Patent · US Expired

Liquid crystal light valve showing an improved display contrast

US5051570A · kind A · utility

180Cited by
18References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 19, 1990
Grant dateSep 24, 1991
Priority date
Expiry dateJan 19, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/136277
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

An optically-addressed liquid crystal light valve comprises a transparent insulating substrate having either one-dimensional or two-dimensional arrays of optical switching elements thereon which can perform switching with an incident light, another opposing transparent substrate having transparent electrodes and a liquid crystal sandwiched therebetween. Each of the light switching elements comprises a photo-detector circuit and a thin-film-transistor (TFT) drive circuit. The photo-detector circuit comprises a serially connected photodiode and a passive element such as capacitor or resistor. The TFT drive circuit receives as input the voltage produced from the photo-detector circuit, while the output voltage from the TFT drive circuit is applied to one pixel electrode for the liquid crystal.

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