Analysis and optimization for effective diffraction area of grating movable light modulator

GMLM (Grating Movable Light Modulator)is a novel light modulator based on MOEMS technology which can be used in fields of display and print. But present design has only 30% effective diffraction area, which can deeply influence the key parameters such as pixel-filling-ratio and contrast. An electromechanical model of the device was established, and the effective spring constant of GMLM was deduced by energy method. According to that the relation between structure parameters and effective diffraction area was analyzed theoretically. Then optimized structures were simulated and validated by FEM software Coveter Ware. Simulation data shows that the optimization device model can enhance the effective diffraction area to about 90% from less than 30% before optimization.