为快速获取空间不连续三维物体表面的绝对相位, 提出了一种基于编码光栅的相位展开方法。该方法只需投射一幅带有编码信息的光栅条纹图像, 即可获取相位展开所必需的条纹级数信息, 从而得到整个被测表面的绝对相位信息。根据相位-深度关系, 可获得整个被测表面的三维信息。与基于格雷码的相位展开方法相比, 该方法不依赖被测物体的灰度信息, 抗噪声性能更好。该方法只需额外投射一幅编码条纹图像, 更适用于对实时性要求比较高的三维测量。通过实验证明了该方法的有效性和可行性。

In order to obtain absolute phase of spatial discontinuous object surface quickly, a phase unwrapping method based on encoding grating is proposed. In this method, a grating fringe image with encoding information is projected, the fringe order information which is needed for phase unwrapping is obtained, and then the absolute phase information of the whole measured surface is obtained. The three-dimensional information of the whole measured surface is obtained according to the phase-depth relationship. Compared with the phase unwrapping method based on the Gray code, the proposed method does not depend on gray information of the measured object and has better noise resistance. Only one additional encoding fringe is needed for the proposed method, so it is more suitable for three-dimensional measurement with high real-time requirement. The effectiveness and feasibility of the proposed method is demonstrated by experiments.