Laser processing machine and laser processing method
A laser processing machine includes a collimating lens configured to convert a laser beam into a collimated beam, a condensing lens configured to focus the collimated beam onto a sheet metal, a first lens arrays structured by arranging a plurality of first microlenses in a planar shape so as to refract the laser beam by each of the first microlenses, a second lens array structured by arranging a plurality of second microlenses in a planar shape so that a center thereof is set at a same position in an optical axis direction as a center of the first lens array so as to make the laser beam emitted from each of the first microlenses incident and refracted by a corresponding one of the second microlenses, and a rotation mechanism configured to rotate at least one of the first lens array and the second lens array along an outer periphery thereof.
1 . A laser processing machine, comprising:
a collimating lens configured to convert an incident laser beam into a collimated beam;
a condensing lens configured to focus the converted collimated beam so as to irradiate a sheet metal;
a first lens array structured by arranging a plurality of first microlenses in a planar shape so as to refract the incident laser beam by each of the first microlenses;
a second lens array structured by arranging a plurality of second microlenses in a planar shape to be in a same shape as the first lens array so that a center of the second lens array is set at a same position in an optical axis direction as a center of the first lens array so as to make the laser beam emitted from each of the microlenses of the first lens array incident and refracted by a corresponding one of the second microlenses; and
a rotation mechanism configured to rotate at least one of the first lens array and the second lens array along an outer periphery of the at least one of the first lens array and the second lens array.
2 . The laser processing machine according to claim 1 , wherein each microlens of the first lens array and each microlens of the second lens array are formed in a regular hexagon or a square.
3 . The laser processing machine according to claim 1 , wherein a focal length of each microlens of the second lens array is set shorter than a focal length of each microlens of the first lens array.
4 . The laser processing machine according to claim 1 , wherein the first lens array and the second lens array are arranged between the collimating lens and the condensing lens.
5 . A laser processing method performed by the laser processing machine according to claim 1 , the laser processing method comprising rotating at least one of the first lens array and the second lens array along the outer periphery of the at least one of the first lens array and the second lens array by a predetermined angle with the rotation mechanism such that a condensing diameter of a laser beam condensed by the condensing lens becomes a predetermined size.