An optically transparent flexible metasurface absorber with broadband radar absorption and low infrared emissivity

Abstract

The rapid development of surveillance technology has driven the research of multispectral stealth. Demand for infrared and microwave radar compatible stealth is becoming increasingly urgent in military applications. Herein, a versatile metamaterial absorber is designed and fabricated to simultaneously achieve ultra-broadband radar scattering reduction, low infrared emission, and high optical transparency. The designed structure consists of an infrared stealth layer, radar absorption layers, and backing ground. The infrared stealth layer employs specifically indium tin oxide (ITO) square patches, while the radar absorption layers can be obtained by stacking different size ITO patterned films of the same structure with high surface resistances, realizing broadband microwave stealth performance in the 1.98 to 18.6 GHz frequency range with an incident angle of 45º. The broad radar stealth and low infrared emissivity of 0.283 are consistent with the simulations and calculations. Furthermore, the designed structure exhibits characteristics such as polarization insensitivity, wide incident angles, optical transparency, and flexibility, allowing for a wide range of applications in various environments.

Transparent and Ultra-Thin Flexible Checkerboard Metasurface for Radar–Infrared Bi-Stealth

“…It can be found that the IR radiation of the checkerboard metasurface is higher than the metal plate, but is significantly lower than PET, which confirms the good IR stealth performance of the metasurface. Based on the imaging results, it can be estimated that the IR emissivity of the checkerboard metasurface is as follows [ 39 ]: where is the temperature displayed in the IR image, is the ambient temperature of the metasurface, and is the atmospheric temperature. The ambient temperature is 50 °C, the atmospheric temperature is 25 °C, and the checkerboard metasurface in Figure 13 c shows a temperature of about 32 °C.…”

“…It can be found that the IR radiation of the checkerboard metasurface is higher than the metal plate, but is significantly lower than PET, which confirms the good IR stealth performance of the metasurface. Based on the imaging results, it can be estimated that the IR emissivity of the checkerboard metasurface is as follows [39]:…”

An Optically Transparent Metamaterial Absorber with Tunable Absorption Bandwidth and Low Infrared Emissivity

“…The differences in the IR emissivity at different positions in Figure 9b,c were caused by inhomogeneous heating. The IR emissivity of the IRSL can be approximately estimated by [42] e IRSL = (T…”