US 6,642,480 B2 · Laser processing method and laser processing apparatus

Abstract

In a laser processing apparatus including an ultra-short pulse laser a focusing optical system and processing a work by projecting a beam delivered through the focusing optical system on to the work, the focusing optical system has at least a pair of diffractive surface and a refractive surface, and chromatic aberration is corrected or chromatic aberration and pulse extension are corrected by making use of the diffractive dispersions due to and the diffractive surface the refractive dispersion due to of the refractive surface. With this arrangement, chromatic aberration is corrected or both chromatic aberration and pulse expansion are corrected in the processing with the ultra-short pulse laser and thereby improve the practical use and value of the processing by improving its accuray, qualiy and speed.

Claims7

Dependent claims

A laser processing method comprising the steps of:

branching a pulse laser beam into a plurality of beams using a branching diffractive element;
correcting chromatic aberrations caused on the plurality of branched beams through a focusing optical system;
and
focusing and projecting the plurality of branched beams whose chromatic aberrations have been corrected, on a work,
wherein a focusing diffractive element having a focusing action is used as the focusing optical system, and the distance between the branching diffractive element and the focusing diffractive element is set approximately equal to the focusing length of the focusing diffractive element.

2 more elements

Dependencies are inferred from the claim text.

Laser processing method and laser processing apparatus

Life of this patent

Laser processing method and laser processing apparatus

Life of this patent

Abstract

Claims7