DEVICE AND METHOD FOR LASER BEAM MACHINING

摘要

PROBLEM TO BE SOLVED: To conduct high-grade machining by converting the strength distribution of a laser beam on a workpiece to a uniform distribution in a device and a method for projecting the image of a mask on the workpiece for the purpose of conducting laser beam machining. SOLUTION: In this device, the laser beam 12 is oscillated from a CO2 laser oscillator 11, the strength distribution of the laser beam 12 on the mask 16 is made uniform by means of a uniformizing optical system 13 and a projection optical system 14, and the image of the mask 16 is projected on the workpiece 19 by means of a projection lens 18 so as to machine the workpiece 19 while uniformizing the strength distribution. A lens 15 is disposed just in front of the mask 16 in order to minimize a deterioration in the uniformity of the strength of the laser beam 12 on the object 19, and the radius of curvature of the wave front of the laser beam 12 on the mask 16 is optimized so as to minimize the deterioration in the uniformity of the strength of the laser beam 12 on the object 19 and enable the high-grade machining.