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An Ultrasonic Imaging System for Three-Dimensional High-Resolution Defect Imaging

  • K. Mayer
  • R. Marklein
  • K. J. Langenberg
  • T. Kreutter
Chapter
Part of the Review of Progress in Quantitative Nondestructive Evaluation book series

Abstract

Quantitative ultrasonic imaging requires algorithmic data processing to yield the object function of a penetrable scatterer or the singular function of a perfectly scattering geometry, respectively. If either broadband pulse-echo or pitch-catch data are available on a closed measurement surface surrounding the scatterer completely, it can be shown that diffraction tomographic data processing in the widest sense is a solution of the linearized inverse scattering problem, i.e., if either the Born or Kirchhoff approximation can be tolerated in the NDE application under concern[1,2]. A particular representative of diffraction tomography called FT-SAFT for Fourier Transform Synthetic Aperture Focusing Technique has been implemented on an array processor for 3D defect imaging utilizing complementary Golay sequences[8] as transmitted signals to improve the signal-to-noise ratio and therefore, via deconvolution, the axial resolution. Data acquisition, storage, processing and sophisticated graphics display is controlled by an IBM-PC. In [3] the system as well as its theoretical background is described in detail, hence, only a brief and qualitative account is given here.

Keywords

Inverse Scattering Array Processor Diffraction Tomography Singular Function Equivalent Source 
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

© Springer Science+Business Media New York 1990

Authors and Affiliations

  • K. Mayer
    • 1
  • R. Marklein
    • 1
  • K. J. Langenberg
    • 1
  • T. Kreutter
    • 1
  1. 1.Dept. Electrical EngineeringUniversity of KasselKasselGermany

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