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arXiv · 1808.00589

SLM-based Digital Adaptive Coronagraphy: Current Status and Capabilities

Jonas Kuhn·Polychronis Patapis·Xin Lu·Marcel Arikan
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Abstract

Active coronagraphy is deemed to play a key role for the next generation of high-contrast instruments, notably in order to deal with large segmented mirrors that might exhibit time-dependent pupil merit function, caused by missing or defective segments. To this purpose, we recently introduced a new technological framework called digital adaptive coronagraphy (DAC), making use of liquid-crystal spatial light modulators (SLMs) display panels operating as active focal-plane phase mask coronagraphs. Here, we first review the latest contrast performance, measured in laboratory conditions with monochromatic visible light, and describe a few potential pathways to improve SLM coronagraphic nulling in the future. We then unveil a few unique capabilities of SLM-based DAC that were recently, or are currently in the process of being, demonstrated in our laboratory, including NCPA wavefront sensing, aperture-matched adaptive phase masks, coronagraphic nulling of multiple star systems, and coherent differential imaging (CDI).

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Jonas Kuhn, Polychronis Patapis, Xin Lu, Marcel Arikan. 2018-08-01. SLM-based Digital Adaptive Coronagraphy: Current Status and Capabilities. https://arxiv.org/abs/1808.00589

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