Phase detection in acoustic microscopy.

S F Levinson

doi:10.1177/016173469001200404

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Phase detection in acoustic microscopy.

S F Levinson

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Abstract

The scanning laser acoustic microscope provides a relatively simple means by which speed of sound data can be collected from biological specimens. By employing a phase detection circuit, phase-contour lines can be superimposed on acoustic micrographs and digitized for direct speed of sound calculations. Because of the existence of mild field non-uniformities, the phase reference must be mathematically modeled. This is accomplished by employing a polynomial function and simple linear regression. Scattering can be studied by using a frequency-selective "dark field" approach. Speed of sound maps are readily produced from the phase data by applying the simple geometric relationships of wave propagation; however the theoretical limitations of the technique must be kept in mind. Using this approach, useful data have been obtained.

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Acoustics Animals Anura Image Enhancement Image Processing, Computer-Assisted Lasers Microscopy Models, Theoretical Muscles Scattering, Radiation Signal Processing, Computer-Assisted Ultrasonics Ultrasonography Journal Article Research Support, Non-U.S. Gov't

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S F Levinson. 1990. Phase detection in acoustic microscopy.. https://doi.org/10.1177/016173469001200404

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