Design and Realization of Wide Field-of-View 3D MEMS LiDAR

Light detection and ranging (LiDAR) sensors are promising for automated transportation to detect the surrounding environment. However, most LiDAR solutions are complex and bulky. By designing a MEMS-mirror-based LiDAR, we can improve the volume constraints, but MEMS mirrors could limit scanning angles. In this work, we simulated and demonstrated a MEMS LiDAR system to solve the current obstacles. Combining a MEMS mirror and a wide-angle lens into the system, small-volume and large field-of-view (FOV) LiDAR systems can be realized. We use ray tracing optical simulation software to design a pair of aspherical lenses to expand the scanning angle. After the laser beam passes through the wide-angle lens, the FOV can be increased to 104 degrees. The distortion of the wide-angle lens is controlled below 3%, making the scanned image precise to the actual situation. In order to experimentally demonstrate the small-volume MEMS scanning LiDAR, a modular laser rangefinder is used with a MEMS mirror. The entire system of the LiDAR scanner is around 15 cm
$\times5$
cm
$\times2.5$
cm. In the natural light environment for wide-angle LiDAR measurement, the maximum error is less than 2%. Finally, an image processing program is written to convert the scanned data into a 3D point cloud image, and the generated image proves the complete function of the proposed LiDAR.