Gap measuring apparatus and method

摘要

An apparatus and method to measure a gap width distance, specifically the distance between the lip of a coating hopper and the tangential edge of a coating roller or the support on the roller, is disclosed herein. The apparatus includes a long range microscope coupled with a CCD camera to provide a computer with an image. From this image the computer calculates first and second derivatives of the light intensity values between each pixel and determines the pixel locations of the two edges.