Electromagnetic 2D scanning micromirror fabricated with 3D printed polymer parts for LiDAR applications

Abstract

In this research, an omnidirectional scanning micromirror fabricated using a three-dimensional (3D) printing process and manual assembly is presented. The core part of the scanning micromirror is printed with photoc-urable resin using vat polymerization based on digital light processing. Externally fabricated 6 mm-diameter aluminum-coated silicon mirror plate, self-supported coils, and permanent magnets were assembled with the printed part to provide a reflective surface and electromagnetic actuation. Two types of devices with different spring shapes were designed and tested. Modal analyses were performed for each model with different magnet combinations in the design phase. To optimize the 3D printing process, resin mixtures with various mixing ratios were tested. An optical scan angle of 8.98 degrees has been obtained for model #1 printed with an ABS-like resin at 309 Hz and an input current of 0.2 Arms. For model #2 printed with a 9:1 mixture of ABS-like resin and B9R-2-Black resin, an optical scan angle of 6.04 degrees at 356 Hz an input current of 0.2 Arms has been obtained. Spiral scan patterns with various modulation depths were generated using model #1.