An Optically Transparent Glass Absorber using a Multi-Fractal Ring Structure for Ka-band

Abstract

An optically transparent metamaterial absorber is presented. First, a study regarding the metal mesh is conducted to understand the trade-off between its electrical and optical properties. Next, an optically transparent metamaterial absorber is designed using multiple fractal rings and 250 m-spaced metal mesh. Such structure enhances both the bandwidth and absorption for oblique incident waves. Numerical simulations indicate an absorption over the frequency range of 25.54 GHz-31.40 GHz. Moreover, a stable absorption up to 45° is ascertained for both TE and TM oblique incidences.