×

Holographic display element

  • US 5,153,751 A
  • Filed: 04/26/1991
  • Issued: 10/06/1992
  • Est. Priority Date: 04/27/1990
  • Status: Expired due to Term
First Claim
Patent Images

1. A holographic display element attached to a transparent plate member for projecting light rays carrying images of display information onto the display element from a luminous image source positioned on a predetermined first side of the display element, the display element comprising:

  • a first reflection hologram onto which said light rays are to be projected, the first reflection hologram having such diffraction characteristics that, when collimated external light is incident thereon from a second side opposite to said first side and diffracted, light in the visible region of wavelengths is diffracted into a predetermined range of angles in a predetermined plane; and

    a second reflection hologram which is superposed on said first reflection hologram on said second side, the second reflection hologram being different from said first reflection hologram in diffraction characteristics such that, when collimated external light is incident on the display element from said second side and diffracted by the display element, diffraction of light in the visible region of wavelengths into said predetermined range of angles is inconspicuous to a person viewing the display element from said second side.

View all claims
  • 2 Assignments
Timeline View
Assignment View
    ×
    ×