Optimization of deformation shape of an active electro-optical focusing device

Severe deformation which was induced by internal (residual) stress was observed on the MOEMS focusing device without driving voltage. Based on beam suspended membrane, FEM software COMSOL Multiphysics was used to predict the deformation induced by internal stress, model parameters (beam width and length), boundary condition of the chip. Found the parameters which can make the membrane be relative flat initially. Expanded the model including ring shaped electrode, using COMSOL coupled fields(AC/DC-Electrostatics module, Structural Mechanics-Solid Mechanics module and Mathematics-Deformed Mesh-Moving Mesh module), found the inner radius of ring shaped electrode which can get perfect parabolic shape of membrane with large maximum relative deflection under driving voltage.