Modelling and Characterization of diffractive optical propagation inside MEMS variable optical attenuator

摘要

Power management is an increasingly concerned issue in all-optical network, where the continuous adjustment of the transmitted power is required. In this paper, the diffractive optical propagation inside a magnetic actuated, surface micromachined variable optical attenuator has been modeled and characterized. The modeling of the diffractive optical propagation is based on a gaussian beam approximation to the fiber mode, a calculation of the free space diffraction past a square aperture based on the Fresnel-Kirkhoff diffraction integral, and the mode-overlap integral between the diffracted beam and the fiber mode. The fabrication of the attenuator is based on the nonsilicon surface micromachine technology. The experimental data is in good agreement with the theoretical calculation result. Based on the work, a variable optical attenuator (VOA) has been successfully developed.