BEAM HARDENING POST-PROCESSING METHOD AND X-RAY CT SCANNER

摘要

PROBLEM TO BE SOLVED: To provide a beam hardening post-processing method and an X-ray CT scanner that can simply make the correction of a BH effect for each channel precise and in consideration of a nonlinear effect.;SOLUTION: Projection information in which the transmission length of an X-ray beam is different for each view is obtained by arranging phantoms with different diameters in positions displaced from the center of imaging (Step S501). Consequently, projection information whose projection information value is different for each view is obtained in each channel and a correction coefficient is obtained (Step S506). From the correction coefficient, a correction function including also a nonlinear effect is obtained by the fitting of a high-order function (Step S508). As the result, the correction of the projection information value for each channel performed after the BH correction permits a high-precision correction and a high-precision correction even by a few pieces of phantom projection information. Thus the time burden of a calibration can be reduced.;COPYRIGHT: (C)2004,JPO&NCIPI