利用Monte Carlo方法、有限元法和有限差分法建立了时间展宽X射线分幅相机的理论模型, 对相机静态空间分辨特性进行了理论研究。当光电阴极的电压为-3 kV, 采用三个磁透镜, 成像倍率为21时, 相机的静态空间分辨率优于110 μm.研究了空间分辨率与发射位置、阴极电压、磁聚焦透镜数量的关系.模拟结果表明, 发射位置离中心越近, 阴极电压越高, 磁聚焦透镜个数越多, 空间分辨率越好.此外, 平面的光电阴极经磁聚焦透镜成像后, 像面不是一个平面而是一个曲面.

The spatial resolution of the time dilation X-ray framing camera is simulated by using the Monte Carlo method, the finite element method and the finite difference method. While DC bias on the photo-cathode is -3 kV and three large aperture magnetic lens are used to image the electrons from the photo-cathode onto the microchannel plate with the image ratio of 21, the theoretical static spatial resolution is better than 110 μm. The relationship between the spatial resolution and the point of electron emitted from the photo-cathode is obtained. While the distance of the electron emitting point to the center of the photo-cathode is increased, the spatial resolution is worse. The variation of the spatial resolution with the photo-cathode voltage is provided. The spatial resolution is improved with increasing photo-cathode voltage. In addition, the spatial resolution is better by increasing the numbers of the magnetic lens. Furthermore, it can be seen from the simulation results that the image plane is a curved surface while the photo-cathode is a plane.