Patent · US Expired

Arrangement for and method of detecting an object in an area subject to environmental variations

US5508511A · kind A · utility

37Cited by
18References
43Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 24, 1994
Grant dateApr 16, 1996
Priority date
Expiry dateMay 24, 2014

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE06B2009/6836
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Environmental variations in ambient light and temperature are eliminated in arrangements for and methods of detecting objects in areas exposed to such variations by generating a differential measurement value indicative of the difference between two signals derived from two light sources, both signals being affected in the same way and extent by the environmental variations.

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