To provide a laser irradiation unit and a laser processing apparatus in which utilization efficiency of a laser beam is improved and a uniformity degree of processing can be maintained even if a processing wavelength is changed.
A laser processing system 100 comprises: a reflecting mirror 33 which deflects a laser beam from a laser source 50 by a deflecting plane 33a supported as movable; a mirror-moving structure 34 which arranges the deflecting plane 33a as inclinable against an optical axis P1 of the laser beam and as movable in a direction to the optical axis P1; a spatial modulation element 6 for forming ON light 62 going to a surface to be irradiated 11a of a substrate 11 which is irradiated with the laser beam; a spatial-modulation-element-inclining structure 36 which makes the spatial modulation element 6 inclinable; a lens-moving structure 38 which varies a focus position of a projection optical system 4 emitting the laser beam to the spatial modulation element 6; and, a projection optical system 8 for projecting the ON light 62 formed by the spatial modulation element 6 onto the surface to be irradiated 11a.
Yasushi Hasegawa
Osamu Shinoura