Conebeam X-ray computed tomography with an offset detector array

Conventional X-ray computed tomography (CT) imaging is based on the assumption that the entire cross-section of an object is illuminated with X-rays at each view angle. When imaging a large object, a large detector array is thus needed. As an alternative, we propose to offset a normal sized detector array such that slightly more than one half of the required projection data is acquired. During reconstruction, the missing data is accounted for by means of an interpolation and weighting scheme. This algorithmic approach for extending the field of view, which we here present in the context of the popular Feldkamp algorithm, is simple but effective. Supportive experimental results are provided based on simulated phantom data as well as real data obtained from a MicroCAT^TM which is a circular orbit microCT system for small animal imaging.