Abstract: A device for providing illumination to a specifically defined region including in combination an extended and diffuse light source and a holographic optical element mounted in spaced relation to said light source, said holographic optical element comprising a layer of holograph adaptable material having formed thereon an array of independent holographic lenses each responsive to selected regions on said light source for directing light collected from said selected regions on said light source to a selected viewing pattern.

Abstract: Method and display for providing a magnified image of a two-dimensional, periodic image pattern. An apertured sheet is arranged in front of the two-dimensional, periodic image pattern preferably being in a plane B and preferably in distance therefrom, the apertured sheet preferably also being in a plane A and in any direction to the plane having a center distance between the apertures, which almost corresponds to the center distance in the same direction in the plane B containing the periodic image pattern. As a result, a magnified image of the individual image element of the image pattern is obtained. Moreover, a stereoscopic depth effect may be obtained, if the apertured sheet and the image pattern are in different planes.

Abstract: A holographic optical filter separates broadband electromagnetic radiation into spectral components corresponding to different spectral regions and then images this radiation onto pixels of a display. It includes two layers of holographic optical elements that are sensitive to each of these spectral regions. The holographic optical elements generally transmit radiation outside of their bandpass but can diffract radiation falling within it. The filter is well suited for display applications and can be used in either a reflective or transmissive mode.

Abstract: An illumination system for an image transfer system having a gate at which an original image to be transferred can be positioned, to provide a transfer region of illumination at the gate, comprising:(a) a light source;(b) an optical assembly positioned to receive light from the light source and direct and shape the light to form a first region of illumination, the optical assembly including at least one integrator assembly which provides improved spatial uniformity of the light without diffusing the light;(c) a diffuser in the path of light from the optical assembly to increase optical divergence of the first region of illumination to form the transfer region of illumination.

Abstract: A confocal optical apparatus comprising a light source, a first aperture portion for passing light emitted from the light source and obtaining a point source, an objective lens for causing the light that has passed through the first aperture portion to converge on a measurement object, a second aperture portion located on a plane conjugate with the convergence surface on the measurement object, and light detectors for detecting light that has passed through the second aperture portion, wherein placing the first and second aperture portions in the same position and using them as the same aperture portion, as well as positioning the detection surfaces of the light detectors substantially on the same surfaces as the conjointly used identical aperture portions make it possible to reduce the size and weight of the apparatus, to perform three-dimensional shape measurements rapidly and accurately, and to facilitate the alignment of each portion.

Abstract: Optical systems are disclosed which are capable of generating and rapidly changing time delays of electrical signals for true time delay beam formation and beam steering and for signal processing applications. The systems utilize an interferometer configuration. A first optical modulator in a first leg of the interferometer is used to modulate coherent light with the signal to be delayed. In a second leg of the interferometer, a second optical modulator provides beam steering to a prism stack, which produces a set of plane reference waves having a range of orientations required to generate a desired range of time delays. Preferably the optical modulators are acousto optic Bragg cells. Alternatively, a stack of lens pairs or diffractive optical elements or a holographic optic element may be used in place of the prism stack. The modulated optical signal from the first leg interferes on an array of photodiodes with the reference waves from the second leg.

Abstract: A beam homogenizer for converting an incident beam of non-uniform spatial power or energy distribution into an output beam of uniform spatial power or energy distribution. The homogenizer is a holographic optical element constructed from an array of facets or subholograms and positioned at a first plane in the path of an incident signal. The transmittance from each subhologram is uniformly spread across a target at a second plane that is spaced away from the first plane Another optical element, such as a holographic collimation element, may be placed at the second plane to collimate the transmittances thereupon.

Abstract: The present invention is a holographic structured light generator (HSLG) for generating an array of an arbitrary number of laser beamlets from a single laser beam using a point laser light source and a hologram. In a first preferred embodiment of the present invention, a hologram having an image of four point sources in a common plane is fabricated using four point sources as the object beam, and a reference beam. A reconstruction beam, aligned identically with respect to the hologram as was the reference beam during fabrication of the hologram, is then directed at the hologram, generating the array of laser beamlets from the four point sources in the hologram. In a primary application of the HSLG, it is used to map the surface of an object in three dimensions. The HSLG is used with video cameras, computer image processing equipment and an optical spatial light modulator to yield 3-D data for use with CAD systems.

Abstract: A method and system for fabricating a multiple holographic element. The method comprises the steps of forming a master multiple holographic element having an absorption grating pattern that produces a given index of refraction pattern across the master multiple holographic element, coating the master holographic element with a layer of a photopolymer, and directing a recording beam to and through the master holographic element and into the photopolymer layer. The absorption grating pattern of the master holographic element modulates the amplitude of the recording beam, and the modulated recording beam causes the monomers of the photopolymer to form a monomer pattern that produces the given index of refraction pattern across the photopolymer layer. The method further comprises the steps of fixing the monomers of the photopolymer layer in that monomer pattern to form thereby a copy of the multiple holographic element, and removing the photopolymer layer from the master holographic element.

Abstract: Sensitometers are used for monitoring photographic and radiographic processes, and then making it possible to control these processes. However, although it is relatively straightforward to obtain control strips for individual sensitometers, it is often difficult to compare the results of control strips which have been exposed using different sensitometers. Described herein is a method for calibrating or cross-referencing sensitometers. The method comprises exposing a first control strip to a step wedge in the first sensitometer, and a second control strip-to a step wedge in the second sensitometer, the first and second control strips being formed on the same photographic material. The material is then processed and the characteristics of the material is determined using the known exposures given to the material by the second sensitometer and the density values obtained corresponding to those exposures.

Abstract: An optical memory is disclosed in which data is stored in an optical data layer capable of selectively altering light such as by changeable transmissivity or polarization. The data is illuminated by controllable light sources and an array of multi-surface imaging lenslets project the image onto a common array of light sensors. Data is organized into a plurality of regions or patches (called pages) in which each page contains a field of data spots that encode multiple states or levels of data by the amount of transmissivity or polarization of that spot. By selective illumination of each data page, one of the lenslets images the selected data page onto the light sensors. Light in the data image pattern strikes different ones of the arrayed light sensors, thereby outputting the multiple levels per spot in the form of electrical data signals that are A/D converted to digital.

Abstract: A hologram structure for use in a holographic center high mounted stoplight system for a vehicle. The hologram structure includes first and second hologram layers laminarly secured to each other, each having a plurality of bright hologram cells and dim hologram cells formed therein, and each hologram cell being configured to diffract light into a predetermined solid angular region. The bright hologram cells and the dim hologram cells of each hologram are arranged in a pattern to produce a recognizable pattern of bright and dim areas.

Abstract: Optical systems are disclosed which are capable of generating and rapidly changing time delays of electrical signals for true time delay beam formation and beam steering and for signal processing applications. The systems utilize an interferometer configuration. A first optical modulator in a first leg of the interferometer is used to modulate coherent light with the signal to be delayed. In a second leg of the interferometer, a second optical modulator provides beam steering to a prism stack, which produces a set of plane reference waves having a range of orientations required to generate a desired range of time delays. Preferably the optical modulators are acousto optic Bragg cells. Alternatively, a stack of lens pairs or diffractive optical elements or a holographic optic element may be used in place of the prism stack. The modulated optical signal from the first leg interferes on an array of photodiodes with the reference waves from the second leg.

Abstract: A hologram structure for use in a holographic center high mounted stoplight system for a vehicle. The hologram structure includes a hologram layer having a plurality of holographic lenses formed therein, each holographic lens being configured to diffract light into a predetermined solid angular region.

Abstract: Amplification and synchronization of photon pulses in optical computing chips is accomplished by placing parametric amplifying devices at predetermined spatial locations in the light conductive paths that make up the optical circuits in the chip. The laser pumping signal for the parametric amplifiers is clocked by a system clock which also clocks the generation of the data photon pulses in the optical circuits. By synchronizing the arrival of a pumping pulse with the arrival of the photon pulse at a parametric amplifier, the data pulse can be amplified, reshaped and resynchronized. The pumping pulse can be directed to the spatially located parametric amplifiers on the chip in a number of different ways. The chip could be masked except for the parametric amplifiers, and the entire chip could be illuminated by the pumping laser though collimating lens. If the chip is not masked, then pumping light must be directed only to the parametric amplifiers.

Abstract: A hologram structure for use in a holographic center high mounted stoplight system for a vehicle. The hologram structure includes a hologram layer having a plurality of single grating holograms formed in therein, each single grating hologram configured to diffract light at a respective predetermined angle.

Abstract: This invention relates to the fabrication of lenses which can focus a light beam to a spot size which is smaller than that allowed by diffraction theory. A composite lens function is constructed using a strong centered lens function and several additional lens functions having different weights, different separation distances from the center, and different phases. The focused spot consists of the vector sum of these differently weighted electric fields from the separate lens functions. By varying the separation distances, the weights, and the phases of the additional lens functions, the vector sum of the electric fields from the lens functions produces a focused spot whose width is less than the diffracted limited spot size. Such composite lens functions can be produced, for example, using diffractive optics techniques or by programming the lens function onto a spatial light modulator.

Abstract: The present invention discloses a novel method for effecting illumination of an arbitrary aperture. The method comprises a first step of providing a developed hologram comprising a plurality of spatially known discrete holographic optical elements that have been generated from a common arbitrary aperture. A second step comprises directing a plurality of dedicated reconstructing beams to assigned ones of the holographic optical elements, so that a composite hologram beam illuminates the arbitrary aperture.

Abstract: A star tracker for generating positional information for a vehicle includes a holographic telescope (150) having one or more fields of view for imaging stellar objects. The telescope includes a plurality of radiation detectors (100) and an input aperture comprised of a primary holographic optical element (HOE) (134). The primary HOE provides one or more wavefronts to one or more secondary HOEs (136), each of which applies a chromatic correction so as to correct for a chromatic aberration induced by the primary HOE. A single or multiple field of view Schmidt telescope embodiment is also disclosed having one or more aspheric corrector plate HOEs and one or more associated concave spherical reflectors.

Abstract: The lens includes a plurality of lenslets arranged substantially contiguously in an array. Each lenslet is adapted to receive radiation from a particular zone not substantially overlapping with adjacent zones, and to focus said radiation to a predetermined common point. A detector may be located adjacent said common point and preferably includes at least two detector elements each to detect infra red radiation from a different zone.

Abstract: This is an optical interconnect system. The system comprises: at least one signal transmitter; at least two signal receivers; at least one DMD in the same plane as the signal transmitter; and a hologram, whereby the phase of the original beam from the signal transmitter may be programmably changed, by a DMD, such that the beams received at the signal receiver may cancel or reinforce. Other methods and devices are disclosed.

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: The disclosed thyristor comprises an n.sup.- semi-conductor layer, a p.sup.- semiconductor layer disposed on one surface of the n.sup.- layer to form a pn junction between them, an n.sup.+ and a p.sup.+ semiconductor layer disposed on the other surfaces of the n.sup.- and p.sup.- layers respectively to serve as main electrodes and a p.sup.+ and a n.sup.+ apertured gate layers disposed within the n.sup.- and p.sup.- layers respectively and provided with a gate electrode. An intrinsic semiconductor layer may be substituted for the n.sup.- and p.sup.- layers. A process of producing such a thyristor is also disclosed.