High-speed spectral imaging via multispectral pulse illumination and temporal-spectral decoupling.

Spectral imaging (SI) faces inherent trade-offs among spatial, temporal, and spectral resolutions due to limited bandwidth. Current high-speed SI systems, relying on fast modulation or specific cameras, compromise spatial resolution or suffer high complexity and cost. This work presents a low-cost, high-speed SI scheme achieving up to 240 frames per second (fps) and even s-resolved multispectral observation. This work reveals the inherent temporal-spectral redundancy in SI videos and reports an active temporal-spectral coupling (TSC) and decoupling (TSD) strategy for high-speed SI. We established a prototype system using a snapshot SI camera and a multispectral LED array. The LEDs sequentially illuminate the scene channel by channel in one exposure for TSC acquisition. Each channel of the measurement corresponds one-to-one to an illumination moment. A transformer-based network is applied to decouple textural and spectral information from the measurement and re-couple them to reconstruct images across all channels and time instances. Experiments validated that the reported framework can successfully record s-resolved multispectral videos.