| 摘要 |
PURPOSE:To ensure long life of a laser tube by making optimum a magnetic field distribution and the shape of the fine tube, and preventing the fine tube from being corroded by plasma. CONSTITUTION:A magnetic flux line 7 passing through a cathode 3 is adapted not to make contact with the cathode 3 to the utmost. The configuration of plasma is in conformity with that of the magnetic flux line 7, and hence the plasma is prevented from making contact with the fine tube 2 in the foregoing structure and magnetic field distribution. Hereby, the fine tube 2 is prevented from being corroded by the plasma to prolong the life of a laser apparatus. |
