复合静电2磁浸没透镜的宽束曲轴聚焦性质及像差理论.PDF

第 22 卷 　第 1 期 真 　空 　科 　学 　与 　技 　术 　　　　　　　　　　 ( ) 　　　　　　　　　　　　　　 2002 年 1 月 VACUUM SCIENCE AND TECHNOLOGY CHINA 5 　 复合静电磁浸没透镜的宽束曲轴 聚焦性质及像差理论 程 　敏 　唐天同 　姚振华 (西安交通大学电子与信息工程学院电子科学与技术系 　西安 　710049) Curvilinearaxis Focusing and Aberration Theory of Wide Electron Beams for Combined Electrostaticimmersion Magnetic Lens Systems Cheng Min ,Tang Tiantong ,Yao Zhenhua Department of Electronics Science and Technology , School of Electronics and Information Engineering , Xi ’an Jiaotong University , Xi ’an , 710049 , China 　　Abstract 　Curvilinearaxis Gaussian electron optical properties and aberration characteristics of the novel electrostaticimmersion magne tic lenses are studied. Based on general wide beam and curvilinearaxis theory ,central trajectory equations and paraxial trajectory equations are obtained in local orthogonal coordinates ,and all of the secondorder aberration coefficients are derived using the software package Mathematica. As an example ,the Gaussian focusing properties and the secondorder curvilinearaxis aberrations of an electrostaticimmersion magnetic lens , the axial field distributions of which can be analytically expressed ,are calculated and the diagrams of secondorder aberrations are also given. 　　Keywords 　Electrostaticimmersion magnetic lenses ,Curvilinearaxis ,Aberration ,Trajectory 　　摘要 　研究了新型的复合静电磁浸没透镜的曲光轴高斯电子光学性质及像差特性。应用宽束曲轴理论 ,导出了三维局 部正交坐标系中的电子运动的中心轨迹方程和曲光轴的近轴轨迹方程 ;利用数学软件 Mathematica 推导出了复合静电磁浸没 透镜全部曲轴二级像差系数。作为实例 ,文中针对轴上磁场和电场具有某种解析表达式的旋转对称的静电磁浸没透镜系数 , 计算了它的曲轴高斯聚焦特性和二级像差 ,并给出了二级像差分布图形。 关键词 　静电磁浸没透镜 　曲光轴 　像差 　轨迹