Wang Daodang, Yang Yongying, Chen Chen, Zhuo Yongmo
State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou, China.
Appl Opt. 2011 Jun 1;50(16):2342-8. doi: 10.1364/AO.50.002342.
A point diffraction interferometer (PDI) with adjustable fringe contrast is presented for the high-precision testing of spherical surfaces. The polarizing components are employed in the PDI to transform the polarization states of the test and reference beams, and a good fringe contrast can be realized by adjusting the relative intensities of interfering waves. The proposed system is compact and simple in structure, and it provides a feasible way for high-precision testing of spherical surfaces with low reflectivity. The theory of the interferometer is introduced in detail, along with the properties of optical components employed in the system, numerical analysis of systematic error, and the corresponding calibration procedure. Compared with the testing results of the ZYGO interferometer, a high accuracy with RMS value about 0.0025λ is achieved with the proposed interferometer. Finally, the error consideration in the experiment is discussed.
提出了一种条纹对比度可调的点衍射干涉仪（PDI），用于球面的高精度检测。该PDI采用偏振元件来变换测试光束和参考光束的偏振态，通过调节干涉波的相对强度可实现良好的条纹对比度。所提出的系统结构紧凑、简单，为低反射率球面的高精度检测提供了一种可行的方法。详细介绍了干涉仪的原理，以及系统中所采用光学元件的特性、系统误差的数值分析和相应的校准程序。与ZYGO干涉仪的测试结果相比，所提出的干涉仪实现了约0.0025λ的均方根值的高精度。最后，讨论了实验中的误差考虑因素。
