Patent · US Expired

Interferometer

US4830496A · kind A · utility

56Cited by
5References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 22, 1988
Grant dateMay 16, 1989
Priority date
Expiry dateJan 22, 2008

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B2290/25
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A reference mirror (50) in an interferometer is fixed in position with respect to a laser (34). A refractive block (40) having parallel upper and lower surfaces is mounted for pivoting about a pivot axis (60) parallel to the reference mirror (40). The refractive block (40) is disposed in the path of the light beam (36) produced by the laser (34), and it includes a partially reflective surface (42) on its lower face that divides the incident beam (36) into two components (44 and 46), which travel along different paths, in which they are reflected from different portions (48 and 54) of the surface of the reference mirror (50) and from different portions (52 and 56) of a reflective surface on the upper face of the refractive block (40). A second partially reflective coating (58) rejoins portions of the two components to form an exit beam (32) in which the radiation from the two beams interferes in accordance with the angle of the refractive block (40). The angle that the exit beam (32) makes with the surface of the reference mirror (50) is independent of the angle of the refractive block (40).

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