| 摘要 |
<p>A method of obtaining an axial tomogram uses a beam of radiation, particularly an X-ray beam which is directed through a slit in a plate, onto e.g. the head of an examined person, while the person is rotated about a vertical axis. This has the effect of varying the absorption of the beam, which is then received by a photographic plate which also rotates about a vertical axis. A series of photographic plates is used, so that a stack of photographs is obtained, giving a radiogram. The rotary speeds are programmed to give a correct exposure. Alternatively, the receiving surface can be a fluorescent screen, onto which the camera is focussed. Further, the position of the examined person can be fixed, and the apparatus rotated around him.</p> |
