A method and system for laser pre-cutting a layered material (31) with a laser beam (14) is disclosed. The layered material (31) comprises at least one tensile stress layer (TSL), at least one compression stress layer (CSL1, CSL2), and at least one interface region (IR1, IR2) between the at least one tensile stress layer (TSL) and the at least one compression stress layer (CSL1, CSL2) and is transparent to allow propagation of the laser beam (14) through the layered material (31). The method may comprise setting an optical beam path (8) and a laser characteristic of the laser beam (14) such that an interaction of the laser beam (14) with the layered material (31) generates an elongate damage region (57) in the layered material (31), and, for each of a series of pre-cut positions (X.sub.N−1, X.sub.N, X.sub.N+1) of the layered material (31), pre-cutting the layered material (31) by positioning the layered material (31) and the laser beam (14) with respect to each other and irradiating the laser beam (14) such that the respective elongate damage regions (57) extend across the at least one interface region (IR1, IR2).

The present invention relates to a laser cutting technology for cutting and separating thin substrates of transparent materials, for example to cutting of display glass compositions mainly used for production of Thin Film Transistors (TFT) devices. The described laser process can be used to make straight cuts, for example at a speed of >1 m/sec, to cut sharp radii outer corners (<1 mm), and to create arbitrary curved shapes including forming interior holes and slots. A method of laser processing an alkaline earth boro-aluminosilicate glass composite workpiece includes focusing a pulsed laser beam into a focal line. The focal line is directed into the glass composite workpiece, generating induced absorption within the material. The workpiece and the laser beam are translated relative to each other to form a plurality of defect lines along a contour, with adjacent defect lines have a spacing of 0.1-20 microns.

Methods and apparatus for separating substrates are disclosed, as are articles formed from the separated substrates. A method of separating a substrate having first and second surfaces includes directing a beam of laser light to pass through the first surface and, thereafter, to pass through the second surface. The beam of laser light has a beam waist located at a surface of the substrate or outside the substrate. Relative motion between the beam of laser light and the substrate is caused to scan a spot on a surface of the substrate to be scanned along a guide path. Portions of the substrate illuminated within the spot absorb light within the beam of laser light so that the substrate can be separated along the guide path.

Methods of producing a glass sheet each comprise the step of creating a vacuum to force the entire lateral portion of the glass ribbon to engage an anvil portion of a breaking device in the elastic zone. The vacuum is provided by a plurality of pressure zones that are operated independent from one another, wherein each pressure zone is provided with a set of suction cups. In further examples, glass ribbon breaking devices each include a plurality of pressure zones that are configured to be operated independent from one another with each pressure zone being provided with set of suction cups.

A method of separating a substrate includes directing a laser beam into the substrate such that a focal line is formed with at least a portion of the laser beam focal line within a bulk of the substrate at an oblique angle with respect to a laser-incident surface of the substrate. The laser beam focal line is formed by a pulsed laser beam that is disposed along a beam propagation direction. The method further includes pulsing the pulsed laser beam from a first edge of the substrate to a second edge of the substrate in a single pass. The laser beam focal line generates an induced multi-photon absorption within the substrate that produces a damage track within the bulk of the substrate along the laser beam focal line, and the damage track is at an oblique angle relative to the laser-incident surface of the substrate.

A strengthened glass sheet is separated into undamaged sheet segments by mechanically scribing one or more vent lines of controlled depth into the sheet surface, the depths of the scribed lines being insufficient to effect sheet separation, and then applying a uniform bending moment across the vent lines to effect separation into multiple sheet segments, the vent lines being scribed from crack initiation sites comprising surface indentations formed proximate to the edges of the glass sheet.

A strengthened glass sheet is separated into undamaged sheet segments by mechanically scribing one or more vent lines of controlled depth into the sheet surface, the depths of the scribed lines being insufficient to effect sheet separation, and then applying a uniform bending moment across the vent lines to effect separation into multiple sheet segments, the vent lines being scribed from crack initiation sites comprising surface indentations formed proximate to the edges of the glass sheet.

Methods and apparatus for separating substrates are disclosed, as are articles formed from the separated substrates. A method of separating a substrate having first and second surfaces includes directing a beam of laser light to pass through the first surface and, thereafter, to pass through the second surface. The beam of laser light has a beam waist located at a surface of the substrate or outside the substrate. Relative motion between the beam of laser light and the substrate is caused to scan a spot on a surface of the substrate to be scanned along a guide path. Portions of the substrate illuminated within the spot absorb light within the beam of laser light so that the substrate can be separated along the guide path.

Embodiments of the present method of laser cutting a laser wavelength transparent glass article comprises feeding at least one glass article to a pulsed laser assembly having at least one pulsed laser, wherein the pulsed laser defines a laser beam focal line with a length of 0.1-100 mm, the glass article being comprised of two end sections, and at least one lateral surface disposed lengthwise between the end sections. The method further comprises laser cutting at least one perforation line onto the lateral surface of the glass article while there is relative motion between the glass article and the pulsed laser and separating the glass article along the at least one perforation line to yield a laser cut glass article.

A method of manufacturing a partially textured glass article that includes (a) providing partially textured mother glass substrate that includes a first main surface and a second main surface which are opposed to each other; (b) irradiating the first main surface of the glass substrate with a laser to form a separating line on the first main surface that defines contour lines and extends from the first main surface to the second main surface dividing the glass article from the glass substrate, the glass article being a size smaller than the mother glass substrate; and (c) separating the partially textured glass article is separated from the mother glass substrate by the separating line. The method allows cutting a large partially textured mother glass substrate, with high precision, into smaller articles of partially textured glass at a requested size.