非制冷IRFPA的改进NETD评价方法

Noise Equivalent Temperature Difference(NETD) is an important technical indicator for evaluating the performance of uncooled infrared FPA(IRFPA). The paper introduces current measurement and calculation methods of NETD. It is found that only the temporal noise of IRFPA is considered in this method, and it does not involve the factor of spatial noise. Based on the analysis of the mechanism of uncooled IRFPA spatial noise generation, an improved NETD evaluation method is proposed. The method uses a comprehensive NETD indicator including temporal noise and spatial noise to evaluate IRFPA performance. Hundreds of a certain model uncooled IRFPAs are tested for noise calculating and spatial noise accounts for 31.8% of total noise energy, which proves that the influence of spatial noise on total noise cannot be ignored. Incorporating spatial noise into the NETD evaluation method of uncooled IRFPA can comprehensively and objectively evaluate the true performance of IRFPA, which has important engineering practical significance.