US Patent 7538048 Laser beam processing machine

A laser beam processing machine comprising a path distribution means for distributing a pulse laser beam oscillated by pulse laser beam oscillation means to a first path and a second path alternately, and one laser beam that passes through one of the paths and is converged by one condensing lens and the other laser beam that passes through the other path and is converged by the condensing lens are applied at different focusing points which have been displaced from each other in the direction of the optical axis, alternately with a time lag between them.