电荷云尺寸对紫外光子计数成像探测器性能的影响

微通道板出射电荷云尺寸与微通道板增益、微通道板输出面和楔条形阳极间距离以及阳极加速电压等因素有关.到达阳极的电荷云尺寸对紫外光子计数探测器的成像性能有重要影响.本文研究了电荷云尺寸对紫外光子计数成像系统成像性能的影响,论述了调制畸变和"S"畸变两种图像畸变及其产生的原因,采用蒙特卡洛方法模拟了不同尺寸的电荷云对阳极解码的影响.实验测试了微通道板和阳极间距离、微通道板增益以及阳极加速电压对紫外光子计数成像系统成像性能的影响,并给出了实际解决调制畸变和"S"畸变的有效方法. 关键词： 光子计数成像 楔条形阳极 微通道板 阳极探测器

Influence of charge cloud size on performance of UV photon-counting imaging detector

The size of charge cloud is examined as a function of acceleration voltage, distance between MCP and anode, and MCP gain. The performance of photon counting imaging detector is significantly affected by charge cloud size. In this paper, the influence of charge cloud size on the performance of UV photon-counting imaging systems is investigated. Modulation distortion, "S" distortion and their cause are discussed. Then, Monte Carlo simulations for anode decode with different charge cloud sizes are carried out. And finally, the effects of acceleration voltage, distance between MCP and WSA, and MCP gain on the system performance are tested and some practical solutions of modulation and "S" distortion are suggested.