| 摘要 |
PURPOSE:To stabilize a discharge between discharge electrodes by a method wherein a gas injecting adaptor is connected to a preliminary excitation electrode and laser gas is injected into the preliminary excitation electrode from the gas injecting adaptor. CONSTITUTION:A preliminary excitation electrode 6 is composed of a conductor 7 and an insulator 9 which is made of glass or the like and covers the conductor 7. The one end of the electrode 6 is connected to a grounding line and the insulator 9 at the other end is opened. The opened part is connected to a gas injecting adaptor 4 provided closely to a cathode 1. Laser gas supplied to the gas injecting adaptor 4 from a gas inlet 5 is introduced into the insulator 9 from the opened part of the insulator 9 of the preliminary excitation electrode 6. As a result, the air and deteriorated gas inside the preliminary excitation electrode 6 can be exhausted and the fresh laser gas can be always supplied into the preliminary excitation electrode 6. With this constitution, a stable discharge can be induced between an anode 2 and the cathode 1. |
