Method and device for cutting flat work pieces of a brittle material

US6635848B2 · kind B2 · utility

Assignee

• Schott Glas · DE

Inventors

• Dirk Hauer · Nordenham, DE
• Berndt Hoetzel · Wörrstadt, DE

Key dates

• Filing date: May 20, 2002
• Grant date: Oct 21, 2003
• Expiry date: May 20, 2022

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T225/304
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

The method of making a freeform cut on a work piece made of brittle material, such as glass, includes producing a linear focal point from a laser beam and a cold spot following the linear focal point on the work piece so that at least 60 percent of a laser beam energy output is concentrated at opposite ends of the linear focal point; moving the linear focal point along a specified contour for forming the cut and adjusting a length of the focal point according to a contour line curvature, so that the opposite ends lie on the contour, even when the contour is curved, in order to make the freeform cut. The device for performing this method includes a numerical trajectory control device (4) for positioning the linear focal point as it moves along the contour and a profile control device (3) cooperating with the numerical trajectory control device (4) for controlling a length (S) of the linear focal point (1).