Novel 3D measurement system based on speckle and fringe pattern projection

An efficient three-dimensional shape measurement system is proposed, which is based on the combining projection of single digital speckle pattern and phase-shifting fringe patterns. At the beginning, the initial corresponding point for each pixel is obtained by a novel speckle-phase combination method. The initial information can be calculated by the single speckle pattern in a short time, while the phase information is used to ensure the results. Unlike the conventional methods, it is not necessary to obtain the unwrapped phase, therefore the number of projected patterns is reduced greatly. Then accurate corresponding coordinates are obtained according to the wrapped phase. Three cases are analyzed while adjusting the initial corresponding coordinates locally. Thus accuracy coordinates are obtained without missing or incorrect points. Experiments demonstrate that we can achieve accurate reconstruction results with reduced measurement time by the proposed method.