Patent · US Expired

Optical systems for reflective LCD's

US6490087B1 · kind B1 · utility

52Cited by
9References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 10, 2000
Grant dateDec 3, 2002
Priority date
Expiry dateApr 10, 2020

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S359/90
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Optical systems for use with reflective LCDs (8,9,32,34,36) are provided. The systems include a polarization beam splitter (5) which can be composed of polarization beam splitting cubes (26) having sheet polarizers (30) and/or half wave plates (28) at their mating surfaces. By orienting the half wave plates (28) so that they convert S polarization to P polarization and P polarization to S polarization, the polarization beam splitter (5) can provide a high contrast ratio at a viewing screen between light from the “on” and “off” pixels of the reflective LCDs (8,9,32,34,36).

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