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Conference on Lasers for Measurements and Information Transfer 2007

作者： Evdokimov, M. E. Victor Balt State Tech Univ St Petersburg Russia

ISBN: (纸本)9780819472168

In this article, I attempt to examine the systems with optical-television feedback branch operation. My study is based on multi-dimensional description of hybrid image processing systems. We analyze the influence of delay in feedback branch on the transfer function, give calculations of transfer function and output signal for iteration algorithm of hybrid system operation. Then we show the influences of finite iteration repetition and truncation of signal. Some ways to modify basic structure of hybrid systems is also proposed in order implement inverse filtration taking in consideration delay in feedback branch.

关键词： image processing Cameras CCD cameras Channel projecting optics Transient nonlinear optics digital signal processing Televisions image filtering Convolution optical amplifiers

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Active pixel concept combined with organic photodiode for imaging devices

IEEE ELECTRON DEVICE LETTERS

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IEEE ELECTRON DEVICE LETTERS 2007年第10期28卷 893-895页

作者： Tedde, S. Zaus, E. S. Fuerst, J. Henseler, D. Lugli, P. Siemens AG D-91058 Erlangen Germany Tech Univ Munich D-80333 Munich Germany

The active pixel concept is a promising architecture for imaging systems. We report on the electrooptical characterization of a hybrid organic active pixel sensor (APS) where an organic photodiode is integrated on top of an amorphous silicon thin-film transistor circuitry, which drives the image sensor and performs the signal processing. The active pixel approach provides an on-pixel amplification of the signal with a charge gain of up to 10. A fill factor that is close to 100% is obtained by embedding all transistors underneath the organic photodetector. We show that, as compared with organic passive pixels, the organic APS shows a higher sensitivity, making the detection of smaller signals possible.

关键词： active circuits image sensors optical imaging optical polymers optoelectronic devices photodetectors photodiodes plastics

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Advanced optical Processor for Arbitrary Waveform Radar Imaging

Advanced Optical Processor for Arbitrary Waveform Radar Imag...

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Sensor Array and Multichannel signal processing Workshop

作者： K. Frampton J. Lafuse J. Aloi M. Brown Essex Corporation Columbia MD USA

Essex has developed a prototype hybrid optical/digital processor for range-Doppler image formation using wideband arbitrary waveforms. The processor is called the advanced optical processor (AOP) and is a hybrid acousto-optic/digital processor that generates high dynamic range, range-Doppler images from wideband radar returns in real time. The AOP was first tested at a U.S. Government facility in November 2005. The AOP is currently scheduled to be tested with a range radar in April 2006. The laboratory testing included three waveform types and verification of all the necessary trigger control signals. The range radar testing will include collection and processing of the same three waveform signals to demonstrate arbitrary waveform capability. The AOP supports high resolution processing necessary for target discrimination and kill assessment by enabling the use of true arbitrary wideband waveforms. The selected architecture combines the advantages of both optical signal processing for the front-end receiver and high-speed digital signal processing for the real-time processing. Its size is a 6U form-factor and fits within the 6U electronic chassis

关键词： Laser radar Radar imaging optical receivers optical signal processing High speed optical techniques Acoustic testing Wideband Prototypes hybrid power systems Dynamic range

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Applications of spatial light modulators in optical signal processing systems

Applications of spatial light modulators in optical signal p...

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Opto-Ireland 2005 Conference

作者： Monaghan, DS Gopinathan, U Hennelly, BM Kelly, DP Naughton, TJ Sheridan, JT Univ Coll Dublin Dept Elect & Elect Engn Dublin 4 Ireland

ISBN: (纸本)0819458120

Coherent optical signal processors, due to their ability to process and relay information in two dimensions, have been receiving increasing attention in recent years. These systems involve a coherent field being propagated through some bulk optical system consisting of thin lenses and sections of free space (such paraxial systems being described mathematically using the Linear Canonical Transformation). A Spatial Light Modulator (SLM) may be used to modulate the input digital data onto a coherent wave-field as well as to modulate the amplitude and/or phase of the complex wave-field at any desired plane. The complex field (amplitude and phase) at any desired plane may be recorded quantitatively using a CCD camera, using digital holographic techniques allowing the further processing of data digitally. Such hybrid optoelectronic systems have applications for 2D and 3D data processing covering fields as diverse as data storage, data security and pattern recognition. But devices such as SLMs and CCD cameras can represent only discrete levels of data necessitating a quantisation of continuous valued analog information. In this paper, we take the example of an optical system used to encrypt 2D and 3D data and evaluate the effect of the finite discrete levels of an SLM on the encryption/decryption process.

关键词： Spatial light modulators image encryption Quantization optical signal processing Transform theory Wigner distribution functions digital holography signal processing Data processing Free space

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optoelectronic feedback circuit systems for signal processing of high-resolution images for target tracking

Optoelectronic feedback circuit systems for signal processin...

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11th IEEE digital signal processing Workshop/IEEE signal processing Education Workshop

作者： Raglin, A Vorontsov, M Chouikha, M Army Res Lab Adelphi MD 20783 USA

ISBN: (纸本)0780384342

Techniques for tracking targets in high-resolution images is an important task. However, computations for processing these types of images can be intensive. With recent advancements in LC devices, DSP, and VLSI alternate methods are being explored. One of these methods is the use of hybrid optoelectronic architecture. By combining the parallel nature of optics and the processing capabilities of electronics (DSP/VLSI) these system have the potential for providing fast and compact systems for detecting and tracking targets. A unique feature of these optoelectronic systems is a variety of spatial patterns that can be generated, one is the soliton pattern. This soltion pattern can be used to represent the location of a target within a image. In this paper, simulations of the system show trajectories of solitons indicating tracking of the target.

关键词： signal processing

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Missile signal processing common computer architecture for rapid technology upgrade

Missile signal processing common computer architecture for r...

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Conference on Advanced signal processing Algorithms, Architectures, and Implementations XIV

作者： Rabinkin, D Rutledge, E Monticciolo, P MIT Lincoln Lab Lexington MA 02420 USA

ISBN: (纸本)0819454974

Interceptor missiles process IR images captured by a focal plane array for locating and guiding the interceptor toward an intended target. A typical interceptor signal processing chain comprises two parts. Front-end video processing operates on all pixels of the image and performs such operations as non-uniformity correction (NUC), image stabilization, frame integration and detection. Back-end target processing, which tracks and classifies targets detected in the image, performs such algorithms as Kalman tracking, spectral feature extraction and target discrimination. signal processing requirements increased as sensor bandwidth increases and interceptors operate against more sophisticated targets. In the past, video processing was implemented using ASICs or FPGAs because computation requirements exceeded the throughput of general-purpose processors. Target processing was performed using hybrid architectures that included ASICs. DSPs and general-purpose processors. The resulting systems tended to be very function-specific, and required custom software development. These systems were developed using non-integrated toolsets, and test equipment had to be developed along with the processor platform. The lifespan of the interceptor platform on which the signal processors operate often spans decades, while the specialized nature of processsor hardware and software makes it difficult and costly to upgrade. As a result., the signal processing systems often run on outdated components, signal processing algorithms are difficult to update. and system effectiveness is impaired by the inability to rapidly, respond to new threats. A new design approach to interceptor signal processing is made possible by three developments: Moore's Law - driven improvement in computational throughput;a newly introduced vector computing capability in general-purpose processors and a modern set of open interface software standards. Today's multiprocessor commercial-off-the-shelf (COTS) platforms hav

关键词： signal processing digital signal processing Target detection Detection and tracking algorithms image processing Standards development MATLAB Commercial off the shelf technology signal to noise ratio Software development

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optoelectronic feedback circuit systems for signal processing of high-resolution images for target tracking

Optoelectronic feedback circuit systems for signal processin...

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IEEE digital signal processing Workshop

作者： A. Raglin M. Vorontsov M. Chouikha Army Research Laboratory Adelphi MD USA Howard University College of Medicine Washington D.C. DC USA

Techniques for tracking targets in high-resolution images is an important task. However, computations for processing these types of images can be intensive. With recent advancements in LC devices, DSP, and VLSI, alternate methods are being explored. One of these methods is the use of a hybrid optoelectronic architecture. By combining the parallel nature of optics and the processing capabilities of electronics (DSP/VLSI) these system have the potential for providing fast and compact systems for detecting and tracking targets. A unique feature of these optoelectronic systems is a variety of spatial patterns that can be generated, one is the soliton pattern. This soliton pattern can be used to represent the location of a target within an image. In this paper, simulations of the system show trajectories of solitons indicating tracking of the target.

关键词： Feedback circuits signal processing Target tracking digital signal processing Very large scale integration Computer architecture optical feedback optical signal processing optical solitons Trajectory

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Parallel optical interconnects with mixed-signal OEIC and fibre arrays for high-speed communication

Parallel optical interconnects with mixed-signal OEIC and fi...

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Conference on Micro-Optics, VCSELs, and Photonic Interconnects

作者： Fey, D Hoppe, L Loos, A Förtsch, M Zimmermann, H Univ Jena Inst Comp Sci D-07743 Jena Germany

ISBN: (纸本)0819453765

We present a system for direct parallel optical data communication between integrated circuits on neighboured printed circuit boards based on a monolithic integrated CMOS smart pixel array, fibre arrays, and VCSELs. The advantage of our system versus backplane systems is the direct data transfer through the space avoiding planar and area consuming interconnections. The detector chip allows a data rate of 625 Mbit/s per link and is cycled by an optical clock. A simulation of the chip layout showed 260 % more performance versus electrical off-chip interconnects. In principle an 8x8 data transfer is feasible allowing a data rate of 40 Gbit/s. The detector combines an optical receiver array with a digital processor array which executes image processing algorithms. The optical receiver is formed by a PIN photodiode with a diameter of 40 mum, a transimpedance amplifier (TIA) and a decision-making postamplifier. The measured responsivity of the photodiode without antireflection coating is R=0.382 A/W at an optical wavelength of 670 nm. The TIA consists of a CMOS inverter and a PMOS transistor forming the feedback resistor. Together with the postamplifier, formed by a chain of five CMOS inverters and attaining digital CMOS levels, a data rate of 625 Mbit/s is achieved.

关键词： photonic interconnects smart pixel architectures fibre arrays CMOS photodetectors optoelectronic VLSI

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High-speed optical interconnect demultiplexing at the Fresnel plane

High-speed optical interconnect demultiplexing at the Fresne...

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4th Optomechatronic systems Conference

作者： Rivera-López, FD Treviño-Palacios, CG Tepichín-Rodriguez, E Inst Nacl Astrofis Opt & Elect Puebla 72000 Mexico

ISBN: (纸本)0819451525

High speed remote radio control of systems containing multiple elements is usually performed using control channels for individual elements with multiple emitters and receivers at different conduits. If these signals are multiplexed and transmitted, the bandwidth of each individual channel is reduced depending on the number of required channels. We propose a hybrid system that allows demultiplexing on flight time using a spatial light modulator to route the incoming signal into different out ports. The control signals are first multiplexed in frequency and the low speed routing control signal modulates it in amplitude. The combined signal is used to drive a diode laser. The proposed demultiplexing apparatus consists on a double 4f optical system in which the image of a dynamic liquid crystal display is imaged on the Fresnel plane. The control signal displays an amplitude binary mask on the dynamic spatial light modulator to route the signals to individual detectors located at the Fresnel plane in order to recover the individual channels. Afterward each channel is individually recovered. In order to demonstrate this system, multiple CATV signals were multiplexed with a digital control signal used to amplitude modulate the diode laser and tested on an optical bench. We also present the advantages of using such optical interconnects on the Fresnel plane over the Fraunhoffer plane.

关键词： signal processing linage processing optical computing and information processing

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A new frequency processing algorithm based on multiresolution analysis

A new frequency processing algorithm based on multiresolutio...

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Medical Imaging 2003 Conference

作者： Kaji, D Sato, C Kano, A Tsuchino, H Konica Corp R&D Ctr Med & Graph Co Hino Tokyo Japan

ISBN: (纸本)0819448303

The purpose of this study was to develop a new frequency processing algorithm based on multiresolution analysis, a common method of signal analysis, and thus to improve the diagnostic image quality of digital x-ray imaging systems such as computed radiography (CR). The newly developed algorithm, termed "hybrid processing", has three unique features. First, the original image is decomposed into plural frequency bands, and each frequency component is weighted and added back to the original image. Second, at the decomposition stage, rather than employ a conventional simple averaging filter, a binomial filter is used to create unsharp images. Third, an enhancement characteristic is established for each unsharp image based on a smooth compensation function predetermined by the density and contrast of the unsharp image. hybrid processing was applied to approximately 500 clinical CR images, including images of the chest, abdomen, and extremities. image decomposition, and the weighting and re-addition of its frequency components produced optimal renditions from low through high frequencies. Further, the binomial filter provided smooth frequency response with a reasonably short processing time. Combined with the enhancement characteristic established for each unsharp image, the binomial filter effectively reduced unfavorable noise enhancement and such artifacts as overshoot and undershoot.

关键词： computed radiography digital x-ray image multiresolution analysis frequency processing density contrast binomial filter

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