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Eighth-Order Image Masks for Terrestrial Planet Finding

Marc J. Kuchner·Justin Crepp·Jian Ge
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Abstract

We describe a new series of band-limited image masks for coronagraphy that are insensitive to pointing errors and other low-spatial-frequency optical aberrations. For a modest cost in throughput, these ``eighth-order'' masks would allow the Terrestrial Planet Finder Coronagraph (TPF-C) to operate with a pointing accuracy no better than that of the Hubble Space Telescope. We also provide eighth-order notch filter masks that offer the same robustness to pointing errors combined with more manageable construction tolerances: binary masks and graded masks with moderate optical density requirements.

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Marc J. Kuchner, Justin Crepp, Jian Ge. 2005-05-02. Eighth-Order Image Masks for Terrestrial Planet Finding. https://doi.org/10.1086/430200

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