LASER MACHINING APPARATUS

摘要

The present invention is to provide a laser machining apparatus capable of performing machining a workpiece without degrading power density of each of the pulse laser beams even though a pulse laser beam is divided into two paths. A laser machining apparatus according to the present invention comprises: a workpiece holder unit to hold a workpiece; and a laser irradiation unit to irradiate the workpiece held by the workpiece holder unit with a laser beam. The laser beam irradiation unit includes: a pulse laser to emit a pulse laser beam at a predetermined repetition frequency; a first collimator and a second collimator to collimate the pulse laser beam emitted from the pulse laser; and a ramification unit arranged between the pulse laser and the first and second collimators to ramify the pulse laser beam emitted from the pulse laser toward the first collimator and the second collimator in turn, wherein the ramification unit has a photo-elastic modulator consisting of a piezoelectric device and a synthetic quartz to modulate a polarization surface of the laser beam into 0 and 90 degrees in turn by applying a high-frequency voltage with a frequency corresponding to a resonance frequency of the synthetic quartz to a piezoelectric device.