为解决大口径非球面碳化硅反射镜加工过程中材料去除效率与加工精度之间的矛盾，提出使用组合加工技术进行加工。介绍了组合加工技术的基本原理与数学模型。通过与经典计算机控制表面成形技术(CCOS)加工技术进行对比，说明了组合加工技术的优势。结合工程实例，对一块2040mm口径非球面碳化硅反射镜进行研磨。以其中一次加工周期为例介绍了组合加工技术在大口径非球面碳化硅反射镜加工过程中的应用。经过一次完整的组合加工过程，工件表面面形误差峰谷(PV)值由8.72 μm收敛至4.91 μm，均方根(RMS)值由0.91 μm收敛至0.52 μm,证明了组合加工技术的有效性。

Use multi-mode optimization technique to improve material remove efficiency and precision. Introduced principal theory and mathematical model of multi-mode optimization technique. Compared with traditional computer controlled optical surfacing (CCOS) technique, we introduce the advantage of multi-mode technique. In the last, we grind a SiC mirror using multi-mode technique. Take SiC mirror with caliber of 2040 mm as an example to introduce how the multi-mode technique applied in grind large aspheric SiC mirror. After a complete multi-mode process, peak valley (PV) of the surface converges from 8.72 μm to 4.91 μm and root mean square (RMS) of the surface converges from 0.91 μm to 0.52 μm， which demonstrates the validity of the multi-mode technique.