基于Vernier阳极微通道板光子计数探测器分割噪声

The Partition Noise Research of MCP Photon Counting Imager Detector Based on Vernier Anode

为消除微通道板光子计数探测器系统中电子噪声的干扰,研究了探测器分割噪声的来源,并提出利用COMSOL软件仿真计算分割噪声的方法.利用有限元方法对基于Vernier阳极探测器的成像过程进行三维建模,实现了一组5×5针孔阵列的模拟成像,计算出Vernier阳极分割噪声所产生的电子云质心位置的偏移量,验证了Vernier阳极探测器成像编码的正确性与仿真研究分割噪声的可行性.通过分析不同参量的阳极面板,利用数值拟合方法,得到电子云质心偏移量与阳极面板设计参量之间的关系.在固定面板参量的前提下,可以通过提高微通道板增益来有效降低分割噪声对质心位置偏移影响.

To get rid of the interference of electronic noise in the micro channel plate photon counting imager detector,the theory of partition noise was studied and the finite element method of calculating partition noise by COMSOL software was proposed.The three dimensional model of imaging principle based on the Vernier anode detector was built,the image of a set of pinhole array was simulated,and the centroid position offsets caused by the partition noise were calculated,which certifies the correctness of the position decoding algorithm and proves the feasibility of calculating partition noise.By adjusting the designed parameters of the Vernier anode,the influences of the partition noise on the centroid position offset of charge cloud were investigated.It is an effective way to reduce the partition noise by increasing the gains of micro-channel plates.