| 摘要 |
PROBLEM TO BE SOLVED: To accurately form a tomographic image irrespective of the shape of the z-profile of X-ray beams and the profile of sensor gain. SOLUTION: A CT system 10 includes an X-ray source 14 which emits X-ray beams 16 from a focus via an aperture in a collimator to a sensor 18 which has a plurality of sensor cells 20. The z-profile of X-ray beam 16 intersecting sensor cell 20 is decided using the shape of the X-ray beam 16, the width of the collimator aperture, and the dimensions of the focus. Using this z-profile, the effective gain of sensor cell is identified. To correct the error originating from the varying gain of sensor cell, the effective gain of sensor cell which was identified is used instead of actual gain of sensor cell. |
