Patent ID: 11906483
Assignee: CORNING INCORPORATED
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 8:
9. A method of testing edge strength of a sheet of material along an edge of the sheet, the method comprising:
applying a surface pattern of visual markers on a surface of the sheet in a region of interest along the edge of the sheet;
obtaining a first optical image of the surface of the sheet in the region of interest without any 3-point bending load applied to the region of interest;
applying a 3-point bending load to the region of interest along the edge of the sheet;
obtaining a second optical image of the surface of the sheet in the region of interest while the 3-point bending load is being applied to the region of interest; and
determining stress on the surface of the region of interest along the edge of the sheet resulting from the application of the 3-point bending load based on the first optical image and the second optical image, wherein the surface pattern facilitates optically measuring the strain in the sheet of material.