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arXiv · 2406.18660

Optical modeling for the evaluation of HOWFSC on embedded processors

Kian Milani·Ewan Douglas·Leonid Pogorelyuk·Christopher Mendillo·Kerri Cahoy·Nicholas Belsten·Brandon Eickert·Shanti Rao
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Abstract

The correction of quasi-static wavefront errors within a coronagraphic optical system will be a key challenge to overcome in order to directly image exoplanets in reflected light. These quasi-static errors are caused by mid to high-order surface errors on the optical elements as a result of manufacturing processes. Using high-order wavefront sensing and control (HOWFSC) techniques that do not introduce non-common path aberrations, the quasi-static errors can be corrected within the desired region of interest designated as the dark hole. For the future Habitable Worlds Observatory (HWO), HOWFSC algorithms will be key to attaining the desired contrasts. To simulate the performance of HOWFSC with space rated processors, optical models for a 6 m class space-borne observatory and a coronagraph have been developed. Phenomena such as the Talbot effect and beamwalk are included in the simulations using combinations of ray-based modeling and end-to-end propagation techniques. After integrating the optical models with the embedded processors, simulations with realistic computation times can be performed to understand the computational hardware performance that will be needed to maintain the desired contrasts. Here, the details of the optical models are presented along with the HOWFSC methods utilized. Initial results of the HOWFSC methods are also included as a demonstration of how system drifts will degrade the contrast and require dark hole maintenance.

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Kian Milani, Ewan Douglas, Leonid Pogorelyuk, Christopher Mendillo, Kerri Cahoy, Nicholas Belsten, Brandon Eickert, Shanti Rao. 2024-06-26. Optical modeling for the evaluation of HOWFSC on embedded processors. https://arxiv.org/abs/2406.18660

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