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Recently, silicon photomultipliers (SiPMs) have been used in several space-borne missions, owing to their solid state, compact size, low operating voltage, and insensitivity to magnetic fields. However, operating SiPMs in space results in radiation damage and degraded performance. In-orbit quantitative studies on these effects are limited. In this study, we present in-orbit SiPM characterization results obtained by the second detector of the Gamma-Ray Integrated Detectors (GRID-02), which was launched on 6 November 2020. An increase in dark current of $\sim$100 $\mu$A/year per SiPM chip (model MicroFJ-60035-TSV) at 28.5 V and 5 $^{\circ}$C was observed. Consequently, the overall noise level (sigma) of the GRID-02 detector increased by $\sim$7.5 keV/year. The estimate of this increase is $\sim$40 $\mu$A/year per SiPM chip at -20 $^{\circ}$C, highlighting the positive effect of using a cooling system., Comment: final manuscript, 20 pages, 8 figures, published on NIM-A

The imaging quality detection of CMOS digital image sensor is a key link of the manufacturing process of camera. Through USB2.0 interface, transmit the digital image video stream of CMOS sensor to the PC and intercept a frame image data from the video stream; detect the MTF, brightness and defect of CMOS camera imaging and know the performance of the camera after analysis. It has been tested that this system can measure the imaging performances of all the CMOS cameras less than 3 million pixels accurately.