Abstract
This paper presents a method for measuring displacements and strain in digital speckle photography that is an alternative to currently used correlation techniques. The method is analogous to heterodyne speckle photogrammetry wherein optical Fourier transforms are taken of individually recorded specklegrams and combined in a heterodyne interferometer where an electronic phase meter measured the phase differences between the two transforms. Here, digital photographs are recorded and Fourier transformed so that their phase functions can be subtracted and fitted to a linear function of the transform coordinates. The effect of different recording and processing parameters is investigated. It is found that incoherent speckles give better results that those formed by coherent laser light. In addition, image correlation is used to process an identical data set so that comparison of the two methods can be made.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsPreview
Unable to display preview. Download preview PDF.
References
A. E. Ennos, “Speckle Interferometry,” in Progress in Optics Vol. XVI, Emil Wolf, Ed. (North-Holland, Amsterdam, 1978), Chap. 4, pp. 235–290.
K. A. Stetson and G. B. Smith, “Heterodyne readout of specklegram halo fringes,” Appl. Opt., 19, 3031–3033 (1980).
K. A. Stetson, "Speckle and Its Application to Strain Sensing," Proc. SPIE 353, 12–18 (1983).
K. A. Stetson, "The Use of Heterodyne Speckle Photogrammetry to Measure High Temperature Strain Distributions," Proc. SPIE, 370, 46–55 (1983).
K. A. Stetson, "The Effect of Scintillation Noise in Heterodyne Photogrammetry," Appl. Opt. 23, 920–923 (1984).
K. A. Stetson, "Strain Measurement Using Heterodyne Photogrammetry of White-Light Specklegrams," Exp. Mech., 25, 312–315 (1985).
K. A. Stetson, J. Wahid, and P. Gauthier "Noise-immune phase unwrapping by use of calculated wrap regions, Appl. Opt. 36, 4830–4838 (1997).
Mikael Sjödahl, “Digital Speckle Photography” in Digital Speckle Pattern Interferometry and Related Techniques, P. K. Rastoji, (Ed.), J. Wiley & Sons, New York, 2001, Chap. 5.
J. M. Huntley, “Automated Analysis of Speckle Interferograms” in Digital Speckle Pattern Interferometry and Related Techniques, P. K. Rastoji, (Ed.), J. Wiley & Sons, New York, 2001, Chap. 2, pp. 89–95.
M. Sjödahl and L. R. Benckert, “Electronic speckle photography: analysis of an algorithm giving the displacement with subpixel accuracy,” Appl. Opt. 32, 2278–2284 (1993).
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2011 Springer Science+Businees Media, LLC
About this paper
Cite this paper
Stetson, K.A. (2011). Analysis of speckle photographs by subtracting phase functions of digital Fourier transforms. In: Proulx, T. (eds) Optical Measurements, Modeling, and Metrology, Volume 5. Conference Proceedings of the Society for Experimental Mechanics Series. Springer, New York, NY. https://doi.org/10.1007/978-1-4614-0228-2_24
Download citation
DOI: https://doi.org/10.1007/978-1-4614-0228-2_24
Published:
Publisher Name: Springer, New York, NY
Print ISBN: 978-1-4614-0227-5
Online ISBN: 978-1-4614-0228-2
eBook Packages: EngineeringEngineering (R0)