Interferometer for measuring optical phase differences

US4872755A · kind A · utility

Assignee

• Carl Zeiss Stiftung · DE

Inventor

• Michael Kuchel · Oberkochen, DE

Key dates

• Filing date: Mar 7, 1988
• Grant date: Oct 10, 1989
• Expiry date: Mar 7, 2008

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B6/2861
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

For generating several interferograms which differ from each other in the relative phase position between the interfering partial beams, a light source is utilized having a coherence length less than the optical path difference between the two component beams in the measuring path of the interferometer. Furthermore, at least one optical delay device is provided which splits the beam into two component beams and which generates an optical path difference between these component beams which is approximately the same as the optical path difference of the partial beams in the measuring path of the interferometer. Thereafter, the delay device again unites the component beams congruently.