| 摘要 |
An X-ray computed tomography apparatus is disclosed which includes an X-ray source for irradiating an X-ray, a main detector section for detecting the X-ray passed through a subject and a scattering ray detector for detecting its scattered component. An X-ray shield member is detachably mounted between the X-ray source and the main detector section to shield the main X-ray. The apparatus thus manufactured evaluates a ratio between an amount of scattered component incident on the main detector section when the main X-ray is shielded from the X-ray shield member and an amount of scattered component which is detected by the scattering ray detector. With this ratio placed as K, an amount of X-ray, m, to be measured is found from m=b-a/K where a denotes the scattered component detected by the scattering ray detector and b denotes an output level of the main detector section when the X-ray is not shielded. In this connection it is to be noted that, with this ratio K placed as such, the values b, a are generally given without any X-ray shield member. |
