Design procedure for a polarization- transformation filter with a genetic Algorithm

Abstract

This paper presents a design procedure for a polarization-transformation transmission filter, which is composed of a chiral multilayer. The design procedure proposed is divided into two stages. An ordinary filter and a polarization-transformation filter for the transmitted wave are designed with a non-chiral multilayer and a chiral multilayer at the first and the second stages, respectively. According to the specifications of the filters, two objective functions are defined with the transmitted and reflected powers. Applying a genetic algorithm to the maximization of the objective functions, one can obtain the optimal material parameters and thicknesses of the chiral multilayer. Numerical results are given to confirm the validity of the two-stage design procedure. It is seen from the numerical results that the proposed procedure is very effective in the optimal design of a polarization-transformation band-pass filter for the transmitted wave.