| 摘要 |
PURPOSE:To exactly execute monitoring in a short time by holding a detecting part at a constant temperature, irradiating it by a laser for a prescribed time, and monitoring the laser power from a rise temperature caused by the irradiation after a prescribed time. CONSTITUTION:A laser power detecting part 3 is usually held at a constant temperature through a heater 32 by a temperature controller 44. In this state, at the time of monitoring the laser power, a laser irradiation command is given to a laser generating part 1 by a timing control circuit 41, and also, by cutting off a heater 32 by a switch SW1, a temperature control is suspended. Subsequently, the detecting part 3 is irradiated by a laser for a prescribed time through a laser emitting part 2, its temperature rises, and it returns to a constant temperature after a prescribed time. Its rise temperature is detected by a temperature sensor 31, and thereafter, compared with a set value of an upper and lower limit temperature setting device 43 by a comparator 42. By an output of the sensor 31 which is varied in accordance with a result of its comparison, the laser power can be monitored. |
