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arXiv · 1406.2364

A high-contrast coronagraph for earth-like exoplanet direct imaging: design and test

C. C. Liu·D. Q. Ren·J. P. Dou·Y. T. Zhu·X. Zhang·G. Zhao·Zh. Wu·R. Chen
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Abstract

The high-contrast coronagraph for direct imaging earth-like exoplanet at the visible needs a contrast of 10^(-10) at a small angular separation of 4 lambda/D or less. Here we report our recent laboratory experiment that is close to the limits. The test of the high-contrast imaging coronagraph is based on our step-transmission apodized filter. To achieve the goal, we use a liquid crystal array (LCA) as a phase corrector to create a dark hole based on our dedicated focal dark algorithm. We have suppressed the diffracted and speckle noise near the star point image to a level of 1.68 x 10^(-9) at 4 lambda/D, which can be immediately used for the direct imaging of Jupiter like exoplanets. This demonstrates that high-contrast coronagraph telescope in space has the potentiality to detect and characterize earth-like planets.

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C. C. Liu, D. Q. Ren, J. P. Dou, Y. T. Zhu, X. Zhang, G. Zhao, Zh. Wu, R. Chen. 2014-06-09. A high-contrast coronagraph for earth-like exoplanet direct imaging: design and test. https://arxiv.org/abs/1406.2364

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