Reconstruction algorithm for the circular orbit cone-beam scan 3D-CT with line-focus source

FDK three-dimensional computed tomography (3D-CT) reconstruction algorithm for the circular orbit cone-beam scan with the point-shaped X-ray source is more widely accepted when compared with other types. It has high reconstruction speed and accuracy within cone-beam angle of 10°. However, this algorithm does not apply for circular orbit cone-beam scan with line-focus X-ray source. So the FDK approximation principle of the point-focus X-ray source is extended to line-focus X-ray sources. An algorithm for the reconstruction of circular orbit cone-beam scan to the line-focus X-ray source was deduced. Computer simulation results prove the validity of the algorithm. Using the experimental data of circular orbit cone-beam large-field-of-view scan, the reconstruction algorithm creates the right images.