Failure analysis and reliability assessment of infrared thermal imager

In this paper, FMECA is used to analyze the equipment system of infrared thermal imager given the characteristics of refrigeration temperature fluctuation and limited infrared video acquisition in long-term service. The results show that the imaging circuit component failure is the major fault mode in the infrared thermal imager equipment system, and the influence of the fault is mostly the abnormal refrigeration temperature. The degradation models of vacuum dewar performance index, refrigerator performance index, and Blind pixel rate index were established respectively. Copula function is used to analyze the influence of correlation degree between multiple performance indicators on reliability assessment. The DIC criterion is used to compare the ratio of three Copula models and select the most appropriate correlation degradation model. The variation rule of reliability difference between the independent model and related model is obtained, which guides equipment maintenance at different stages.