Optically transparent and infrared tunable flexible camouflage device
Mikyung Lim, Hyeon‐Don Kim, Hyung Cheoul Shim, Kwang‐Seop Kim, Byeong‐Seon An, Jae‐Hyun Kim
Abstract
Dynamic thermal camouflage is an emerging technology that adjusts the thermal radiation emitted by the surface of an object to match that emitted by the surroundings. Although multilayered graphene effectively modulates the surface emissivity with low power consumption, its opacity hinders its application in independent camouflage across the visible and infrared (IR) spectra. In this study, we demonstrate a novel flexible graphene-based camouflage device that dynamically controls emissivity while preserving optical transparency in the visible range. By introducing a composite structure comprising 12 layers of graphene on a flexible dielectric substrate, we achieved over 70% optical transparency with spectral and average emissivity modulation ranges of 0.42 and 0.27, respectively, while using minimal power ( ∼ 120 μ W/cm 2 ). Furthermore, the ease of patterning the graphene layers enables the creation of various IR patterns that respond to changes in the applied voltage while maintaining optical transparency. This study paves the way for advanced camouflage technology and information distortion by enabling the transmission of distinct signals across visible and IR spectra. • A novel, flexible graphene-based camouflage device is designed and validated. • The device modulates infrared emissivity while preserving optical transparency. • Spectral emissivity control of up to 0.42 is achieved with minimal power consumption. • Independent signals in the visible and infrared spectra are demonstrated.