A vibration-resistance phase-shifting interferometer (PSI) was recently constructed and demonstrated. In this instrument, we have developed a method for actively compensating for vibration using a closed-loop phase servo system. An essential feature of this is phase modulating interference fringes fractionizing technology. This method can detect the fringe movement at 1/400 fringe interval, so fringes phase can be locked by the closed-loop feedback within 0.005 π. And the instrument implements phase shifting with the same piezoelectric transducer (PZT) that also compensates for vibration as feedback device. A microprogrammed control unit (MCU) is used to process phase information from photoelectric receiver, and then output the control signal to PZT driver. Experiments show that this solution is unique.

Date Published: 20 September 2002
PDF: 5 pages
Proc. SPIE 4927, Optical Design and Testing, (20 September 2002); doi: 10.1117/12.464059

Published in SPIE Proceedings Vol. 4927:
Optical Design and Testing
Zhicheng Weng; Jose M. Sasian; Yongtian Wang, Editor(s)