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arXiv · 2208.00377

Last performances improvement of the C-RED One camera using the 320x256 e-APD infrared Saphira detector

Abstract

We present here the latest results obtained with the C-RED One camera developed by First Light Imaging for fast ultra-low noise infrared applications. This camera uses the Leonardo Saphira e-APD 320x256 infrared sensor in an autonomous cryogenic environment with a low vibration pulse tube and with embedded readout electronics system. Some recent improvements were made to the camera. The first important one concerns the total noise of the camera. Limited to 1.75 microns wavelength cut-off with proper cold filters, looking at a blackbody at room temperature and f/4 beam aperture, we now measure total noise down to 0.6 e at gain 50 in CDS mode 1720 FPS, dividing previous noise figure by a factor 2. The total camera background of 30-400 e/s is now achieved with a factor 3 of background reduction, the camera also looking at a room temperature blackbody with an F/4 beam aperture. Image bias oscillations, due to electronics grounding scheme, were carefully analyzed and removed. Focal plane detector vibrations transmitted by the pulse tube cooling machine were also analyzed, damped and measured down to 0.3 microns RMS, reducing focal plane vibrations by a factor 3. In addition, a vacuum getter of higher capacity is now used to offer camera operation without camera pumping during months. The camera main characteristics are detailed: pulse tube cooling at 80K with limited vibrations, permanent vacuum solution, ultra-low latency Cameralink full data interface, safety management of the camera by firmware, online firmware update, ambient liquid cooling and reduced weight of 20 kg.

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Philippe Feautrier, Jean-Luc Gach. 2022-07-31. Last performances improvement of the C-RED One camera using the 320x256 e-APD infrared Saphira detector. https://arxiv.org/abs/2208.00377

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