Laser processing device

Abstract

A laser processing device including: a laser oscillator; a processing table; a transmission optical system for transmitting laser light emitted from the laser oscillator to the processing table; a processing head for condensing and radiating the laser light transmitted via the transmission optical system to an object to be processed; a moving mechanism for changing a relative position between the object to be processed and the laser light to be radiated to the object to be processed; and a variable curvature spherical mirror. The transmission optical system includes a reflective beam expander mechanism for collimating and magnifying the laser light from the laser oscillator. The reflective beam expander mechanism includes a spherical mirror and a concave mirror having different curvatures in two orthogonal axes.

1 . A laser processing device, comprising:
 a laser oscillator for emitting laser light;   a processing table on which an object to be processed is placed;   a transmission optical system for transmitting the laser light emitted from the laser oscillator to the processing table;   a processing head for condensing and radiating the laser light transmitted via the transmission optical system to the object to be processed; and   moving means for changing a relative position between the object to be processed and the laser light to be radiated to the object to be processed,   wherein the transmission optical system comprises a reflective beam expander mechanism for collimating and magnifying the laser light from the laser oscillator, and   wherein the reflective beam expander mechanism comprises a mirror having different curvatures in two orthogonal axes.   
     
     
         2 . A laser processing device according to  claim 1 ,
 wherein the transmission optical system comprises an optical path length fixing mechanism placed at a position capable of receiving the laser light emitted from the mirror having different curvatures in two orthogonal axes,   wherein the optical path length fixing mechanism comprises a mirror group including a plurality of mirrors and a moving mechanism for translating the mirror group,   wherein the plurality of mirrors of the mirror group are placed so that a direction of travel of incident light to the mirror group and a direction of travel of output light from the mirror group are opposite and in parallel to each other, and   wherein the moving mechanism translates the mirror group with respect to the direction of the travel of the incident light and the direction of the travel of the output light so as to cancel out change in relative position between the object to be processed and the laser light to be radiated to the object to be processed to maintain a fixed optical path length of the laser light radiated to the object to be processed.