短相干光显微干涉理论及摆臂式轮廓仪的非接触测量方法研究

项目名称： 短相干光显微干涉理论及摆臂式轮廓仪的非接触测量方法研究

项目编号： No.U1231111

项目类型： 联合基金项目

立项/批准年度： 2013

项目学科： 天文学、地球科学

项目作者： 陈磊

作者单位： 南京理工大学

项目金额： 54万元

中文摘要： 在天文望远镜制造中，非球面尤其是凸非球面的面形检测成为限制其应用发展的技术瓶颈。摆臂轮廓仪是解决这一问题的有效手段，但其接触式测头可能造成非球面表面损伤，且测头直径会引入测量误差。本项目在保留传统摆臂轮廓仪测量通用性强的基础上，基于光干涉原理，研究非接触测量技术，用光点替代固体探头消除探头直径的影响，以短相干光精确定位提高探头的位移检测精度，实现非球面从粗磨、精磨到抛光各个加工阶段的面形测量。本项目建立短相干光显微干涉模型，研究短相干光时域、空域、频域干涉条纹处理方法，实现非球面轮廓的非接触定位；揭示非球面局部陡度变化、干涉条纹载频、条纹零位偏移之间的定量关系，建立基于短相干位移传感器的非球面轮廓恢复算法；分析振动对非接触摆臂轮廓仪的影响，建立振动误差与轮廓之间误差传递的定量关系，研究振动补偿及振动抑制算法，克服测量过程中环境振动的影响。构建非接触摆臂轮廓仪装置。

中文关键词： 摆臂轮廓仪；非接触测量；短相干光；显微干涉；非球面测量

英文摘要： In astronomical telescope manufacturing, it is always difficult to measure asphere, especially convex asphere profile, which has greatly limited their application and develoment. Swing arm profilometry is thought as an effective method to solve the problem. However, contact probe in traditional swing arm profilometer may possibly damage aspheric surface and introduce measurement error because of its tip size. Without losing any measuring abilities in traditional swing arm profilometry, non-contact probe based on low-coherence interferometry is proposed in this project. Contact probe is substituted with light point and measuring accurcy is hence increased because of the high positioning ability of optical interferometry. Aspheric surface form in each fabrication period including figuring, fine grinding and polishing can be measured. The interferometric model with low coherence microscopy will be established and different interferograms will be analyzed in temporal, spatial and spectral, in order to obtain profile of the asphere under test. Theoretical relationship among local slope of asphere, fringe carrier and zero optical path difference will be derived to build asphere profile retrieving algorithm for swing arm non-contact profilometer. The influence of vibration on non-contact profiling will be analyzed to r

英文关键词： swing arm profilometry；non-contact measurement；low coherence light；interference microscopy；asphere measurement