Patent ID: 6806459
Filing Date: 2004-10-19
Classification: G01B

Abstract:
A method of measuring wall thickness of a transparent cylindrical container that comprises the steps of:(a) moving the container transversely of its axis along a defined path while simultaneously rotating the container about its axis, (b) directing onto a wall of the container, as it rotates and translates in said steps (a), a line-shaped light beam having a long dimension perpendicular to the axis of the container and parallel to the direction of translation of the container, (c) directing onto a light sensor light energy reflected from portions of outer and inner wall surfaces of the container that are perpendicular to light energy directed onto the container in said step (b), as viewed from a direction parallel to the container axis, and (d) measuring container wall thickness as a function of separation at said sensor between said light reflected from said outer and inner wall surfaces.