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arXiv · 1103.1909

Improved High Contrast Imaging with On-Axis Telescopes using a Multi-Stage Vortex Coronagraph

Dimitri Mawet·Eugene Serabyn·J. Kent Wallace·Laurent Pueyo
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Abstract

The vortex coronagraph is one of the most promising coronagraphs for high contrast imaging because of its simplicity, small inner working angle, high throughput, and clear off-axis discovery space. However, as with most coronagraphs, centrally-obscured on-axis telescopes degrade contrast. Based on the remarkable ability of vortex coronagraphs to move light between the interior and exterior of pupils, we propose a method, based on multiple vortices, that, without sacrificing throughput, reduces the residual light leakage to (a/A)^n, with n >=4, and a and A being the radii of the central obscuration and primary mirror, respectively. This method thus enables high contrasts to be reached even with an on-axis telescope.

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Dimitri Mawet, Eugene Serabyn, J. Kent Wallace, Laurent Pueyo. 2011-03-09. Improved High Contrast Imaging with On-Axis Telescopes using a Multi-Stage Vortex Coronagraph. https://doi.org/10.1364/ol.36.001506

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