Abstract
Efficient and accurate perception of environmental color information is pivotal in imaging technologies. However, the field currently faces technical bottlenecks such as color inaccuracy and optical energy loss. Micro-nano photonic technologies, which manipulate light fields via micro-nano structures, play a crucial role in enhancing image acquisition, improving color reproduction, increasing optical energy utilization, and promoting system miniaturization. This article systematically reviews the design principles and research progress of high-efficiency color routers based on nanophotonic structures. By comparing the physical mechanisms of nanophotonic color routers with those of traditional spectral filters, we elucidate the unique advantages and vast application potential of nanophotonic approaches. We focus on analyzing the differences in color-routing performance among metallic materials, low-refractive-index materials, high-refractive-index materials, and their two-/three-dimensional nanostructures, alo