Patent · US Expired

Display optical apparatus having a rotary compensator to improve display contrast

US6624862B1 · kind B1 · utility

25Cited by
8References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 28, 2000
Grant dateSep 23, 2003
Priority date
Expiry dateMar 28, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F2413/08
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A display optical apparatus is provided with: a polarizing plate transmitting illuminating light having a predetermined polarization direction; a reflective liquid crystal display device reflecting the illuminating light transmitted by the polarizing plate as projected light of a polarization condition that differs according to pixel information for each pixel; and a phase plate changing the polarization conditions of the illuminating light and the projected light and directing the illuminating light and the projected light to the polarizing plate. The phase plate is disposed between the reflective liquid crystal display device and the polarizing plate. The black level of the projected light is adjusted by rotating the principal axis direction of the phase plate.

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