High Optical Transparent Wideband Microwave Absorber

It is challenging to design a thin and optical transparent wideband microwave absorber. In this paper, the optical transmittance of the proposed absorber is effectively improved, maintaining the wideband absorption. The method of improving optical transmission is discovered, through the analysis of the absorption mechanism and the transmittance of the proposed absorber. With the 82.1% high visible light transmittance, the proposed absorber can achieve around 90% absorption in 19.2–36GHz. The thickness is only 0.07λ at the lowest operating frequency, which is close to Rozanov’s ultimate thickness. The high transparency, wideband absorption, low thickness indicate that the proposed design has the potential for a wide range of applications.