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arXiv · 2102.03201

SLM-based Active Focal-Plane Coronagraphy: Status and future on-sky prospects

Jonas G. Kühn·Laurent Jolissaint·Audrey Bouxin·Polychronis Patapis
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Abstract

We recently started to investigate how liquid-crystal on silicon (LCOS) spatial light modulator (SLM) would perform as programmable focal-plane phase mask (FPM) coronagraphs. Such "adaptive coronagraphs" could potentially help adapt to observing conditions, but also tackle specific science cases (e.g. binary stars). Active FPMs may play a role in the context of segmented telescope pupils, or to implement synchronous coherent differential imaging (CDI). We present a status update on this work, notably early broadband contrast performance results using our new Swiss Wideband Active Testbed for High-contrast imaging (SWATCHi) facility. Finally, we unveil the upcoming near-infrared PLACID instrument, the Programmable Liquid-crystal Adaptive Coronagraphic Imager for the 4-m DAG observatory in Turkey, with a first light planned for the end of the year 2022.

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Jonas G. Kühn, Laurent Jolissaint, Audrey Bouxin, Polychronis Patapis. 2021-02-05. SLM-based Active Focal-Plane Coronagraphy: Status and future on-sky prospects. https://doi.org/10.1117/12.2562579

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