1. Prototyping liquid-crystal coronagraphs for exo-Earth imaging
- Author
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Laginja, Iva, Doelman, David, Snik, Frans, Baudoz, Pierre, Bettonvil, Felix, Rietjens, Jeroen H., van Dijk, Chris N., Peeters, Kristien, Eigenraam, Alexander, Pougheon, Erin, van der Wielen, Tom, Esposito, Marco, Wijnen, Thomas, Krasteva, Mariya, and Taccola, Matteo
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
This paper presents initial results from the ESA-funded ``SUPPPPRESS'' project, which aims to develop high-performance liquid-crystal coronagraphs for direct imaging of Earth-like exoplanets in reflected light. The project focuses on addressing the significant challenge of polarization leakage in vector vortex coronagraphs (VVCs). We utilize newly manufactured multi-grating, liquid-crystal VVCs, consisting of a two- or three-element stack of vortex and grating patterns, to reduce this leakage to the $10^{-10}$ contrast level. We detail the experimental setups, including calibration techniques with polarization microscopes and Mueller matrix ellipsometers to enhance the direct-write accuracy of the liquid-crystal patterns. The performance testing of these coronagraph masks will be conducted on the THD2 high-contrast imaging testbed in Paris., Comment: 14 pages, 10 figures
- Published
- 2024