An Experimental Study of Tomographic Imaging in Layered Media

  • Y. Q. Wang
  • R. A. Kline


Ultrasonic tomography has found its applications in material evaluation since the later 70’s. However, the techniques in this field are far less developed compared to their x-ray counterparts, which have been widely used in the medical community. One of the practical problems in acoustic tomography is that acoustic waves will not necessarily propagate along straight paths in a nonhomogeneous medium. The situation will be more complicated when material inhomogeneities are coupled with anisotropy as the approach is applied to composite media. In order to resolve the situation, one has either to tolerate the consequence of using straight line ray paths or to seek a way to correct the errors due to ray bending. Indeed, most of the previous work in this area has been based on the straight path assumption. As pointed out by Dines and Lytle[1], if the material inhomogeneity is not serious, the errors caused by straight path assumption can be safely neglected. However, in practice, situations may arise where serious inhomogeneities exist. Even with small inhomogeneities correction is highly desirable when accuracy is of particular concern.


Anisotropic Medium Aluminum Powder Material Inhomogeneity Straight Path Algebraic Reconstruction Technique 
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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Copyright information

© Plenum Press, New York 1993

Authors and Affiliations

  • Y. Q. Wang
    • 1
  • R. A. Kline
    • 1
  1. 1.School of AMEUniversity of OklahomaNormanUSA

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