Abstract: Methods and apparatus are provided for forming an initiation flaw (111) in the surface (114) of a glass sheet or glass ribbon (13). The initiation flaw (111) is used in connection with a laser light beam (121) and a cooling area produced by a cooling nozzle (119) to from a score line (115) in the surface (114) of the sheet or ribbon (13). The initiation flaw (111) is formed by a mechanical scoring head (20) which is carried by moving carriage (14) and which undergoes retrograde motion (19) relative to the carriage (14) so as to increase the time available for forming the initiation flaw (111).

Abstract: A method of cutting glass that prevents uncontrolled crack propagation when high background stress is present, either in the form of thermal residual stress, external mechanical stress or a combination thereof. The method includes masking an edge of the glass by blocking the beam using highly reflective or absorptive material located near the glass surface, or deposited on the surface in a form of a thin film (or highly reflective paint) to prevent uncontrolled crack initiation and propagation starting from the glass edge. The initiation of the laser scoring is located at a predetermined distance from the glass edge. Yet another aspect of the invention embodies stopping propagation of the vent at the exiting end of the score line.

Abstract: A method is provided for separating or dividing strengthened glass articles, particularly strengthened glass sheets, into at least two pieces, one of which has a predetermined shape and/or dimension. A flaw is initiated in the glass at a depth that is greater than the depth of the strengthened surface layer of the glass, and a vent extending from the flaw is created at a vent depth that is greater than the depth of and outside the strengthened surface layer to at least partially separate the glass. In one embodiment, the vent is generated by treating the glass with a laser to heat the glass to a temperature in a range from about 50° C. below the strain point of the glass up to a temperature between the strain point and the anneal point of the glass. A glass article having at least one strengthened surface and at least one edge having an average edge strength of at least 200 MPa is also described.

Abstract: Methods of using a laser to separate a glass sheet is presented that employs an elongated and, preferably, asymmetrically-truncated laser beam. The methods allow glass sheets suitable for use in modern display applications to be separated at speeds up to about 200 mm/s with low levels of residual stress, e.g., levels of residual stress which are less than or equal to 100 psi, and preferably less than 50 psi. Glasses with high coefficients of thermal expansion (e.g. greater than about 35×10?7/° C.) maybe separated at faster speeds. Such low levels of residual stress translate into low levels of distortion during the manufacture of display panels (e.g., LCD panels) as well as in improved properties (geometry, strength, defect-free etc.) of the separated edges. The methods can be used with glasses of various types including glasses having high coefficients of thermal expansion and also with glass sheets of different thickness.

Abstract: Disclosed are systems and methods for separating a sheet of glass by directing a microwave beam and a laser beam at a sheet of glass to propagate a crack across the sheet. A laser beam spot formed on the glass sheet by the laser at least partially overlaps a microwave beam spot produced on the sheet by the microwave beam and can be used to generate an increased power density in the overlap region, thereby forming a preferential direction for crack propagation.

Abstract: Disclosed are systems for scoring non-flat materials including non-flat glass sheets (1000). In one embodiment, a laser scoring system is described. The laser scoring system includes a laser (102) and an optical head (106). The optical head (106) is configured to receive output from the laser (102) and focus the output into an elongated laser beam having a beam waist and an extended focal depth of greater than ±5 mm relative to the center of the beam waist with a power density sufficient for scoring a material having at least a portion within the extended focal depth. In one aspect the system can include a beam expander (104). The beam expander (104) receives the output from the laser (102), expands the output from the laser to an expanded laser beam, and transmits the expanded laser beam to the optical head (106).

Abstract: Disclosed are systems and methods for separating a glass sheet along a predetermined line. Laser beams are generated and shaped into elongated laser beams. Arm members are provided that are pivotally coupled together to form a chain of arm members. Each elongated laser beam is directed therefrom a respective laser beam toward the glass sheet to form a contiguous chain of elongated laser beams thereon a surface of the glass sheet. The arm members can be moved to move the contiguous chain of elongated laser beams along the predetermined line to scoring the glass sheet along the predetermined line.

Abstract: Disclosed are systems and methods for scoring and separating a glass sheet along a curved trajectory using a laser and optics. The system includes a laser that generates a laser beam, a focusing lens, and a conical optical component such as a conical lens or a reflective conical milTor. The laser directs the laser beam through the focusing lens and conical lens to create a curved score line that is projected onto a glass sheet to create a curved score line, along which the glass sheet can be separated. Optionally, the laser directs the laser beam through the focusing lens towards a conical mirror, off of which the laser beam is reflected toward the glass sheet to create a curved score line.

Abstract: An apparatus for drying a surface of a substrate during laser scoring. During the laser scoring process, a narrow cooling liquid jet follows the laser beam to create and propagate a partial vent. Precision of the scoring and overall stability of the process depend upon the accuracy of the alignment of the beam and the fluid stream. In one aspect, the apparatus has a conduit with at least one interior chamber in communication with at least one nozzle orifice. The conduit is configured to be in communication with a pressurized gas source to introduce the pressurized gas into the chamber. The pressurized gas forms a curtain of gas that is used to clean the cooling fluid therefrom the surface of the substrate.

Abstract: Disclosed are systems and methods for scoring glass sheets. A laser beam can be generated having a substantially uniform peak energy density along at least a portion of its length. The laser beam is moved across the glass sheet to create a score line. Further, the glass sheet can be separated along the score line. In some aspects, the laser beam is bimodal and comprises approximately 60-70% TEM00 mode and approximately 30-40% TEM01* mode.

Abstract: A method and an apparatus for both scoring and separating a brittle material, and in particular a glass sheet or substrate, using only a single laser beam. A radiation zone created by the beam incident on the glass substrate, and the radiation zone is effectively formed into two portions by a coolant jet incident on the radiation zone. The radiation zone is separated into a leading portion, which generates a vent crack partially through a thickness of the substrate, and a trailing portion that propagates the vent crack through the remainder of the substrate, thereby separating the substrate.