Coude 光路是大口径望远镜光学系统必要的组成部分，它将主望远镜的光束进行传递，以使其进入望远镜机下Coude 实验室，与子光学系统相耦合。在Coude 光路中，存在多块折转反射镜，反射镜之间的相对位置关系影响着系统的成像质量。因此如何保证光学元件之间的位置关系，成为光机结构研究的关键问题。根据系统要求分析并设计了各类型调整机构，包括二维半运动支撑倾斜调整机构、一维燕尾形导轨平移机构和一维精密旋转机构，机构行程大、操作便捷，既保证光学元件之间的准确位置关系，也便于装调和检测。整个研究方法适用于光机系统调整，在实践中得到了应用。

In large aperture telescope optical system, Coude path is very important though it deliver the major optical path to enter in the Coude laboratory below telescope, coupling with the sub-optical system. Coude path is composed of many deflected mirrors, and position relationship among optical elements is important for its image quality. So it’s a key technique to ensure their accurate position relationships. On the basis of system requirement, a kind of tuning mechanisms is designed, including tip/tilt tuning mechanism utilizing semi-kinetic support, Dovetail-groove rail displacement mechanism and fine revolution structure. Each of them is characterized with long stroke and convenient operation. So they not only can assure the accurate position relationship, but also are suitable for adjustment and detect. The whole research technique can be a fine reference to the optic-mechanical system, and has been utilized in actual engineering.