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This paper describes the development of real-time non-contact metrology based on holographic interferometry and neural network fringe analysis software to detect defects in composite materials. The object under inspection is illuminated by a high-power solid-state laser, and the light scattered from the material surface is recorded in real time using a double-exposure holographic interferometer, which can detect minute surface deformation caused by defects in the material. Thermal stimulation of the object creates a non- uniform time-varying material reaction, which causes surface deformation that is characteristic of the material's internal structure. This deformation in turn creates time-varying interference patterns, which are recorded by a real-time holographic interferometric system and displayed on the computer monitor through a CCD camera. The system allows real- time, in-depth non-contact inspection of composite materials used in aircraft and other military vehicles. A genetic algorithm has also been developed for fast data processing in a non-laboratory environment. The sophisticated neural network recognizes the types of defects at high speed.

In this paper a new algorithmic and hardware approach to real-time processing, computing, compression and transmission of multi-media (video, imagery, audio, sensor, telemetry, computer data) information, in the form of synchronized data, was proposed. The proposed approach, called Soft Computing and Soft Communication, leads to multi-media throughput minimization and data homogenization.

Physical Optics Corporation has developed an advanced 3-D virtual reality system for use with simulation tools for training technical and military personnel. This system avoids such drawbacks of other virtual reality (VR) systems as eye fatigue, headaches, and alignment for each viewer, all of which are due to the need to wear special VR goggles. The new system is based on direct viewing of an interactive environment. This innovative holographic multiplexed screen technology makes it unnecessary for the viewer to wear special goggles.

Physical Optics Corporation has developed a unique technology and processes to fabricate a 3D display system that does not require wearing glasses or other eyewear. The authors present the result of true 3D (T3D) monitor development, the third generation T3D being based on a holographic multiplexing screen. The monitor displays 3D autostereoscopic information to three viewers. Holographic multiplexing allows a large number of viewers to see the 3D effect without compromising resolution or having to wear any type of special glasses or goggles. The 3D monitor can deliver high resolution graphics -- 1024 X 480 pixels -- as well as NTSC video in both composite and S-video formats.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Holographic recording techniques have been applied to implement synthetic estimation filters (SEF) for pose estimation of a docking spacecraft. Each SEF is a weighted combination of Fourier-plane hologram exposures of different target attitudes. These particular attitudes represent a span of the attitudes among which the SEFs will ratiometrically interpolate the attitude of the target in an input image. The pose is estimated by comparing the correlation peak intensities for all the filters with previously stored reference intensity peaks.

An optical communication/switching system with data speeds well beyond any state-of-the-art electronic board-to-board computer interconnect is proposed. This interconnect is based on the use of microprism arrays to achieve large-scale, wideband interconnections for optoelectronic systems.

Fractal image processing technology has been recognized as having great potential in automatic target recognition (ATR) and image compression. In this paper, Physical Optics Corporation demonstrates the feasibility of using a fractal image processing technique as a new and efficient approach for signature, pattern, and object recognition. Using optical Fourier transform and a ring-wedge detection technique, we generate and measure the power spectral density of an input scene. The log-log plot of the power spectral density vs. spatial frequency provides a very valuable signature for each input. Experimental results show that we can successfully discriminate man-made objects from natural objects in input scenes by analyzing signatures obtained this way.

An all-optical reconfigurable crossbar switch is implemented by unique integration of dynamic photopolymer technology, simple geometry optics, and waveguide technology. This all-optical crossbar switch provides high reconfigurability, large fanout, and radiation hardening. These characteristics are essential for both parallel/distributed processing and high-bandwidth communication, especially for B-ISDN.

The search for a dynamic recording medium that can be used in real time without the need for processing has become a critical issue in the development of practical neural network systems, correlators, all-optic switches, image and signal processors, and optical storage devices. A typical optical material respond to changes in the intensity, polarization, or wavelength of the illuminating light. The optical material developed and used for neural network applications responds to changes in the polarization of blur or green laser light. Implementing a neural network or performing optically-controlled acoustic beam steering requires a high-speed read/write/erase optical memory. POCs erasable dye polymer material offers a high read/write/erase data rate, nondestructive reading, fast data access, high storage density, overwrite capability, and long cycle life.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Optical interconnects have been designed, fabricated, and tested, and a graphics processor based on field-programmable gate arrays has been designed. The board-to-board connection approach is based on multi-channel integrated optical waveguides with novel optoelectronic active connectors, allowing multiple simultaneous data transfers among many boards. Data is transferred from chip to chip through optical data channels within an integrated chip. For electronic processing systems, we developed a preliminary design for a multiprocessor system suitable for both single instruction multiple data and multiple instruction multiple data, and using video random access memory and static random access memory for main memory, look-up table processing, and display interface.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Genetic algorithm performance has been improved by adaptively modifying genetic operators, and by filtering out recurring chromosomes from the fitness evaluation process. The enhanced genetic algorithm has been applied to neural network topology selection and function optimization. The performance of the algorithm was evaluated in multiple function and problem domains, where it showed superior convergence speed.

In this presentation, a fuzzy logic adaptive genetic algorithm (FLAGA) software engine is applied to hypercompression pre- processing. The FLAGA has a genetic algorithm (GA)-engine, tunable by fuzzy-logic rules. As a result, basic GA-engine operations, such as spanning, crossover, and mutation, have tunable rates, according to progress in the convergence process. Since the rates of these operations are not fixed but optimized in real-time, FLAGA convergence speed is at least one-order-of-magnitude higher than equivalent speed for a standard GA. In this paper, we present theoretical analysis and simulation results for this specific fuzzy logic application, as well as further considerations related to the application of FLAGA to video imaging and edge-extraction ATR (automatic target recognition).© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Artificial neural networks have proven to be powerful tools for sensor fusion, but they are not adaptable to sensor failure in a sensor suite. Physical Optics Corporation (POC) presents a new sensor fusion algorithm, applying fuzzy logic to give a neural network real-time adaptability to compensate for faulty sensors. Identifying data that originates from malfunctioning sensors, and excluding it from sensor fusion, allows the fuzzy neural network to achieve better results. A fuzzy logic-based functionality evaluator detects malfunctioning sensors in real time. A separate neural network is trained for each potential sensor failure situation. Since the number of possible sensor failure situations is large, the large number of neural networks is then fuzzified into a small number of fuzzy neural networks. Experimental results show the feasibility of the proposed approach -- the system correctly recognized airplane models in a computer simulation.

Optoelectronic SAR signal processing for real-time parallel adaptive on-board wide area surveillance and ATR applications is described. The signal processing architecture consists of a coarse ATR processor that performs early detection of small targets to select regions of interest in a large field of view, and a fine ATR processor for accurate classification of selected targets. Both coarse and fine ATR processors apply circular correlation-based algorithms implemented with optical joint transform correlators. Together with associative memory and genetic algorithm composite filtering, this discriminates among similar targets and rejects cluttered backgrounds.

Physical Optics Corporation has developed an autostereoscopic 3D display system that does not require viewers to wear goggles. This system is based on a stationary holographic projection diffuser fabricated using volume multiphase holographic optical elements. Design and development of the prototype are also described.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We describe here a holographic non-destructive inspection (NDI) technology developed by Physical Optics Corporation. It is based on real-time holographic dye polymer materials and a shearographic camera, with neural network defect classification software. Holograms can be recorded in or erased from the new dye polymer material in a millisecond without wet processing, making real-time holographic NDI feasible. The shearographic NDI system, based on laser speckle interferometry, compensates for low-light conditions. Both holographic and shearographic fringes are input to the neural network system to perform automatic defect type classification.

Optical interconnects will play an increasingly significant role in future space applications, because of their high transmission bandwidth potential and radiation hardness. This paper presents the development results of a hybrid optoelectronic system comprising four electronic processing boards that communicate through an optical 3 by 3 non- blocking crossbar switch. Each processing board contains Tx and Rx modules pigtailed to multimode fibers. An optical fan-out of 1-to-3 is implemented by means of a holographic grating. The fan-in is implemented as a lens array. The system has been tested using dedicated automatic target recognition (ATR) software, and space testing is planned.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A novel all-optic waveguide crossbar switch based on an in-house developed birefringent material is presented here. This switch uses visible light ((lambda) equals 514 nm) for programmable beam addressing to provide all-optic reconfiguration in both single-mode and multi-mode waveguides. An array of waveguide beams can be addressed within milliseconds using very moderate optical pumping powers (below 100 (mu) W). This allows green emitting diodes to be used for signal switching. The switch is characterized by high speed, high switching sensitivity, low waveguide loss, low optical noise levels, erasability, and reasonable cost.

A new fractal dimensionality measurement and analysis-based automatic target recognition (ATR) is presented. ATR is a multi-step procedure, such as preprocessing, interest locating, segmenting, feature extracting, and classifying. Physical Optics Corporation has developed a new ATR system, based on fractal image processing, which can perform interest locating, segmenting and feature extraction simultaneously. Experimental results of the proof-of- principle is also presented.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A new automatic target recognition (ATR) technique called fractal transform is presented. The fractal transform is a combination of fractal image processing and the Hough transform. A measurement of the power spectral density (PSD) of an input scene was performed using a ring-wedge detector to obtain a log (PSP) vs. log (spatial frequency) plot. By analyzing the log-log plot by the Hough transform and a neural network, the ATR operation based on fractal transform is achieved.

A highly functional and versatile camera platform for a multi-purpose robotic vehicle utilizing a novel modular approach is presented. The platform uses only three CCD camera, four computer-controlled rotation stages and three modular optical imaging systems to provide both a stereo vision mode at any desired viewing angle and a panoramic vision mode with a 180° nonoverlapping field-of-view. The panoramic view from the imaging system of each module is collected by one of three mirrors and transmitted collectively towards a corrresponding CCD camera. Stereo vision mode is accessed by aligning any two of the three modules in parallel using their respective rotation stages. When the entire assembly is rotated by another rotation stsge, any desired viewing angle is obtained.

A new scheme for digital optical computing, utilizing a non-holographic opto-electronic addressable memory (CAM), is discussed. To illustrate the performance of this arithmetic processor, the design of an optical binary carry look-ahead adder (CLA), also, the design of a binary, a logarithmic number (LN) and a residue number (RN) multipliers are presented. Compared to existing opto-electronic approaches, this non-holographic CAM offers a number of practical advantages, such as fast processing speed, ease of optical implementation and alignment. Two spatial input data encoding techniques, an active low and high, are discussed. A multioperation multibit CAM processor is presented. Experimental results for a CLA adders; and a binary, residue and logarithmic number multipliers are also presented.

Optical temporal pyramidal image processing based on liquid-crystal televisions (LCTVs) and noncoherent illumination is proposed. compact non-coherent optical tracking novelty filter and its use as a temporal pyramidal filter are demonstrated. Some preliminary experimental results are presented.

Pyramidal processing is a form of multiresolution image analysis in which a primary image is decomposed into a set of different resolution image copies. Pyramidal processing aims to extract and interpret significant features of an image appearing at different resolutions. Digital pyramidal image processing, because of the large number of convolution type operations, is time-consuming. On the other hand, optical pyramidal processors, because of their ease in performing convolution operation, are preferable in real-time image understanding applications. Two methods of optical pyramidal image generation, a Fourier spectrum filtering based, and a local averaging using 2D lens array, are presented. Preliminary experimental results for optical Gaussian, Laplacian and other fivadtree pyramidal image processing are shown. Experimental results, using commercial lifiuid crystal TVs, for a real-time pyramid image generation are presented.