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arXiv · 1510.03796

A Transmission-Filter Coronagraph: Design and Test

Deqing Ren·Jiangpei Dou·Yongtian Zhu
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Abstract

We propose a transmission-filter coronagraph for direct imaging of Jupiter-like exoplanets with ground-based telescopes. The coronagraph is based on a transmission filter that consists of finite number of transmission steps. A discrete optimization algorithm is proposed for the design of the transmission filter that is optimized for ground-based telescopes with central obstructions and spider structures.We discussed the algorithm that is applied for our coronagraph design. To demonstrate the performance of the coronagraph, a filter was manufactured and laboratory tests were conducted. The test results show that the coronagraph can achieve a high contrast of 10 to -6.5 at an inner working angle of 5λ/D, which indicates that our coronagraph can be immediately used for the direct imaging of Jupiter-like exoplanets with ground-based telescopes.

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Deqing Ren, Jiangpei Dou, Yongtian Zhu. 2015-10-13. A Transmission-Filter Coronagraph: Design and Test. https://doi.org/10.1086/652958

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