共查询到19条相似文献,搜索用时 125 毫秒
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本文提出了利用函数逼近的数值迭代方法精确求解电磁复合场中电子成像系统三级几何像差方程式的概念,避免了传统电子光学近似计算造成的附加误差,提高了像差计算的精度,为高精度电子光学设计提供了可信的依据。 相似文献
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偏转像差中的Dilemma效应 总被引:2,自引:0,他引:2
本文应用多级场像差校正理论,通过对大偏转角下五级偏转像差中的彗差进行分析得出,在五级偏转彗差中存在Dilemma效应,即五级彗差的某种线性组合是一常数,它不受十极场的影响。五级彗差应在这个常数为0或较小值时,通过调整十极场分布进行校正,对影响Diemma常数的因素进行了计算分析。 相似文献
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以轴对称光学系统的初级矢量波像差理论为基础,通过引入孔径缩放因子和孔径偏移矢量,获得了离轴反射光学系统初级像差特性。通过分析可知:离轴反射光学系统的初级像差依然由球差、彗差、像散组成。由于孔径缩放因子存在,离轴反射光学系统的波像差系数均有不同比例的减小,且轴对称光学系统的高级孔径像差会在对应离轴光学系统中引入较低阶孔径像差,例如轴对称光学系统未校正球差,对应的离轴光学系统除过球差外还将引入彗差、像散等。相比于轴对称光学系统的像差,由于孔径偏移矢量的引入,离轴反射光学系统的像差不再关于中心视场旋转对称,有可能在轴外视场产生像差零点。 相似文献
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为了方便快速地计算像差,采用MATLAB中GUI工具,从球面光路计算的向量公式出发,得到了一计算像差的程序界面,在程序界面输入各个相关参量,点击界面上各种像差菜单就能得到不同视场角在光瞳上不同入射点的各种像差,并可以计算系统的焦距和理想像面的像距以及给出像面的模糊程度(同一物点发出的不同方向光线的聚焦程度的具体数值。结果表明,该软件程序语言简单,程序语句大大减少,占用机时少,运行结果正确。程序通过编译后可以脱离MATLAB运行环境独立运行。 相似文献
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随着应用光学领域的蓬勃发展,对于成像光学系统的像质需求越来越高。自由曲面的多设计自由度使其具有优异的像差补偿能力,常被用于高效像差补偿器件,而设计出具有良好像差补偿效果的自由曲面是提升系统像质的关键。这里基于矢量像差理论,介绍了一种针对成像系统像差补偿的Zernike型自由曲面设计方法。并以望远偏心系统作为实例,利用所提出方法设计了该系统的像差补偿自由曲面,并借助空间光调制器开展实验研究。仿真与实验结果均表明,所提出方法能够得到有效补偿望远偏心系统像差的自由曲面,像差补偿后光斑尺寸降低至补偿前的43.9%,其像差补偿效果优于传统标量像差理论优化法设计结果,该方法在自由曲面成像系统设计方面具有一定的应用研究价值。 相似文献
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波像差与光束质量指标的关系 总被引:10,自引:3,他引:7
用数值计算的方法,研究了不同类型波像差及其组合的均方根值(RMS)和β及Strehl比的关系,建立了拟合关系式,并以此分析了Kolmogrof湍流的r0与β的关系 相似文献
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Liwei ZHOU 《中国光电子学前沿》2008,1(1)
A new theory for temporal aberrations of dynamic optics by applying the direct integral method is put forward in the present paper. A new definition of temporal aberration is given, in which a certain initial energy of electron emission emitted from a photocathode along the axial direction √εz1(0 ≤√εz1≤√ε0max) was taken as a criterion. New expressions of the temporary aberration coefficients in integral forms for the electron optical imaging systems have been deduced. An electrostatic concentric spherical system model is used to test and verify expressions of the coefficients given by the "direct integral method" and "τ variation method". The analytical solutions prove that both methods are correct and equivalent.Compared to the "τ variation method", the direct integral method only needs to carry out the integral calculation for the three geometrical temporal aberration coefficients of the second order, which is more convenient and suitable for computation in the practical design. Finally, results of the study for the theory of temporal aberrations of electron optical imaging systems, from the point of view of methodology, have been elaborated. 相似文献
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本文利用数值仿真技术对复合场中电子成像系统的像差理论做了研究。基于一种新的计算方法编写了一套完整的像差计算程序,由此可求得任意初始条件下复合场中电子成像系统的三级几何像差。其计算精度可比传统软件的提高四倍以上,为高精度电子光路的设计提供了可靠的理论工具。 相似文献
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Microwave-optical image formation by a lens focusing system is studied in the presence of aberrations. The theoretical approach is based on diffraction and aberration theories and a modified diffraction integral is presented, showing that previously unreported effects describable as additional primary order aberrations exist due to aperture inclination. Direct relationships are shown to exist between the geometry of Airy dark rings and the type and amount of aberration present, thus providing a means for determining the aberrations present in a physical system. The practical part of the study compares numerical evaluations of the modified diffraction integral with experimental measurements. Results presented are for the case of a solid dielectric microwave lens operated at 3.2-cm wavelength. Detailed maps of phase and intensity contours are given, showing the three-dimensional structure of the image region. 相似文献
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关于Tau变分法研究电子光学成像系统的时间像差理论 总被引:2,自引:1,他引:1
本文采用新的时间像差定义,考察了"Tau变分法"研究电子光学成像系统的时间像差理论.本文表明,"Tau变分法"所给出的以微分方程形式表示的几何时间像差系数,亦可获得积分形式的表示式,证明了"直接积分法"与"Tau变分法"这两条途径殊途同归. 相似文献
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Aberration theory of arrayed waveguide grating 总被引:4,自引:0,他引:4
The general aberration theory of arrayed waveguide grating (AWG) is proposed in this paper. The derived conclusions can be applied to any symmetrical AWGs. With the aberration theory, the spectral response can be optimized. Some performances of an AWG, for example, crosstalk and channel number, are expected to be improved by reducing the aberrations. A common AWG with the Rowland geometry has low aberrations for the absence of the second-order aberration. To further reduce the aberrations, nonstandard AWGs are considered. The AWG based on three stigmatic points is proved to have a perfect performance 相似文献