长焦距Si微透镜阵列的制作及点扩散函数测量

Fabrication of Silicon Microlenses Array with Long Focus and Point Spread Function Measurement

针对用常规光刻热熔法制作折射型微透镜阵列的过程中 ,临界角效应严重制约了长焦距微透镜阵列制作问题 ,提出了曲率补偿法 :在经过常规光刻热熔成形和离子束刻蚀技术制成的硅微透镜阵列上再涂敷几层光刻胶 ,以降低各单元微透镜的曲率 ,然后再次进行加热固化和离子束刻蚀 .扫描电子显微镜 (SEM )显示微透镜阵列为表面极为平缓的方底拱面阵列 ,表面探针测试结果显示用补偿刻蚀法制作的微透镜的物方F数和像方F′数分别可达到 49.2 6和 5 3 .5 2 。

Refractive square based arch Si microlenses array (MLA) with long focus is fabricated by a new method named curvature compensation method. In order to decrease curvature of MLA made by the conventional heat forming photoresist method, several new layers of photoresist on it. Scanning electron microscope (SEM) show that microlens are gently arc square based, and the surface stylus measurement show that by use of the new method, object F number and image F′ number of MLA are promoted to 49.26 and 53.52 respectively, point spread functions of MLAs are more ideal and their image quality is improved.