基于CMOS图像传感器的复合型中子照相电子学系统的研制

Development of Neutron Imaging Electronics System Based on CMOS Image Sensor

针对高能物理实验中高通量、高性能的中子探测需求,本文提出了一种基于CMOS图像传感器的复合型中子照相电子学系统。该系统采用Kintex-7系列的FPGA作为系统逻辑处理的核心器件,利用SiPM的快响应为CMOS图像传感器提供快门触发,使其对光纤光锥投影的中子光斑进行曝光。通过SiPM提供的粗位置信息确定CMOS传感器的感兴趣区域,读出数据传输至上位机进行显示与分析。实验结果表明,该系统中最小像素单元尺寸为28μm×28μm的CMOS传感器能够对孔径为200μm的小孔进行成像,最大偏移为28μm,系统最高计数率为82 kHz,可实现高效率的中子探测。

For the demand of high-throughput and high-performance neutron detection in high-energy physics experiments,a composite neutron imaging electronics system based on CMOS image sensor is proposed in this paper.The system adopts Kintex-7 series FPGA as the core device for system logic processing,and it utilizes the fast response of SiPM to provide shutter triggering for the CMOS image sensor to expose the neutron spot projected by the fiber optical taper.The coarse position information provided by the SiPM is to determine the region of interest of CMOS sensor for readout,and the readout data is transferred to the host computer for display and analysis.The results revealed that the CMOS sensor with the smallest pixel unit size of 28μm×28μm in the system is capable of imaging holes with an aperture diameter of 200μm,with a maximum imaging offset of 28μm and a maximum count rate of 82 kHz,which enables high-efficiency neutron detection.