Patent · US Expired

Achromatic polarization inverters for displaying inverse frames in DC balanced liquid crystal displays

US6380997B1 · kind B1 · utility

33Cited by
35References
29Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 17, 1999
Grant dateApr 30, 2002
Priority date
Expiry dateDec 17, 2019

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F2413/08
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

This invention provides achromatic compound retarders, achromatic polarization switches, and achromatic shutters using the liquid crystal compound retarders. It further provides achromatic variable retardance smectic and nematic liquid crystal retarders. The achromatic compound retarders according to the invention are used to create achromatic inverters for display applications. The display comprises one or more retarders having in-plane retardance and in-plane orientation, at least one of the retarders being an actively controlled liquid crystal retarder, and a ferroelectric liquid crystal display, wherein the one or more retarders work in combination with the ferroelectric liquid crystal display to provide four states of brightness.

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