Optical and mechanical models for a variable optical attenuator using a micromirror drawbridge

In this paper, we develop optical and mechanical models of a surface micromachined variable optical attenuator (VOA) having an initial tilt angle. The proposed models are employed to compare various characteristics of the VOA such as snap-down voltage, attenuation versus driving voltage, and the rise time and the fall time based on the experimental data. In addition, the analytical models of the static and dynamic behavior of the drawbridge are verified using the results from the finite element method. We obtain reasonable accuracy between the results from the experiment and the proposed models.