This paper presents feasibility studies of a multispectral moving target detection (MTD) system designed to detect and track low-signature moving targets. The system performs multispectral detection based on linear and nonlinear optimal discriminating features (ODF) for low-signature target detection and correlation tracking of slowly moving targets in clutter. Multispectral detection was tested against multispectral data from an acousto-optic tunable filter in the visible and near infrared. Optical Joint Transform Correlator for target tracking was designed and manufactured. The feasibility of correlation target tracking was demonstrated with actual Army MICOM FLIR long wavelength infrared (LWIR: 8 to 12 μm) images of moving vehicles and tanks in clutter.
This paper presents feasibility studies of a multispectral moving target detection (MTD) system designed to detect and track low-signature moving targets. The system performs multispectral detection based on linear and nonlinear maximum discrimination and representation features (MRDF) for low-signature target detection and correlation tracking of slowly moving targets in clutter. Multispectral detection was tested against multispectral data from an acousto-optic tunable filter in the visible and near IR. The feasibility of correlation target tracking was demonstrated with actual Army MICOM FLIR long wavelength IR images of moving vehicles and tanks in clutter.
This paper describes an Opto-Silicon Adaptive Imaging (OSAI) system capable of operating at low light intensities with high resolution, high accuracy, wide dynamic range, and high speed. The system consists of three major subsystems: (1) an adaptive imaging system in which a liquid crystal wavefront corrector measures image quality based on statistical analysis of a speckle field; (2) an image quality analyzer (IQA); (3) an opto-silicon multi-chip module combining a high-resolution ferroelectric liquid crystal SLM, CCD photodetector array, field-programmable gate array, and digital signal processor. The OSAI wavefront control applies adaptive optoelectronic feedback for iterative wavefront restoration and distortion compensation, suing an image quality metric based on statistical properties of the speckle field produced by moving a diffuser in the Fourier transform plane of a IQA optical system. A prototype IQA system was designed, manufactured, and tested using an input liquid crystal SLM, a Fourier lens, a light-shaping diffuser, and an output photodiode.
This paper describes all-optical packet header processing by content-addressable memory and optical joint transform correlation. The results of proof-of-principle computer simulation and experiment are presented.
This paper presents an eye tracking system that combines optical and electronic image processing for the precise measurement of eye movement parameters, including direction, speed, and acceleration. The system applies optical joint Fourier transform correlator and novelty filtering to measure the cross-correlation peak displacement caused by eye movements using magnified images of iris landmark patterns. This permits a 0.026 degree(s) accuracy of eye displacement measurements within a 6 degree(s) tracking range, or a 0.1 degree(s) accuracy within a 20 degree(s) range. Using digital micromirror device SLMs in the Fourier transform optical system, an inverse Fourier transform DSP module, and a high-speed digital camera, the eye tracking system will make it possible to detect and characterize saccadic intrusions in smooth pursuit eye movement.
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 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.
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 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.
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.
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.
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.
Processing of spatial and temporal optical flows with real time local correlation technique is described and discussed. Simulations and experiments with a time integrating acousto-optical correlator on real stereoimages are reported together with simulation on particle image velocimetry processing. Local correlation of 2D images done with an 1D correlator is here demonstrated by using projection in the 2D image.
A hybrid device which consists of a liquid crystal spatial light modulator (LC SLM) connected through fiber optics to a TV screen, being interfaced to a desk-top computer, is used for generating binary phase-only spatial filters (BPOFs) in a real-time TV/optical correlator. An adaptive optical/digital correlator with a BPOF and nonlinear feedback is described. The LC SLM phase-error correction is implemented using an iterative algorithm. The BPOFs with improved discrimination ability and circular harmonic BPOFs with spatial carrier are generated with the system.
The hybrid device which consists of a liquid crystal spatial light modulator connected through fiber optics to a TV screen, being interfaced to a desk-top computer, is used for generating binary phase-only spatial filters (BPOFs) in a real-time TV/optical correlator. An adaptive optical/digital correlator with a BPOF and nonlinear feedback is described.
A holographic associative memory in a feedforward network is implemented using photosensitive liquid crystal light valve (LCLV) as a phase conjugate mirror (PCM). In the case of three simple binary images stored in the Fourier hologram the completely reconstructed single output image (rectangle) is observed with only a quarter of the image present as an input. Because of non-zero cross correlation and high gain the restoration remains even if the input image is rotated by 25 degree(s) about the optical axis and is either tilted or swung horizontally by up to 45 degree(s). Parallel analog and digital optical computing operations are demonstrated by using an interferometric arrangement with a LCLV-based PCM. Image subtraction, coherent and incoherent image addition, OR, XOR, and NOT optical gates are achieved by controlling the phase difference between two spatially multiplexed signal-bearing waves.
An approach to hybrid optical/digital pattern recognition and scene analysis is described which uses a correlation procedure to compare the initial image (object, scene) with its rotated copy. The correlation function of object description obtained via this procedure is shown to possess scale and rotation invariance and to contain information about the object location in the scene being analyzed. The possibility of locating the objects and their classification using the correlation procedure is demonstrated by computer simulation and experiments performed in a coherent optical correlator with a liquid crystal light valve in the Fourier plane.
We consider some specific problems and phenomena of morphogenetic information storage, reproduction, and transfer including phantom leaf effect and field-induced morphogenetic translations between different taxonomic units. Several experimental results are presented and their explanation is given using a new approach to morphogenesis which combines some physical models of holographic associative memory and mathematical formalism of Fermi- Pasta-Ulam recurrence for solitary waves in deoxyribonucleic acid.
We consider some specific problems and phenomena of morphogenetic information storage, reproduction, and transfer including phantom leaf effect and field-induced morphogenetic translations between different taxonomic units. Several experimental results are presented and their explanation is given using a new approach to morphogenesis which combines some physical models of holographic associative memory and the mathematical formalism of Fermi- Pasta-Ulam recurrence for solitary waves in deoxyribonucleic acid.