Patent · US Expired

LCD addressing system and method

US5485173A · kind A · utility

50Cited by
10References
79Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 1, 1991
Grant dateJan 16, 1996
Priority date
Expiry dateApr 1, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G3/2022
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

An addressing method and apparatus addresses faster responding liquid crystal display panels (LCDs) so that video rate, high information content LCDs having time constants on the order of 50 ms or less are perceived as having improved contrast by limiting peak voltage levels across the pixels. In a preferred embodiment, a first set of LCD electrodes is continuously driven with signals each comprising a train of pulses that are periodic in time, have a common period T, are independent of the information to be displayed, and are preferably orthonormal. Plural column signals are generated from the collective information states of the pixels defined by the overlap with a second electrode pattern. Each column signal is proportional to the sum, obtained by considering each pixel in the column, of the exclusive-or (XOR) products of the logic level of the amplitude of each row signal times the logic level of the information state of the pixel corresponding to that row. Hardware implementation comprises an external video source, a controller that receives and formats video data and timing information, a storage device that stores display data, a row signal generator, a column signal generat…

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