| 摘要 |
PURPOSE:To reduce inspection time without use of any crystal lattice, by using two filters of different absorption characteristics only with energy at a K absorption terminal. CONSTITUTION:A patient 4 is irradiated entirely at one time with X-rays expanding to a certain extent via a filter 2 after reduced with a collimator 3. The X-rays transmitted are detected with a X-ray position detector 5 such as a gamma camera or X-ray TV and image data is stored in an image memory 6. A filter 2 is of two different kinds which are made respectively based on two substances with atomic number of Z and Z+1 such as cobalt and nickel while it is selected to give such a thickness that makes in the absorption coefficient equal at an energy area except for that between K absorption terminals Ek1 and Ek2 of the two substances. Image data are obtained with the filters 2 separately and a difference is determined between the two images with a data processor 7. This enables collection of image data without requiring scanning to reduce measuring time thereby achieving more efficient utilization of X-rays as compared with that by using a crystal lattice. |
