Patent · US Expired

Multi-color tunable filter

US4350413A · kind A · utility

4Cited by
6References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 14, 1980
Grant dateSep 21, 1982
Priority date
Expiry dateApr 14, 2000

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/015
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A semi-conductor multi-color tunable filter is created by multiple epitaxial layers of varying composition. An AC modulation voltage is superimposed on a sweep bias to periodically shift the fundamental absorption edge of each individual epitaxial layer. This arrangement permits a unique voltage to be associated with a particular color. A lock-in filter matches colors observed at a detector with the voltage present for a given observation.

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