Patent · US Expired

Thermal imager

US4868389A · kind A · utility

7Cited by
3References
15Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 26, 1988
Grant dateSep 19, 1989
Priority date
Expiry dateApr 26, 2008

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04N25/21
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A thermal imager is provided with a signal processing circuit which compensates for differences in the sensitivities of the thermal detectors. The compensating circuit produces a signal dependent on the mean output of each detector over a predetermined period, stores the signal in a storage device at a frequency of not more than once each field and applies a correction signal derived from the storage device to the detector.

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