A Design Approach to 2-D Electrostatic Torsional Micromirrors With Z-Axis Displacement Compensation

We report a new method for maintaining constant z-axis displacement of an electrostatic torsional micromirror driven by quadrant electrodes, by adding an additional control electrode. The voltage applied to the control electrode is theoretically related to the voltages applied to the quadrant electrodes. The mathematical model is presented and validated through finite-element analysis