| 摘要 |
PURPOSE:To increase creeping withstand voltage on the inner surface of an enclosure and reduce its size by providing a glass screening cylinder whose inner wall surface is covered with a metal coat, around the space where cathode and anode are facing each other including its peripheral area. CONSTITUTION:A cathode terminal 3 in which a cathode 2 is mounted on both ends of an enclosure 1 made of glass, or the like and an anode terminal 5 on which an anode cylinder 4 is mounted are provided. The electron flow from a filament 6 strikes a target 6 and the radiated x rays in this case are taken out from a radiating win dow 9. Besides, an intermediate metal fitting 11 is mounted on the anode terminal 2 and a glass screening cylinder 10 with metal coating applied to its inner face is further fixed to it so that the enclosure 1 and the cathode 2 can be fully spaced and the space where a cathode and anode are facing each other, can be screened from the enclosure 1. As a result, even when the enclosure 1 is a short and small tube, creeping discharge can be prevented from occurring on the inner surface of the enclosure 1. Besides, its dielectric strength can be improved and its size be reduced. |
