How MMDM works?

MMDM consists of a thin (500 to 700nm thick) membrane made of silicon nitride. The membrane is coated by a thin layer of aluminum or gold to produce a highly reflective surface. The membrane is fixed to silicon frame and suspended over a number of planar electrodes - electrostatic actuators. When the membrane is electrically grounded and a voltage is applied to one or a number of the actuators, the membrane is deformed locally changing its shape. Combinations of voltages applied to different electrodes form different shapes.