Patent attributes
A laser processing machine includes a beam parameter product variable device, and a beam diameter variable device. The beam parameter product variable device sets beam parameter products of a laser beam to a predetermined value. The beam diameter variable device includes a first lens that is movable in an optical axis direction and having a positive focal length, and converts divergent light of a laser beam emitted from an emission end of the laser beam into convergent light, and a second lens that is movable in the optical axis direction and having a negative focal length on which the convergent light is incident. A third lens having a positive focal length, focuses the laser beam emitted from the beam diameter variable device, and irradiates a plate material with the focused laser beam.