A computed tomography (CT) imaging system and method, wherein the system includes an x-ray source that is operable to emit a beam of x-rays from a focal spot and move a spot position of the focal spot. The system also includes a detector assembly that is configured to detect the x-rays attenuated by the object. At least one processing unit is configured to execute programmed instructions stored in memory. The at least one processing unit is configured to direct the x-ray source to emit different beams of the x-rays at different energy levels and to receive data from the detector assembly that are representative of detection of the x-rays emitted at the different energy levels. The at least one processing unit is also configured to direct the x-ray source to move the focal spot such that the focal spot is at different spot positions while the different beams are emitted.
