Patent · US Active

Chromatic compensation in Fizeau interferometer

US7580135B2 · kind B2 · utility

1Cited by
2References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 22, 2007
Grant dateAug 25, 2009
Priority date—
Expiry dateAug 20, 2027

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01B9/02063
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

The focus of the collimating lens in the optical train of a Fizeau interferometer is adjusted to change the power of the test beam illuminating the transmission sphere. As a result, the rays can be made sufficiently perpendicular to the reference surface to eliminate the chromatic focus shift and non-common path errors produced by a light source of wavelength different from the design wavelength of the transmission sphere. By making the position of the collimating lens relative to the beam expander adjustable along the optical axis over some small range, illumination sources of various wavelength can be used in the same interferometer.

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