Patent ID: 8913254

Claim:
A method for measuring the wall thickness profile along a line on the surface of a transparent object comprising placing a first light source oriented towards the object, placing a second light source oriented towards the object, placing an imaging device symmetrically between the first and second light source and oriented to acquire an image comprising first and second reflections of the first and second light source respectively, moving the light sources and imaging device relative to the object such that the light sources and imaging device follow the same trajectory, acquiring and saving images during the movement, and determining the wall thickness profile by correlating first and second images, wherein the first image refers to an image taken before or during movement and the second image refers to an image taken at a subsequent time during movement when the imaging device is in the position of the first light at the time the first image was taken and the second light is in the position of the imaging device at the time the first image was taken.