极大望远镜直接共相定标和维持关键技术研究

项目名称： 极大望远镜直接共相定标和维持关键技术研究

项目编号： No.U1231110

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： 李烨平

作者单位： 中国科学院国家天文台南京天文光学技术研究所

项目金额： 70万元

中文摘要： 国际上未来30米级以上极大口径地面光学/红外望远镜，主镜均由大量子镜拼接而成。针对极大望远镜拼接这一关键技术需求，提出一种拼接镜面子镜高低差直接测量定标维持方法的研究。通过设计一种基于镜面膜层电容传感器的方法，可以直接测量定标相邻子镜的高低差以及子镜二面角误差，再辅以一种基于望远镜系统的自定标的自准直的子镜二面角光学波前传感方法，能避免对天观测时大气视宁度影响以及对天文观测目标的检测需要，完全能够实现全部子镜的相邻高低差和法线倾斜误差的实时检测定标，并与位移促动器形成实时大闭环，实现极大望远镜拼接共相的自定标和实时维持。研究掌握这项关键技术，可应用于未来我国极大望远镜的研制，也可基于此核心技术参与国际上极大口径光学/红外望远镜的合作研制。研究突破这项关键技术，将解决望远镜共相拼接的国际性难题、促进我国拼接镜面主动光学技术的极大发展，并使之走在国际前沿，并对我国的天文学和国家安全有重要意义。

中文关键词： 电容位移传感器；直接共相；拼接镜面；主动光学；极大望远镜

英文摘要： Primary mirrors for the international future ground-based optical/ infrared Extremely Large Telescopes (ELT) with apertures larger than 30m must be segmented and well phased by a large quantity of sub-mirrors. To meet such difficult key technology requirements, a new method is proposed to measure both the neighboring differential piston and tip/tilt error between the neighboring two sub-mirrors with a new capacity sensor form, which uses reflecting metal coating on the each mirror as an electrode, together with a auxiliary self-calibration and auto-collimation optical Shack-Hartmann sensing method through the whole telescope system. This method can completely avoid the influence of atmospheric seeing and phasing calibration source requirement of astronomical observation object, and can real-time detect the adjacent differential piston directly and normal tip/tilt errors of all sub-mirrors, and realize close-loop phasing control based on precise displacement sensors, and finally implement the phasing self-calibration and real-time phasing maintenance of the segmented mirror telescope. This research can help us grasp this main key technology of ELT. The technology can be applied into the Chinese future ELT development, and also help us participate in the international cooperated construction of ELT. It will solve

英文关键词： displacement capacity sensor；direct phasing；segmented mirror；active optics；extremely large telescope