为了实现大口径凸面反射镜检测,研究了大口径标准镜组的设计与研制技术。针对口径Φ为350mm、焦距为4400mm的标准球面镜组,完成了标准镜头设计分析、面形和曲率半径误差标定以及系统集成与实验验证。光学设计软件模拟分析结果表明镜头设计波像差达到0.0001λ[峰谷值(PV),λ=632.8nm],该标准镜头参考球面标准镜面形加工精度达到0.088λ(PV,λ=632.8nm)、0.006λ[均方根(RMS),λ=632.8nm],某项目Φ为320mm、R为4092mm的碳化硅凸面反射镜最终加工检测结果达到0.102λ(PV,λ=632.8nm)、0.011λ(RMS,λ=632.8nm)。结果表明采用该大口径标准球面波透镜组为大口径长曲率半径凸面反射镜提供了一种高精度检测的手段,解决了大口径长曲率半径凸面反射镜检测难题,采用该标准球面镜结合基于数字样板的非零位检测方法也可完成浅度非球面或自由曲面面形实时高精度检测。
In order to realize testing of a large aperture convex sphere, large aperture standard transmission spheres are designed and manufactured. The system focal length of 4400 mm, Ф 350 mm aperture are required. The design and performance comparison, surface quality and radius of curvature testing, large aperture SiC convex sphere surface testing are complished. The simulation result analysis of optical design software shows that the wavefront performance of the system design is 0. 0001λ [peak to valley (PV), λ = 632.8 nm], and it can offer a high-quality spherical wave and the reference spherical surface quality is up to 0. 088λ (PV, λ= 632.8 nm), 0. 006λ[root mean square (RMS), λ=632.8 nm]. For a SiC convex sphere of Ф320 mm aperture and 4092 mm radius of curvature the manufactured results of the surface quality are up to 0. 1022, (PV, λ = 632.8 nm), 0. 011λ (RMS, λ= 632.8 nm). The results indicates that the large aperture standard transmission spheres are helpful for the testing large aperture convex sphere surface with large radius of curvature, the highly precision testing is complished only by standard sphere and non-null testing method based on digital mask, and the problems of large-aperture convex asphere or freeform mirror testing are solved.