Robust, common path, phase shifting interferometer and optical profilometer.
We describe an improved implementation of our previously reported common-path, phase shifting, and shearing interferometer. Using a time-multiplexed phase shifting scheme, we demonstrate higher sampling resolution, better light sensitivity, and use of arbitrary phase shifting algorithms. We describe microscopic imaging of the surface profile of a copper-plated silicon wafer and demonstrate that the system is vibration insensitive with approximately lambda/100 repeatability. In a more general discussion of our method, we describe the different functional elements and suggest alternative designs and improvements. Possible uses include full-field coherent imaging and high dynamic range wavefront sensing, which we briefly discuss.
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Remy
R
Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York 14853, USA. rt77@cornell.edu
Marks
Daniel L
DL
Brady
David J
DJ