Abstract: A programmable optical interconnection apparatus and method in which a plurality of spatial light modulators (SLM) form a plurality of spatially modulated beams from a data signal. A hologram is responsive to the spatially modulated beams for generating at least two destructively interfering coherent beams at a first optical detector to thereby disconnect the data signal therefrom, and for simultaneously generating at least two constructively interfering coherent beams at a second optical detector to thereby connect the data signal beam thereto. The hologram is preferably a computer generated thin hologram which does not rely on Bragg diffraction. A low cost, high density, high efficiency programmable optical interconnect is thereby provided.

Abstract: A dynamic holographic display has an array of reflective surfaces formed on cantilever structures substantially parallel to the surface of a substrate, such as a silicon wafer. A holographic image is formed by controlling electrical currents passed through the cantilever structures to position the reflective surfaces of the cells in the array so the topography forms a hologram, and reflected light interferes to form a holographic image. In a preferred embodiment, control is by computer and positions of reflective surfaces are determined by calculation from dimensional data available to the control computer.

Abstract: A fast, accurate system for manufacturing holographic projection screens. The invention (10) includes a mechanism (28) for moving holographic film (26) along a longitudinal axis thereof in a first direction. A mechanism (12) is provided for directing and maintaining an input beam (22) onto the film (26) as the film (26) is moved. The application of a reference beam (23) is then effective to create an interference pattern on the film (26) with the input beam (22). The mechanism (12) for maintaining the input image at a fixed location on the film includes a polygon shaped mirror mounted to rotate at a rate determined in accordance with the rate of movement of the film. An image stabilization system (40) is also provided which includes a detector (58) for monitoring an interference pattern created by the signal beam and the reference beam. Circuitry (60) is included for providing control signals in response to the detector (58) outputs. A phase shifter (44) induces a phase shift in the reference beam.

Abstract: An optical apparatus for simulating a highly interconnected neural network is disclosed as including a spatial light modulator (SLM), an inputting device, a laser, a detecting device, and a page-oriented holographic component. The inputting device applies input signals to the SLM. The holographic component optically interconnects N.sup.2 pixels defined on the spatial light modulator to N.sup.2 pixels defined on a detecting surface of the detecting device. The interconnections are made by N.sup.2 patterns of up to N.sup.2 interconnection weight encoded beams projected by N.sup.2 planar, or essentially two-dimensional, holograms arranged in a spatially localized array within the holographic component. The SLM modulates the encoded beams and directs them onto the detecting surface wherein a parameter of the beams is evaluated at each pixel thereof.

Abstract: A neural network processing element uses primarily optical components to model a biological neuron having both spatial and temporal dependence. The neural network processing element includes a switch-controlled laser source, a multiple holographic lens, a spatial/temporal light modulator, and a photodetector array. Laser beam control may be optical, electrical or acoustical, or a combination of these.

Abstract: Novel designs for efficient coupling mechanism for the conversion of typical profile laser beams into J.sub.o -profile beams are presented. Several specific embodiments are provided which employ non-linear optical mechanisms in the conversion process, and other embodiments are provided which utilize holography in the conversion process.

Abstract: An image enhanced optical correlator system providing for optical preprocessing of an input image prior to processing thereof in an optical correlator. The optical preprocessing is provided to enhance the image and/or image related characteristics such that the probability of detection of prescribed targets therein in the optical correlator is increased. In the system, an input image beam is split into orthogonally polarized image inputs, processed to enhance targets therein, and then the algebraic result (addition and/or subtraction) thereof is processed through an optical correlator. Techniques are used in the feedback systems to enhance the output plane correlation signal detection by an adjustment in phase, spatial frequency filtering and/or threshold setting optimization.

Abstract: A control arrangement for a galvanometer driven mirror whereby the angle of incidence of a beam on a holographic recording material is controlled includes a laser source and associated detector. The detector responds to a reflected position sensing beam incident thereon to generate electric currents. A ratio network forms the ratio of the sum and difference of the currents to generate an actual mirror position signal that is independent of the power output of the source of the sensing beam. An integrator is responsive to the error between the signal representative of the actual mirror position and a reference signal representative of a predetermined position of the mirror for forming a galvanometer position signal.

Abstract: A single material (not a multi-element structure) spatial light modulator (50) may be written to (30), as well as read out from (80), using light (20). The device has tailorable rise and hold times dependent on the composition and concentration of the molecular species used as the active components. The spatial resolution of this device is limited only by light diffraction as in volume holograms. The device may function as a two-dimensional mask (transmission or reflection) or as a three-dimensional volume holographic medium. This device, based on optically-induced electron transfer, is able to perform incoherent to coherent image conversion or wavelength conversion over a wide spectral range (ultraviolet, visible, or near-infrared regions).