GAS LASER OSCILLATOR

PROBLEM TO BE SOLVED: To detect arc discharge or the like between a pair of main discharge electrodes 5, 7 as well as electrode-outside discharge when a gas laser oscillator 1 is maintained and inspected in the state in which the output of a laser beam LB is lowered, and to suppress the action to attract the electrode-outside discharge of a sensor electrode 21 when laser beam machining is performed. SOLUTION: A sensor electrode 21 arranged in a chamber is constituted so that it is position-adjustable between a proximate position close to the main discharge electrodes 5, 7 and a spaced-apart position spaced apart from the main discharge electrodes 5, 7. Consequently, when the gas laser oscillator is maintained and inspected in the state in which the output of the laser beam LB is lowered, sensitivity of the sensor electrode can be enhanced by setting the sensor electrode to the proximate position, and so it is possible to detect the arc discharge or the like between the pair of main discharge electrodes as well as the electrode-outside discharge. COPYRIGHT: (C)2004,JPO&NCIPI