Patent ID: 7088800

Claim:
An X-ray CT system in which an X-ray detector having multiple channels is used to acquire projection information, which is provided by an X-ray beam having passed through a scan field, as a plurality of views from plural directions, and projection information detected on each of the channels is corrected in terms of a beam-hardening effect, comprising: a correction coefficient producing device for acquiring projection information from a phantom disposed in the scan field, and calculating a correction coefficient, which is used for correction, from the projection information; a correction coefficient modifying device for modifying a second correction coefficient, which said correction coefficient producing device calculates using projection information acquired from a second phantom larger than a first phantom, using a first correction coefficient which said correction coefficient producing device calculates using projection information acquired from said first phantom; and a correcting device for correcting projection information, which is acquired from a subject positioned in the scan field, using the first correction coefficient and the modified second correction coefficient.