为了提高双光纤点衍射干涉仪的检测精度，需要对干涉仪装置中两个波前参考源(WRS)的系统误差进行标定。设计了波前参考源的标定过程及标定算法，通过沿被检光学系统光轴四次旋转90°求出波前参考源的沿轴旋转非对称误差，沿倾斜轴四次旋转90°求出波前参考源的沿倾斜轴旋转非对称误差，然后利用两者之差采用最小二乘法求出波前参考源的旋转对称误差，将对称误差和非对称误差相累加求出波前参考源的系统误差。采用计算机模拟了标定算法的整个流程，当波前参考源沿光轴和倾斜轴旋转的旋转公差在±1°范围内时，采用36项泽尼克多项式进行标定的测试误差均方根值小于0.01 nm，在标定精度允许的范围内。通过模拟验证了标定算法的正确性并给出波前参考源的旋转公差范围。

In order to improve the measuring accuracy of double fibers point diffraction interferometer, system errors of two wavefront reference sources (WRS) should be calibrated. A calibrating process and calibrating algorithm of WRS are designed. The non-axisymmetric errors of WRS about optical axis are obtained through rotating the tested optical system around optical axis by four times. The non-axisymmetric errors of WRS about oblique axis are obtained through rotating the tested optical system around oblique axis by four times. Then the axisymmetric errors of WRS are gotten by the least squares, and the system errors of WRS are equal to the sum of the axisymmetric errors and non-axisymmetric errors. The process of calibrating algorithm is simulated by computer. When the rotating tolerances of WRS are in the range of ±1°, the root mean square value of measuring error is less than 0.01 nm using the 36 terms of Zernike polynomials, which is in the range of calibrating accuracy. The validity of calibrating algorithm is verified and the rotating tolerances of WRS are given by simulating the calibration.