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arXiv · 1903.01638

Phase-Retrieval-Based Wavefront Metrology for High Contrast Coronagraphy

Gregory R. Brady·Christopher Moriarty·Peter Petrone·Iva Laginja·Keira Brooks·Tom Comeau·Lucie Leboulleux·Remi Soummer
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Abstract

We discuss the use of parametric phase-diverse phase retrieval as an in-situ high-fidelity wavefront measurement method to characterize and optimize the transmitted wavefront of a high-contrast coronagraphic instrument. We apply our method to correct the transmitted wavefront of the HiCAT (High contrast imager for Complex Aperture Telescopes) coronagraphic testbed. This correction requires a series of calibration steps, which we describe. The correction improves the system wavefront from 16 nm RMS to 3.0 nm RMS.

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Gregory R. Brady, Christopher Moriarty, Peter Petrone, Iva Laginja, Keira Brooks, Tom Comeau, Lucie Leboulleux, Remi Soummer. 2019-03-05. Phase-Retrieval-Based Wavefront Metrology for High Contrast Coronagraphy. https://doi.org/10.1117/12.2314368

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