Machine vision based interferometry for measurement of flatness error in micro and nano manufacturing

Abstract

Abstract Interferometer and machine vision both are very trending technologies in the manufacturing industry for quality inspection purpose. Interferometers are commonly used to measure surface contour, flatness, surface finish. Machine vision also plays a vital role in the evaluation of the surface quality and surface profile of components under inspection. In this paper, a combination of interferometer and machine vision principles is used to count the number of fringes to determine taper angle and parallelism error in micro and nanometer range. An interferogram is captured by a camera and image acquisition algorithm. Image processing algorithms are used to count the number of fringes and calculating taper angle as well as flatness (parallelism) error for slip gauge surface.