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arXiv · 2412.10109

Large-format photodetecting system pCam6060 with a GSENSE6060BSI CMOS detector, developed at SAO RAS and optimized for photometric methods

Abstract

The pCam6060 photodetecting system was developed at SAO RAS and is based on the GSENSE6060BSI photodetector manufactured by GPixel (China) with a frame format of 6144x6144 active pixels and a pixel size of 10 mkm. The readout speed reached 11 fps. The back-illuminated detector has a wide spectral range of 200-1040 nm with a minimum quantum efficiency (QE) of 10% and maximum sensitivity of 95% at 580 nm. The quantum efficiency in the near-infrared range was 58% at 850 nm. The pCam6060 system controller implements a mode of simultaneous image readout via two 12-bit video channels with different gain and their subsequent combination in the controller into a single frame with an extended 16-bit dynamic range. This method simultaneously achieves a low readout noise level (about 3 e-) in the high-gain channel and a large dynamic range (full well capacity of about 100000 e-) in the low-gain channel. Back-illuminated CMOS detectors, unlike front-illuminated devices, do not have the effect of long-term preserving the residual charge from previous exposures, which makes them suitable for recording faint objects in photometric long-exposure observation methods. Communication between the host computer and the camera was carried out via a fiber optic line at distances of up to 50 m. Video data are recorded on the computer hard drive in real-time. The pCam6060 photodetecting system is designed for astronomical applications and has a moisture-proof design.

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I. Afanasieva, V. Murzin, V. Ardilanov, N. Ivaschenko, M. Pritychenko. 2024-12-13. Large-format photodetecting system pCam6060 with a GSENSE6060BSI CMOS detector, developed at SAO RAS and optimized for photometric methods. https://arxiv.org/abs/2412.10109

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