| 摘要 |
A chromium oxide film is formed so as to continuously connect an anode and a grid electrode, and an insulating member for insulating those electrodes. A chromium oxide film is formed so as to continuously connect a grid electrode and a grid electrode, and an insulating member for insulating those electrodes. With use of the chromium oxide films, no intermittent discharge phenomenon occurs between the insulating member and the anode, and between the insulating member and the grid electrodes. |
