轴对称静场系统聚焦特性

Numerical simulation and analyses of axial symmetric electron optics focusing characteristics

建立了不等径双圆筒电极结构的旋转轴对称静电场电子光学聚焦系统模型,利用ANSYS软件,数值模拟了电子束在其内部场中的运动情况,给出了理论计算的像面和最佳成像位置。研究了电极形状、尺寸和负载电压等因素对系统成像特性的影响。得出了各电极负载对聚焦点位置影响的量化关系。研究表明:聚焦极对系统成像的影响比加速极和阳极大;聚焦极负载电压对成像特性的影响比电极尺寸和形状大得多。

An electron optics model of axial symmetric cylinder is adopted, three-dimensional and two-dimensional model are established based on this model. The traces of electron beam are calculated, and image location is also obtained. The influences Of the electrode shape, size and load on imaging are analyzed. The result indicates that the focusing electrode is more significant than the other electrodes, and load is the most critical parameter in the electron optics system.