基于夜天光光谱匹配的微光像增强器信噪比研究  

Research on Signal-to-noise Ratio of Low-light Level Image Intensifier Based on Night Sky Light Spectrum Matching

作　　者：张琴 拜晓锋 程宏昌 焦岗成 李周奎 韩坤 李琦 ZHANG Qin;BAI Xiaofeng;CHENG Hongchang;JIAO Gangcheng;LI Zhoukui;HAN Kun;LI Qi(Key Laboratory of Science and Technology on Low-Level-Light Night Vision,Xi'an 710065,China;Kunming Institute of Physics,Kunming 650223,China)

机构地区：[1]微光夜视技术重点实验室,西安710065 [2]昆明物理研究所,昆明650223

出　　处：《光子学报》2022年第3期165-173,共9页Acta Photonica Sinica

基　　金：微光夜视技术重点实验室基金(No.J20190102)。

摘　　要：针对现有微光像增强器的信噪比实验室测试结果无法准确描述其在实际夜天辐射条件下工作时信噪比的问题,依据光阴极与夜天光光谱匹配关系和光量子噪声起伏理论推导了微光像增强器的输出信噪比理论计算模型。在基于典型微光像增强器参数对模型验证的基础上,计算了典型超二代和三代像增强器在实际夜天辐射条件下工作时的信噪比。结果表明,实际夜天辐射条件下的信噪比与实验室A光源测试条件下的信噪比存在较大差异,且超二代和三代像增强器的信噪比在实际夜天辐射条件下显示出相较实验室测量时更大的差异性。本研究可为实际夜天辐射工作条件下的微光像增强器信噪比评价提供一种可用途径。As an important performance index of the low-light-level image intensifiers,the signal-to-noise ratio can determine the detection limit under the low-light conditions.Therefore,an accurate evaluation of the signal-to-noise ratio is helpful to grasp actual working status of the low-light-level image intensifiers.In the photoelectric image transmission process,the quantum noise of the photocathode,the particle noise of the microchannel plate and the phosphor screen will add noise to the transmission chain of the image,thereby reducing the signal-to-noise ratio of the image.Laboratory testing methods for the signal-to-noise ratio of the low-light-level image intensifiers are relatively mature,and the photomultiplier tube is usually used as the core detection device to detect the signal and noise of the output light spot image.The test light source specified in the laboratory test of the signal-to-noise ratio is 2856 K light source A.Due to the difference of spectral distribution between the night sky light and the light source A,the laboratory measurement results of the signal-to-noise ratio cannot accurately describe the signal-to-noise ratio of the low-light-level image intensifier under actual night sky light conditions,and the actual night sky light spectrum distribution is relatively complicated,which is difficult to be simulated by the laboratory test light source.In response to this problem,the theoretical calculation model of the output signal-to-noise ratio of the low-light-level image intensifier is deduced based on the photocathode and night light spectrum matching relationship and the theory of light quantum noise fluctuation.After verifying the model based on the parameters of the typical low-light image intensifier,the output signal-to-noise of the two under the radiation of three kinds of night sky light and test light source with the same illuminance is calculated based on the model.The comparative analysis results show that:1)Under the radiation of three kinds of night sky light,the actual signal-to

关 键 词：微光像增强器 夜天辐射 光谱匹配 信噪比 A光源 

分 类 号：TN223[电子电信—物理电子学]