×

Rear projection screen

  • US 4,936,652 A
  • Filed: 03/08/1989
  • Issued: 06/26/1990
  • Est. Priority Date: 09/28/1988
  • Status: Expired due to Term
First Claim
Patent Images

1. A transparent rear light projection screen comprising a picture forming element having on its rear side outwardly extending, parallel elongate convex lenses the focal length of each of which is equal to the thickness of the screen element and which lenses transmit light coming from behind to the front of the screen, which light is only deflected at the convex lenses, and having on its front side outwardly extending elongate projections parallel to said convex lenses, said projections having tops from which the light transmitted from said convex lenses can emit, said front side having V-shaped grooves between the tops of said projections, said grooves being covered or filled up with material impenetrable to light to increase contrast, and having a depth which is at least twice the width of the width of said tops of said projections, and which is greater than one fourth the thickness of the picture forming element.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×