Wang Daodang, Yang Yongying, Chen Chen, Zhuo Yongmo
State Key Laboratory of Modern Optical Instrumentation, Zhejiang University, Hangzhou, China.
Appl Opt. 2011 May 10;50(14):2024-31. doi: 10.1364/AO.50.002024.
The calibration of misalignment aberrations is a key issue in the testing of high-numerical-aperture spherical surfaces, and it is hard to separate the high-order aberrations introduced by misalignment from the measured data. The traditional calibration method is still applicable in the case of only wavefront tilt, but no longer effective in the existence of defocus. A calibration technique based on the wavefront difference is proposed to calibrate the misalignment aberrations in the presence of wavefront defocus, and it can be carried out without foreknowledge of the spherical surface under test. With the wavefront difference method, the calibration needs two separate measurements to separate the high-order aberrations. Both the computer simulation and experiments with the ZYGO interferometer have been carried out to validate the proposed calibration technique, with the accuracies better than 0.0005λ RMS and 0.0010λ RMS achieved, respectively. The proposed calibration method provides a feasible way to lower the requirement on the adjustment in the measurement, while retaining good accuracy.
对准偏差像差的校准是高数值孔径球面检测中的一个关键问题，并且很难从测量数据中分离出由对准偏差引入的高阶像差。传统的校准方法在仅存在波前倾斜的情况下仍然适用，但在存在离焦时不再有效。提出了一种基于波前差的校准技术，用于在存在波前离焦的情况下校准对准偏差像差，并且可以在无需预先了解被测球面的情况下进行。使用波前差方法，校准需要两次单独的测量来分离高阶像差。已经进行了计算机模拟和使用ZYGO干涉仪的实验，以验证所提出的校准技术，分别实现了优于0.0005λ RMS和0.0010λ RMS的精度。所提出的校准方法提供了一种可行的方法，在保持良好精度的同时，降低测量中的调整要求。
