Underwater laser processing apparatus and underwater laser processing method

摘要

An underwater laser processing apparatus (100) includes an optical unit (3) and a nozzle (29). The optical unit irradiates a condensed laser beam generated by a YAG laser oscillator (35) to a certain point on a underwater workpiece (6). The nozzle has a gas exit for supplying a gas to the certain point. In the nozzle, an area surrounding the gas exit (25) extends to the surface of the workpiece. This area keeps the supplied gas between the nozzle and the workpiece to improve the underwater laser process.