Patent · US Expired

Micro-displacement measuring apparatus using a semiconductor laser

US4806778A · kind A · utility

8Cited by
2References
4Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 26, 1986
Grant dateFeb 21, 1989
Priority date
Expiry dateFeb 26, 2006

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01D5/26
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A micro-displacement measuring apparatus using a semiconductor laser, comprises a compound resonator system containing the semiconductor laser, and a light detector receiving a light from said semiconductor laser. The compound resonator system is constructed such that a light from the semiconductor laser irradiates an object to be measured and the reflected light therefrom returns to the semiconductor laser, wherein the relationship between the reflectivity R.sub.f at the front facet of the semiconductor laser from which a laser light irradiates the object, and the reflectivity Rr at the rear facet of the semiconductor laser which is opposite the front facet is as follows: 0.1<R.sub.f Rr<1.

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