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arXiv · 1910.00374

C-MORE : the laser guide star wavefront sensor

J. L. Gach·D. Boutolleau·A. Caillat·P. Feautrier·R. Pourcelot·E. Stadler
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Abstract

After releasing reference camera solutions in the visible and infrared for natural guide star wavefront sensing with unbeaten performance, we will present the first results of First Light Imaging s C-MORE, the first laser guide star oriented wavefront sensor camera. Within the Opticon WP2 european funded project (INFRAIA 2016-2017, Grant agreement n 730890), which has been set to develop LGS cameras, fast path solutions based on existing sensors had to be explored to provide working-proven cameras to ELT projects ready for the first light schedule. Result of this study, C-MORE is a CMOS based camera with 1600x1100 pixels (9um pitch) and 500 FPS refresh rate. It has been developed to answer most of the needs of future laser based adaptive optics systems (LGS) to be deployed on 20-40m-class telescopes as well as on smaller ones. Using a global shutter architecture, it won t introduce differential temporal errors on the wavefront reconstruction and simplifies the whole command loop. We present the global architecture of the camera, dimensions, weight, interfaces, its main features and measured performance in terms of noise, dark current, quantum efficiency and image quality which are the most important parameters for this application. Because of the very low cost of this solution, this camera can be used also in life-sciences and high end industrial applications, which was also an objective of the Opticon project.

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J. L. Gach, D. Boutolleau, A. Caillat, P. Feautrier, R. Pourcelot, E. Stadler. 2019-10-01. C-MORE : the laser guide star wavefront sensor. https://arxiv.org/abs/1910.00374

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