| 摘要 |
PROBLEM TO BE SOLVED: To prevent parasitic oscillation of reflected light, by arranging a central axis of a hole of an aperture, in such a manner that the axis is shifted to the cathode side from a mechanical central axis of a discharge space part by specified amount. SOLUTION: An airtight vessel 11 in which gas laser medium is sealed is installed in a gas laser oscillator. A cathode 12 and an anode 13 which constitute main electrodes are arranged in the airtight vessel 11, separately facing with each other in the vertical direction. In the airtight vessel 11, light-casting windows 18a, 18b which are closed with hermetical structure are formed in one end part and on the other end side of a discharge space part 15, facing with each other. An aperture 21 is arranged between the window 18b and an output mirror 20. A central axis O1 of a hole 21a of the aperture 21 is arranged to be shifted, by specified dimention, to a mechanical central axis O2 of the discharge space part 15. Therefore, when the mirror of an optical resonator slightly slants and reflection light from the anode surface is generated, the oscillation output together with normally amplified laser light can be prevented, so that deterioration and instability of beam quality of laser light can be prevented. |
