Patent · US Expired

Dual-fresnel field lens for a single-panel LCD projection system

US5940152A · kind A · utility

11Cited by
4References
5Claims
0Family size

Inventors

Key dates

Filing dateMay 1, 1997
Grant dateAug 17, 1999
Priority date
Expiry dateMay 1, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B3/08
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A dual-Fresnel field lens liquid crystal display projection system which includes first and second flat Fresnel lenses having their faceted surfaces facing one another and positioned adjacent to one another along the optical axis of the system between a liquid crystal display light modulator and the entrance aperture to a projection lens assembly to form a field lens assembly for the projection system.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.