| 摘要 |
PURPOSE:To establish stabilization of emission characteristic by forming in the structure with high efficiency of heating by high frequency inductive heating from the outer circumference, a first grid electrode arranged at the shortest distance from a among various grid electrodes constituting an electron gun assembly. CONSTITUTION:The first grid electrode 3 out of the 1st-4th grid electrodes 3-6 arranged sequentially within the neck tube 1 along the axial direction of the tube has the outline of approximately rectangular configuration and there is provided a conductive wire 8 in the space between two opposite edges constituting the major edges and the inside face of the neck tube 1. Therefore, because when the electron gun assembly is heated with high frequency, the ring-shaped current passage is formed, more large current is generated and resultantly, discharging of gas can be effectively achieved by concentrically heating the first grid electrode 3. |
