小F数毫米波双曲透镜扩展半球透镜成像特性分析

Imaging performance of hyperbolic lens/extended hemispherical lens with small F-number at millimeter wavelengths

采用射线追迹结合Stratton Chu矢量衍射积分公式的方法分析计算了小F数双曲透镜和“倒置显微镜”的焦面成像特性 .比较计算结果和实验数据发现 ,该方法是有效的 .将 2种透镜的焦面场功率分布和Airy斑分布进行对比 ,发现在双曲透镜后加上扩展半球透镜可以极大改善前者的成像性能 .同时研究了双曲透镜的像场弯曲现象 ,分析了频率对像场弯曲的影响 。

The ray tracing method and vectorial Stratton-Chu diffraction Integration are applied in the analysis of the imaging performance over the focal planes of hyperbolic lens and reverse microscope lens system with small F-number. This method is proved to be effective by the correspondence between simulated result and experimental data. It is found that adding an extended hemispherical lens to the hyperbolic lens can improve the imaging performances. The field curvature phenomenon is studied and the effect of frequency is also analyzed. An image of a reverse L type object simulated with the above method is presented.