On-line calibrated and directional point structured light 3D imaging with selectivity based on piezoelectric actuators and microlens array

Three-dimensional imaging based on structured light is an effective method to achieve short/medium distance and high-precision measurements. Microlens array scanner, as a semi-solid-state 2D optical phased array, can flexibly control the two-dimensional tilted wavefront of the exit beam. In this study, we propose a 3D imaging technique based on the microlens array scanner to project the directional point structured light to the target of interest instead of the traditional full field of view (FOV) projection method and explore an online calibration method to achieve 3D reconstruction, offering a complete technical roadmap for selective 3D imaging. If required, full FOV 3D imaging can also be achieved by full FOV projection or stitching. We experimentally demonstrate 3D reconstruction of three different targets. An accuracy measurement method based on an optimization algorithm is proposed. The accuracy of our system is smaller than 0.2 mm at a detection distance of 2 m, indicating the feasibility of the submillimeter measurement platform. To the best of our knowledge, the online calibration and selective 3D imaging of structured light that we have demonstrated is the first time it has been realized. Our method can pave the way for practical applications such as surface contour detection, robotic vision, and autonomous driving.