为了提升反向条纹测量系统的精度，提出了利用三频时间相位补偿算法来改善投影机-相机测量系统非线性误差的测量方法。在测试物体上投影两套具有特定相位偏移的结构光条纹，基于三频时间相位展开方法获得展开相位。具有特定相位偏移的两套条纹测量得到的系统非线性相位误差具有大小相等、符号相反的特性，因此可以通过简单的算术计算来消除或减弱系统的非线性影响，从而提升测量精度。设计了模拟仿真和实物对比实验对所提方法进行验证，实验得到的相位标准差分别为6.6122×10-4 rad和0.0087 rad。实验结果表明，所提方法使反向条纹测量的精度有了大幅改进，验证了该方法的有效性。

In order to improve the measurement accuracy of inverse fringe, the measurement method based on the three frequencies temporal phase compensation algorithm is proposed to alleviate the nonlinear error of projector-camera measurement system. Two sets of structured light fringes with specific phase offset are projected onto the testing object, and three frequencies temporal phase unwrapping method is used to obtain the unwrapped phase. The system nonlinear phase errors measured by the two sets of fringes with specific phase offset have the characteristics of the same absolute value and opposite sign. So the effect of the system nonlinear error can be eliminated or alleviated by the simple arithmetic calculation, and the measurement accuracy can be improved. The analog simulation and real object contrast experiments are designed to verify the proposed method. Phase standard deviations in the experiments are 6.6122×10-4 rad and 0.0087 rad, respectively. The experiments results show that the proposed method has a great improvement in inverse fringe measurement accuracy, and the validity of proposed method is verified.