Patent · US Expired

Gradation driving method for bistable ferroelectric liquid crystal using effective cone angle in both states

US5465168A · kind A · utility

14Cited by
12References
22Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 28, 1993
Grant dateNov 7, 1995
Priority date
Expiry dateJan 28, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2320/0247
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A liquid crystal display includes a liquid crystal cell including a pair of substrates opposite to each other, each substrate having an electrode film and an orientation control layer thereon, and a ferroelectric liquid crystal filled between the substrates; and a pair of polarizing plates which are provided opposite to each other in the state of "cross nicol" on both sides of the liquid crystal cell; the ferroelectric liquid crystal being bistable in the liquid crystal cell, the polarizing plates being oriented in such a manner that one of their polarizing directions conforms to one of extinction positions of the ferroelectric liquid crystal under no electric field, the liquid crystal cell being applied with an alternating voltage for changing which has a positive portion which gives an apparent tilt angle from one stable state, and a negative portion which gives an apparent tilt angle relative to the other stable state, resulting in display with gray scale.

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