Patent · US Expired

Photoelectric sensor with variable light pulse frequency

US5331150A · kind A · utility

3Cited by
4References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 20, 1993
Grant dateJul 19, 1994
Priority date
Expiry dateApr 20, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01V8/12
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A photosensor is provided with a control circuit that is capable of varying the frequency of light pulses which energize a light source of the sensor. When four consecutive light pulses result in an identical status of a light sensitive component, the frequency of light pulses is slowed to conserve energy. However, when a change in state is recognized by the circuitry of the present invention, the frequency of light pulses is increased in order to more rapidly determine whether or not a change of status has actually occurred. This permits the photoelectric sensor to conserve energy while also being able to rapidly determine whether or not the light path of the photoelectric sensor has changed state from obstructed to unobstructed or, conversely, from unobstructed to obstructed.

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