成像系统均方根半径及调制传递函数的计算  

Computation on Root Mean Square Radius and Modulation Transfer Function in Imaging Systems

作　　者：张良忠[1] 金伟其[2] 周立伟[2] 

机构地区：[1]北方交通大学光波技术研究所,北京100044 [2]北京理工大学光电工程系,北京100081

出　　处：《电子学报》2000年第8期5-8,共4页Acta Electronica Sinica

基　　金：国家自然科学基金

摘　　要：本文给出了逸出电子在最佳像面上落点的均方根半径值及直观图形表示 ;以实际管型为例 ,βeta分布取β1,8至 β2 ,1,检验了均方根半径的变化状况 ,证明了理论分析的正确性 ;从数据上检验了均方根半径不仅可以表征系统鉴别率特性的好坏 ,而且和调制传递函数的优劣在像面上是一一对应的 ;证明了用指数形式表示系统的调制传递函数具有计算速度快、形式简洁、使用方便 。In the paper,the value of RMS radius and the visual picture of escape electron dropped spots in optimum image plane has been given.The present paper has offered data to prove that when the βeta distribution changes from β 1,8 to β 21 ,the RMS radius value increases gradually,corresponding with theoretic analysis.It has offered data to check that the RMS radius not only can characterize the system resolution properties,but also does it correspond with the electron optical modulation transfer function (MTF) in image plane,and proved that expressing the system MTF by exponential function will have the properties of fast computation speed,succinct expression,convenient usage,and have enough accuracy in low frequency space.

关 键 词：均方根半径 调制传递函数 成像系统 数值计算 

分 类 号：TN202[电子电信—物理电子学]