System and method for tracking optical fringes, to measure the offset between two surfaces using an interferometer

摘要

The band matching method for enabling accurate determination of a disparity between two surfaces using an interferometer, comprises capturing an image of two surfaces with a pattern of interferometric fringes superimposed over the image and over the surfaces. A discontinuity in a primary fringe is identified that is used for the determination of the disparity, and a pixel value is moved from an adjacent fringe to the primary fringe to fill in the discontinuity. Two equations are arithmetically fitted to portions of the primary fringe over the first and second surfaces respectively; The disparity between the surfaces is determined based upon the first and second equations.