Patent ID: 6800831
Filing Date: 2004-10-05
Classification: B23K,C03B

Abstract:
A method for rapid cutting of a workpiece along a predetermined cutting line of any desired shape by means of laser beams, said workpiece being made of brittle material, said method comprising the steps of:a) generating the laser beams; b) focusing the laser beams onto the cutting line to form focused laser beams on the cutting line; c) guiding the focused laser beams one behind the other along the cutting line without melting the brittle material; d) shaping the respective laser beams so that respective beam cross-sections forming corresponding focal spots on a surface of the workpiece have predetermined shapes and intensity distributions; e) moving the workpiece and the laser beams relative to each other so that the focal spots move along the cutting line and the focused laser beams induce a thermo-mechanical stress in the brittle material without melting the brittle material; and f) guiding a cooling spot, which is produced by blowing a fluid cooling medium onto a heated cutting line section of the workpiece, along the cutting line following said focal spots so that said cooling spot increases said thermo-mechanical stress produced by the focused laser beams in the brittle material above a breaking strength of the brittle material.