| 摘要 |
PROBLEM TO BE SOLVED: To prolong the operating life of a laser tube without exchanging discharge electrodes, by a method in which at least either of the cathode and the anode is provided so as to be able to rotate centering around its prescribed axis. SOLUTION: A cylindrical part 22b of a support member 22 is fixed by a part of a hermetic container 131 and an O-ring 25 in such a way that the part 22b can be rotated. Moreover, the part 22b of the member 22 is coupled with a rotary knob 26 outside of the container 131 in such a way that a cathode 132 and an anode 133 can be rotated by hand operation centering around their center axes. In the case where the amount of a charge, which passes through between the cathode 132 and the anode 133, reaches a prescribed value and the surfaces of the electrodes are roughened by a sputtering or the like, the cathode 132 and the anode 133 are rotated by the rotary knob 26 at an angle, at which the regions with the roughened surfaces of the electrodes do not become a discharge region. Thereby, the surfaces of the electrodes with the surfaces, which are not roughened, become a discharge surface, even glow discharge is continued and the operating life of a laser tube is prolonged without exchanging the cathode 132 and the anode 133. |
