Patent · US Expired

Contrast adjustment circuit for liquid crystal display

US5517212A · kind A · utility

20Cited by
6References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateAug 2, 1994
Grant dateMay 14, 1996
Priority date
Expiry dateAug 2, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G3/36
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A contrast adjustment circuit for a liquid crystal display which is connected, when to be used, to an electronic apparatus such as a computer. The contrast adjustment circuit comprises an adjustment voltage supply circuit provided in an electronic apparatus, a reference voltage generation circuit provided in the liquid crystal display for generating a reference voltage substantially equal in absolute value to a contrast peak voltage of the liquid crystal display, and an operational amplifier for comparing the reference voltage and an adjustment voltage and supplying a voltage difference between the reference voltage and the adjustment voltage to a driving voltage input terminal of the liquid crystal display.

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