Dynamic Color Filtering Based on Fabry–Pérot Cavities Incorporating Vanadium Dioxide

Color filters are extensively applied in the fields of display and lighting. Although various color filters have been designed to date, very few studies have been devoted to dynamic color filtering that can enable a wealth of advanced functionalities. Herein, we demonstrate a dynamic color filter based on the optical interference of Fabry-Pérot (F-P) and actively tunable optical properties of vanadium dioxide (VO₂). The color filter is constructed by sputtering a VO₂ film on a polished Al sheet, exhibiting a continuum of customized colors depending on the VO₂ thickness. Dynamic color filtering is promoted by the insulator-metal transition (IMT) of VO₂, enabling not only the generation of two distinct color states but also the realization of continuous color modulation. Additionally, this filter exhibits tunable broadband near-perfect absorption in the visible and near-infrared regions. Upon VO₂ phase transition, the absorption peak can be modulated across a large spectral range, and the absorption intensity at a specific wavelength can be switched with a large on-off ratio, and the largest absorption contrast and modulation depth (MD) reach ∼63.1% and ∼4.8 dB, respectively. Benefiting from the dynamically tunable optical properties, a temperature perception device and wavelength-selective dynamic absorber are demonstrated, revealing the great potential of such a device for applications in color decoration, temperature sensing, adaptive optical camouflage, optical switches, etc. The structurally simple, photolithography-free, and scalable fabrication processes provide great convenience for low-cost and robust optoelectronic devices based on color filters.