Title :
Characterization of micro and nano layers using frequency domain laser-ultrasound
Author :
Grunsteidl, C.M. ; Roither, J. ; Veres, Istvan A. ; Berer, Thomas ; Burgholzer, Peter ; Murray, T.W.
Author_Institution :
Res. Center for Non-Destruct. Testing GmbH, Linz, Austria
Abstract :
The presented work deals with the characterization of thin coatings with the help of their acoustic dispersion relation. Surface acoustic waves are excited and detected by a laser-ultrasound setup. The setup applies a superheterodyne principle which allows detection up to 1 GHz. This method provides high signal-to-noise ratios at low optical powers. A numerical model and an optimization algorithm are used to characterize the layers by their thickness and elastic properties.
Keywords :
acoustic dispersion; acoustic noise; acoustic signal processing; dispersion relations; elasticity; frequency-domain analysis; optimisation; surface acoustic waves; ultrasonics; acoustic dispersion relation; elastic properties; frequency domain laser-ultrasound; numerical model; optimization algorithm; signal-to-noise ratios; superheterodyne principle; surface acoustic waves; thin coatings; Coatings; Dispersion; Frequency modulation; Frequency-domain analysis; Laser excitation; Measurement by laser beam; Surface acoustic waves;
Conference_Titel :
Ultrasonics Symposium (IUS), 2013 IEEE International
Conference_Location :
Prague
Print_ISBN :
978-1-4673-5684-8
DOI :
10.1109/ULTSYM.2013.0403
