Exact regional reconstruction of longitudinally-unbounded objects using a circle-and-line cone beam tomographic system

摘要

In a computed tomography imaging system, wherein a longitudinally- unbounded object is oriented with respect to a source of cone beam radiation and a detector array, a method is provided for reconstructing an image of the longitudinally-unbounded object. Initially, relative movement between a longitudinally-unbounded object and the cone beam source is established along at least one circular scan path and at least one linear component. The cone beam is operated to irradiate measurable regions of the object while a prescribed orbit is traversed, to project an image of the longitudinally-unbounded object as cone beam data, onto the detector array. A scan field of view is defined, relative to the cone beam geometry. An error propagation distance in a Z direction is determined for the scan. The definition of the scan field of view is then modified, according to error propagation distance, and a set of image reconstruction data is generated, within the modified field of view, from the circular and linear scan paths.