| 摘要 |
PURPOSE:To always obtain a stable linear beam by providing expansion bellows at the mounting mount section of a filament and adjusting the relative positional relationship of a linear filament and a grid while they are being irradiated with an electron beam. CONSTITUTION:A flange 21 is provided on the upper end of an insulator 6 and bellows 22 are mounted at the lower part in the airtight holding welding structure. The lower end of the bellows 22 is also mounted airtightly on a separate flange 23. Then, by adjusting a height adjusting screw mechanism 24, the position of a filament 3 can be adjusted tridimensionally for the slit position of a grid 2'. As a result, since the profile can be monitored and corrected realtime while it is being irradiated with an electron beam, the uniformity of the current density distribution of a linear electron beam and such can always be held. |
