Published: February 2023

Summary not available.
Aspheric Mirror Metrology
Authors: Jones Peter A.
Published: February 2023

Aspheric mirrors utilized in optical systems have, by tradition, relatively slow focal ratios (f/2.6 to f/5.0). The 5.0-meter diameter Hale telescope primary mirror, for example, has a focal ratio of 3.3. Future ground based telescopes are being considered with aperture diameters in the range of 10 meters to 25 meters. In order to keep the telescope length and building within realistic sizes, primary mirror focal ratios ranging from f/1.0 to f/1.5 will be required. In a similar manner, packaging limitations for future space telescopes will force even faster primary mirrors (f/0.8 to f/2.3). The 2.4-meter diameter, f/2.3, Space Telescope primary mirror has a faster focal ratio than any current ground based telescope larger than 2.0 meters in diameter. Both fabrication (processing) and metrology (testing) are issues that must be addressed in the manufacture of these fast aspheric mirrors.
Computer-Controlled Otpical Manufacturing
Authors: Bajuk Daniel J.
Published: February 2023

Summary not available.
Tool Parameters in Diamond Turned Aspheric Optics
Authors: Weeks Richard F.
Published: February 2023

There is little doubt that single point machining technology will continue its rapid development in the immediate future. Today’s spindles, air bearing ways, and servo positioning systems are all significantly more accurate than their counterparts of as little as five years ago. Diffraction limited single point machined optics operating in the visible are not beyond contemplation. The one discouraging aspect to this otherwise optimistic picture is the diamond tools themselves. It appears to me that unless we focus the same kind of attention on the diamond tools that we have lavished on machines and operating techniques, cutting tools will soon be the major source of error in our optics. This is because we must have accurate tool parameters in order to calculate the tool path to cut a given surface.
Thermal-Kinematic Design Considerations
Authors: Smith Jack T.
Published: February 2023

Summary not available.
Building the Lens Mount Into the Lens!
Authors: Schmit F. M. , Anderson R. H.
Published: February 2023

Forged optics can include a mounting flange on the periphery of a
convex lens! This paper shows that a lens with a flat annulus on both
sides of the lens in included in an experimental forging program. The
lens diameter is larger than the required clear aperture by the
dimension of the shoulder and the lens thickness at the clear aperture
can be the shoulder thickness.. This shoulder is machineable allowing
post forging adjustments on air gap and centration. The possibility of
threading the outside of the shoulder allows for a whole new
generation of lens mounting technology.
High-Volume, High-Quality Optomechanical Interface
Authors: Plummer John L.
Published: February 2023

Summary not available.
A Hard Gold Optical Coating
Authors: Epner David
Published: February 2023

This paper will trace the development of a hard gold electro-deposited coating that was originally developed to solve an engineering problem for Xerox. The plating bath variables that were considered and those that were eventually decided upon will be treated. Test procedures and results for both hardness and reflectance will be illustrated. Applications of this gold coating for mirrors, reflectors, integrating spheres, and diffraction gratings will be discussed. Design considerations, such as its ability to be deposited over glass as well as metal substrates and its diamond machine ability, will be touched upon.
Specifying the Finish of Diamond-Turned Optics — Problems and Possibilities
Authors: Bennett J. M. , Rahn J. P. , Archibald P. C.
Published: February 2023

Single-point diamond machining is a versatile technique for producing metal optics in conventional as well as unusual shapes. The diamond-turning process is now well enough controlled that high quality, low scatter surfaces can be produced. However, the grooved nature of the surfaces makes it difficult to specify the surface finish and to relate measured roughness values to the performance of a diamond-turned component in an optical system. Specifically, the distribution of the angular scattering from a diamond-turned surface is drastically different from that of a normal polished surface, and the angular scattering can vary greatly from sample to sample.
Processing Metal Mirrors for Dimensional Stability
Authors: Paquin Roger A.
Published: February 2023

The metal mirror processing methods used today frequently produce mirror surfaces with "locked-in" stresses that eventually lead to expensive surface rework for a finished optical product. This paper focusses on the optical fabrication process where improvements in mirror blank manufacturing can be made which produce stable optical surfaces operable under severe environmental variations for long periods of time.
Optical Finishing Techniques
Authors: Shaffer J. J.
Published: February 2023

The past history of bowl-feed polishing is addressed – from its origin (before World War II, when it was used for high-speed, high-production work) to its present status. This history includes the shift in emphasis from high-speed, high-production goals to supersmooth-surface goals, a shift which took place in the mid-1960's. Techniques are offered for those opticians/technicians who desire to start using bowl feed. Formulae are given for polishing and blocking pitches.
Development of a New, Small Shack Interferometer
Authors: Palmer Eric M.
Published: February 2023

The model P-1 Shack Interferometer is a compact unequal path laser interferometer which we have made smaller than our previous instruments of this type by building it from smaller components. This new version has larger numerical aperture, cleaner beam, more stable alignment and greater versatility than earlier units. Its versatility, portability, low cost and ease of use make it attractive to the practicing optical technician and the competitive shop manager.
Test And Evaluation Of Large Aspheric Telescope Mirrors
Authors: Montagnino L. , Arnold R. , Slomba A.F.
Published: February 2023

The manufacture of a large diffraction-limited aspheric primary mirror encompasses several state-of-the-art processes. These include computer controlled polishing and interferometric test and evaluation. To advance manufacturing processes to the levels required for today's telescope systems and to meet future needs, full-aperture and sub-aperture interferometric test configurations have been developed in conjunction with a precision interferogram analysis facility.
Low Scatter Molybdenum Surfaces
Authors: Bennett J. M. , Archibald P. C. , Rahn J. P. , Klugman A.
Published: February 2023

Molybdenum (Mo) mirrors are being used in many high power infrared lasers and are also candidates for lasers operating in the visible and ultraviolet spectral regions. However, a limiting factor is the scattered light from the mirror surface which adversely affects the operation of the laser and can prevent the laser from operating at all. It has previously been shown1 that the surface finish obtainable on Mo mirrors is directly related to the grain structure of the material. Profile roughnesses in the 40 - 60 Å rms range are generally measured for well polished Mo surfaces, although total integrated scattering (TIS) measurements2 yield effective roughnesses in the 15 - 25 Å rms range for these same surfaces. (The difference between these two roughness measurements is caused by the different range of spatial wavelengths, and will be discussed later in this abstract.)
High Reflectance Measurements Using the Cavity Phase Shift Method
Authors: Kwok M.A. , Herbelin J.M. , Ueunten R.A. , Segal G. I.
Published: February 2023

The cavity phase shift (CAPS) method shows promise for direct measurements of high reflectances on various spherical surfaces at reasonable spatial resolution (1mm). The unknown reflectance is placed in an high Q optical interferometer, through which an intensity modulated laser beam is passed. A phase shift in the sine wave modulation yields the direct measurement. The multi-pass nature of an interferometer causes increased sensitivity and precision as the reflectances improve. Previous work with this approach has been done in the visible region. 1,2 This work has included the abilities to detect high transmittances or low absorbance-scattering in optical mirrors.
Hygroscopic Crystals
Authors: Ruderman Warren
Published: February 2023

Hygroscopic crystals present unique handling, polishing, coating and storing problems. However, the increasing use of these crystals in electro-optics and in harmonic generation and mixing, has led to advances in fabrication techniques.
Fabrication of a Large Thin Hexagonal Mirror Segment With a Spherical Surface of Precisely Defined Radius of Curvature
Authors: Nelson Jerry E. , Mast Terry S.
Published: February 2023

The status of the fabrication of a large thin hexagonal mirror is described. The mirror will be used in a prototype of the segmented mirror control system for the proposed University of California Ten Meter Telescope. The telescope design calls for a semented primary mirror with thirty-six 1.8-meter diameter hexagonal segments. Each segment will be made to a precisely defined surface with a precisely defined radius of curvature (35m) such that the rms deviation from the ideal surface is less than 30 nanometers.
Trends in Optical Materials
Authors: Detrio John A.
Published: February 2023

The trend in optical materials can be easily and accurately predicted -- optical materials will be better, cheaper, and more complex in the future. This summary may be too simple and perhaps all of these trends will not be true of all optical material. However, recent experience shows that significant progress has been made in preparing high quality optical materials. Especially impressive are the solid state laser host materials which include single crystals and glasses and optical components for infrared lasers fabricated from alkali halides, alkaline earth fluorides, sapphire, and CVD ZnSe. Demands for low cost molded optics for consumer products have lead to the expanded use of plastics and the development of precision molding processes. Similar trends are developing for infrared optics; for example, the pressing of lenses. Aspheric surfaces machined by single point diamond turning are an example of the improved capability for producing complex components. Sol gel, MBE techniques for the production of graded index antireflection coatings, surface strengthening of optical materials and the production of gradient index optics are emerging materials processes that will probably play a growing role in the fabrication of optical components.
Trends In Computer-Controlled Polishing
Authors: Jones Robert A.
Published: February 2023

Computer-controlled polishing has been used for numerous grinding and percision figuring efforts. Futher activity will include further progress in those areas plus new applications.
Trends in Optical Testing Technology
Authors: Koliopoulos Chris
Published: February 2023

A discussion is given of the development of interferometric techniques coupled with computer technology for precision optical metrology. Contemporary examples of uses of these methods in optical manufacturing and the capabilities they offer are presented. A brief look is given at possible future developments including the problems of aspheric testing.