Robust, common path, phase shifting interferometer and optical profilometer.

TitleRobust, common path, phase shifting interferometer and optical profilometer.
Publication TypeJournal Article
Year of Publication2008
AuthorsR Tumbar, DL Marks, and DJ Brady
JournalApplied Optics
Volume47
Start PageB32
Issue10
PaginationB32 - B43
Date Published04/2008
Abstract

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.

DOI10.1364/ao.47.000b32
Short TitleApplied Optics