计算全息图（CGH）作为零位补偿器，越来越广泛地应用于高精度非球面检测领域。CGH的设计、编码、加工和装调等误差，直接限制了非球面的检测精度。提出一种切实可行的检测非球面的流程与方法，完成了对CGH基底的标定、参考镜的绝对标定和CGH的畸变校正，实现对非球面的高精度检测。除了采用传统的平方根之和(RSS)误差合成分析方法外，还通过与无像差点法测量结果的对比，从实验上获得了此方法的测量精度。实验结果表明，利用CGH对非球面进行检测的精度可以达到3.9 nm[均方根(RMS)值]。

Computer-generated hologram (CGH) is more and more popularly applied in the high-precision testing of asphere as high-accuracy null compensator. The errors of design, coding, fabrication and alignment restrict the testing precision. A practicable method to test the asphere precisely is presented, and the calibration of CGH substrate, the calibration of reference surfaces, as well as distortion correction to improve the testing precision are accomplished. In order to obtain the measurement precision, in addition to the traditional root square sum (RSS) error analysis, the testing precision is directly evaluated through experimental comparison with the method of aberration free image conjugate point. The experimental result shows that the testing precision of asphere with CGH could reach 3.9 nm [root mean square (RMS)].