Patents by Inventor Stephen A. Benton

Stephen A. Benton has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6414727
    Abstract: A laser projection video system and a holographic screen. The system includes a pulsed laser video image system with a holographic screen to receive the full color video image, which screen has a holographic layer (layer 1) to reflect back the full color video image to the viewer and to transmit through the screen the ambient light to provide high video picture contrast.
    Type: Grant
    Filed: July 27, 1999
    Date of Patent: July 2, 2002
    Assignee: Corporation for Laser Optics Research
    Inventor: Stephen A. Benton
  • Patent number: 6351280
    Abstract: An autostereoscopic display system is capable of tracking one or more users within a viewing zone and presenting complementary stereoimages to each of the viewer's (or viewers') eyes. Polarization is used to segregate the images that are to be directed to different spatial regions. The two images are interdigitated within a single display—that is, each band of image points from the first image alternates with a band of image points from the second image on the display. The bands of the first image are polarized in a first mode and the bands of the second image are polarized in a second mode orthogonal to the first, e.g., through use of a liquid-crystal display (LCD) in which alternating, contiguous bands of pixels correspond to bands of one or the other image, and a “patterned polarizer” also organized into bands and aligned with the pixel bands.
    Type: Grant
    Filed: November 20, 1998
    Date of Patent: February 26, 2002
    Assignee: Massachusetts Institute of Technology
    Inventor: Stephen A. Benton
  • Patent number: 6211848
    Abstract: A user is able to interact with and modify an electronic holographic image using a force-feedback (or haptic) device, which is capable of sensing and reporting the 3D position of its hand-held stylus and “displaying” appropriate forces to the user. Thus, a user can feel and modify specified shapes in the haptic workspace. The haptic workspace is precisely registered with the free-standing, spatial image displayed by a holographic video (holovideo) system. In the coincident visuo-haptic workspace, a user can see, feel, and interact with synthetic objects that exhibit many of the properties one expects of real ones, and the spatial display enables synthetic objects to become a part of the user's manipulatory space.
    Type: Grant
    Filed: February 9, 1999
    Date of Patent: April 3, 2001
    Assignee: Massachusetts Institute of Technology
    Inventors: Wendy Plesniak, Ravikanth Pappu, Stephen Benton
  • Patent number: 5172251
    Abstract: A three dimensional display system includes a laser for generating a laser light signal. The signal is expanded and collimated using a traditional lens system and is directed to an acousto-optic modulator wherein it is modulated to generate a three dimensional image such as a holographic image. The modulation signal for the modulator is provided by a data processing system. The data processing system applies signals to the modulator that encode a diffraction pattern. The diffraction pattern is realized by the modulator upon application of the signals and the three dimensional image is produced by the modulated light signals. The image is demagnified by a demagnifier, and subsequently, imaged by a viewing lens. A horizontal scanner continuously multiplexes segments of the holographic image and compensates for the motion of segments across the modulator. A vertical scanner is provided to properly vertically position horizontal lines of the holographic image.
    Type: Grant
    Filed: April 12, 1990
    Date of Patent: December 15, 1992
    Assignee: Massachusetts Institute of Technology
    Inventors: Stephen A. Benton, Joel S. Kollin
  • Patent number: 5121229
    Abstract: A three-step process is combined with an edge-lit system to provide a self-contained, maximally-compact holographic display. In one embodiment, a hologram is affixed to an upstanding transparent support plate mounted through the top of a housing in which the hologram is edge-illuminated with white light from a source in the housing immediately beneath the plate to generate brilliant, sharp and deep multi-color images which straddle the hologram plane. In another embodiment, the transparent support plate is mounted in a frame which carries the edge-illumination source. All displays may either be free-standing or wall-mounted, as desired.
    Type: Grant
    Filed: August 9, 1989
    Date of Patent: June 9, 1992
    Assignee: Msssachusetts Institute of Technology
    Inventors: Stephen A. Benton, Sabrina M. Birner
  • Patent number: 4986619
    Abstract: Holographic color control systems are disclosed for the production of pseudocolor holograms by in-situ sequential swelling of an emulsion and exposure to three color separation images with a single wavelength reference light source. The resulting holograms yield images in three color primaries with excellent color registration and mixing, producing a full gamut of mixed colors, pastels and neutrals with three-dimensional perspective.
    Type: Grant
    Filed: October 30, 1989
    Date of Patent: January 22, 1991
    Assignee: Massachusetts Institute of Technology
    Inventors: Julie L. Walker, Stephen A. Benton
  • Patent number: 4834476
    Abstract: Methods and devices for recording and projecting holographic stereograms are disclosed. In one aspect of the invention, a concave semi-cylindrical ("alcove") display system is disclosed in which an image is projected in front of the alcove. The display system provides a very wide angle of view approaching 180 degrees (compared to the 30 degrees of a typical flat hologram) that allows the viewer to look around most of the image content. This type of display is particularly useful in computer aided design projects where designers wish to present an overall three-dimensional display of their work. In another aspect of the invention, a holographic printer and procedures for recording a stereogram are disclosed as well as techniques for producing "predistorted" images for the sub-holograms. A digital processing technique is disclosed which effectively predistorts the source two-dimensional image set for the stereogram to compensate for the effects of the display geometry.
    Type: Grant
    Filed: January 12, 1988
    Date of Patent: May 30, 1989
    Assignee: Massachusetts Institute of Technology
    Inventor: Stephen A. Benton
  • Patent number: 4498729
    Abstract: A method of producing achromatic holographic images of an object, and a diffraction grating useful for making an achromatic hologram. The method comprises the steps of making a monochromatic hologram on a first photographic plate, making a diffraction grating by exposing a second photographic plate to a series of colinear point sources of mutually coherent monochromatic light, developing and bleaching the exposed plate to produce the diffraction grating, making a second hologram by exposing a third photographic plate to an image from a narrow elongated strip of the first hologram with the diffraction grating in the optical path, and making an achromatic hologram by holographically recording the image produced by illuminating the second hologram with monochromatic light on a fourth photographic plate.
    Type: Grant
    Filed: August 13, 1979
    Date of Patent: February 12, 1985
    Assignee: Polaroid Corporation
    Inventor: Stephen A. Benton
  • Patent number: 4486070
    Abstract: Apparatus for illuminating transmission holograms from the rear with an illumination source located in front of the hologram, comprising a reflector and a light trap adapted to be mounted behind the hologram at a location chosen to reflect light from the source through the hologram as though from a source behind the hologram, while reflecting ambient light from the direction of an observer of the hologram into the trap.
    Type: Grant
    Filed: October 7, 1983
    Date of Patent: December 4, 1984
    Assignee: Polaroid Corporation
    Inventor: Stephen A. Benton
  • Patent number: 4445749
    Abstract: A method of making achromatic holographic stereograms in which projected images from a sequence of two-dimensional transparencies of a scene taken from a sequence of successively displaced positions are sequentially holographically recorded on adjacent strips of a photographic plate while the plate is inclined at an acute angle to the optical axis of projection of the images. The sequence of holographic strip images so recorded are re-recorded on a second hologram using a beam conjugate to the original reference beam to illuminate the strip hologram. The second holographic recording is done with the aid of a vertically inclined collimated reference beam of coherent light. Upon illumination of the second hologram with white light, a three-dimensional image of the original scene may be viewed by an appropriately placed observer which is achromatic over an extended angle of view and an extended apparent scene depth.
    Type: Grant
    Filed: June 6, 1980
    Date of Patent: May 1, 1984
    Assignee: Polaroid Corporation
    Inventor: Stephen A. Benton
  • Patent number: 4431265
    Abstract: Apparatus for viewing superposed stereographic images each presented in a different color, comprising a color television receiver having a dual dichroic polarizing filter over the viewing screen, and a pair of spectacles having orthogonally polarized lenses for viewing the screen through the filter.
    Type: Grant
    Filed: December 31, 1980
    Date of Patent: February 14, 1984
    Assignee: Polaroid Corporation
    Inventor: Stephen A. Benton
  • Patent number: 4429947
    Abstract: Apparatus for illuminating transmission holograms from the rear with an illumination source located in front of the hologram, comprising a reflector and a light trap adapted to be mounted behind the hologram at a location chosen to reflect light from the source through the hologram as though from a source behind the hologram, while reflecting ambient light from the direction of an observer of the hologram into the trap.
    Type: Grant
    Filed: April 13, 1981
    Date of Patent: February 7, 1984
    Assignee: Polaroid Corporation
    Inventor: Stephen A. Benton
  • Patent number: 4415225
    Abstract: A process of making holographic images comprising the steps of recording a hologram of a parallax limited aerial image formed by a lens on a recording surface with a reference beam at an angle of incidence to the recording surface that is preferably equal and opposite to the angle of incidence of the object beam to the recording surface, and illuminating the hologram with a beam of diverging or collimated light, preferably at the angle of incidence of the object beam to the recording surface and directed oppositely to the direction of the object beam during recording. Illumination can be with white light. The hologram may comprise superposed recordings of the aerial image made with light of different wavelengths to produce full color holographic images.
    Type: Grant
    Filed: November 10, 1980
    Date of Patent: November 15, 1983
    Assignee: Polaroid Corporation
    Inventors: Stephen A. Benton, William R. Houde-Walter, Herbert S. Mingace, Jr.
  • Patent number: 4217405
    Abstract: Volume dielectric holograms are prepared by methods which have in common the intra-emulsion diffusion transfer of silver atoms within the emulsion by a process of dissolving undeveloped silver halide, and diffusing and precipitating said dissolved silver on precipitation sites provided by the development of the exposed silver halide. The resulting metallic silver is then rehalogenated to substantially reconstitute the original silver halide volume of the emulsion.
    Type: Grant
    Filed: October 14, 1975
    Date of Patent: August 12, 1980
    Assignee: Polaroid Corporation
    Inventor: Stephen A. Benton
  • Patent number: 3944322
    Abstract: A holographic arrangement is provided with light filtering means for transmitting only those light rays to the hologram which are incident to the hologram at the prescribed angles required for substantial diffraction while at the same time operating to preclude the transmission of other light rays to the hologram which would otherwise be incident to the hologram at angles outside the prescribed range of angles required for substantial diffraction by the hologram. In this manner background light which would otherwise be transmitted through a hologram so as to degrade the quality of a stereoscopic image reconstructed from the hologram is precluded from ever reaching the viewing area.
    Type: Grant
    Filed: January 16, 1975
    Date of Patent: March 16, 1976
    Assignee: Polaroid Corporation
    Inventor: Stephen A. Benton