非零位补偿检验非球面技术

为了无需定制补偿透镜或者计算全息等就能实现对非球面光学元件的检测,提出了非零位补偿测试非球面的方法。对非零位补偿检验非球面中的部分补偿法、数字样板法和子孔径拼接法的基本原理和基础理论分别进行了分析和研究,建立了合理的数学模型,并对其具体的实现步骤和测试流程进行了分析和规划。结合工程实例,分别利用数字样板法和子孔径拼接法对一口径为350 mm的浅度非球面进行了面形检测,两种方法面形的PV值和RMS值的偏差分别为0.015和0.002(=632.8 nm),并设计和组建了部分补偿检验装置对一高精度凸双曲非球面反射镜进行了测量,其面形的PV值和RMS值分别为0.183和0.018。

Testing of aspheric mirror by non-null compensation method

For the purpose to overcome the difficulty of testing aspheric surfaces by null lens or CGH (Computer-Generated Hologram), the non-null testing was proposed. The basic principle and theory of testing asphere by digital plane, partial compensation and subaperture stitching interferometry(SSI) were analysed and researched, and each testing model and flow chart were established. Combining examples, an asphere of little departure with the aperture of 350 mm was tested by the digital plane and SSI, respectively. As results, the difference of PV and RMS error between SSI and partial compensation is 0.015 and 0.002( is 632.8 nm), respectively. The prototype and setup for testing asphere by partial compensation were devised and developed, a precise convex asphere is measured by this method, the PV and RMS of the surface error is 0.183 and 0.018, respectively.