| 摘要 |
PROBLEM TO BE SOLVED: To provide an X-ray CT system unnecessary to move a center-of-rotation axis projecting position calibrating fixture by an operator even if the positioning of the calibrating fixture is bad and the X-ray projection data of the wire thereof is not obtained over 360°and capable of calibrating a center-of-rotation projecting position with respect to each axis without using a fixture, which is finished in the position of the wire especially with high precision, as the calibrating fixture. SOLUTION: When the projection data of the wire Jw of the center-of-rotation axis projecting position calibrating fixture Jc obtained by rotating a turntable 3 is not obtained over 360°, the already obtained data is allowed to approximate by a torigonometric function and the amplitude center and phase thereof are calculated to approximately calculate the position of a center-of-rotation axis R while a stage 5 is moved on the basis of the calculation result to allow the wire Jw to approach the center-of-rotation axis R and the projection data of the wire Jw is employed by subsequently again rotating the turntable 3. By this constitution, the wire Jw can be set at a position where the projection data over 360°is automatically obtained without positioning the calibrating fixture by the operator. COPYRIGHT: (C)2008,JPO&INPIT
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