Highly Transparent Broadband and Polarization-Insensitive Absorber Based on Metasurface

Abstract

A highly transparent polarization-insensitive metamaterial absorber with wideband microwave absorption is presented. The broadband absorption (6.0~16.7 GHz, absorptance > 85%) is achieved using three patterned resistive metasurfaces. The visible light transmittance of the absorber is as high as 85.7%. The thickness of the absorber is 4.42 mm, which is only 0.088 times of the upper-cutoff wavelength. A prototype sample is fabricated and measured to demonstrate its excellent performance. The experimental results agree well with the simulation results. In view of its wide band absorption, high transmittance, low profile, polarization insensitivity and wide incidence angle stability, the presented absorber has a wide range of potential applications.

Design of an optically-transparent ultra-broadband microwave absorber

“…The data shows that the absorption bandwidth of our OT-UBA structure has an absolute advantage with almost the same relative thickness. The literature [19,22,23] pays more attention to the light transmittance and does not obtain a wider absorption bandwidth. Compared to bandwidth-conscious work, [17,24] our work extends the absorption bandwidth to 157% at a transmittance level of 60%.…”

“…The cockpit of the low-detectable aircraft, the glass window of the ground vehicle instrument in the military field and the signal-shielding microwave technology room in the civilian field require a visible light-transparent absorber to meet the engineering needs of radar cross section (RCS) reduction and electromagnetic radiation resistance, also high light transmittance to provide the operator with clear vision. Existing literature research on transparent absorbers, in which indium tin oxide (ITO), [1] graphene, [2] metal grids [3] and other materials [4,5] are used as loss layers. Not only the lighttransmitting properties, but also the electrical conductivity of the material should be considered in the impedance-matching problem.…”

Flexible dielectric spacer with tunable dielectric properties for metamaterial absorber application

“…Interestingly, the middle dielectric spacer (MDS) layer, which is critical in determining the overall stiffness and mechanical strength of the structure, has received little attention in terms of tuning the EM response or enhancing the mechanical properties of the MMA. Commercially available dielectric sheets like FR-4, glass, PMMA, rohacell foam, air, etc., suffer many limitations and result in MMA structures that are only suited for lab demonstration or interior applications [9][10][11][12][13]. For instance, employing FR-4, glass, or PMMA sheet as an MDS layer leads to mechanically rigid MMA structures restricted only to non-conformal surfaces.…”

Frequency Selective Surface for Ultra-Wide Band Filtering and Shielding

“…Such functionalities are analog to the radomes one, which allows the antenna to communicate at the operational frequency while stopping unwanted signals. Angle independence and polarization insensitivity of the frequency response to incident electromagnetic waves are required for these kinds of applications [3]. Other more specific applications have also been reported, as for example in imaging [4] or in remote sensing in [5].…”