| 摘要 |
PURPOSE:To provide an accurate beam output by a method wherein a beam output is directly measured in advance and automatically controlled to a specified value, a controlled condition is recorded, the recorded value is read to perform an automatic control operation. CONSTITUTION:Laser beam from a gas discharge laser tube 1 is measured at 2, compared at 3 with the reference voltage 4, and the electric current in the laser tube 1 is controlled at 6 through a comparator 5. At this time, the cooperative switches 71 and 72 are set at the contact points a, a', a condition of the control system 6 is stored at 8. When a working operation is performed, the stored value at 8 is read and compared at 5 with a condition of the electric control system 6 to perform an automatic control. The contact points are changed over to b, b'. Thus, afterwards, a control condition made by the output meter 2 is kept to continue the working operation. With this arrangement, it is possible to provide a practical laser device having a high degree of stability. |
