Patent · US Expired

Polarizing conversion unit, illuminating device and projector using them

US5590942A · kind A · utility

11Cited by
6References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 8, 1993
Grant dateJan 7, 1997
Priority date
Expiry dateSep 8, 2013

Classification

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

Abstract

A polarizing conversion unit is disclosed. The unit is provided with a polarizing beam splitter for separating light from a light source into first and second polarized lights differing in polarized state from each other, polarizing conversion means for varying the polarized state of the first polarized light and making it substantially coincident with the polarized state of the second polarized light, and reflecting means for reflecting the first or second polarized light, at least a portion of that surface of the outer peripheral portion of the polarizing conversion unit which is parallel to the optical path of the light functioning as a reflection surface.

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