Patent · US Expired

Color sensing method and device therefor

US4804833A · kind A · utility

6Cited by
10References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 5, 1986
Grant dateFeb 14, 1989
Priority date
Expiry dateSep 5, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01J2003/507
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method for sensing the color of incident light with a color sensing device, the color sensing device being a photoelectric device comprising an n-type or p-type amorphous silicon layer, being characterized in the following steps; measuring a first photocurrent of the photoelectric device generated by incident light when an electrical voltage having a predetermined parity is applied thereto; measuring a second photocurrent of the photoelectric device generated by the same incident light when another electrical voltage having a parity opposite to the predetermined parity is applied thereto, calculating the ratio of the first photocurrent to the second photocurrent; and identifying the color of incident light according to the ratio obtained. A color sensing device, comprising: two elements including an n-type or p-type amorphous silicon layer; an electric power source for applying a positive voltage and a negative voltage to the two elements at the same time, respectively; and a divider means for calculating a ratio of the two photocurrents which flows in each elements.

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