运用蒙特卡罗方法分析像增强器分辨率

Simulation of Image Intensifier Resolution in Monte Carlo Method

介绍了运用蒙特卡罗方法分析三代微光像增强器分辨率的方法。该方法取一组随机数,来模拟像管中光电阴极受激发射的电子。综合考虑微通道板参数、第一近贴距、第二近贴距、阴极电压和荧光屏电压等影响,模拟追踪电子的运动轨迹。并根据像面上电子的落点分布来计算调制传递函数,从而确定像管的分辨率。经比较,此方法计算简单、运行快速,模拟结果与实验值的偏差不超过5%,理论模型满足实际需求,可为三代微光像增强器的设计提供参考。

The resolution of the image intensifier was modeled and simulated in Monte Carlo method with the software package MATLAB. In the simulation, the electron emission from the photocathode was approximated with a set of random numbers. The impacts of the various factors, such as the specifications of the micro-channel plate, the 1st and 2^nd proximity distances, cathode voltage and phosphor screen voltage, on the electron trajectories were calculated. The resolution was derived from the modulation transfer function（MTF）, which was evaluated by the electron distribution on the image surface. The simulated and measured results were compared, and the discrepancy was found to be less than 5 %. We suggest that the resolution simulation may be of much technological interest in the design of the generation Ⅲ image intensifier.