Laser protection thin film compatible with multiband stealth based on metal–dielectric structure

Here, we demonstrate a multifunctional composite thin film based on metal-dielectric structure that simultaneously achieves visible transparency, infrared camouflage, and high-power laser protection. The inner side adopts an alternating stack of high- and low-refractive-index materials. Combined with a metal layer and outer dielectric layers, the structure utilizes optical interference to achieve a visible transmittance of 80.9%, while the structure achieves an emissivity as low as 5.9% primarily via metallic reflection. The dielectric multilayer composed of Ta₂O₅ and SiO₂ possesses a high laser damage threshold and continues to provide protection even after the outer layers are ablated. Under 1500 W/cm² laser irradiation for 120 s, the thin film exhibits exceptional damage resistance. This integrable solution offers significant potential for military optical windows, protection, and stealth system applications.