Wavefront Correction in a Shaped-Pupil Coronagraph Using a Gerchberg-Saxton-Based Estimation Scheme
نویسنده
چکیده
The detection of extra-solar terrestrial planets requires the use of space-based high-contrast imaging. Stellar photon noise as well as light thrown about by system aberrations necessitate the use of a high quality light suppression system and a method for wavefront correction. We present here a wavefront estimation scheme to be used with estimate-based correction for the shaped pupil coronagraph. In order to properly estimate the field in a reimaged pupil plane, we employ the use of the iterative Gerchberg-Saxton estimation algorithm between it and a second-focus image plane. We utilize the correction algorithm to overcome an ambiguity inherent in Gerchberg-Saxton estimation.
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