Testing and characterization of 360° rotating micromirrors

The out-of-plane micromirrors have proved to be a vital component of Micro-Opto-Electro-Mechanical Systems (MOEMS).These systems have been developed for wide range of applications including optical switching, beam steering and precise transmission and reception of bio-optical signals. This thesis focuses on design, test and characterization of rotating out-of-plane micromirrors. The system consists of polysilicon micro-mirror which is held at 45° angle on gear which has a rotational freedom of 360°. The mirror assembly is pushed into position using an assembling probe. Actuation of the rotating structure is accomplished via a coupled torsional ratcheting actuator (TRA). A test setup was developed for the characterization of the mirror in which the average intensity of reflected light is measured. Also, effect of TRA ratcheting events on the gear rotation is studied. A design for auto pop-up micro-mirror is discussed which allows the system to self assemble by using force from electrostatic actuator (TRA). However, the mechanism was not successfully demonstrated. Failure analysis of this design is done and alternative design with improvements is suggested.