A Comparison of three Novel Optical Wavelength Filters with Cascaded Directional Couplers

Abstract

We compare three novel structures of optical wavelength filters. They are composed of cascaded directional couplers. The improved filtering devices have narrower lateral widths and occupy smaller areas than our original design. And their optical characteristics and performances are analyzed by the finite difference beam propagation method employing the Runge-Kutta method (RKBPM). The simulation results shows that these new types of filters have better suppression of lightwave components at short wavelengths.