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arXiv · 2608.24526

Cassiopee: Defining the next-generation deformable mirror and high-speed SWIR camera for adaptive optics applications

Abstract

Future adaptive optics (AO) systems for astronomy, optical communications, space situational awareness, and laser-based defense require a new generation of components operating at unprecedented speed, sensitivity, and precision. We present a systematic approach to defining the specifications of two key technologies: a large-format, high-cadence SWIR camera and a high-order deformable mirror (DM). Starting from four representative use-cases, high-contrast exoplanet imaging, free-space optical communications, satellite observation, and laser focusing, we derive detailed AO error budgets to identify the dominant performance drivers. This analysis defines quantitative requirements for the DM (actuator count, stroke, bandwidth, electronics) and the camera (read noise, quantum efficiency, frame rate, latency, and dark current), developed in close collaboration with industrial partners. We then describe an integrated experimental testbed designed to validate both components in a closed AO loop under atmospheric and system-level disturbances representative of astronomical and telecom applications. Finally, we outline the roadmap toward on-sky validation with EKARUS, the new AO facility at Asiago Observatory, bridging the gap between component qualification and deployment in future extremely large telescopes and ground-to-space optical links.

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B. Neichel, T. Fusco, F. Oyarzun, V. Chambouleyron, J. -F. Sauvage, C. -T. Héritier, J. Charton, C. Pravert, F. Clop, L. Maillet, M. Laslandes, J. -L. Gach, D. Boutolleau, P. Feautrier, P. Bruno, Y. Wanwanscappel, C. Bremond. 2026-07-30. Cassiopee: Defining the next-generation deformable mirror and high-speed SWIR camera for adaptive optics applications. https://arxiv.org/abs/2608.24526

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