Non-contacting ultrasonics for visualizing and exploiting multiple scattering
نویسنده
چکیده
Using lasers as both sources and detectors we are able to quickly collect large amounts of ultrasonic data on rock samples without the disturbances caused by contacting transducers. Since we excite primarily surface waves, recording the wavefield on the surface is analogous to measuring the wavefield within the scattering medium. Thus we can visualize wavefields as they propagate through rocks by watching the influence of scattering on the surface waves. To extract quantitative information about the rock sample, we fit the intensity data to a radiative transfer model. From this fit we extract the mean-free-path of the scattering, which gives us a measure of the scattering strength of the sample.
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