| 摘要 |
PURPOSE:To improve uniformity of glow discharge for ignition and to enhance laser output, by forming divided electrodes of a cathode into SIGMA shape while providing a fine projection at the center thereof. CONSTITUTION:Glow discharge caused by applying a high voltage to a cathode 5 gives energy by which CO2 molecules are excited and laser light 12 is outputted from an optical resonator 8a. If a high voltage is applied to the cathode 5 under a reduced gas pressure, glow discharge is caused initially at the tip end of each fine projection 13 and as the gas pressure as well as the voltage is increased the glow discharge is extended quickly from the fine projection 13 to a whole SIGMA-shaped cathode pins. Then, when current of the glow discharge 11 is decreased, negative glow is translated from a part 5a to the fine projection 13 through a part 5b, Thus, discharge is always held at the fine projection 13. In this manner, uniformity of discharge is improved and enhanced laser output can be obtained. |
