| 摘要 |
PROBLEM TO BE SOLVED: To form a proper electron beam by easily producing an electro gun cathode.SOLUTION: An electron gun cathode 104 is in the shape of a square pole and emits an electron when heated. The electron gun cathode 104 is inserted into a cylindrical recessed part 103a provided at a tip part of a truncated conical holding tool 103. A filler 120 is filled around the electron gun cathode 104 in the recessed part 103a, and the electron gun cathode 104 is held in the recessed part 103a. |
