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arXiv · astro-ph/0209271

Notch Filter Masks: Practical Image Masks for Planet-Finding Coronagraphs

Marc J. Kuchner·David N. Spergel
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Abstract

An ideal coronagraph with a band-limited image mask can efficiently image off-axis sources while removing identically all of the light from an on-axis source. However, strict mask construction tolerances limit the utility of this technique for directly imaging extrasolar terrestrial planets. We present a variation on the basic band-limited mask design--a family of ``notch filter'' masks--that mitigates this problem. These robust and trivially achromatic masks can be easily manufactured by cutting holes in opaque material.

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Marc J. Kuchner, David N. Spergel. 2003-04-22. Notch Filter Masks: Practical Image Masks for Planet-Finding Coronagraphs. https://doi.org/10.1086/375836

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