新面型短程透镜的制备研究

STUDY OF AN OPTIMUM GEODESIC LENS FABRICATION

根据解析理论新的精确公式进行设计并用单点金刚石超精切削加工制备，研制出一种优化的非球凹面短程透镜．透镜含光滑无奇点圆边，与平面连接的边缘曲率半径为无限大．样品制备在４５×２０×２．５ｍｍ３的ＬｉＮｂＯ３衬底上，每片有两个孔径８ｍｍ、焦距８ｍｍ的无球差非球面短程透镜，利用６７０ｎｍ波长的半导体激光器端面耦合入样品一端，在另一端测得焦点光斑半宽度为２．９μｍ．

geodesic lens with the optimum profile meridional shape calculated from the new exact theoritical formula[2. 3] was fabricated by the single diamond machine. The curvature radius at the point connected with the planar surface is infinite, and doesn't have singulity. The samples of spherical aberration-free unspherical geodesic lenses were fabricated on the LiNbOa substrates with the size of 45×20× 2. 5 mm, and two lenses were arranged on each substrate. The light output from a semiconductor laser with the wavelength of 670 urn was end-coupled into sample, the focal spot half-width measured at the other edge is 2. 9 μm.