A multi-energy CT imaging system and an application for the same. The multi-energy CT imaging system comprises: a radiation ray source having a flying focal spot function and generating a radiation ray used for transmission imaging； an energy spectrum filter comprising multiple filter modules, used for modulating an energy spectrum of an incident radiation ray, and generating an energy spectrum-modulated emergent radiation ray according to respective relative positions of each filter module with respect to a focus point of the radiation ray source, the emergent radiation ray irradiating an object under test； and a detector module used to receive a radiation ray signal having passed through the object under test. The invention uses the radiation ray source having the flying focal spot function, and combines an energy spectrum modulation method and static spatial energy spectrum filtering, thereby enabling fast switching between different radiation ray energy spectra, and achieving multi-energy CT imaging. In addition, the invention acquires non-sparse multi-energy CT data by improving an inter-layer sampling rate and/or an intra-layer sampling rate of a CT scanner, and performs accurate material decomposition of basis materials accordingly, thereby providing promising application prospects in the field of multi-energy CT imaging.La présente invention concerne un système d'imagerie par tomodensitométrie multi-énergie et son application. Le système d'imagerie par tomodensitométrie multi-énergie comprend : une source de rayons de rayonnement ayant une fonction de point focal volant et générant un rayon de rayonnement utilisé pour une imagerie de transmission ； un filtre de spectre d'énergie comprenant de multiples modules de filtre, utilisés pour moduler un spectre d'énergie d'un rayon de rayonnement incident, et générer un rayon de rayonnement émergent modulé par spectre d'énergie selon des positions relatives respectives de chaque module de filtre par rapport à un poi
