| 摘要 |
<p>PURPOSE:To prevent oxidation of metallic part, by forming a separated silicon oxide membrane over the surface. CONSTITUTION:At an end of a cylindrical cathode tube 2 housing a heater 1 therein, a bass metal 3 is inserted, over which an oxide membrane 4 is formed. At the other end of the cathode tube 2, an inside cathode support 6 is fixed by laser welding through a strap 5. A portion of the inside cathode support 6 is fixed by laser welding to a strap 7 which is a cylindrical form concentric with the cathode tube 2, while the inside cathode support 6 itself is made of Kovar alloy. The surface of the support 6 is covered with SiO2 membrane 6a. Since oxidation of the metallic part of the electron tube can be prevented in such a way, the cost, the manufacture, and the performance of the electron tube are extensively improved.</p> |
