Abstract: An imaging system is provided to minimize pixel defects by capturing an image in the spatial frequency domain. An image processor receives the spatial frequency-domain image data from the imager and transforms the frequency-domain image data into spatial-domain image data. To capture the image in the spatial frequency domain, an optical lens is placed between a spatial representation of an image object and the imager. The optical lens performs an approximate Fourier transform on light emanating from the spatial representation of the image object toward the imager. The image processor performs an approximate inverse Fourier transform on the data received from the imager, restoring the spatial representation of the image.

Abstract: An optical device for collecting light and selectively outputting or concentrating the light. A layer has an optical index of referaction n1l, and top, bottom and side surfaces defining an angel of inclination &phgr;. A back surface spans the top, bottom and side surface. A first layer is coupled to the bottom surface of the layer and has an index of refraction n2. The first layer index n2 causes light input through the back surface of the layer to be preferentially output into the first layer. A second layer is coupled to the bottom of the first layer and selectively causes output of light into ambient. Additional layers, such as alight polarization layer, a polarization converting layer and a post LCD diffuser layer can be used to make preferential use of polarized light of diffuse light having passed through the LCD layer to enhance viewing of the output light.

Abstract: An optical fiber communication system according to the present invention has, for example, first and second phase conjugators. The first phase conjugator converts a signal beam from a first optical fiber into a first phase conjugate beam. The first phase conjugate beam is supplied to the second phase conjugator by a second optical fiber. The second phase conjugator converts the first phase conjugate beam into a second phase conjugate beam. The second phase conjugate beam is transmitted by a third optical fiber. The second optical fiber is composed of a first portion located between the first phase conjugator and a system midpoint and a second portion located between the system midpoint and the second phase conjugator. The total dispersion of the first optical fiber substantially coincides with the total dispersion of the first portion, and the total dispersion of the second portion substantially coincides with the total dispersion of the third optical fiber.

Abstract: A multiplexing optical system capable of processing input information at high speed and with high accuracy and having an easy-to-align simplified arrangement. A parallel-beam generating device (11, 12, 13) generates an approximately parallel light beam. An input image display device has a grating member (222) which is latticed both vertically and horizontally, and a display device (22) which displays an input image. A Fourier transform lens (31) reproduces Fourier transformed images (311) of the input image by each order of diffracted light produced by reading the input image displayed on the display device (22) by the approximately parallel light beam from the parallel-beam generating device. The Fourier transformed images (311) are reproduced on a Fourier transform plane (F2) at an approximately constant pitch (p). A filter array (322) filters the reproduced Fourier transformed images (311). A lens array (33) performs an inverse Fourier transform on each filtered light beam.

Abstract: To effectively make a mesh of out lines between pixels by a pixel diffusion and at the same time to facilitate a focusing of an image by the observer, an optical filter for diffusing each pixel of a display device into a plurality of parts by utilizing diffraction or refraction is interposed between the display device having an image pattern in a mosaic form and an observer. The optical filter surface performs the pixel diffusion so that a sight angle, of a gap which does not pass light between the neighboring pixel after the pixel diffusion, as viewed from the observer on the focal plane on which the image displayed by the display device is observed by the predetermined observer is substantially a recognizable limit view angle of the observer.

Abstract: An apparatus for generating an independent coherent beam array from a single light source, in which individual coherent beams are selectively activated. The independent coherent beam array generating apparatus, which ensures high-efficient independent coherent beams from a single light source, are implemented by using a phase grating and a spacial light modulator. The number of multiple beams to be used as a light source for high-density recording and reading can be adjusted by varying the design of the phase grating. Regardless of the number of light sources required in various applications, once the beam array generating apparatus is adopted to the applications, the desired function of the applications can be implemented at low cost.

Abstract: Two pixel-oriented methods for designing Fourier transform holograms, pseudorandom encoding and minimum distance encoding when combined usually produce higher fidelity reconstructions than either method produces individually. In previous studies, minimum distance encoding was defined as the mapping from the desired complex value to the closest value produced by the modulator. This method is compared with a new minimum distance criterion in which the desired complex value is mapped to the closest value that can be realized by pseudorandom encoding. Simulations and experimental measurements using quantized phase and amplitude modulators show that the modified approach to blended encoding produces more faithful reconstructions than the previous method.

Abstract: Optical gratings having a range of possible Bragg wavelengths can be produced using a single phase mask by exposing the mask to a non-collimated spatially filtered beam of light. A spatial filter removes high spatial frequency components from the beam, and a focusing system directs the filtered beam to a phase mask. A rate at which the beam is focused and a spacing between the phase mask and a photo-sensitive waveguide are varied to produce gratings in the waveguide having a range of possible periods.

Abstract: A diffractive homogenizer is provided for receiving a beam of laser energy and producing a desired illumination pattern in a target plane. The homogenizer is made up of a plurality of diffractive sub-elements, each of which contributes to all or a portion of the desired image. By combining the contributions of many sub-elements to form the final image, a homogenizing effect is realized. In preferred embodiments, the sub-elements are designed to compensate for the finite spatial coherence of the incident laser beam and to control the numerical aperture distribution of the transmitted light. Each sub-element is composed of a large number of discrete pixels, each of which alters the phase of radiation passing therethrough by a selected amount. The pixel arrangement is chosen, using computer modeling and optimization techniques, such that the interference pattern created by the collective pixels in a sub-element makes up the desired image (or a portion thereof).

Abstract: An optical device for focusing a light beam. The device includes a Fourier diffractive element that can separate an incident beam into n beams along n directions which are symmetric about an optical axis. The device also includes a diffractive element including n Fresnel lenses capable of refocusing the n beams onto the optical axis. The device may be used with lasers and laser cutting devices.

Abstract: A first lens produces a Fourier transform of the wavefront distorted optical image at the Fourier transform plane. A phase encoded filter is positioned at the transform plane and a second filter is tandemly positioned with respect to the first filter, the second filter having a transmittance which is statistically similar to the reciprocal spatial frequency spectrum of the Fourier transform of the distortion function, to in turn produce an intermediate signal at the transform plane, which is now Fourier transformed by a second lens to recover the optical image having a substantially reduced degree of distortion.

Abstract: A method and system for imaging a small object in or behind a highly scattering medium comprises a laser source for illuminating the object with an ultrashort collimated beam of light and a novel microscope for forming a magnified image of the object using light emergent from the highly scattering medium, the emergent light consisting of a scattered component and a non-scattered component. The novel microscope comprises an objective, an eyepiece and an aperture centered at the back focal plane of the objective. The aperture, which may be of a fixed or variable size and controlled electronically or by a computer serves to spatially filter the scattered light component of the light emergent from the highly scattering medium. The system may also comprise a streak camera or similar time resolving device positioned at the image plane of the microscope for temporally filtering the scattered light component of the light emergent from the highly scattering medium.

Abstract: The present invention preferably includes a shading band which is suitably electro-optically created in a grid pattern formed through a photolithographic process, so consequently, the electro optic shading band is easily eliminated or re-configured dynamically to substantially eliminate its shading effect for lower density optical disks which do not experience substantial adjacent track crosstalk (ATC). Eliminating or reconfiguring the shading effect also helps in accommodating different media types and generations and those of different manufacturers. Moreover, the electro-optic shading band suitably adjusts the amplitude, phase, frequency, polarization and/or the like of the light beam to compensate for possible material property variations, defects, misalignments or other imperfections in the reading process. The present electro-optic shading band substantially restricts or alters any portion of a light beam containing signal information read from an optical disk.

Abstract: Collation Fourier image data (FIG. 1D) FB generated by performing the two-dimensional discrete Fourier transform (DFT) for the image data (FIG. 1C) of a collation pattern is synthesized with registration Fourier image data (FIG. 1B) generated by performing the two-dimensional DFT for the image data of a registration pattern. After amplitude suppression processing is performed for the resultant data, two-dimensional DFT is performed. A correlation peak is extracted from a correlation component area which appears in the synthesized Fourier image data (FIG. 1E) for which the two-dimensional DFT has been performed. A predetermined area including this correlation peak is then masked (FIG. 1F). The two-dimensional DFT is performed for the masked synthesized Fourier image data, and amplitude restoration processing is performed for the data. The resultant data is re-synthesized with the registration Fourier image data FA, and the two-dimensional IDFT is performed for the synthesized data.

Abstract: The invention comprises a spatial filter and a method of spatially filtering a laser beam, particularly a high power laser beam. The inventive spatial filter and method of use is especially suited for use in an optical system for writing index gratings in optical waveguides. The invention provides a method of writing gratings in optical waveguide fiber that results in improved grating performance.

Abstract: An adaptive structure of a Wiener filter is used to deconvolve three-dimensional wide-field microscope images for the purposes of improving spatial resolution and removing out-of-focus light. The filter is a three-dimensional kernel representing a finite-impulse-response (FIR) structure requiring on the order of one thousand (1000) taps or more to achieve an acceptable mean-square-error. Converging to a solution is done in the spatial-domain and therefore does not experience many of the problems of frequency-domain solutions. Alternatively, a three-dimensional kernel representing an infinite-impulse-response (IIR) structure may be employed. An IIR structure typically requires fewer taps to achieve the same or better performance, resulting in higher resolution images with less noise and faster computations.

Abstract: We disclose apparatus for holographic recording of information. The apparatus includes a lens or lens system, referred to here as the "FT lens," situated in such a way that light from an object beam enters the FT lens after passing through an object, and light leaving the FT lens impinges on a recording medium situated at a Fourier transform plane of the object with respect to the FT lens. In certain aspects of the invention, the apparatus includes a phase element effectively juxtaposed with the object, the phase element is effective for redistributing object-beam intensity in the Fourier transform plane, and the phase element has a correlation length greater than a maximum pixel side length associated with the object. In certain other aspects of the invention, the apparatus includes an optical element or optical system, referred to here as a "power optic," that adds convergence or divergence to the object beam before the object beam enters the FT lens.

Abstract: A method and apparatus for reading and decoding one-dimensional (1D) bar code symbols. A 1D bar code symbol is imaged by an optical assembly which includes a cubic phase mask that causes the optical transfer function of the optical assembly to remain approximately constant over a range of distances between the apparatus and the symbol to be read. An electrical representation of the resulting image is converted to a smoothly varying analog image signal. A transition identifying circuit processes the analog image signal, without first applying a recovery function that takes into account the effect of the phase mask, and generates a binary signal which is used to decode the symbol.

Abstract: A holographic grating is written into a photorefractive erasable holographic member and a light beam having a first wavelength which includes the joint power spectrum of a pair of joint images to be correlated is directed at the photorefractive member to partially erase the grating. A phase conjugate signal from the partially erased grating is then readout and Fourier transformed to produce the correlation output spots.

Abstract: Disclosed is a tunable multispectral optical apparatus for forming a spectrally processed image of a scene having finite angular extent or alternatively a point source of light, both of which may include multispectral components. A spatial filter is selectively positioned between a hybrid fore-optic and a hybrid reimaging optic, both of which include a diffractive optic. Spectral selectivity is obtained by proper positioning of the spatial filter relative to the intermediate image formed by the hybrid fore-optic before impinging on the hybrid reimaging optic. The tunable multispectral optical apparatus of the present invention may take the form of a bandpass filter or a bandstop filter depending only on the choice of spatial filter--blocking or passing selective wavelength components of the intermediate image.

Abstract: A grating modulator array (40) is comprised of a plurality of modulator sites (41). Each modulator site (41) is comprised of a plurality of first poled regions (50) and a plurality of second poled regions (51) alternating with said first poled regions. A first electrode (48a) is attached to a first end of each of the modulator sites and a second electrode (48b) is attached to a second end of each of the modulator sites and each of the electrode pairs establishes a field in the poled regions of the modulator sites which causes a phase shift in polarized light incident on the modulator.

Abstract: Low-cost complex plastic optics allow biocular viewing of video images generated by a single electro-optic display device, such as in a head-mounted display (HMD) for commercial or medical viewing applications. A dual off-axis configuration uses nearly collimated illumination optics and intermediate imaging optics to fill both eyepieces from a single display device without the need for a beamsplitter. Multiple illumination schemes are provided for either monochrome or color, and in either two-dimensional or time-sequential true stereographic presentation. Light from multicolor sources is superimposed, mixed, and homogenized by mixing light cones with diffractive collectors. Offsetting color overcorrection and undercorrection of individual optical elements achieves overall chromatic correction with minimal optical element complexity; A wireless video signal interface eliminates excess cabling.

Abstract: A constituent unit for an optical information processing system comprises an input information displaying device, which one-dimensionally, two-dimensionally, or three-dimensionally displays presented information as an optical pattern. Each of optical correlation operation devices located close to the input information displaying device detects only an optical pattern falling within a predetermined range among the optical pattern displayed on the input information displaying device, and carries out an optical correlation operation in order to calculate correlation between information representing the detected optical pattern and predetermined information having been stored in each optical correlation operation device. Each optical correlation operation device thereafter feeds out the results of the correlation operation.

Abstract: The invention is a pattern defect inspection system and method for improving the inspection speed, simplifying the system, and enlarging the inspection object, in which a correlation circuit (24) selects from a plurality of reference images in reference image storing means (22) one having the highest correlation with a detection image in detection image storing means (23) and inputs it to a difference circuit (25); the difference circuit (25) forms a difference image based on a reference image from the correlation circuit (24) and a detection image from the detection image storing means (23); a defect decision circuit (26) decides the position and size of a defect in a wafer under test 41, based on the difference image from the difference circuit (25); and the result is inputted to defect information processing means (27) to output as a defect information.

Abstract: The image quality of a hologram is evaluated by measuring the spacial distributions of luminance of an image reconstructed from the hologram and an object recorded thereon, normalizing the amplitudes of luminance per spacial frequency (which are obtained by Fourier transforms of the spacial distributions measured, respectively) and comparing the amplitudes normalized or obtaining a ratio between the amplitudes normalized.

Abstract: An improved method based on a simple imaging operation with a simple one-to-one mapping between resolution elements of a spatial phase modulator and resolution elements of the generated intensity pattern is provided.

Abstract: The laser transfer machining apparatus comprises a shaping unit for shaping the laser beam so that the laser beam has a beam pattern which corresponds to a desired pattern to be machined in the object to be machined and a generating unit disposed separately from the shaping unit for simultaneously generating a plurality of laser beams each having the beam pattern from the laser beam shaped by the shaping unit. The generating unit is adapted to emit the plural laser beams while simultaneously defining a plurality of radiation directions of the generated plural laser beams to the object to be machined. The laser transfer machining apparatus can provide a high efficiency of utilization of light and reduce the time required for machining. Furthermore, the laser transfer machining apparatus can utilize a laser with a relatively low spatially coherence such as an eximer laser.

Abstract: Low-cost complex plastic optics allow biocular viewing of video images generated by a single electro-optic display device, such as in a head-mounted display (HMD) for commercial or medical viewing applications. A dual off-axis configuration uses nearly collimated illumination optics and intermediate imaging optics to fill both eyepieces from a single display device without the need for a beamsplitter. Multiple illumination schemes are provided for either monochrome or color, and in either two-dimensional or time-sequential true stereographic presentation. Light from multicolor sources is superimposed, mixed, and homogenized by mixing light cones with diffractive collectors. Offsetting color overcorrection and undercorrection of individual optical elements achieves overall chromatic correction with minimal optical element complexity.

Abstract: The present invention is an improved material and method for use for providing diffuse transflectance of light. By employing an expanded polytetrafluoroethylene (PTFE) comprising a microstructure of polymeric nodes and fibrils, the material of the present invention demonstrates exceptional diffuse reflectivity and transmission of light across a wide spectrum of ultraviolet, visible, and infrared light. Additionally, the material of the present invention provides many properties that have been previously unavailable in highly diffuse transflective material, including a high degree of malleability, moldability and flexibility, and effective reflectivity even at relatively thin cross-sections.

Abstract: A superresolution scanning optical device has image forming means for forming the image of light from a coherent light source unit in the form of a fine spot on a conjugate face through an image forming optical system, and scanning means for scanning the fine spot formed on the conjugate face. The coherent light source unit has first and second light sources of which phases are reverse to each other. The first and second light sources have the relationship that the main lobe of the image of the second light source on the conjugate face is superposed on the lateral sides of the main lobe of the image of the first light source on the conjugate face.

Abstract: An optical system is provided with an adaptable window element at a Fourier plane for spatial filtering. Having a window element made up of individually addressable pixels provides a substantial improvement in the spatial filtering adaptability and precision. When combined with a computer and sensor, the window may become part of a negative feedback loop, thereby providing the optical system with more consistent reproducibility, higher reliability with graceful degradation, and more precise control over final results.

Abstract: An all optical photorefractive holographic joint transform correlator provides a first correlation plane output port using two-beam coupling, and a second correlation plane output port employing four-wave mixing. With appropriate input beam intensity ratios, the first port output is capable of high discrimination, while simultaneously the second port offers a low discrimination output.

Abstract: A module, capable of being mounted on a printed circuit board, containing optical components necessary for optical correlation and a unique folded light path technique for conversion from a Vander Lugt optical correlator to a joint-transform optical correlator, or visa versa, with no electronic changes required. The folded optical path permits a polarizing filter to be positioned in the beam path reflected by a filter SLM but before a correlation detector means when the correlator is in a Vander Lugt mode and permits the polarizing filter to be removed, and an auxilliary mirror or other optical components positioned in the beam path to eliminate the filter SLM and to direct the beam path toward the correlation detector means when the optical correlator is to become a two-cycle joint-transform optical correlator and simultaneously match the Fourier transform plane to the detector plane of the detector means.

Abstract: New on-axis, optically addressable spatial light modulators (SLMs) and methods of use are described. The new SLMs include a film of a photochromic material and a non-polarizing beam splitter arranged such that read and write beams counterpropagate with one another, and the read beam is separated from the path of the write beam after being transmitted through the photochromic material film without losing any polarization information encoded on the read beam. The new SLMs are advantageously implemented in incoherent-to-coherent optical converters and all-optical joint transform correlators.

Abstract: A method and apparatus maps a Gaussian beam into a beam with a uniform irradiance profile by exploiting the Fourier transform properties of lenses. A phase element imparts a design phase onto an input beam and the output optical field from a lens is then the Fourier transform of the input beam and the phase function from the phase element. The phase element is selected in accordance with a dimensionless parameter which is dependent upon the radius of the incoming beam, the desired spot shape, the focal length of the lens and the wavelength of the input beam. This dimensionless parameter can also be used to evaluate the quality of a system. In order to control the radius of the incoming beam, optics such as a telescope can be employed. The size of the target spot and the focal length can be altered by exchanging the transform lens, but the dimensionless parameter will remain the same. The quality of the system, and hence the value of the dimensionless parameter, can be altered by exchanging the phase element.

Abstract: The invention relates to systems and methods for optical Fourier processing and logic operations based on the discovery that the photoinduced anisotropy of photochromic materials such as bacteriorhodopsin, organic fulgides, azo and fluorescent dyes, phycobiliproteins, rhodopsins, and their analogs, is dependent on the intensity of a polarized actinic beam that illuminates the material and the intensity profile of one or more input beams. This intensity dependence can be used to implement a simple, real-time, self-adaptive optical processing, i.e., spatial filtering, system for Fourier processing of optical input images. This optical processing system can be used to process a wide variety of optical input images, from projected still images to live motion picture images.

Abstract: An advanced design for a phase plate enables the distribution of spots in arbitrarily shaped patterns with very high uniformity and with a continuously or near-continuously varying phase pattern. A continuous phase pattern eliminates large phase jumps typically expected in a grating that provides arbitrary shapes. Large phase jumps increase scattered light outside of the desired pattern, reduce efficiency and can make the grating difficult to manufacture. When manufacturing capabilities preclude producing a fully continuous grating, the present design can be easily adapted to minimize manufacturing errors and maintain high efficiencies. This continuous grating is significantly more efficient than previously described Dammann gratings, offers much more flexibility in generating spot patterns and is easier to manufacture and replicate than a multi-level phase grating.

Abstract: The polychromatic or monochromatic radiation beam emitted by a light source strikes an array of micro-filters which partially or totally transmit the light beam towards an array of micro-mirrors. The partially reflected beam comes back towards the first array of micro-filters and passes again through it until it reaches a viewer or a recording system or a screen. A relative movement between the two arrays of micro-filters and micro-mirrors enables static or animated images or colour strips selectable according to the needs to be generated.

Abstract: Apparatus and methods are disclosed for spatially routing an optical pulse (data pulse) of an electromagnetic radiation and containing a specific address temporal profile and possibly additional data. Routing generally involves a unit of active material that is programmed using one or more input beams or pulses of the electromagnetic radiation providing address (i.e., waveform-discriminating) and directional (i.e., pulse routing) information to the active material. During programming, a spatial-spectral grating is created by optical interference on or in the active material of the input pulses encoding the address and directional information pertinent to the data pulse.

Abstract: A projecting type image display apparatus includes a calculation processing unit for calculating a Fraunhofer diffraction image of an original image, an image display unit for producing/displaying the calculated Fraunhofer diffraction image, and an image converting unit for projecting the produced/displayed Fraunhofer diffraction image to the original image and projecting the original image on the screen. The calculation processing unit has a function of calculating the Fraunhofer diffraction image of the projection image and outputting the same to the image display unit. The image display unit is provided with an image display element on which the Fraunhofer diffraction image is optically displayed. The image projecting unit is provided with first and second lenses for converting the Fraunhofer diffraction image to the original image and projecting the original image on the screen.

Abstract: In a variable wavelength optical filter, a lens (3) is positioned at the output end of a first optical fiber (1) and transforms an input optical signal to parallel light. A dielectric interference optical filter (8) is located at the rear of the lens (3) in order to transmit only the light of particular wavelength. A lens (4) converges the light output from the filter (8) into the input end of a second optical fiber (2). A rotary plate (7) is affixed to the output shaft (6) of a servo motor (5) whose rotation angle is controlled by an electric signal fed from the outside of the filter. The filter (8) is mounted on the rotary plate (7) with the intermediary of a piezoelectric element or elements (9). The piezoelectric elements (9) are caused to oscillate by a modulating signal, so that the transmission center wavelength of the filter is varied. The resulting deviation of the transmission center frequency is detected.

Abstract: A system for creating a bright and uniform line of illumination. The "hot spot" of an arc lamp is imaged onto a narrow, circular pinhole aperture. Light passing through the pinhole aperture is collimated and passed through a second aperture (the apodizing aperture), before being focused to a line of illumination by a cylindrical lens. The spatial profile of the apodizing aperture is tailored to remove non-uniformities in the illumination source thereby allowing a highly uniform line of illumination to be created. Alternatively, the spatial profile of the apodizing aperture can be tailored to produce a line of illumination having a desired non-uniform intensity profile.

Abstract: A Fourier mask includes a base plate, an aperture plate having a pair of cross hairs fixedly mounded on the base plate and a pair of four bar linkages, each four bar linkage being made up of a pair of parallel cross bars and a pair of parallel mask bars pivotally interconnected end-to-end in a closed loop configuration. Each cross bar in each four bar linkage is pivotally mounted on the base plate, the four bar linkages being arranged on the base plate such that the mask bars in one four bar linkage are at right angles to the mask bar in the other four bar linkage and each pair of parallel mask bars is symmetrically disposed about one of the cross hairs. By pivotally moving either or both sets of cross bars on the base plate, the spacing between the parallel mask bars in either a both sets of mask bars can be changed as desired.

Abstract: An artificial retina cell effectively used to recognize a plurality of objects from an image containing them with ease and at high speed. Also disclosed are an artificial retina and an artificial visual apparatus employing the same. The artificial visual apparatus includes an artificial eyeball (3) having a focusing means (2) and an artificial retina (1) including a first artificial retina cell disposed in a central visual field (1a) to detect a bright-dark boundary by optical filtering and a second artificial retina cell disposed in a peripheral visual field (1b) to detect an object position by optical filtering, and a neural network (4) for executing pattern recognition of an object on the basis of information detected by the first artificial retina cell.

Abstract: A method and apparatus for implementation of neural networks for face recognition is presented. A nonlinear filter or a nonlinear joint transform correlator (JTC) employs a supervised perceptron learning algorithm in a two-layer neural network for real-time face recognition. The nonlinear filter is generally implemented electronically, while the nonlinear joint transform correlator is generally implemented optically. The system implements perception learning to train with a sequence of facial images and then classifies a distorted input image in real-time. Computer simulations and optical experimental results show that the system can identify the input with the probability of error less than 3%. By using time multiplexing of the input image under investigation, that is, using more than one input image, the probability of error for classification can be reduced to zero.

Abstract: A method and device for shaping both the temporal and spatial profiles of an input optical pulse to generate an output optical waveform are described. The method includes the step of dispersing the spectral frequencies of the input pulse. These frequencies are then focused with a cylindrical lens to form a two-dimensional optical field. The field is imaged on a mask featuring a two-dimensional array of pixels. The amplitudes, phases, or phases and amplitudes of the two-dimensional optical field are then filtered with the mask. The filtered spectral frequencies are then recombined to form the collective temporal profile of the output waveform. The two-dimensional optical field is then imaged in a sample plane to form the spatially coherent regions.

Abstract: A optical processor facilitates the alignment between an original image and transformation patterns, thus improving the operation accuracy, and, if a fixed transmission mask is to be used, facilitates the fabrication of the fixed transmission mask. The optical processor includes an original image display to display an original image and a pattern display to display the patterns for a transformation on the original image displayed on the original image display. In the optical processor, the original image display is os made as to have pixels with a smaller aperture ratio than that of the pixels of the pattern display.

Abstract: An optical image processor includes a nonlinear active gain medium for recording an interference pattern that corresponds to the Fourier transform of an input image or the multiplicative product of the Fourier transforms of two respective input images.

Abstract: An apparatus and method are disclosed for providing holographic matched filters for application in all-optical holographic processing of ultrahigh-speed optical data. A scaled spatial image of temporal-domain data is provided by a spatial light modulator (SLM). The scaled image of the SLM is read out with a single-mode diode laser and transformed into a wavelength spectrum by a Fourier transform lens. The interference fringe patterns between the spectrum of the scaled spatial data pattern and the reference pattern beam are recorded by a holographic recording medium. Alternatively, the scaled spatial image of the temporal data is fixed in an aperture mask. An apparatus and method are also disclosed for decoding high-speed optical signal packet headers using holographic matched filters.

Abstract: The present invention discloses a device for and method of simulating an image in real time under turbulent atmospheric conditions. The present invention is realized by expanding a first laser beam using a microscope-objective and a first lens. The expanded light is then projected onto a first LCLV. Light reflecting from the first LCLV is filtered, focused onto a diaphram, polarized, and directed along a path that is around two meters in length. The light is then split into a first beam and a second beam. The first beam is focused onto an optical fiber bundle which is connected to the first LCLV. One end of the optical fiber bundle is rotated with respect to the other end. The second beam is projected upon a second LCLV. A second laser beam is expanded and projected onto a LCTV. The image is provided to the LCTV. The LCTV image is projected onto, and modulated by the second LCLV.