基于瑞利判据的分幅相机空间调制传递函数

Spatial modulation transfer function of framing camera using Rayleigh criterion

摘要:

根据脉冲展宽分幅相机原理和瑞利判据思想，通过建立研究模型、模拟磁场分布、追踪电子轨迹和成像分布直方图统计及其高斯拟合，采用瑞利判据计算脉冲展宽分幅相机轴上空间分辨力和成像调制度。研究结果显示，基于瑞利判据通过相邻物点成像分布计算脉冲展宽分幅相机空间调制传递函数是可行的，当阴极轴上相邻物点分别发射10 000个电子时，两物点完全分辨的成像调制度为98.573 2%，空间分辨力为194.523 7 μm；恰能分辨的调制度为19.16%，空间分辨力为73.22 μm；不能分辨的成像调制度为0.14%，空间分辨力为4.57 μm。研究结论为二维超快诊断设备空间调制传递函数的计算提供了一种直观的解决方法。

Abstract:

The working principle of pulse-dilation framing camera and Rayleigh criterion are introduced. The spatial resolution and modulation on-axis of pulse-dilation framing camera are calculated by using Rayleigh criterion through building model, simulating magnetic field, tracking electron trajectory and fitting histogram of imaging distribution. The research results show that, when the 10 000 electrons are emitted from adjacent object points on the photocathode, the imaging modulation of two fully distinguishable adjacent object points is 98.5732%, the spatial resolution is 194.523 7 μm; the modulation of just distinguishable is 19.16%, the spatial resolution is 73.22 μm; the modulation of undistinguishable is 0.14%, the spatial resolution is 4.7 μm. This work can provide a visualized solution for calculating spatial modulation transfer function of 2D ultrafast diagnosis device.