초록 ▼

In an improved method and apparatus for cone-beam reconstruction, a helical cone-beam system is provided, operable in a half-scan configuration, offering volumetric imaging results superior to conventional scanning techniques at double the pitch. The projection data of successive rotation angles are

In an improved method and apparatus for cone-beam reconstruction, a helical cone-beam system is provided, operable in a half-scan configuration, offering volumetric imaging results superior to conventional scanning techniques at double the pitch. The projection data of successive rotation angles are sorted into reordered parallel projections having different spatial positions with respect to the rotating axis. The reordered projections are interpolated to generate interpolated projections having a common spatial position along the rotation axis. The interpolated projections are convolved and backprojected to provide a volumetric image of the object. The invention is applicable to a range of computed tomography applications, including medical scanning, baggage scanning, and industrial product scanning applications.

대표청구항 ▼

[ I claim:] [1.] A method of reconstructing a volumetric image of slices of an object in a computed tomography system including an energy source for projecting conical beams through the object toward a detector array of elements arranged in columns and in rows, each row arranged along a tangential d

[ I claim:] [1.] A method of reconstructing a volumetric image of slices of an object in a computed tomography system including an energy source for projecting conical beams through the object toward a detector array of elements arranged in columns and in rows, each row arranged along a tangential direction centered about the source; said source and said detector array being in a predetermined spatial relationship and at least said source rotating about a rotation axis for interrogating the object at successive rotation angles as relative movement occurs substantially along the rotation axis between said object and said source and detector array; said method comprising:at each rotation angle, sensing the beam intensity at each element of the detector array as projection data for the projection paths defined between each element and the source;reordering the projection data of successive rotation angles into reordered projections, said reordered projections being parallel with respect to a plane perpendicular to the rotation axis and having different spatial positions along the rotation axis;interpolating the reordered projections of adjacent rows to generate multiple rows of interpolated projections, each row of interpolated projections having a substantially common spatial position along the rotation axis; andbackprojecting a plurality of slices, each from multiple rows of the interpolated projections so as to generate a volumetric image of said object therefrom.