| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a positive-electrode grounded X-ray tube apparatus which eases an electric field at a triple junction to ensure a necessary insulating strength and enables a reduction in size and weight. <P>SOLUTION: The positive-electrode grounded X-ray tube apparatus includes a metal enclosure in which a negative electrode and a positive electrode including a positive target are sealed vacuum airtightly. The metal enclosure and the positive electrode are grounded. A ceramic stem insulating the negative electrode is set opposite in parallel to the inner surface of the enclosure, and the resulting counter gap near a triple junction, at which the vacuum, the enclosure inner surface, and the ceramic stem join together, is determined to be narrower than the other part of the gap. The ceramic stem is given a stepped level difference so that the counter gap near the triple junction becomes narrower than the other part of the gap. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
