OPTICAL SYSTEM AND LASER PROCESSING APPARATUS

摘要

Provided are an optical system and a laser processing apparatus with which the energy intensity distribution of laser light at a processing point can be made higher in a peripheral region than in a center region in a simple manner. An optical system is provided with a collimating lens group that emits laser light including parallel rays; an axicon lens that has a circular conical shape and into which the light emitted from the collimating lens group enters; and a focusing lens group that focuses the light emitted from the axicon lens, wherein a conical surface of the axicon lens is positioned on the collimating lens group side, and a flat surface of the axicon lens is positioned on the focusing lens group side.