Multi-source ct systems and pre-reconstruction inversion methods

Abstract

A computed tomography scanner has multiple radiation sources or source arrays, in specific geometric dimensions for optimized imaging speed. A CT system with maximum fan-angle Γ and K simultaneously active x-ray sources distributed over an angle of π−2Γ radians, the sources partially overlapping on a detector array, measures summed projection data corresponding to K or less line-integrals at each detector element. When the CT machine's dimensions R, R, and R, corresponding respectively to the measurement field-of-view, detector distance from iso-center, and source distance from iso-center, are such that projections of the two extreme radiation sources do not overlap on the detector, the individual line-integrals can be recovered by inversion of linear systems comprising K or less rows in fewer unknown than rows; the unknowns given by the exponential of the negative of the line integrals to be recovered. The CT scanner then reconstructs an image from the line-integral estimates.