Patent · US Expired

Light source device for use in liquid crystal projectors

US5541746A · kind A · utility

12Cited by
6References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 10, 1995
Grant dateJul 30, 1996
Priority date
Expiry dateOct 10, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/315
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A light source device for use in liquid crystal projectors which comprises a reflector oriented toward a liquid crystal panel and having a reflecting surface formed by a paraboloid or ellipsoid, and a light source disposed at the focal position of the reflector. A converter is disposed on an optical axis extending from the light source to the liquid crystal panel for converging light emanating from the light source and reflected from the reflector in accordance with the size of an image display portion of the panel. The reflecting surface of the reflector has a great focal distance so that the spreading angle of the reflected light is not greater than 8 deg.

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