Patent · US Expired

Display apparatus

US5239322A · kind A · utility

64Cited by
6References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 15, 1991
Grant dateAug 24, 1993
Priority date
Expiry dateMay 15, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/3167
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

There is provided an apparatus for displaying an image on a screen by projecting a reading light from a light source onto a spatial light modulator of reflective type in which the image is written, and projecting a reflected light from the modulator corresponding to the image onto the screen through a projection lens, the modulator, lens and screen being provided so that their optical axes are in agreement on one optical path. The apparatus comprises an optical device provided between the lens and screen for the reading light toward the modulator and passing the reflected light to the screen and a converging element for converging the reading light on the position which is on the optical axis of the lens and located between the lens and screen so that the reading light thus turned becomes a parallel pencil beam which is projected onto the modulator in parallel with the optical axis.

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