Broadband patterned liquid crystal coronagraphs for space-based high-contrast imaging of exoplanets

International Conference on Space Optics (ICSO), pp. 92

Abstract

Coronagraphs based on patterned liquid crystal technology are promising high performance broadband components for application in space-based high-contrast imaging instruments. In this paper, the design, manufacturing and application of such coronagraphs are discussed in the context of the ESA-funded “SUPPPPRESS” project. This project 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 discuss the paths taken to optimize the performance of coronagraph in terms of enhancing the pattern writing accuracy and reducing the deviation from half-wave retardance over a broad spectral range. In addition, we describe preliminary characterization results obtained with test patterns using a far-field test setup, and will discuss the performance testing of coronagraph masks on the THD2 high-contrast imaging testbed in Paris.

Authors 10

1. David S. Doelman Aachen SRON Netherlands Institute for Space Research

   Space Research Organisation Netherlands

   Affiliation as printed

   SRON Netherlands Institute for Space Research (Netherlands)

2. Frans Snik Aachen Leiden Univ. (Netherlands)

   Leiden University

   Affiliation as printed

   Leiden Univ. (Netherlands)

   NOVA (Netherlands)

3. Jeroen H. H. Rietjens Aachen SRON Netherlands Institute for Space Research

   Space Research Organisation Netherlands

   Affiliation as printed

   SRON Netherlands Institute for Space Research (Netherlands)

4. Iva Laginja Aachen Leiden Univ. (Netherlands)

   Leiden University · Centre National de la Recherche Scientifique · Université Paris Cité · Observatoire de Paris · Laboratoire d’études spatiales et d’instrumentation en astrophysique

   Affiliation as printed

   LESIA, Observatoire de Paris, Univ. PSL, Sorbonne Univ., Univ. Paris Cité, CNRS (France)

   Leiden Univ. (Netherlands)

   NOVA (Netherlands)

5. Pierre Baudoz

   Centre National de la Recherche Scientifique · Université Paris Cité · Observatoire de Paris · Laboratoire d’études spatiales et d’instrumentation en astrophysique

   Affiliation as printed

   LESIA, Observatoire de Paris, Univ. PSL, Sorbonne Univ., Univ. Paris Cité, CNRS (France)

6. Alexander B. C. Eigenraam Aachen SRON Netherlands Institute for Space Research

   Space Research Organisation Netherlands

   Affiliation as printed

   SRON Netherlands Institute for Space Research (Netherlands)

7. Mario Vretenar Aachen SRON Netherlands Institute for Space Research

   Space Research Organisation Netherlands

   Affiliation as printed

   SRON Netherlands Institute for Space Research (Netherlands)

8. Kristien Peeters Aachen cosine Remote Sensing B.V

   Cosine (Netherlands)

   Affiliation as printed

   cosine Remote Sensing B.V. (Netherlands)

9. Rico Landman
10. Felix C. M. Bettonvil Aachen Leiden Univ. (Netherlands)

    Leiden University

    Affiliation as printed

    Leiden Univ. (Netherlands)

    NOVA (Netherlands)