Dr. Youmin Wang is a Postdoctoral Scholar with a primary focus on optical MEMS-based beamsteering devices. He earned his Ph.D. from the University of Texas at Austin in 2013, where he conducted research in microelectromechanical systems, various imaging modalities, and biomedical microdevices. He received his B.E. in Electrical Engineering from Shanghai Jiao Tong University in 2008.
MEMS-Actuated Grating-based Optical Phased Array for LIDAR [BPN788]
We aim to integrate the OPA MEMS system into the application of automobile navigation, which is currently primarily dominated by opto-mechanical scanning based systems. Opto-mechanical scanning devices are usually bulky and relatively slow, and cannot provide the steering speeds and versatility necessary for many applications. In drawing from phased array concepts that revolutionized RADAR technology by providing a compact, agile alternative to mechanically steered technology, the OPA based LIDAR program seeks to integrate thousands of closely packed optical emitting facets, precise relative electronic phase control of these facets, and all within a very small form factor. Comparing with other competing LIDAR system, the OPA based LIDAR system will have multiple degrees of freedom for phase control which enables not only agile beam steering but also beam forming and multiple beam generation, greatly expanding the diversity of applications. Traditional optical phased arrays (OPA) are made of liquid crystal phase shifters, piston mirrors, and optical waveguide arrays. The liquid crystal OPA has slow response time. MEMS OPA with piston mirrors has fast response time. However, realization of OPA with large field of view is challenging because it requires small pitch in the phased array. Recently, it was reported that optical phase shift is controlled by moving a grating element in the lateral direction. However, the widths of the phase shifters are limited by the size of the actuators. In this project, the actuators are integrated underneath the diffractive elements so OPA with high fill factor and small pitch can be realized. Such OPA will have large field of view and high optical efficiency.