高精度球面检测中调整误差的精确校正

针对高精度球面检测中球面的调整误差影响,分别研究了波前离焦和倾斜所引入的Zernike像差项,并以此为基础,提出了基于Zernike系数的高精度球面调整误差校正方法.利用Zygo干涉仪对大数值孔径的待测球面进行了检测,实验中对待测球面同时引入波前离焦和倾斜误差,再分别运用所提出的校正方法和传统的消倾斜离焦校正方法得到波面数据并进行对比,进而验证了所提出的校正方法的可行性.实验结果表明,利用该方法可有效地校正大数值孔径球面存在调整误差时所引入的球面像差,并且实验中的校正精度达到了0.002λ（λ为检测光波长）.提出的基于Zernike系数的球面调整误差校正方法可降低对于调节机构的精度以及检测人员的经验要求,在高精度球面检测中具有非常高的实际应用价值.

Accurate Calibration of Misalignment in High-Precision Spherical Surface Testing

Based on the detailed analysis of the Zernike aberrations of wavefront errors, including the wavefront defocus and tilt, introduced by test surface misalignment in the high-precision spherical surface testing, a method for the misalignment calibration using Zernike coefficients was put forward in this paper. The experimental validation of the proposed calibration method was carried out with Zygo interferometer, in which a high-numerical-aperture spherical surface was tested by introducing both the wavefront defocus and tilt. The measured data were then respectively processed with the proposed method and the traditional calibration method for removing the tilt and defocus errors, by which the feasibility of the proposed method was demonstrated. This method is effective for calibrating the spherical aberration introduced by misalignment of high-numerical-aperture spherical surfaces, and an accuracy of 0.002A （A is the optical wavelength in the test） was achieved in the experiment. The proposed method can help lower the requirement of the adjusting precision of mechanical devices as well as the skill of testing personnel, which can be applied to the high-precision measurement of spherical surface.