METHOD FOR MEASURING DETERIORATION STATE OF OUTPUT MIRROR IN LASER OSCILLATOR, AND LASER PROCESSING APPARATUS

摘要

Provided is a laser processing apparatus which performs processing by using a laser beam (4) outputted from a laser oscillator (1). The laser processing apparatus is provided with an aperture (5), which is arranged on an optical path of the laser beam (4) outputted from the laser oscillator (1), blocks the peripheral portion of the laser beam (4) and passes through the center portion; and a beam power measuring sensor (6) for measuring the beam power of the laser beam (20) passed through the aperture (5). When the output mirror of the laser oscillator (1) is in a high heat loaded state due to a laser beam having a high beam power, deterioration status of the output mirror (2) is judged by using the fact that the beam power of the laser beam passing through the aperture (5) remarkably changes by the deterioration state of the output mirror (2) (i.e., the more the mirror deteriorates, the higher the beam power becomes).