基于矢量衍射理论的相位型光瞳滤波器设计

根据矢量衍射理论,提出了一种设计纯相位型光瞳滤波器的新方法根据该方法所设计的滤波器主要应用于采用高数值孔径显微物镜的成像系统对点扩散函数中的指数因子进行二次近似处理后,可以得到超分辨参量与滤波器参量的近似关系式以三区相位型滤波器为例,讨论了该近似关系式的有效性给出一个设计实例,根据所要求的超分辨性能要求设计滤波器.模拟结果表明,该滤波器达到了设计要求,最后利用共焦系统点扩散函数的乘积特性,大大减弱了旁瓣的影响.

Design of Phase-only Pupil Filters Based on Vector Diffraction Theory

According to the vector diffraction theory, a new design technique of phase only filters is proposed. The filters designed with this method can be applied to imaging systems equipped with high aperture objectives. The exponential factor is expanded as a power series and kept only the first three terms to calculate the intensity point spread function. The approximate relationship between superreso lution parameters and filter parameters can be obtained. The validity of this approximate relationship is discussed for three zone pupil filters. A design pa radigm in which super resolving filters are designed in terms of this relationship is given. Numerical results show that those pupil filters can achieve axial superresolution. In the end, those filters are applied to confocal microscopy to reduce the strength of secondary lobes.