互补格雷码双 N 步相移的彩色编码光栅投影轮廓术

在三维轮廓测量领域，互补格雷码相移法能够得到连续的展开相位，然而，单组相移条纹导致其测量精度极易受到周围环境变化的影响，且传统投影方式增加了干扰的引入。针对此问题，本文提出了一种基于彩色编码光栅投影的互补格雷码双N步相移法。首先将双N步相移条纹和互补格雷码条纹混合编码成彩色条纹，然后依次投射到目标表面，最后从采集的彩色条纹中提取相位信息分别进行相位解算、融合后求得表面三维形貌。为了验证本文所提方法，将该方法与传统互补格雷码N步相移法以及三频外差法进行了对比实验。实验结果证明，本文方法能够获得高精度表面形貌信息，有效降低测量误差，同时检测效率提高50%。

Color coded grating projection complementary gray code double N-step phase shift profilometry

In the field of three-dimensional contour measurement, the complementary gray code phase shift method can obtain continuous unwrapped phase. However, the measurement accuracy of a single set of phase shift fringes is easily affected by the changes in the surrounding environment, and the traditional projection method increases the introduction of interference. To solve this problem, this article proposes a complementary gray code double-N-step phase shift profilometry based on the color-coded grating projection. First, the double-N-step phase shift fringe and the complementary gray code fringe are mixed and coded into color fringe, and then projected onto the target surface in turn. Finally, the phase information is extracted from the collected color fringe, and the phase is calculated and fused to obtain the three-dimensional surface topography. To evaluate the proposed method, a comparative experiment is carried out among this method, the traditional complementary Gray code N-step phase shift method and the three-frequency heterodyne method. Experimental results show that this method can obtain high-precision surface topography information, effectively reduce the measurement error, and improve the detection efficiency by 50% .