绝对检测技术是剔除干涉仪系统误差进而提高面形检测精度的有效手段。基于单次旋转的绝对检测技术由被测球面绕光轴旋转前后的检测数据，采用基于最小二乘法的Zernike多项式拟合，剔除系统误差，获得被测面的旋转非对称面形误差。详细推导了理论计算公式，分析了单次旋转角度对算法检测精度的影响，并和多次旋转法作了对比，其残差均方根(RMS)值约为1.5 nm。该方法只需一次旋转两次检测，在保证检测精度的同时简化了检测过程。

The absolute testing method is an effective way to remove system errors of interferometer and improve the accuracy of the measurements of surface deviation. The method of single rotation based on least-squares fitting of Zernike polynomials requires rotating the spherical surface once and taking two measurements to calculate the rotationally asymmetric surface deviation. The formulas are derived theoretically in detail and the analysis of the impact of angle of single rotation on algorithm accuracy is presented. To prove the effectiveness of the method, the experimental result obtained from this method is compared with that of the multi-rotation method, and they meet well.