| 摘要 |
<p>Apparatus for examining a body by means of penetrating radiation includes a source of the radiation, disposed to irradiate the body, and detector means, responsive to the radiation, disposed to receive radiation emergent from the body. The source and detector means are scanned relative to the body, the scanning motion including a rotation of the source and detector means around the body. An attenuating mass is disposed between the source and detector means and rotates therewith so as to present substantially the same profile to the radiation when the source and detector means assume different angular positions with respect to the body.</p> |
