Performance Optimization of Thin Film Optical Interference Filters for Optical Communication Systems

WDM and DWDM applications require specific filter characteristics and set of optimization methods which is the core of this paper. The optimization parameters are; the layer´s structure, the indices of refraction, and their thicknesses. In this paper, methods to optimize the optical filter performance are introduced. Ripples, and width of the reflection and transmission regions for band pass filters are the main performance measures that are discussed in this paper. An optimization algorithm is implemented to enhance the ripples behavior in both sides of the high reflectance regions. Another optimization algorithm is implemented and used to widen the high reflectance zone and the simulation results are presented in this paper. Transmission region width is controlled using a special optimization algorithm that is implemented and applied in this paper. The simulation results after the rejection of one, two, or more rejection lines lay in the high transmission band are discussed.