Patent · US Expired

Method of driving a matrix-type liquid crystal display device

US5216415A · kind A · utility

39Cited by
6References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 13, 1991
Grant dateJun 1, 1993
Priority date
Expiry dateDec 13, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2310/063
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A method of driving a matrix-type liquid crystal display device utilizing a liquid crystal layer sandwiched between a plurality of scanning electrodes and a plurality of signal electrodes extending generally perpendicular to the scanning electrodes, which comprises the steps of erasing a display screen by bringing it into either a light transmitting state or a light scattering state, writing by which pixels each at a point of intersection between the scanning and signal electrodes are selectively reversed in optical state, and retaining each of the pixels in the optical state once assumed immediately after the writing step. During the erasing step, all of the pixels are applied with a high alternating voltage or a high direct current voltage. During the writing step, the scanning electrodes are line-sequentially selected and the signal electrodes are applied with a signal of a waveform effective to apply a high voltage to some of the pixels desired to be reversed in optical state and a low voltage to some of the pixels desired to be retained. During the retaining step, a low alternating voltage or a low direct current voltage is applied to all of the pixels. One of the voltage wave…

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