Patent ID: 6501047
Filing Date: 2002-12-31
Classification: B23K,B28D,C03B,C03C,C04B

Abstract:
A method of laser-scribing to separate portions of a sheet of brittle material along a curvilinear path, the method comprising:rotating the sheet; impinging a first laser light beam at a first beam energy on a surface of the sheet to form a first laser spot having a first size to preheat the surface of the sheet to a first temperature; impinging a second laser light beam at a second beam energy on the surface of the sheet to form a second laser spot having a second size, spaced apart from and behind the first laser spot with respect to the rotating direction, to heat the surface to a second laser-scribing temperature higher than the first temperature; and directing a coolant to an area on the surface of the sheet behind the second spot with respect to the rotating direction.