Temporal phase unwrapping for fringe projection profilometry aided by recursion of Chebyshev polynomials

This paper presents a temporal phase-unwrapping method for fringe projection profilometry. With it, a sequence of phase-shifting fringe patterns is projected onto the measured object for getting the wrapped phase map and achieving a high measurement resolution, and an additional sequence corresponding to Chebyshev polynomials is used for determining their fringe orders. For effectuating this method, we deduce an algorithm by use of the recursive property of Chebyshev polynomials. This algorithm, combined with a correction operation in the least-squares sense, allows us to accurately estimate the fringe orders in the presence of noise. Experimental results demonstrate the proposed method to be effective in restoring the absolute phase maps of fringe patterns.