Patent · US Expired

Optical displacement sensor

US5798826A · kind A · utility

3Cited by
2References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 20, 1997
Grant dateAug 25, 1998
Priority date
Expiry dateMar 20, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B11/026
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A optical displacement sensor comprises optical output detecting unit for detecting an optical output from the semiconductor laser, which changes in accordance with the phase of return light reflected by the external reflection unit, when an optical distance between the semiconductor laser and the external reflection unit changes at a change rate, optical distance modulation unit for changing the optical distance at predetermined periods by an amount of modulation of the optical distance at a rate higher than the change rate, and a detection circuit system for detecting the amount and direction of change of the optical distance based on an optical output from the optical output detecting unit detected in synchronism with a timing of modulating the optical distance by the optical distance modulation unit.

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