| 摘要 |
PURPOSE:To stabilize a laser output by providing a light-receiving element for receiving a laser beam reflected by a beam splitter and by providing in a power source a circuit for controlling a current flowing through a solenoid coil on the basis of a signal from the light-receiving element. CONSTITUTION:Based on an output signal of a light-receiving element 8, a control circuit 10 for controlling a current flowing through a solenoid coil 9, which is disposed in a power source, controls an output value by a discharge current in an Ar laser, for instance. In the case when a laser output value is varied due to some cause, the variation is detected by a beam splitter 5 and the light-receiving element 8, and when a laser output turns lower than a prescribed value, the current flowing through the solenoid coil 9 is increased so that the output is restored to the prescribed output value. Thereby the intensity of a magnetic field is increased and the output value is raised. When the laser output increases, on the other hand, the current is reduced to execute a control so as to lower the output to the prescribed output value. By this method, the output value can be maintained at a prescribed level. |
