Patent · US Expired

Display device

US5684504A · kind A · utility

23Cited by
9References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 20, 1995
Grant dateNov 4, 1997
Priority date
Expiry dateJun 20, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G2320/0209
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

Color display device for projection of the type comprising a light-switching device, for example a device illuminated by successive light strips of different colors (sequential color single panel projector) in which a display device with a matrix of pixels driven by active switching elements is advantageously used for the light-switching device (based on, for example ferro-electric liquid crystal material), the drive being chosen to be such that there is no memory action to a subsequent sub-frame. Due to the voltage-independent capacitance, notably of ferro-electric pixels, a simple drive mode can be used in which a simple correction for possible capacitive effects is sufficient. Notably in a two-pole drive mode, use can be made of the relatively longer time available for (optical) reset. A combination of the two types of drive mode is possible. Compensation of DC effects within a small part of the frame period is also possible without affecting the contrast.

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