Investigation of performance of metal-dielectric thin film optical filters

In this study, the reflection behavior of multilayer thin film optical filter models with special sequences are investigated and effects of material type, material thickness, number of layers, angle of incidence of electromagnetic wave, usage of defect layer, temperature change and different metals on this behavior were evaluated. Transfer Matrix Method is used to examine the reflection results and this method is implemented with MATLAB program. For the first time, multilayer structures are modeled with Gray code sequences and Binomial Series, and the number of reflection bands and total bandwidth values are examined. Two dimensional cylindrical multilayer structures are also examined by using Transfer Matrix Method which is connected to cylindrical wave equation. Unlike planar structures, the effect of the initial radius and number of azimuth modes due to the Bessel and Weber functions found in the equations in the Transfer Matrix Method solutions is also investigated. The results of the filter structures obtained from reflection graphs are interpreted and the study is concluded.