【作者】 崔东旭；

【导师】 常本康；

【作者基本信息】 南京理工大学 ， 电子科学与技术， 2013， 博士

【摘要】 三代微光像增强器是构成先进微光夜视技术的核心器件,信噪比是微光像增强器的重要综合指标之一,本文围绕三代微光像增强器的信噪比测试技术、类针孔光源弱光照度测量和噪声特性分析中存在的问题,开展了一系列的研究工作。本文首先研究了微光像增强器信噪比的测试原理和方法,以国军标为信噪比测试依据,对三代微光像增强器信噪比校准装置的硬件和软件分别进行设计和研制,包括总体结构、光源装置、光电检测组件、信号处理器、数据采集系统、分析软件模块和数据库存储模块等,建立了国内首台三代微光像增强器的信噪比校准装置,解决了国内微光像增强器信噪比测量量值统一和准确可靠问题。研究了类针孔弱光光斑的光子统计特性及光子通量测量原理,基于光子计数测量方法研制类针孔微弱光照度计,首次实现了直径为0.2mm,照度为1.08×10-41x微光像增强器信噪比测试光源的照度直接测量,解决了由于微光像增强器信噪比测试光源照度的间接传递测量导致微光像增强器信噪比的测试无法闭环问题。提出了MCP输出信噪比的概念和具体的测试方法,利用MCP噪声特性测试系统进行了MCP输出信噪比测试实验,为MCP噪声评价提供了新的技术途径；对微光像增强器中光阴极、MCP和荧光屏等各部件对整管信噪比产生影响进行理论分析,开展了微光像增强器信噪比链的验证试验,为进一步降低微光像增强器的噪声提供了理论依据和实验支撑。在微光像增强器信噪比校准装置的基础上,利用低噪声高分辨率CCD,自行研制了halo效应测试仪,对超二代微光像增强器和三代微光像增强器的halo效应进行了测试分析。在低照度光源照射下,分别采集了一定直径的小孔像以及该小孔在不同微光像增强器荧光屏上的像,分析了小孔在微光像增强器荧光屏上形成halo图像的组成成分以及影响因素,并与美国三代微光像增强器halo效应值进行了比对,验证了我们测量的准确性。通过开展微光像增强器halo效应的测量研究,进一步推动了微光像增强器制管工艺的改进,并为微光像增强器性能评价提供了新的测试手段。更多还原

【Abstract】 The third generation low-light-level (LLL) image intensifier is the core device of the advanced night vision technology. The signal to noise ratio (SNR) is one of important composite indicators of the image intensifier. To solve the problems of SNR measurement technology, pinhole-like low light illuminancy measurement and noise characteristics analysis, this paper has developed a series of researches.Firstly, we studied the principles and methods of image intensifier SNR testing in this article. With the SNR testing national army standards as technical standards, we designed and developed the hardware and software for the SNR correction device of the third generation low-light-level image intensifier, which consisted of the overall structure, light source device, photoelectric detection components, signal processor, data acquisition system, analyzing software module, database storage module, etc. We established the first internal SNR correction device of the third generation low-light-level image intensifier and resolved the problems of value uniformity and accuracy in SNR measurement of internal low-light-level image intensifier.Secondly, we also studied the photon statistical characteristics of pinhole-like low light spot and measurement principle of photon flux. Based on photon counting measurement method, we developed pinhole-like low light luminometer and implemented the direct measurement of illuminancy of the low-light-level image intensifier SNR testing with a0.2mm diameter and a1.08x10-4lx illuminancy for the first time. And we solved the problem that the SNR testing can’t be closed-loop, which is caused by the illuminancy indirect transfer of the SNR testing lamp-house for the LLL image intensifier.Moreover, we presented the concepts and the specific testing methods of the microchannel plate (MCP) output SNR, and did the MCP output SNR testing experiments by using MCP noise characteristic measurement system, which provided the new technical approach for MCP noise characteristic evaluation. We also analyzed the effect to the LLL image intensifier SNR, which is caused by the photocathode, MCP and phosphor screen. Furthermore, we did the verification experiments for the SNR chain of the LLL image intensifier, which provided the theoretical basis and experimental support for further decreasing the noise of the LLL image intensifier.Based on the SNR correction device of LLL image intensifier, we developed the halo effect tester by using the high-resolution CCD, and performed the test analysis on halo effect of the super second and the third generation LLL image intensifiers. Under irradiation with low illuminancy lamp-house, we respectively collected the pinhole image with a certain diameter and the image of the pinhole on the different image intensifier phosphor screen, and analyzed the compositions and impact factors of the halo image of the phosphor screen. And we testify the accuracy of the measurements by comparing with the halo value of the American third generation LLL image intensifier. The study of the halo effect measurement would further motivate the improvement of tube-making process, and provide the new testing methods for the performance evaluation of the LLL image intensifier.更多还原