| 摘要 |
PURPOSE:To perform effective heating degrassing by providing a means which directly heating a pipe that maintains an electron beam path in vacuum. CONSTITUTION:The heating degassing within a lens body is performed by providing a heating means made of a stainless pipe 5 without using the heat generation of the excitation coil of an electron lens. The stainless pipe 5 can be heated by a heater 13. This can effectively heating-vacuum-degrassing the whole part of the lens body, balancing the temperature in the stainless pipe 5, the upper spacer 6, and the lower spacer 9 by jointly using the heating of the excitation coil of the elctron lens. |
