| 摘要 |
<p>A collimator to limit a beam of energetic rays from a point source impinging on a processable object, especially for stereotactic conformational irradiation of tumors, comprises a scanning device having a drive and an iris diaphragm with at least three leaves (6,6',6") with adjoining side surfaces (10) enclosing equal angles (alpha ) and forming a radiation-limiting opening (12). A pushing movement (13) along the side surfaces takes place through a highest to a lesser number of diaphragm leaves.</p> |
