CONE BEAM SCANNING TRAJECTORIES FOR THREE-DIMENSIONAL COMPUTERIZED TOMOGRAPHY DATA ACQUISITION WHERE OBJECT IS LARGER THAN THE FIELD OF VIEW

摘要

the invention relates to a configuration of a three-dimensional tomographic imaging systems, computer type cone beam scanning, which makes it possible to minimize the missing data in the set of information and at the same time, the altu00e9rat. ion of data and the occurrence of artifacts.when the image representation is only a part of the object (58), which has an axial extent greater than the visual field of the optical system (50) is cylindrical.at least two pathways are formed by circular source scanning, centered on a rotation axis (52) positioned respectively in two terminals (54, 56) plans, defining the axial extent of the visual field.at least one cone beam x-ray source (60) and at least one two-dimensional matrix detector (62) which is used to scan the object in the scan paths (80) of the source, while the acquisition of the projection data of the beams only from the conical beams which pass through the visual field of the system.preferably, at least one additional source of circular scanning trajectory is formed centered on the axis of rotation (52) and placed in an intermediate level for both terminals.