提出了一种采用组合滤波窗提高复合光栅实时三维测量精度的新方法，通过对复合光栅相位测量轮廓术(PMP)原理的分析，发现当从采集的变形复合光栅中解调相移变形条纹时，解调精度与滤波窗的选择有关。通过对几种常见滤波窗函数的分析和比较，设计了一种将汉宁窗和矩形窗相结合的新型滤波窗。由于组合窗的滤波精度与物体频谱分布情况（面型情况）有关，在复合光栅三维实时测量中，对频谱成分适中的Peaks函数物体进行数字模拟，得到测量该类物体所需的组合窗口优化参数分布图，用得到的理论数据指导处理频谱成分适中的实物实验，有效提高了复合光栅实时三维测量精度。数字模拟和实验均证实了该方法的有效性和适用性。

A new method for improving accuracy of real-time three-dimensional (3D) measurement based on a composite grating is proposed. By analyzing the composite phase measuring profilometry (PMP), it is found that phase demodulation precision is related to filtering window choice when demodulating the deformed phase shift stripes from a deformed composite grating. By analyzing and comparing several common filtering windows, a new kind of filtering window which is combined Hanning and rectangular window together is designed. Because filtering precision is related to distribution of spectrum, by digital simulating Peaks-function object in 3D measurement based on a composite grating, distribution of optimized parameters of combined window is obtained. Using these data, the proper object in experiment to improve the accuracy of real-time 3D measurement based on a composite grating can be realized. Both simulating and actual experimental results prove the method′s effectiveness and practicability.