Frequency Analysis of Laser-generated Pressure Waves using Wavelet Transforms
نویسندگان
چکیده
This paper deals with the analysis of the pressure wave signals generated in an aluminium-stepped sample. The ultrasonic signals are generated using pulsed Nd-YAG laser and detected using a He-Ne Heterodyne interferometer. The pressure wave signals at constant laser power are recorded at various directions with respect to source laser direction and the intensity of various frequency components present in these pressure wave signals are estimated with the help of coefficient lines in theirs wavelet transforms. The variation of the intensity of individual frequency components with detection direction and the intensity variation with signal frequency at a given detection direction are studied and the results are presented.
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