A three-dimensional (3D) shape measurement method based on speckle-embedded fringe patterns (composite fringe patterns) and wrapped phase-to-height lookup table (LUT) is proposed. As an auxiliary signal, speckle is embedded into the phase domain of the projected fringes, and the wrapped phase and deformed speckle modulated by the objects are demodulated by phase-shifting algorithm. With the assistance of the LUT established in advance, the candidate heights are directly obtained by the wrapped phase. Subsequently, the speckle correlation is used to eliminate the height ambiguity, and then the absolute spatial height of the measured objects can be reconstructed without projecting any additional pattern. In this paper, the cooperation of embedded speckle and LUT allows the speckle to do correlation operation in some certain smaller area of the candidate heights’ location, instead of matching within the whole measurement range, thus it can improve the computational efficiency in the determination of the unique accurate height. Theoretical analysis and experimental results have demonstrated that the proposed method can achieve high-accuracy and robust 3D shape measurement of dynamic and static complex scenes.

提出了一种基于散斑嵌入条纹图案（复合条纹图案）和包裹相高查找表（LUT）的三维（3D）形状测量方法。作为辅助信号，将斑点嵌入到投影条纹的相位域中，并通过相移算法对由对象调制的包裹相位和变形斑点进行解调。在预先建立的LUT的帮助下，候选高度可以通过包裹阶段直接获得。随后，使用散斑相关性消除高度模糊性，然后可以重建被测对象的绝对空间高度，而无需投影任何其他图案。在本文中，嵌入式散斑和LUT的配合使散斑可以在候选高度的某些较小区域内进行相关运算，而不是在整个测量范围内进行匹配，从而可以提高确定唯一准确高度时的计算效率。理论分析和实验结果表明，该方法可以实现动态，静态复杂场景的高精度，鲁棒的3D形状测量。