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arXiv · 1510.03791

Focal plane wave-front sensing algorithm for high-contrast imaging

JiangPei Dou·DeQing Ren·YongTian Zhu·Xi Zhang
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Abstract

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star. A major limitation for such direct imaging is the speckle noise that is induced from the wave-front error of an optical system. We derive an algorithm for the wave-front measurement directly from 3 focal plane images. The 3 images are achieved through a deformable mirror to provide specific phases for the optics system. We introduce an extra amplitude modulation on one deformable mirror configuration to create an uncorrelated wave-front, which is a critical procedure for wave-front sensing. The simulation shows that the reconstructed wave-front is consistent with the original wave-front theoretically, which indicates that such an algorithm is a promising technique for the wave-front measurement for the high-contrast imaging.

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JiangPei Dou, DeQing Ren, YongTian Zhu, Xi Zhang. 2015-10-13. Focal plane wave-front sensing algorithm for high-contrast imaging. https://doi.org/10.1007/s11433-009-0158-2

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