Sampaio A.L.,Polo Universitario Of Volta Redonda Uff |
Lobao D.C.,Polo Universitario Of Volta Redonda Uff |
Dos Santos P.A.M.,Institute Fisica UFF |
Silva L.,Polo Universitario Of Volta Redonda Uff |
Huguenin J.A.O.,Polo Universitario Of Volta Redonda Uff
Optics and Lasers in Engineering | Year: 2011
In this paper, we present a study of metallic surface roughness using the Hurst exponent calculated from speckle pattern. A set of samples was prepared using polishing techniques and the roughness was directly measured by means of an optical profilometer. To study the H exponent, an experiment was performed by illuminating the samples using an expanded laser beam and the surface image was captured by a CCD camera. We applied techniques of the Hurst exponent calculation, traditionally calculated from surface profile, in the digitalized speckle patterns generated by the rough surfaces. We showed a clear dependence of the H exponent on roughness of the samples. We demonstrated that this tool is very sensitive to defects in the surfaces and can be used for roughness control. © 2010 Elsevier Ltd. All rights reserved.