Abstract

One of the major challenges faced by externally occulted solar coronagraphs is the suppression of the light diffracted by the occulter edge. It is a contribution to the stray light that overwhelms the coronal signal on the focal plane and must be reduced by modifying the geometrical shape of the occulter. There is a rich literature, mostly experimental, on the appropriate choice of the most suitable shape. The problem arises when huge coronagraphs, such as those in formation flight, shall be tested in a laboratory. A recent contribution [Opt. Lett. 41, 757 (2016) [CrossRef]  ] provides the guidelines for scaling the geometry and replicate in the laboratory the flight diffraction pattern as produced by the whole solar disk and a flight occulter but leaves the conclusion on the occulter scale law somehow unjustified. This paper provides the numerical support for validating that conclusion and presents the first-ever simulation of the diffraction behind an occulter with an optimized shape along the optical axis with the solar disk as a source. This paper, together with Opt. Lett. 41, 757 (2016) [CrossRef]  , aims at constituting a complete guide for scaling the coronagraphs’ geometry.

© 2017 Optical Society of America

Scaled-model guidelines for formation-flying solar coronagraph missions

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Opt. Lett. 41(4) 757-760 (2016)

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Appl. Opt. 50(36) 6632-6644 (2011)

Effective optical constants of anisotropic silver nanoparticle films with plasmonic properties: erratum

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Octave-spanning supercontinuum generation in a silicon-rich nitride waveguide: erratum

Xing Liu, Minhao Pu, Binbin Zhou, Clemens J. Krückel, Attila Fülöp, Victor Torres-Company, and Morten Bache
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