Ultra-Small Laser Scanning Module with High Accuracy Alignment

Abstract

We report that an ultra-small laser scanning module of millimeter size was realized. This laser scanning module consists of silicon substrate, a laser diode array with multi-emitter, and microprisms. The microprism measures 180μm wide, 100μm high, and 80μm thick. The smaller the optical elements used, the more precise the alignment accuracy required. The microprisms and alignment pins for laser diode array are fabricated on the same silicon substrate using MEMS technology. Then the laser diode array is attached to the silicon substrate by setting with the alignment pins. The alignment accuracy was ±2.8μm for the interval between the laser diode array and microprisms. The rotational angle accuracy of each axis was within ±0.3 degrees. This high alignment accuracy has been achieved without camera.