LASER APPARATUS

PURPOSE:To detect the exchange period of a lamp properly by outputting a lamp exchange signal when the quantity of compensation to compensate the output drop by energizing a laser power unit. CONSTITUTION:This device is equipped with a laser power unit 7 which gets the laser output by exciting laser medium by a lamp. This power unit 7 is equipped with a laser head unit 7n which monitors laser output. A CPU unit 5 is provided as a main controller which detects the output drop of a laser beam based on the monitor signal 2 outputted from this laser head unit 1 and compensates the amount of the output drop by energizing the laser unit 7. And, in the case that the quantity of compensation exceeds a specified quantity, a CPU unit 5 outputs a lamp exchange signal to inform the lamp exchange period, that is, an alarm signal 8.