相位恢复镜面检测性能研究

在镜面面形检测中应用相位恢复技术,可以简化测量系统,增强抗震动干扰能力.为确定相位恢复镜面测量系统的性能,从两个方面进行了研究.结合提出的相位恢复测量系统,运用傅立叶光学和几何光学理论讨论硬件对测量范围的限制,确定了CCD像素尺寸与被测镜f数,CCD整体尺寸与被测镜最大像差之间的定量关系.从算法效能角度,采用单因素仿真实验考察算法对镜面误差幅度和频率的适应性.仿真结果表明,表面误差频率在31.4mm附近时算法效率较高,过高或过低都将降低算法的效率;误差幅值的影响不大,镜面误差RMS值大至六个波长,小至百分之波长算法都可以胜任.

The Capability of Phase Retrieval Metrology for Mirrors

Applying phase retrieval to mirror metrology can simplify the measurement system and increase the ability of resisting the vibration effects. The capability of phase retrieval testing system for mirrors is described from two aspects: its hardware and algorithm. According to the theory of Fourier optics and geometry optics, the pixel size and the total size of CCD spherically limit the f-number and the departure of a wavefront respectively. The adjustability of phase retrieval algorithm to different figure errors is observed afterward. A series of simulation experiments show that the algorithm is high-powered when the period of figure errors is about 31.4mm, and the performance is weaker when over or under that frequency; but the algorithm is reliable when the RMS value is up to six wavelength or as small as one percent wavelength.