| 摘要 |
PURPOSE:To assure a long service life of the subject laser device by disposing a conductive material highly resistant to sputtering on the edges of transparent holes provided through a cathode and employing a nickel or a nickel alloy as a cathode material. CONSTITUTION:For a hollow cathode 3 provided coaxially with a laser tube 1, there is employed nickel or nickel alloy, e.g., Inconel. A material 14, which is electrically conductive and resistant to sputtering, is disposed annularly along the edges of transparent holes 4 through the hollow cathode 3 corresponding to respective main anodes 6. He atoms and He ions excited in a bore 11 interact with Cd atoms to produce a population inversion distribution between lasing levels of a Cd ion for the onset of lasing. Thereupon, the Inconel as a cathode material has a high work function and is liable to make alloy with Cd. Accordingly, when the inner wall of the bore 11 through the cathode is exposed to the atmosphere of Cd vapor, the Inconel produces an alloy with Cd on the inner wall of the bore 11. The resulting alloy is highly resistant to sputtering. Thus, less sputtering product is formed, without being deposited in the bore 11, thereby assuring a long service life of the laser tube. |
