Chameleon-Inspired Dynamically Tunable Infrared Camouflage for All-Day and Multiscenario Applications

Chameleons rapidly and intricately alter their color in response to environmental changes through the interaction of light with their two-layer structural skin. Inspired by chameleons, we propose a strategy to address the limitations of conventional infrared (IR) stealth materials, which often struggle to conceal objects in fluctuating ambient temperatures or thermally inhomogeneous backgrounds. Herein, we present a dynamically tunable IR camouflage (DTIC) device that combines a vanadium dioxide (VO2) IR digital camouflage layer with an indium tin oxide (ITO) temperature-regulating layer. The upper laser-patterned VO2 layer generates inhomogeneous IR speckle patterns and transitions from an initial emissivity of 0.83 to final values of 0.48, 0.38, and 0.28 through the metal–insulator transition (MIT) of VO2, controlled by the lower ITO layer. Alternatively, the device can sustain a uniform IR appearance when the MIT is inactive, accompanied by temperature regulation. By adapting its IR appearances to backgrounds, the DTIC device ensures a minimal radiant temperature difference of 0.8–2.2 °C between the simulated target and its surroundings over 24-h cycles across typical environments, including grassland, road, and sand. The DTIC device significantly outperforms conventional low-emissivity materials, static solutions, and individual phase-change materials, offering a versatile and effective approach to real-world IR camouflage.