| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the precision and reliability of laser output waveform control and to improve the start characteristic of laser output. SOLUTION: When IGBT 32 is turned on, a current from a laser power part 102 is supplied to the excitation lamp 20 of a laser oscillation part 100 through a switching element 32. The excitation lamp 20 is lighted and a laser light beam LB is oscillated and outputted. A switching control with 50 sets a laser output measuring value signal SL from a laser output measuring part 38 to be a main feedback signal, and sets the AC amount SPc (SIc) of a lamp power measurement value signal SP from a power arithmetic circuit 44 or a lamp current measurement value signal SI from a current measurement circuit 46 to be an auxiliary feed back signal for correction. The feedback signals SL and SPc (SIc) are compared with a reference signal Sref having a desired pulse waveform and a comparison error is obtained. The switching control signal SW of a PWM system is generated so that the comparison error becomes zero. Then, IGBT 32 is switching-controlled through a driving circuit 52 by the switching control signal SW.</p> |
