Wide angle LiDAR demonstrator based on a resonantly operated 1D MEMS mirror capable of scanning 180°

The wish for higher-level advanced driver assistance systems requires infrared based ranging systems like LiDAR provided that it offers high speed, wide field-of-view, small size and especially low cost. The only way to combine these attributes is the use of cost-efficient and mass-producible MEMS scanners suitable for automotive applications. In this work we present a wide-angle LiDAR demonstrator for short range applications based on a single resonantly operated MEMS, a single laser and single light detector. The MEMS mirror is capable of tilting ± 45° mechanically and thus enabling a large field-of-view of up to 180°. The incorporated mirror plate has an elliptical shape of 2 mm x 4 mm in size and the overall volume of the MEMS device is less than 0.7 cm³. Low-power microcontroller based closed-loop electronics is used to keep the very high Q device within its resonance frequency range at all times enabling high scan rates of more than 3000 scans per second and accurate position detection better than 0.1°. Both automotive suitability and high energy efficiency is achieved by hermetic wafer-level sealing under vacuum as well as internal piezoelectric drive and sense structures. The demonstrated wide-angle scanning LiDAR further consists of a 905 nm eye-safe pulse laser source operating at up to 200 kHz with an optical peak output power of 30 W as well as a one-dimensional SPAD based detector with 2x192 channels. Together this leads to high density and high resolution point clouds using just a single laser, detector and MEMS scanner.