Interferometric sensor based on coherent imaging of gratings.
A sensitive interferometric sensor scheme that is based on coherent imaging of a first phase grating onto a second phase grating, their periods accurately matched, is suggested. Experimental data, obtained with a setup based on the suggested scheme, are presented. The sensor was found capable of measuring an angular tilt of a mirror less than 0.5 microrad. Compared with a previously suggested measuring scheme, the novelty of the one presented here is the inclusion of a second set of gratings, which eliminates measurement ambiguity. Some characteristics of the sensor scheme are discussed.
Magnusson
Anders
A
Photonics Laboratory, Department of Microelectronics, Chalmers University of Technology, SE-412 96 Göteborg, Sweden. andersm@elm.chalmers.se
Moud
Kamyar Kazemi
KK
Hård
Sverker
S