| 摘要 |
<p>An X-ray examining device comprises an aperture consisting of sector-like laminations instead of a commonly used iris aperture. The laminations are rotatable about axes perpendicularly to the main axis of the beam to be stopped, and the sides of the laminations are adapted to the optical system so that proper imaging is maintained also in the case of a comparatively small passage opening of the aperture.</p> |
