Comparative Study of 2-DOF Micromirrors for Precision Light Manipulation

Many industry experts predict that the future of ber optic telecommunications depends on the development of all-optical components for switching of photonic signals from ber to ber throughout the networks. MEMS is a promising technology for providing all-optical switching at high speeds with signi cant cost reductions. This paper reports on the the analysis of two designs for 2-DOF electrostatically actuated MEMS micromirrors for precision controllable large optical switching arrays. The behavior of the micromirror designs is predicted by coupledeld electrostatic and modal analysis using a nite element analysis (FEA) multi-physics modeling software. The analysis indicates that the commonly used gimbal type mirror design experiences electrostatic interference and would therefore be diÆcult to precisely control for 2-DOF motion. We propose a new design approach which preserves 2-DOF actuation while minimizing electrostatic interference between the drive electrodes and the mirror. Instead of using two torsional axes, we use one actuator which combines torsional and exural DOFs. A comparative analysis of the conventional gimbal design and the one proposed in this paper is performed.