3D ROI imaging with a detector smaller than the imaged object

In industrial CT applications, one is often interested only in knowledge about an region of interest (ROI) within the imaged object. Furthermore, it is not uncommon that the available detector cannot form a field of view (FOV) covering the entire support of the imaged object and that the scan is achieved through the rotation of the object instead of only the source and detector. In this work, we proposed an approach to imaging an ROI using a detector with a limited size and general scanning configuration. The BPF algorithm has been generalized to reconstruct ROI images from data acquired with the configuration. Results of numerical studies demonstrate that the proposed approach can yield accurate ROI reconstruction. The approach and result may find important imaging applications in industry and security scan.