摘要
本文提出一个双光阑电子透镜的通用数学模型,它具有a和b两个特征参数,参数b是调整透镜不对称程度的,而参数a则可控制透镜中的电位分布.当b等于零时,它简化为文献[1]提出的数学模型,而当a、b同时为零时,则简化为众所周知的Bulter型.本文还依此数学模型中参数a、b的取值,讨论了透镜的像差特性和焦点特性.
A general mathematical model of the electron lens composed of two apertures is presented in this paper. There are two parameters in this model. By changing the value of the parameter b, the asymmetrical level of the equipotential surfaces between the two apertures used as the first anode and the second anode can be transformed. And on the other hand, by changing the value of the parameter a, the distribution of the intensity of the electrical field can be transformed. After discussing the electronopticalproperties of the lens some conclusions are given finally.
关键词
电子光学
电子透镜
球面像差
electron-optics
electron lens
spherical aberration
