Reconfigurable Far-Infrared FSS Filters on Polyimide Substrate

Abstract

We present a novel electrically scalable, reconfigurable frequency selective surface (FSS) far-IR filter fabricated on transparent, and flexible polyimide substrate. Our proposed method of reconfigurabilty is achieved by employing phase change materials (PCMs). The PCM primarily considered in this proposal is vanadium dioxide (VO₂) due to its relatively low temperature reversible metal to insulator transition and conformity to common fabrication techniques. Here, the proposed reconfigurable filter covers 15–17 μm with a stopband center wavelength that can switch between 15.5 and 16.1 μm with the activation of VO₂. Although the design provided is intended for the far-infrared, it can easily be scaled to meet the needs of longer wavelength and lower frequency applications.