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Proceedings of the 1999 3rd International conference on optical Information Processing

作者： Armenise, Mario N. Passaro, Vittorio M.N. Armenise, Michele Diana, Roberto Politecnico di Bari Bari Italy

A great research effort has been spent in recent years for the use of guided-wave optoelectronic technologies for signal processing in space applications, because they allow to reduce size, weight, power consumption and system complexity with respect to electronic ones. Based on these motivations, we have conceived, designed and simulated a number of original integrated optical signal processors, such as two-dimensional correlators for imaging reconstruction in Synthetic Aperture Radar (SAR) applications, both airborne and spaceborne (using either a hybrid or monolithic approach), preprocessors for data classification and identification in satellite applications for remote sensing, beam formers and steerers in active phased array antennas (using either the acousto-optic or electrooptic effect), heterodyne spectrum analyzers, and so on. The substrate materials considered for these circuits are both ferroelectric (*** niobate) and III-V semiconductor materials (*** arsenide and its compounds). Original modelling and numerical techniques have been developed to analyze and design the guided-wave components included in the optical architectures. In this paper, the most significant developments of this research activity are reviewed.

关键词： optical waveguides

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Telepathology system for microscopic images utilizing super high definition imaging system over B-ISDN

Telepathology system for microscopic images utilizing super ...

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conference on Image Display at Medical Imaging 1999

作者： Okumura, A Furukawa, I Fujii, T Ishimaru, K Sakano, T Suzuki, J Ono, S Hata, J Ashihara, T NTT Optical Network Systems Labs. (Japan) Keio Univ. School of Medicine (Japan) Kyoto Prefectural Univ. of Medicine (Japan)

ISBN: (纸本)0819431303

It has been recognized early on that digitizing medical information makes diagnostic technology more advanced and efficient. In order to convert image information, which comprises the majority of all medical information, into digital data, various technologies including those for input, processing, transmission storage, and display need to develop at roughly the same pace. To date, there have been few cases where this has been done. However, recent major advances in high-resolution image input/output, image encoding, super-fast transmission, high-capacity storage, and other technologies have intensified the drive towards digitizing and networking all medical information. This paper will show that the spread of super-high-speed networks capable of transmitting large amounts of data in a short time is indispensable for accurate medical diagnosis, and that this will make it possible to realize an integrated medical information system. A target application for the medical image diagnosis of the Super High Definition (SHD) images being developed by the authors of this paper is telepathology, which particularly demands high-quality images. In this paper, we will study, among other things, the concrete issues crucial to building and networking a digital system and the approach to resolving such issues. We will also report on the building of our experimental system that fulfils such demands as well as discuss a pathological microscopic image transmission system with image quality that will not lower diagnostic accuracy and fast response and good operability that will not make diagnosticians feel impatient. Finally, we will discuss a test in which we remotely operated a microscope over an ATM line to prove that it is possible to capture, transmit, and display a still super-high-definition digital image with a resolution of 2,048 x 2,048 pixels in about 5 seconds.

关键词： pathological microscopic images super-high-definition (SHD) images telemedicine telepathology ATM (Asynchronous Transfer Mode) image transmission B-ISDN (Broadband-Integrated Services Digital Network)

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Tungsten oxide based media for optical data storage and switching applications

IEEE Aerospace Applications Conference Proceedings

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IEEE Aerospace Applications conference Proceedings 1999年 3卷 343-349页

作者： Bussjager, Rebecca Osman, Joseph M. Voss, Ethan Chaiken, Joseph Air Force Research Lab Sensors Directorate Rome United States

We report recent research into laser chemical processes involving tungsten oxide and similar materials having applications in optical data storage and switching. The basic properties of these processes and media are presented with particular attention being directed towards switching times, threshold power requirements and choices of process wavelengths. These characteristics define the architectures of both individual storage and switching devices as well as systems composed of these devices. We discuss these characteristics in terms of available components for implementing actual devices and systems. Finally, tungsten oxide technology will be presented in the context of competing magneto-optic and phase change technology.

关键词： optical materials

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Fast edge map extraction from MPEG compressed video data for video parsing

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Proceedings of SPIE - The International Society for optical Engineering 1999年 3656卷 710-721页

作者： Song, Byung Cheol Ra, Jong Beom Korea Advanced Inst of Science and Technology Taejon Korea Republic of

For the last few years, shot boundary detection has been recognized as an important research issue on video retrieval. Also as a preliminary step for the task, it is essential to extract salient features from videos. Recently, it has become common to perform the two tasks in compressed domain to alleviate their computational costs. In this paper, we propose novel shot boundary detection technique, which uses two feature images, or DC and edge images, extracted directly from MPEG compressed video. While a DC image can be easily obtained, edge image extraction usually requires considerable computational burden. For fast edge image extraction, we suggest to utilize only a few AC coefficients of each DCT block in motion compensated P-frames and B-frames as well as I-frames. This drastically reduces the computational burden compared to edge extraction in the spatial domain. In order to further reduce the computational burden, another edge image extraction technique is also suggested on the basis of AC prediction using DC images. By using the edge energy diagram obtained from edge images and histograms from DC images, shot boundaries such as abrupt transitions, fades, and dissolves are detected automatically. Simulation results show that the proposed techniques are fast and effective.

关键词： Feature extraction

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UV-optical and microstructural properties of MgF₂-coatings deposited by IBS and PVD processes

UV-optical and microstructural properties of MgF<sub>2</sub>...

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conference on advances in optical Interference Coatings

作者： Ristau, D Arens, W Bosch, S Duparré, A Masetti, E Jacob, D Kiriakidis, G Peiró, F Quesnel, E Tikhonravov, A Laser Zentrum Hannover D-30419 Hannover Germany

ISBN: (纸本)0819432121

In high quality optical coating systems for the DUV-spectral range, MgF2 is one of the preferred deposition materials [1]. MgF2-coatings exhibit relatively low optical losses as well as high stability and laser induced damage thresholds. In the present joint research effort of several European laboratories, the potentiality of MgF2 is evaluated in respect to the production of improved optical coatings for applications in laser technology and semiconductor lithography. For this purpose, single, layers of MgF2 were deposited on superpolished fused silica and CaF2-substrates by ion beam sputtering (IBS, [2]), boat (bPVD) and e-beam (ePVD) evaporation in different laboratories. Besides photometric inspections, the samples were characterised by an optical scatter measurement facility at 193 nm [3] and 633 nm. The structural properties were assessed using AFM, XRD, and adapted TEM-techniques involving conventional thinning methods for the layers. For the measurement of mechanical stress in the coatings, special silicon substrates were coated and analysed. The optical constants of the MgF2-layers, which were determined by two independent data reduction algorithms from the spectral behaviour, are in good agreement with values published in the open literature [4]: The refractive indices range between 1.40 and 1.41 at 248 nm for the PVD and IBS processes. The IBS-process achieves best homogeneity and lowest surface roughness around 1 nm(rms) among the processes compared. In contrast to PVD coatings, which exhibit tensile mechanical stress ranging approximately from 300 to 400 MPa, high compressive stress of up to 910 MPa occurs in the IBS-coatings. The experimental findings are discussed in respect to the microstructural properties and the surface topography of the coatings [5].

关键词： MgF2-coatings ion beam sputtering (IBS) physical vapor deposition (PVD) DUV-spectral range total scattering

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High-density, high performance data storage via volume holography

High-density, high performance data storage via volume holog...

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conference on Lasers and Electro-Optics (CLEO)

作者： W.L. Wilson K. Curtis M. Tackitt A. Hill T. Richardson S. Campbell C. Boyd M. Schilling Bell Laboratories Lucent Technologies Inc. Murray Hill NJ USA

Summary form only given. It has long been known that volume holography allows multiple pages of data to be stored in the same volume, therefore allowing densities exceeding the diffraction limit for 2-dimensional optical storage. The attraction, is storage of individual Mbit data pages addressed by changing either the angle, wave-length, or phase code of the reference beams, resulting in the rapid parallel storage and retrieval of digital data. Although this technology has been proposed since the 1970's it has failed to achieve viability. Our team has made great strides toward resolving the key problems with the technology. First, a new series of methods for recording multiplexed holograms has been developed. These techniques can be implemented with an uncomplicated mechanical geometry, individual holograms are addressed by a simple translation of the media. In addition, for one particular technique, phase correlation multiplexing is reported.

关键词： Memory Holography Optimized production technology Holographic optical components Error correction codes optical films CMOS technology Detectors optical polymers optical diffraction

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Free space optical interconnect for Terabit network elements

Free space optical interconnect for Terabit network elements

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Optics in Computing, OC 1999

作者： Goodwill, Dominic J. Nortel Networks Advanced Design Technology NSPaN - Nortel Subsystems and Performance Networks PO Box 3511 Station C OttawaONK1Y 4H7 Canada

ISBN: (纸本)1557525846

Infrared data interconnects using freespace optics will simplify the deployment and physical design of Gigabit hubs and Terabit switch/routers. Infrared links range from the 4 Mb/s diffuse LED links found today in many laptop computers, to potentially 40 × 2.5Gb/s using parallel collimated VCSEL beams. Early deployment of multiple 1.25 Gb/s infrared links is expected. Complete free-space optical backplanes of multi-Tb/s capacity face extensive challenges, and may remain non-competitive with electrical backplanes, which already offer several Tb/s throughput. Supporting our roadmap, we have built discrete Gigabit Ethernet 1.25 Gb/s links using gently-diffusing VCSEL beams. We have developed 4 x 1.25 Gb/s transceivers using redundant VCSEL and detector arrays that provide real-time auto-alignment. With these two advances, we avoid the complex mechanics and moving parts that have to date prevented the deployment of parallel Gigabit infrared interconnects. © 1999 OSA/OC 1999.

关键词： optical fibers

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A new type of magneto-optical card

A new type of magneto-optical card

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International conference on Magnetics (INTERMAG)

作者： Chengtao Yang Qihua Fan Hongyou Chen University of Electrical Science and Technology of China Chengdu China

ISBN: (纸本)0780355555

Recording cards are widely used for date storage, laser cards and magnetic cards are very convenient, but the data rewriteable and high-density storage can not be compatible. The magneto-optical card has the advantage of high-density of laser recording and rewritable of magnetic recording. It uses the thermomagnetic principle to write data and the magneto-optical effect to read data, because of the no-contact reading/writing and the high-density of laser recording, the rewriteable laser card has potentially huge applications.

关键词： optical recording Power lasers Temperature dependence Servomechanisms Mechanical systems Servomotors Diode lasers Magnetic heads Identity-based encryption Magnetic materials

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Projection market and technology perspective: Where could lasers fit?

Projection market and technology perspective: Where could la...

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Proceedings of the 1999 12th Annual Meeting IEEE Lasers and Electro-Optics Society (LEOS'99)

作者： Kahn, F.J. Kahn Int Palo Alto United States

The $8 B (1999) electronic projector market is a major growth industry. Light sources and illumination systems are critical components and product differentiators. Opportunities for laser light sources are defined through discussion of projector market trends and metrics. Major technology and market trends that are expected to generate a $12 B electronic projector market by 2004, including 100% 1998-2004 growth in business projectors, are reviewed in the perspective of recent product introductions. A log linear analysis shows that the light outputs of benchmark transportable data video projectors have increased at a rate of almost 90% per year since 1993. The list prices of these same projectors have decreased at a rate of over 40% per year. The tradeoffs of light output vs. resolution and weight are illustrated. Recent trends in projector efficacy vs. year are discussed. Lumen output per dollar of list price is shown to be a useful market metric. Continued technical advances and innovations including higher throughput light valve technologies with integrated drivers, brighter light sources, field sequential color, integrated- and micro- optical components, and aerospace materials are likely to sustain these trends. The new technologies will enable projection displays for entertainment and computer applications with unprecedented levels of performance, compactness, and cost-effectiveness. Opportunities for lasers in mainstream projection systems will require properties commensurate with these trends. These can include ways to make higher image quality, lighter, cheaper, more rugged, longer lived, or more reliable projection systems than can be achieved with conventional light sources.

关键词： optical projectors

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Tungsten oxide based media for optical data storage and switching applications

Tungsten oxide based media for optical data storage and swit...

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IEEE conference on Aerospace

作者： R. Bussjager J.M. Osman E. Voss J. Chaiken Sensors Directorate Air Force Research Laboratory Rome NY USA Department of Chemistry and Keck Center for Molecular Electronics Syracuse University Syracuse NY USA

We report recent research into laser chemical processes involving tungsten oxide and similar materials having applications in optical data storage and switching. The basic properties of these processes and media are presented with particular attention being directed towards switching times, threshold power requirements and choices of process wavelengths. These characteristics define the architectures of both individual storage and switching devices as well as systems composed of these devices. We discuss these characteristics in term of available components for implementing actual devices and systems. Finally, tungsten oxide technology is presented in the context of competing magneto-optic and phase change technology.

关键词： Tungsten Memory optical sensors Biomedical optical imaging Chemical lasers Chemical sensors Chemical processes optical materials Magnetooptic devices Magnetic materials

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