| 摘要 |
PURPOSE:To equalize the intensity distribution of fradiation by providing the radiation source comprising an annular member which is arranged around the rotary axis of a sensor so as to cross the slicing plane of a positron CT apparatus has a specified configuration and sizes. CONSTITUTION:The annular member 11 is formed by winding a hollow pipe comprising a material which can excellently pass radiation in a coil shape with the same diameter. The diameter of the hole of the pipe and the spacing of the holes are formed so that their sizes are smaller than the intrinsic resolution of a radiation sensor of the apparatus employed. The pipe is held by a supporting plate 12 so that the spacing between the hollow parts can be maintained to be the above mentioned size. Pipe joints are fixed to both ends of the annular member 11, and the pipe 13 is connected to them. The annular member 11 is attached to the sensor comprising a ring detector 15 which is rotated around the shaft A, by the supporting plate 12. The pipe 13 is connected to a supplying means of fluid containing radioactive nuclides, and said fluid is circulated in the hollow part. In this constitution, the radioactive nuclides are uniformly distributed in a cylindrical surface shape when they are observed from the radiation sensor. |
