| 摘要 |
A light amplifier which is capable of stably outputting laser pulses from the first pulse and a laser processing device are provided. A laser processing device 100 includes a light amplifying fiber 1, a seed LD 2 for pulsing seed light for plural times during an emission period, an excitation LD 3 for generating the exciting light of power at a first level during a non-emission period which is immediately before the emission period and generating the exciting light of power at a second level which is higher than the first level during the emission period, a light receiving element 15 and a peak value detector 16 for detecting power of an output light pulse which is output from the light amplifying fiber, and a control device 20. The control device 20 controls the power (a bias current of a driver 22) of the exciting light of the non-emission period based on the detected value from the peak value detector to cause the power of first output light pulses which are generated during the emission period to be the same as the power of final output light pulses. |
