Patent · US Expired

Liquid crystal display device

US5977940A · kind A · utility

162Cited by
11References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 6, 1997
Grant dateNov 2, 1999
Priority date
Expiry dateMar 6, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2330/021
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Each pixel of a liquid crystal display device comprises a switching device for selecting a data signal, a memory portion for storing the data signal selected by the switching device and outputting an analog signal corresponding to the data signal, and a circuit for supplying an AC voltage corresponding to the analog signal to the liquid crystal layer. The liquid crystal layer is driven with a data signal stored in the memory portion or with an AC voltage corresponding to an analog signal corresponding to the data signal. With the signal stored in the memory portion, an AC voltage whose effective value or average value is controlled is supplied to the liquid crystal layer. Thus, unless a picture on the display is changed, since it is not necessary to supply the data signal, the peripheral driving circuit can be stopped. Consequently, although a picture is displayed in gradation mode, the power consumption can be remarkably reduced.

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