Abstract: According to one embodiment, a laser processing device includes a light irradiation section, and an optical element. The optical element includes a first transparent member provided via a gap with a tip of the light irradiation section, and a second transparent member. The first transparent member includes a first surface opposed to the tip of the light irradiation section, and a second surface provided so as to be connected to the first surface. The second transparent member includes a flat surface and a convex surface, the flat surface being provided so as to be opposed to the second surface of the first transparent member, the light passed through the first transparent member passing through the convex surface. An optical axis of the laser beam passing through the first surface and an optical axis passing through the convex surface are different from each other.

Abstract: In one embodiment, a laser peening apparatus includes an output unit (41) configured to output laser light (6); a light-guide unit (31) configured to guide the outputted laser light (6); a condenser lens (42) configured to condense the guided laser light (6); an irradiation nozzle (32) configured to radiate the condensed laser light (6); a focus-change unit (50) configured to change a focal position of the laser light (6) based on distance from an irradiation target (4, 5) of the laser light (6) to the irradiation nozzle (32); and a control unit (66) configured to apply laser peening by radiating the laser light (6) toward the irradiation target (4, 5) which is in contact with water.

Abstract: According to an embodiment, a laser processing apparatus has: a laser light source; a light collector; a water nozzle; a sound sensor; a timer; and a distance calculator. The light collector collects the laser light on a workpiece. The water nozzle supplies a water stream to a surface to be treated of the workpiece. The sound sensor is provided at a predetermined position relative to at least one of the water nozzle and the light collector, and receives a sound coming from the surface to be treated. The timer detects a detected time width from a reference time point to a time point when the sound sensor receives the sound. The distance calculator calculates a distance from one of the water nozzle and the light collector to the surface to be processed.

Abstract: One embodiment of the laser processing apparatus is for surface treatment by supplying liquid to a surface of the target member and irradiating pulsed laser light to the surface of the target member via the liquid. The apparatus includes a laser oscillator and a liquid supply. The laser oscillator irradiates the laser light to the surface through the liquid via an optical window. The liquid supply is configured to supply the liquid to the surface of the target member via a flow path passing on an outer surface of the optical window. When the liquid is in contact with a laser light emission surface of the optical window, the laser light emission surface transmits the laser light. When the liquid is not in contact with the laser light emission surface, the laser light emission surface reflects the laser light.