Multispectral imaging combines spatial resolution with spectral discrimination, enabling accurate imaging for applications such as object recognition, precision agriculture, and medical diagnostics. Metasurfaces provide a promising platform for compact and integrated multispectral imaging systems due to their subwavelength design flexibility. Existing metasurface-based approaches typically integrate metasurfaces with CMOS detectors and reconstruct spectral information from detector-encoded responses. However, these methods often reduce effective pixel utilization and suffer from energy loss caused by spectral filtering, resulting in lower efficiency and increased computational complexity.Here, we exploit metasurface dispersion engineering in a reverse manner by intentionally enhancing chromatic dispersion. Using an inverse-design strategy, we realize a metalens that simultaneously performs spectral splitting and imaging focusing, producing wavelength-dependent focal positions along the optical axis. Multispectral imaging is achieved by translating a CCD detector to different axial locations to capture images corresponding to individual wavelengths. This approach fully utilizes detector pixels while avoiding the energy loss associated with conventional spectral filtering schemes.Experimentally, a long-wave infrared metalens operating from 8–12 μm is demonstrated, with focal lengths of 70 mm, 50.0 mm, and 41.5 mm at wavelengths of 8 μm, 10 μm, and 12 μm, respectively. Broadband spectral imaging across the 8–12 μm range is also achieved. This work experimentally demonstrates metasurface-based multispectral imaging in the long-wave infrared regime and provides a promising route toward compact, integrated, and future hyperspectral imaging systems.

Prof Shaowei He, obtained his PhD from Huazhong University of Science and Technology in 2008 and is currently employed at the School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, as an associate researcher. He has published more than 15 papers in well-known journals.