| 摘要 |
PURPOSE:To obtain stable operation for a long period, by automatically supplying the adequate quantity of gas when gas in a laser tube decreases. CONSTITUTION:The continuous operation of laser tube 2 causes the reduction of sealed rare gas in the tube and, in consequence, anode voltage EB of the laser tube decreases. Then, when it becomes less than reference voltage Es for the comparision by comparator amplifier 12, alarm circuit 13 is operated and the timer circuit makes electromagnetic valve 8 operate for a certain time, thereby supplying the fixed quantity of gas. This supply operation is repeated until the positive output of comparator amplifier 12 changes into negative one. |
