Patents Assigned to Richmond Holographic Research and Development Ltd
  • Projection system
    Patent number: 6095652
    Abstract: A projection system incorporating a screen (2, 14) with a substantially achromatic response in a direction substantially perpendicular to the plane of the screen. The screen (2, 14) comprises a diffraction grating (4), means (5) for attenuating zero order and a diffuse holographic optical element (6). The system further comprises a focusing element with positive optical power. The aggregate optical power of the grating and the holographic optical element is substantially less than that of the focusing element.
    Type: Grant
    Filed: June 12, 1998
    Date of Patent: August 1, 2000
    Assignee: Richmond Holographic Research and Development, Ltd.
    Inventors: David John Trayner, Edwina Margaret Orr
  • Viewing apparatus
    Patent number: 5600454
    Abstract: Viewing apparatus for providing a viewer with an apparent 3-D image includes a diffusing holographic optical element screen, horizontal strip lamps for illuminating the screen from a plurality of different positions and a liquid crystal display for effecting spatial modulation of the light from the respective positions so as to illuminate respective images on the screen. The arrangement is such as to provide a plurality of viewing zones whereby each image can be seen only from a corresponding one of the zones.
    Type: Grant
    Filed: January 14, 1994
    Date of Patent: February 4, 1997
    Assignee: Richmond Holographic Research and Development Ltd
    Inventors: David J. Trayner, Edwina M. Orr