Abstract: An encoding scheme, in readout, generates a spatially separated entire spectrum for each one of the three primary colors. This permits spatially separated color filters to select each primary color from its own spectrum.

Abstract: Two substantially identically patterned transparencies, i.e. a master photomask and a copy thereof, are compared with each other by transluminating the master with an object beam, producing a hologram of that master by letting the object beam interfere with a reference beam from a common source of coherent light such as a laser, placing the copy in the path of the object beam formerly occupied by the master, and positioning the developed hologram at the intersection of the two beams to generate a compound beam of zero intensity if the two transparencies are identical. The luminous energy of the compound beam thus varies inversely with the degree of equivalency of the two transparencies. The compound beam may be imaged onto a receiving surface, with certain areas thereof blocked out to eliminate error indications from insignificant (e.g. marginal) zones.

Abstract: Method and apparatus for obtaining the doppler transform of a one-dimensional linear signal by re-arranging the signal into a two-dimensional raster form image pattern and then obtaining an optical linear transformation of the two-dimensional image. An optical circuit is provided for carrying out the transformation and is designed to process the signal for a large number of doppler levels in rapid succession without it being necessary to rescan the initial signal each time as in the prior art. Accordingly, a substantial reduction in processing time is achieved.The invention has been developed primarily for use in locating the position of underwater objects through the use of sonar, but has application in a variety of other data processing fields.

Abstract: A reflector or mirror for the visible and rear infrared spectrum is formed by multicoating copper with one-fifth wavelength and three-quarter wavelength films. These films are alternating low and high index films, and MgF.sub.2 and TiO.sub.2 are presently preferred. A thin bonding layer of TiO.sub.2 is used to secure adhesion of the MgF.sub.2 to the copper. This coating enhances the reflectance in the visible range without appreciable degradation of reflectance in the near infrared, so that the resultant curve of reflectance-versus-frequency is substantially flat. The resulting coating is hard and tough and may be cleaned without injury and withstands high humidity.

Abstract: The present invention related to optical collimating systems and has particular reference to beam compression of laser diode emission.

Abstract: A method of constructing cross-section images similar to "computer assisted tomography," using optical data processing to replace the computer. The method uses incoherent light in the optical processor, thereby avoiding the noise and diffraction patterns inherent in images processed with coherent light. The method disclosed in this invention allows the processing to be carried out in real-time as the data are being collected.

Abstract: A jewel and method of making same, the jewel being a unique hologram and lens combination. A reflection hologram of an object is first made and the psuedoscopic image is then used in recording a second generation hologram which permits reconstruction of the virtual image near or within the lens upon which the second generation hologram is located, usually being adhered thereto, the lens functioning to refract incident white light and enhancing spectral changes and brightness, while virtually eliminating the critical angle effect in the viewing of the jewel, and dramatically increasing the optical leverage or proportional magnification of apparent movement of the image for any given alteration in the incident light or viewing angle relative to the jewel.

Abstract: In a coherent optical correlation system for detection of object images at unknown angular orientations, a holographic spatial filter in the transform plane of the system is rotated until a correlation beam is produced. The spatial filter is mounted on a rotating cylinder which carries a first mirror placed in the path of the correlation beam emitted from the filter and disposed to direct the beam toward the axis of rotation of the cylinder and a second mirror on the axis and intercepting the beam for directing the correlation beam substantially along the axis. A motor drives the cylinder about its axis and an optical encoding device associated with the rotating cylinder provides an electronic indication of the cylinder orientation at any given instant.

Abstract: A method and apparatus to optically control mass produced articles by a holographic correlator. The articles are continuously moved through an input beam of the holographic correlator. The correlator employs a holographic filter having a plurality of Fourier spectra recorded thereon, which are spatially separated but overlapping and which correspond to different orientations of the reference specimen. During the translation of the object through the input beam, the beam is reflected so that all spectra are addressed through the holographic filter. The output correlation spot is detected through a diaphragm having a slit-form aperture. This apparatus and the method it employs does not depend on the orientation between the article and the holographic filter, thereby providing accurate results at high speeds.

Abstract: The invention relates to a method and a device for the optical reading of information recorded on a support along a track in the form of diffracting elements. A diffraction pattern comprising a luminous central spot centered on the section of the track to be read and alternately dark and bright adjacent fringes is projected onto the support, the dark fringes adjacent to the central spot coinciding with the track sections in the neighborhood of the track section to be read. To that effect a pupil limited by two edges which are parallel to the direction of travel of the track is utilized, this pupil being placed against the reading objective.

Abstract: An optical component element which may be either used as an optical storage medium or as a component in an optical system characterized by a plurality of sub-holograms which will randomly divide a beam of coherent radiation in a plurality of partial beams with each of the sub-holograms producing a single partial beam. Each of the sub-holograms may be constructed so that the partial beam produced thereby exhibits a specific spatial configuration at specific locations in space with the spatial configurations being either focal points, focal lines, circular rings or sectors of a circle. Each of the sub-holograms may have a different area so that the partial beam formed thereby has a varying energy content. Preferably, the sub-holograms are constructed as sectors of a circle.

Abstract: A protective device is disclosed which is useful in protecting an operator against radiation emitted during welding. The protective device, which is employed in the presence of a surrounding light source, includes an interference filter which has a spectrally selective portion with bands for one or more of the ranges of wavelengths present in the emission spectrum of the surrounding light source and a radiation absorbing portion which attenuates the radiation to a value harmless to the eye without interfering with the spectrally selective portion of the interference filter.

Abstract: Undesired images and reflections are eliminated in an in-line infinity display system by tilting the bi-refringent package of the display system at an angle with respect to a plane normal to the optical axis of the curved mirror in the display system and the observer's location so that the undesired images and reflections are directed outside the observer's field of view.

Abstract: The invention relates to a method of eliminating errors in images of patterns which consist of periodically arranged individual images by optical filtering, only certain selected diffraction orders of the regular pattern to be imaged in the form of a ring or parts of a ring being employed for further imaging.

Abstract: An apparatus and method is disclosed for utilizing a low power light source in conjunction with a continuously scanned light beam deflector to form unblurred images of a vocabulary of characters at a plurality of discrete positions. The light source illuminates a scanning deflector from which an angularly scanned beam is directed towards a lens, from which it emerges as a linearly scanned beam. This linearly scanned beam illuminates a linear fly's eye lens array from which a plurality of substantially stationary beams are emitted, each of which may provide an unblurred image at a preselected position corresponding thereto.

Abstract: Superposed fine-detail multi-level patterns (e.g., superposed diffraction gratings having specified line spacing dimensions less than 10 micrometers and specified depth dimensions less than 5 micrometers) can be fabricated by linearly adding (e.g., by evaporation) an additional two-level pattern to an existent multi-level pattern or, alternatively, by linearly subtracting (e.g., by sputter or plasma etching) an additional two-level pattern to an existent multi-level pattern.

Abstract: A process and apparatus for improving image creation in a coherent light imagery system which involves directing diffused laser light onto a mirror having a rocking motion that will cause the reflected rays to sweep a two-dimensional area and focusing the reflected light through a diffuser before collimating same for use in image creation. More particularly, this invention creates the rocking motion by applying a combination of voltages to three independent piezo-electric crystals upon which the mirror is mounted.

Abstract: An apparatus for detecting the defects composed of non-linear components of a subject pattern, includes a laser source for illuminating the subject pattern by a laser beam, a Fourier-transform lens for projecting an information light from the pattern through a spatial filter onto a screen. The filter is placed on the Fourier-transform plane of the Fourier-transformed information light for intercepting the coherent light having information of the linear components, the filter having arm sections extending correspondingly to the linear components of said normal pattern, the outer periphery of said arm sections including curved sections protruding toward the intersecting point of the arms.

Abstract: An improved spatial filter for operation with high power laser beams is provided wherein a first gas flow system and a second gas flow system cooperate to enclose a cavity therebetween capable of accommodating a filter having an aperture located therein for spatially filtering the beam. The first and second gas flow systems are adapted for providing a first aerodynamic window across a beam entrance and a second aerodynamic window across a beam exit to maintain a selected gas pressure within the cavity while providing a transmission path for a high power laser beam. The first and second aerodynamic windows are in optical line of sight communication with one another through the aperture in the filter.

Abstract: A holographic optical memory utilizes an optical heterodyne technique to significantly increase the signal-to-noise ratio during the readout stage of operation. A light source provides a coherent light beam which is split into a readout beam and a local oscillator beam. The readout beam is directed to one of the holograms stored in the memory medium and a portion of the readout beam is diffracted by the hologram to form a reconstructed image of the bit pattern stored in the hologram at the reconstructed image plane. The local oscillator beam is superimposed with the diffracted portion of the readout beam. An optical frequency translator is positioned in either the readout beam or the local oscillator beam to cause the beams to have different optical frequencies. Therefore, when the two beams are superimposed, a beat frequency signal is produced. An array of detectors is positioned at the reconstructed image plane to receive the superimposed beams.