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AssigneeCorning Incorporated
InventorsAnatoli A. Abramov, Yawei Sun, Wei Xu, Naiyue Zhou
Estimating the term…
Experimental data is presented which shows that laser scoring of glass sheets (112) with existing techniques produces unacceptable levels of residual stress in the separated sheets as the scoring speed is increased. Methods for solving this problem are disclosed which employ elongated and, preferably, asymmetrically-truncated laser beams (13). The methods allow glass sheets (112) to be scored at speeds of 1000 mm/s and above with low levels of residual stress, e.g., levels of residual stress which are less than or equal to 500 psi. 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 of the separated edges. The methods can be used with glasses of various types including glasses having low coefficients of thermal expansion.
A method of scoring a glass sheet comprising:
A method of operating a laser scoring system in which a vent is produced in a glass sheet by translating a truncated laser beam over a surface of the sheet at a speed S in tandem with a coolant area which has a center point, said method comprising selecting the amount of truncation of the laser beam, or the distance between the center point of the coolant area and the nearest end of the laser beam prior to truncation, or both the amount of truncation and the distance between the center point of the coolant area and the nearest end of the laser beam prior to truncation to control at least one of (i) the depth of the vent and (ii) the residual stress in sub-pieces produced from the sheet wherein the translation of the laser beam over the surface of the glass sheet at the speed S produces a maximum temperature at the surface of the glass sheet that is less than or equal to the glass' strain point.
A method of operating a laser scoring system in which a vent is produced in a glass sheet by translating a truncated laser beam over a surface of the sheet at a speed S in tandem with a coolant area which has an outer edge, said truncation of the laser beam producing a truncated edge proximal to the coolant area, said method comprising:
Dependencies are inferred from the claim text.