Patent · US Expired

Input/output pixel circuit and array of such circuits

US5204661A · kind A · utility

250Cited by
6References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 13, 1990
Grant dateApr 20, 1993
Priority date
Expiry dateDec 13, 2010

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F3/042
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A light sensing and display driving apparatus is operable independent of polling cycle providing a more accurate sensing of the patterns of illumination incident on an array of such apparatus, with a minimum of required interconnections per pixel. Each address line may simultaneously initialize one row of apparatus while enabling the subsequent row of apparatus. The apparatus is also compatible with elements capable of providing gain in the sensing mode, given that the photosensitive element is separate from the path across which voltage or current is measured. The display driving portion is compatible with standard active-matrix LCDs. The apparatus allows a minimum physical isolation between the sensing and display portions while maintaining sufficient electrical isolation to prevent the deleterious effects resulting from application of a display driving potential to sensing circuitry, and allows employing a timing scheme for both sensing and display driving within a short time period. The apparatus may be fabricated of amorphous silicon. The apparatus includes, inter alia, a conductive element interconnecting input and output terminals, a multiple-state sensing device whose state…

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