A spatial algorithm to reduce phase wraps from two dimensional signals in fringe projection profilometry

Abstract

A spatial algorithm to reduce phase wraps from two dimensional signals in fringe projection profilometry http://researchonline.ljmu.ac.uk/3438/ Article LJMU has developed LJMU Research Online for users to access the research output of the University more effectively. Copyright © and Moral Rights for the papers on this site are retained by the individual authors and/or other copyright owners. Users may download and/or print one copy of any article(s) in LJMU Research Online to facilitate their private study or for non-commercial research. You may not engage in further distribution of the material or use it for any profit-making activities or any commercial gain.The version presented here may differ from the published version or from the version of the record. Please see the repository URL above for details on accessing the published version and note that access may require a subscription. AbstractIn this paper, we present a novel algorithm to reduce the number of phase wraps in two dimensional signals in fringe projection profilometry. The technique operates in the spatial domain, and achieves a significant computational saving with regard to existing methods based on frequency shifting.The method works by estimating the modes of the first differences distribution in each axial direction. These are used to generate a tilted plane, which is subtracted from the entire phase map. Finally, the result is re-wrapped to obtain a phase map with fewer wraps. The method may be able to completely eliminate the phase wraps in many cases, or can achieve a significant phase wrap reduction that helps the subsequent unwrapping of the signal.The algorithm has been exhaustively tested across a large number of real and simulated signals, showing similar results compared to approaches operating Optics and Lasers in Engineering February 9, 2016 in the frequency domain, but at significantly lower running times.

Comparación de métodos perfilométricos por Transformada de Fourier 1D y 2D

“…La FTP fue propuesta en los años 80's en [4][5] donde se muestra que es posible identificar la diferencia que se producía entre una cresta y un valle, con lo cual se podían analizar diferentes alturas que representarían al objeto. A partir de estas publicación muchos investigadores han abordado el tema realizando variaciones al método original como se mencionan en [6 -8]; proponiendo filtros como [9][10][11]; utilizando algoritmos de desdoblamiento de fase robustos donde se eleva la calidad de la reconstrucción al mismo tiempo que el costo computacional también se ve incrementado, como ejemplo del uso de estos algoritmos podemos encontrar los presentados en [12][13][14][15][16][17], o cambiando el uso de la Transformada de Fourier por otras Transformadas como en [18].…”

Precise and fast phase wraps reduction in fringe projection profilometry

“…Attempts have also been made at reducing the number of phase wraps in the phase map by estimating and eliminating the carrier, to reduce the complexity of phase unwrapping. Miguel et al [15] proposed a algorithm to reduce the phase wraps by generating and subtracting the tilted plane from the entire phase map after estimating the modes of the first differences distribution in each axial direction. Feng et al [16] proposed a carrier removal method based on principal component analysis, in which the phase of the carrier can be extracted from the first dominant component acquired.…”

Comparación de filtros para el análisis del espectro espacial bidimensional de Fourier, en el proceso de digitalización 3D

“…En años recientes investigadores como Feng S, Feng L, Miguel A. Hai L, han realizado propuestas para mejorar los algoritmos de digitalización 3D por Perfilometria de Fourier, tanto del proceso general de digitalización 3D, como en [7,8,9,10], así también proponen mejoras en el proceso de desdoblamiento de fase tal como se establece en [11,12,13,14].…”