Comparisons of the Straight Torsion Beam and Folded Torsion Beam Designs for MEMS Micromirrors

The torsion beam design for the micromirrors has an important effect on electrostatic behavior. We investigated three torsion beam designs and determined their effect on electrostatic characteristics as well as resonant frequency. The first design is straight torsion beam, which is the simplest and most commonly used. The second and third designs, add different folded structure to improve the performance. The results suggest that the folded-beam design has a significant effect on actuation performance. The most effective design had a driving voltage approximately one half of that for the simplest design, and the effect on resonant frequency is slightly more modest but still impressive.