利用多频外差原理推导四频光栅条纹相位解包裹过程, 同时, 为了减小相位解包裹误差, 提出一种相位校正的方法, 并分析了相位校正对匹配结果的影响;通过将校正后的绝对相位值作为匹配的依据, 利用极线对上基于相位的亚像素匹配方法;利用三维重建技术获取物体的三维点云数据。实验结果表明: 平面测量的匹配率提高了4.97%, 测量精度达到0.189 5 mm。

A phase unwrapping method based on multi-frequency heterodyne principle by projecting four different frequency fringes was deduced. Meanwhile, In order to reduce the phase unwrapping errors, a phase correction method was proposed, and the effect on matching result was compared before and after phase correction. In order to improve the accuracy of the matching, the revised absolute phase value was used as the basis for matching. Besides, the sub-pixel matching algorithm was utilized based on phase linear interpolation.Finally, the 3D reconstruction technology was used to obtain the three-dimensional point cloud. Results show that the matching rate of plane measurement is increased by 4.97%, with the measurement accuracy of 0.189 5 mm.