为了满足大型光学镜面加工对在位检测的需求,探索了一种应用相位恢复技术的新型镜面测量方法.构建了基于离焦光场的相位恢复测量系统并实现了与此系统相适应的相位恢复算法,此测量系统结构简单且不易受环境振动影响.在此系统基础上,详细分析了各种误差因素以及系统测量;隹确度和测量范围,并针对在位检测的特点和要求,研究了此方法在应用中的可靠性.对一面口径430mm的球面反射镜进行了分平台在位测量实验.实验中分析了不同测量参量对测量结果的影响.相位恢复测量与干涉测量结果对比较为吻合.理论分析和实验都表明该方法切实可行,检测准确度满足光学镜面研抛加工要求。
To meet the requirement of on site testing in the manufacture of large mirror surfaces, a new method using phase retrieval technology was developed. A phase retrieval testing system based on the wave field at defocus was established together with the phase retrieval algorithm that serves the system. The testing system is simple and free from vibration,based on which,the error sources with testing precision and scope were analyzed in detail. The reliability for practical testing was also studied according to the requirement of on sit testing. The testing for a ball mirror of 430 mm aperture was carried out, where the affection from different testing configuration was also studied. The testing result showed high consistency compared with the result from interferometer. It shows that this method is feasible for high accuracy and suit for the requirement of polishing process.