| 摘要 |
PURPOSE:To prevent the generation of the eccentricity and the bend due to an external vibration of the cathode of a coaxial type cold cathode gas laser tube using the cylindrical cathode by providing a tapered portion at which the cathode is in close contact with a vacuum envelope and an end central recess for accommodating and holding one end portion of a laser capillary tube. CONSTITUTION:A gas laser tube is provided with a vacuum envelope 1 with one end portion of its inner circumferential surface tapered toward the end portion on the cathode side. A cylindrical cathode 3 has a tapered portion 21 fit in the envelope 1 in close contact therewith, a cylindrical portion 23 extending from the tapered portion 21 and a side end portion central recess 25 for accommodating and holding one end portion of a laser capillary tube 5. On the other hand, the laser capillary tube 5 has a discharge blowout port 27 and is fixedly supported by a laser capillary tube junction 13 on the anode side and the end portion central recess 15 on the cathode side. This structure enables the gas laser tube 5 to be surely held by the reaction force due to the elastic deformation of the central recess 25 in assembling the laser tube. Accordingly, the change in an output due to the rotation of the gas laser tube, the change in a beam and the change in an output due to vibration and shock are removed. |
