Phase Retrieval Algorithm for Form Testing Metrology in Production Environment

Stephan Stuerwald, Robert Schmitt
unpublished
Form testing interferometry permits a fast, non-tactile and full-field quantitative phase imaging of components in ultra precise manufacturing. To reduce the influence of vibrations under manufacturing conditions, it is most common to use the FT-based spatial carrier phase measurement technique (SCPM) which requires only a single interferogram recording. The utilization of a generalized, relatively new spatial phase-shifting method operating in the position space opens up prospects for reduced
more » ... hase noise and less reconstruction errors of the calculated phase-map under production conditions. Therefore this phase-shifting technique is investigated for applicability in machine integrated interferometric form testing of optical lenses. A characterization of the algorithm and a comparison with the commonly used FT-based algorithm is performed. As a reference, measurements are carried out with a coordinate measuring machine with nanometre accuracy.
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