Patent · US Expired

Display apparatus and method

US6909473B2 · kind B2 · utility

38Cited by
42References
82Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 7, 2002
Grant dateJun 21, 2005
Priority date
Expiry dateAug 25, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F2203/02
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A projection display apparatus (10) uses a modulation optical system (200) that includes a liquid crystal device (210) in combination with a wire grid polarization beamsplitter (240), a wire grid polarization analyzer (270) and a projection lens (285) to form an image. In order to achieve high contrast and maintain high brightness levels, a compensator (260) is provided for minimizing leakage light for pixels in the black (OFF) state. A number of configurations are possible, such as with the compensator (260) disposed in the optical path between the liquid crystal device (210) and the wire grid polarization beamsplitter (240) and with a secondary compensator (265) disposed between wire grid polarization analyzer (270) and the wire grid polarization beamsplitter (240).

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