Snapshot Multispectral Imaging Based on Quasi-BIC Metasurface Array

Snapshot multispectral imaging is crucial for dynamic scene monitoring, yet existing technologies face trade-offs or complex reconstruction. Here, we propose a snapshot multispectral imaging method based on a quasi-bound state in the continuum (q-BIC) metalens array, which integrates narrowband filtering and focusing functionalities into a single metasurface device. By introducing dimerization perturbations in amorphous silicon metasurfaces, we achieve six narrowband channels with quality factors of approximately 150 within the 1.2–1.7 µm regime. Simultaneously, geometric phase modulation is employed to independently impart focusing capabilities to each channel, forming a multi-channel parallel imaging array. Experimental results demonstrate that under incoherent illumination, the array directly captures the spatial intensity distributions of a target across different narrowband channels in a single shot. The captured sub-images exhibit excellent spatial separation and minimal distortion, achieving snapshot multispectral imaging through a direct, reconstruction-free optical mechanism. Our work introduces a device-level fusion of spectral and imaging functions based on q-BIC metasurfaces, providing a new approach for developing ultra-compact, snapshot multispectral imaging chips with minimal reliance on post-processing. This technology holds broad application prospects in fields with stringent requirements for miniaturization, integration, and high-speed imaging, such as autonomous driving, industrial inspection, and handheld sensing devices.