Patent ID: 8875967

Claim:
A method for scribing a chemically strengthened glass sheet comprising the steps of: forming a crack initiation site in a first surface and proximate to a first edge of a chemically strengthened glass sheet with a scoring implement traversing along the first surface at a first speed, the chemically strengthened glass sheet comprising a surface compression layer of layer depth DOL and the crack initiation site comprising a surface indentation extending into the first surface, wherein the formation of the crack initiation site is formed by edge-crushing the first edge of the chemically strengthened glass sheet by contacting the first edge of the chemically strengthened glass sheet with the scoring implement that is offset to a position below the level of the first surface of the chemically strengthened glass sheet; and mechanically scoring the first surface with the scoring implement traversing along the first surface from the crack initiation site toward a second edge of the chemically strengthened glass sheet at a second speed greater than the first speed to scribe a vent line that extends along the first surface and into the chemically strengthened glass sheet to a vent depth at least equal to DOL but less than a fracture depth without causing self-separation of the chemically strengthened glass sheet, wherein a vent line extending to the fracture depth would cause self-separation of the chemically strengthened glass sheet.