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

Abstract

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.