Patent · US Expired

Visible light sensor mechanism for constant brightness projection systems

US6734957B2 · kind B2 · utility

3Cited by
7References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 31, 2002
Grant dateMay 11, 2004
Priority date
Expiry dateAug 20, 2022

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N5/57
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An apparatus for collecting and sensing light in a projector, comprising a cold mirror positioned directly in the incident light path from a lamp and illumination optics of the projector for reflecting a large portion of visible light towards a light imaging device while transmitting IR and UV light and a small portion of the visible light; a secondary mirror for reflecting the small portion of the visible light, an integrating box positioned to collect and integrate the small portion of visible light, a light tube in optical communication with the integrating box for further integrating and attenuating the small portion of visible light, and an electro-optic device within the light tube for measuring the small portion of visible light within the light tube and generating an electrical signal in response thereto.

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