Patent · US Expired

Color display system

US4345258A · kind A · utility

28Cited by
7References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 15, 1980
Grant dateAug 17, 1982
Priority date
Expiry dateDec 15, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG09G3/02
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A projection and display system utilizes a modulated laser beam whose energy distribution in the "P" and "S" polarization planes is controlled by a half wavelength retardation plate. The laser beam is then deflected along the X and Y axes and passes through a dichroic polarizer cube which splits the beam to focus upon a P channel smectic liquid crystal display cell and an S channel smectic liquid crystal display cell to selectively form images on one or both of the display cells. At the same time, the formed images are projected by the use of light that is split into two colored light beams by a second dichroic cube and is reflected to back light the images in each of the display cells. The projected beams then pass back through the first dichroic cube where they are recombined and passed through a projection lens system to a suitable display screen. To selectively erase the information on either of the display cells, an AC bias is applied to that display cell during the laser scan thereof.

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