Design of sCMOS Refrigerated Imaging System for High-altitude Research Telescopes

To meet the needs of low-light detection with large field-of-view astronomical telescopes in high-altitude areas in our country, this study utilized a high-performance scientific CMOS (sCMOS) detector, GSENSE1516BSI, from Chang Guang Satellite Technology Co., Ltd. The imaging system, which is controlled by a Xilinx Kintex-7 FPGA, was designed to be low-noise, highly sensitive, and to utilize thermoelectric cooling (TEC) technology for active cooling. The hardware components encompass the peripheral circuitry of the sCMOS detector, FPGA readout circuit, and TEC active cooling module. The software includes a timing control module, a data alignment and reception training module, and a DDR3 high-speed cache module. In addition, a large-array pixel data DDR3 read-write validation module was developed to validate the reliability of storing large-array pixel data in the DDR3 submodule during the design phase. This early validation helped identify potential data transmission issues, thereby optimizing the system testing approach. Ultimately, comprehensive testing confirmed the stable performance of the designed sCMOS imaging system with a readout noise of 4.33e^－ and a cooling temperature of -30℃; the dark current at -30℃ is 0.15 e^－/pixel/s. It can stably read 4 k×4 k large array pixel data, satisfying the astronomical observation requirements of large-field telescopes.