We have developed a computing method to determine the geometrical parameters of fibers and the textile periodical structure. This method combines two two-dimensional discrete fast Fourier transforms to calculate a diffraction pattern from a diffraction pattern image of material under consideration. The result is the same as that of observation of a diffraction pattern which is achieved by illuminating the diffraction pattern image of material by a beam of coherent monochromatic light. After the first transform we obtain the Fraunhofer diffraction picture with clearly visible elements of the periodical structure of material, but distances in this picture are reciprocally proportional to distances in the periodical structure of the source object so additional calculations are required. After the second transform we have a clear periodical structure of diffraction maximums where distances between them are equal to distances between repeating elements in the source material (fibers, knots, yarns, etc.).
References
[1]
Calvimontes, A.; Badrul Hasan, M.M.; Dutschk, V. Effects of Topographic Structure on Wettability of Woven Fabrics. In Woven Fabric Engineering; Dubrovski, P.D., Ed.; Sciyo: Rijeka, Croatia, 2010; pp. 71–92.
[2]
Lord, P.R. Handbook of yarn technology: science, technology and economics; CRC Press: Boca Raton, Florida, USA, 2003.
[3]
Shlyakhtenko, P.G. Features of the diffraction monitoring of the geometrical parameters of knitted hosiery fabric. J. Opt. Technol. 2004, 71, 795–798, doi:10.1364/JOT.71.000795.
[4]
Shlyahtenko, P.G.; Pimenov, V.I.; Kofnov, O.V. Use of two-dimensional discrete Fourier transformation for the computer analysis of a material with repeating structure. Autom. Modern Technol. 2013, 7, 20–27.
[5]
Born, M.; Wolf, E. Principles of Optics: Electromagnetic Theory of Propagation, Interference and Diffraction Light, 7th ed. ed.; University Press: Cambridge, UK, 1997.
[6]
Shlyakhtenko, P.G.; Shkuropat, S.N.; Nefedov, V.P. Computer analysis of models of optical images of plain weaves. J. Opt. Technol. 2007, 74, 476–478, doi:10.1364/JOT.74.000476.
[7]
Goodman, J.W. Introduction to Fourier Optics, 3rd ed ed.; Robert & Company Publishers: Greenwood Village, Colorado, USA, 2005.
[8]
Pan, R.; Gao, W.; Liu, J.; Wang, H. Automatic Inspection of Woven Fabric Density of Solid Colour Fabric Density by the Hough Transform. Fibres Text. East. Eur. 2010, 18, 46–51.
