Three dimension imaging method based on cone beam-RT scanning mode

Since FDK reconstruction algorithm with circular orbit scan mode based on cone beam can only be used when the cone angle is small, the field of view is too narrow to scan large objects, a new reconstruction algorithm of 3D-ICT based on cone beam-RT(rotation and transverse) scanning-mode is developed. In the first step, X-ray projection data were gathered by 2-D flat panel detector for three times in the horizontal direction, accompanied with the rotation motion in every horizontal locations. Furthermore, the projection data are rebound to oblique parallel projection data. Then the data are backprojected into the 3D-reconstruction image after the data have been preweighted and filled. Simulation experiment results show that the algorithm can acquire the satisfactory image quality with wider field of view in order to scan large objects. Analysis results show that the scanning field of view along the horizon can be improved to 2.88 times compared with classic FDK algorithm.