Compact and innovative laser beam steering optical engine for smart glasses applications

Abstract

Smart Glasses, a subcategory of Head Mounted Display devices, are getting popular in the recent years, offering a convenient way to add information in addition to what the wearer see. Designers are seeking ways to build a Display Engine that can meet the targeted image performance (such as resolution, filed of view) yet keeping the total device size and weight as low as possible. This paper presents an innovative Display Engine based on Laser Beam Scanning (LBS) and outlines the main building blocks that were design and prototyped. It presents the use of MEMS Micro Mirrors (Resonant mirror and Linear mirror) and a newly developed RGB laser light source that integrates the three laser diodes into a single package. This paper outlines the opto-mechanical design considerations, beam and spot size analysis, the driving electronics, mirror and color control loops, the procedures and steps to assemble and calibrate the optical engine and finally presents the achieved results of this work.