Perfect adaptive infrared camouflage for complex temperature fields

Infrared camouflage is essential in applications exposed to dynamic and complex thermal environments, particularly in military and industrial settings. Conventional static infrared camouflage methods are limited by their fixed emissivity, which is unsuitable for rapidly changing temperature fields. This study presents a metamaterial-based adaptive infrared camouflage film that utilizes polytetrafluoroethylene (PTFE) as a thermally responsive layer. The thickness of the PTFE layer varies with temperature, enabling dynamic modulation of the metamaterial's structural parameters. The metal-dielectric-metal (MDM) structure is designed to couple incident light and actively adjust the material's emissivity, thus achieving effective concealment in infrared imaging. Results demonstrate that at the wavelength of 12.4 μm, the material's emissivity peaks at 0.97 at 0 °C and decreases to 0.05 at 200 °C while maintaining a stable radiative output across the 8–13 μm band despite temperature fluctuations. Within the 0-200 °C range, the metamaterial exhibits maximum and minimum radiant power values of 50.76 W/m 2 and 33.55 W/m 2 , respectively, with an average of 41.07 W/m 2 - closely matching the ideal infrared camouflage requirement of 46.61 W/m 2 . Therefore, this approach enables passive adaptation to complex thermal gradients, providing a superior solution for adaptive infrared camouflage with significant potential for both military and civilian infrared concealment applications.