| MEMS (Micro-electro Mechanic Systems) mirrors have had a wide application range in the last decade including projection displays, bar code reading, Optical Coherence Tomography (OCT), confocal microscopy and head up displays. There are different actuation methods used and the most common method is electrostatic actuation due to its low power consumption and low fabrication costs in large volume.;In this study, nonlinear static and dynamic behaviors of a MEMS mirror with side-wall electrodes are investigated. The purpose of using sidewall electrodes is obtaining larger scanning angle by increasing the surface area of the electrodes. A model for the MEMS mirror with sidewall electrodes has been introduced in literature, but this model was unable to predict nonlinear static or dynamic responses. An analytical model for static and dynamic responses that closely predicts the nonlinear response reported experimentally.;Nonlinear superharmonic and subharmonic resonances are captured in the frequency response analysis that fit closely with the experimentally reported secondary resonances. Through mathematical derivation, it is deduced that the quadratic nonlinearity is the dominant nonlinear stiffness caused by electrostatic excitation. The effect of increased forcing and decreased damping on triggering the secondary resonances is investigated in the frequency response. The presented investigation is valuable for predicting the performance of the MEMS mirrors used for steering and scanning in optical devices. |
