Patent · US Expired

Combined light source for projection display

US7090357B2 · kind B2 · utility

21Cited by
80References
39Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 2003
Grant dateAug 15, 2006
Priority date
Expiry dateMar 13, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N9/3164
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

High pressure mercury arc lamps are commonly used as the illumination source in many projection systems. Such lamps may be deficient in either output power or spectrum, and so it is desirable to combine the light from the lamp with light from a second light generator. The second light generator may be another mercury lamp or a solid state source, such as one or more light emitting diodes. Different ways of combining light from two light generators are described. The second light source may be an arrangement of a number of red LEDs that supplements the red light produced by the mercury light. A tunnel integrator may be used to homogenize the combined light beam and to reduce the angular separation between the light beams from the two light generators.

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