Patent ID: 7471383

Claim:
A method of quantitatively analyzing optical distortion in shaped glass comprising: providing a rigid horizontal surface on which to position a shaped sheet of glass; positioning a flat rigid surface in an essentially vertical orientation and in a predetermined proximity to the horizontal surface on which the shaped glass is to be positioned, the vertical flat surface having a repetitive pattern disposed thereon; providing at least one source of visible light to illuminate the vertical, rigid patterned surface; providing an optoelectronic device capable of receiving and recording a digital image, which optoelectronic device is positioned in a predetermined proximity to the rigid horizontal surface and to the flat, patterned vertical surface; providing a computer programmed with at least one algorithm capable of receiving a digitized image from the optoelectronic device; precisely orienting a shaped sheet of glass having at least one major convex surface on the rigid horizontal surface relative to the vertical, rigid flat surface; selecting an area of the at least one major convex surface for analysis; utilizing the optoelectronic device to capture a digital image of the pattern formed on the shaped sheet of glass by the light reflected to the optoelectronic device from the patterned vertical rigid surface; and electronically transferring the digital image of the pattern on the surface of the shaped glass sheet to the computer, wherein the at least one algorithm computes the maximum percent change in apparent variation in a contiguous group of a predetermined number of the shapes of the repetitive pattern disposed on the vertical flat surface in the area selected for analysis.