SYSTEMS AND METHODS FOR ALTERING STRESS PROFILES OF GLASS

摘要

Methods for processing glass using select wavelength radiation in a convective environment, broadly referred to as “Local Temporary Annealing”, “LASER Edge Strengthening” and “LASER Enhanced Thermal Strengthening.” Local Temporary Annealing allows strengthened glass to be brought to a neutral stress state so daughter units can be cut from strengthened glass and other processes usually only performed on annealed glass. LASER Edge Strengthening allows surface compression to be thermally imparted to the edges of a whole sheet or daughter units cut from annealed glass, or modification of residual edge stress profiles in strengthened glass to produce stable, strengthened edges. LASER Enhanced Thermal Strengthening allows surface compression to be imparted to a sheet of annealed glass whilst maintaining reduced surface temperatures so the glass has superior geometric stability and surface compression can be imparted at levels not conventionally possible.

主权项

1. A method of cutting a parent unit of glass into daughter units, wherein the parent unit has a core between opposing first and second surfaces that define a thickness of the glass, comprising:
Cutting the parent unit of glass along a cut line to divide the parent unit into a plurality of daughter units, wherein at least one daughter unit has a cut edge when the parent unit is cut; and Strengthening an edge of at least one of the daughter units by locally heating the edge and core in proximity to the edge to a temperature above the glass transition temperature of the glass by applying second selected wavelength and intensity of radiation in combination with cooling to maintain the first and second surfaces below the glass transition temperature while heating the edge and core, and to cool the edge prior to the core on completion of the heating.