MEMS actuators for silicon micro-optical elements

Micro-actuators are critical elements in all micro-systems which require components that are not stationary. Numerous technologies have been developed in the field of MEMS to provide actuation. These devices are both surface and bulk micromachined and employ a variety of methods including electrostatics, thermal expansion and magnetism to generate forces and displacements. With the rapid growth of micro-optical system applications new actuators are required with unique characteristics. In this paper a review of common actuation technologies is presented. In addition two actuation methods, asymmetric combdrives and electrothermal vibromotors, which are well suited for optical systems are presented. Finally, the importance of control in micro-optical systems is discussed.