SYSTEM FOR MEASURING SURFACE FLATNESS USING SHADOW MOIRE TECHNOLOGY

A system for measuring surface characteristics of an electronic interconnection component, such as a printed circuit board, by analyzing shadow moir+E,acu e+EE patterns. Printed circuit boards are carried on a continuous conveyor under a grating. For each printed circuit board, a shadow moir+E,acu e+EE fringe pattern is created in response to a determination that the printed circuit board is properly located under a grating and within the field of view of a camera. Fringes of the shadow moir+E,acu e+EE fringe pattern are quantified over one or a multiple of analysis paths to determining if the printed circuit board is unacceptably warped, in which case a signal is generated. For each printed circuit board, multiple images can be captured and mathematically combined, by image subtraction, to produce an enhanced shadow moir+E,acu e+EE fringe pattern that is analyzed for warpage.