Heterodyne interferometer arrangement with tunable lasers, a heterodyne interferometer, a comparison interferometer and a reference interferometer

US5784161A · kind A · utility

Assignee

• Carl Zeiss Jena GmbH · DE

Inventors

• Karl-Heinz Bechstein · Jena, DE
• Beate Moeller · Jena, DE
• Klaus Salewski · Greifswald, DE
• Andreas Wolfram · Karlsburg, DE

Key dates

• Filing date: Jun 20, 1996
• Grant date: Jul 21, 1998
• Expiry date: Jun 20, 2016

Classification

• Technology area (CPC G): Physics
• CPC primary: G01B2290/70
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

The present invention is directed to a heterodyne interferometer arrangement with tunable laser light sources for absolute distance measurement. The phase angle changes which occur in the synthetic interference signals when varying the laser frequencies are recorded and evaluated. The arrangement also enables error-free distance measurement in the event of a change in the mathematical sign of the phase changes due to frequency jitter.