Photonic structures in multispectral camouflage: From static to dynamic technologies

Ubiquitous camouflage phenomena in natural inspire and promote the development of modern camouflage technologies. Currently, the combination of detectors working across different wavebands has posed severe threats to camouflage technologies working within single/narrow wavebands, creating an urgent demand for advanced multispectral camouflage technologies. However, due to distinct or even incompatible requirements of thermal properties at different wavelengths, achieving multispectral camouflage via the same structure still remains tremendously challenging. Benefiting from the micro/nanomanufacturing technologies, various photonic structures that enable precise manipulation of electromagnetic waves emerge, and they have been successfully applied to multispectral camouflage. In contrast, a systematic review of photonic engineered structures in multispectral camouflage technologies is still lacking. Herein, we present the state-of-the-art review of advanced photonic structures in multispectral camouflage technologies. This review commences with the elucidation of spectral detection principles and corresponding requirements for multispectral camouflage, summarizes exceptional photonic structures for static infrared compatible multi-band camouflage application, continuous with innovative photonic structures integrated with dynamically reconfigurable materials for adaptive multispectral camouflage, and ultimately ends with challenges and perspectives for the future development of photonic structures in multispectral camouflage technologies. This review can serve as guidance for designing and applying photonic structures in multispectral camouflage technologies.