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Transmission Imaging: Forward Scattering and Scatter Reconstruction

  • C. H. Chou
  • B. T. Khuri-Yakub
  • G. S. Kino
Part of the Acoustical Imaging book series (ACIM, volume 9)

Abstract

We give here a theory for the nature of the image if produced by the scanning laser acoustic microscope (SLAM) at a surface in the far field of the flaw. A physical model and an exact calculation of scattering of longitudinal acoustic waves by spherical defects are presented. The total displacement field (incident plus scattered) is evaluated at planes at a distance from the defect by using the Ying and Truell scattering theory. It is found that evaluation of the exact type and size of a defect is not possible from direct observation of the total field. A holographic type reconstruction technique using either 2-dimensional Fourier transform, or Rayleigh-Sommerfeld diffraction formulae, was used to reconstruct the field at the location of the defect from a knowledge of the field at an observation plane, a distance z away from the defect. It is found that accurate defect characterization can be made using this reconstruction technique.

Keywords

Scattered Field Total Field Transmission Imaging Observation Plane Spherical Void 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • C. H. Chou
    • 1
  • B. T. Khuri-Yakub
    • 1
  • G. S. Kino
    • 1
  1. 1.Ginzton LaboratoryStanford UniversityStanfordUSA

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