太阳观测已全面进入高时空分辨率时代，对望远镜跟踪精度要求达到1角秒/30分钟甚至更高。然而，地平式太阳望远镜库德焦面相对于卡焦，经过了一系列的引导光路和消旋系统，从而产生了非常复杂的跟踪误差。目前，对这种跟踪误差还缺乏一种通用的解决方案，本项目针对这一技术难题和大型太阳望远镜研制对该技术的需求开展研究工作，旨在专门研究如何建立跟踪误差改正模型来实现库德焦面的高精度跟踪。研究内容及拟解决的关键问题包括：库德焦面跟踪误差的产生机制及轴系旋转中心实测方案；主副镜主光轴弯沉实测及其对后端系统的影响；格里高利前端系统F1焦点或F2焦点处跟踪误差实测与建模。特色和创新点为：本项目着力于研究具有普适性通用性方法的高精度跟踪方案；将库德焦面误差分成两个模型来研究，并通过轴系误差实测来建立引导光路误差模型。研究成果将直接应用于在运行的NVST、在研制的AIMS，以及计划中的CGST等其它太阳望远镜。

Solar observation has entered the era of high spatial and high temporal resolution, and the tracking accuracy of telescopes is required to reach 1.5 arc second/30 minutes or even higher. However, relative to the Cassegrain focus, the Coude focus of the Azi-Alt mount solar telescope passes through a series of guiding optical paths, therefore, it produces relatively large tracking error. At present, there is still a lack of a general solution to this tracking error. In view of this technical problem and the need for the development of large solar telescopes, this project carries out research work on this technology, the purpose of this research is to study how to establish a tracking error correction model to achieve high-precision tracking of coude focal plane.The research contents and key problems to be solved include: The generation mechanism of tracking errors in coude focal plane, and measuring scheme for mechanical rotating center of telescope axes; Measurement of deflection for primary and secondary mirrors system and its impact on back-end system; Measurement and modeling of tracking errors at F1 Focus or F2 focus in Gregory optical system. The characteristics and innovations are as follows: This project focuses on the research of high-precision tracking scheme with universal methods; The error model in coude focal plane is divided into two models, and the error model of guided optical path is established by measuring the errors of axes. The research results will not only be directly applied to the one meter-scale solar telescopes: NVST in operation and AIMS under development, but also to other solar telescopes, such as the planned CGST , etc.