LASER IRRADIATION DEVICE, FLUID SUPPLY DEVICE, AND LASER PROCESSING METHOD

To provide a laser irradiation device which improves processing quality by atmosphere control at an irradiation location, and so on.SOLUTION: A laser irradiation device comprises: an optical system including a condensing optical system 10 for condensing a laser beam R generated by a laser oscillator at a prescribed focus position BS, and a deflection optical system 20 for deflecting the laser beam to scan a focus position along a surface of an irradiation object O in a prescribed scanning pattern; and fluid supply parts 90, 100 which supply fluids PG, SG each containing an inert gas as a main component, to an area including the scanning pattern at the focus position, thereby making at least the focus position have an atmosphere filled with the fluids.SELECTED DRAWING: Figure 1 【課題】照射箇所の雰囲気制御により加工品質を向上したレーザ照射装置等を提供する。【解決手段】レーザ照射装置を、レーザ発振器が発生するレーザ光Ｒを所定の焦点位置ＢＳにおいて集光させる集光光学系１０と、レーザ光を偏向させて焦点位置を照射対象物Ｏの表面に沿って所定の走査パターンで走査させる偏向光学系２０とを含む光学系と、焦点位置の走査パターンを含む領域に不活性ガスを主成分とする流体ＰＧ，ＳＧを供給して少なくとも焦点位置を流体が充満した雰囲気とする流体供給部９０，１００とを備える構成とする。【選択図】図１