Patent · US Expired

Apparatus and method for providing a gray scale capability in a liquid crystal display unit

US4840460A · kind A · utility

112Cited by
2References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 13, 1987
Grant dateJun 20, 1989
Priority date
Expiry dateNov 13, 2007

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F2203/30
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A liquid crystal display is described that includes gray scale capability. Each pixel of the display is subdivided into a plurality of subpixels. Each subpixel includes an effective capacitor, with the liquid crystal material contained between the effective capacitor plates, and includes a control capacitor coupled in series with the effective capacitor. By controlling the capacitance of the control capacitors of the subpixels, selected subpixels can be activated as a function of the voltage applied across the series capacitors. By controlling the number of subpixels that are activated by the applied voltage, a gray scale capability can be provided for a liquid crystal display.

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