Reconstruction and time reversal in thermoacoustic tomography in acoustically homogeneous and inhomogeneous media
Reconstruction and time reversal in thermoacoustic tomography in acoustically homogeneous and inhomogeneous media
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DOI：
10.1088/0266-5611/24/5/055006
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发表时间：
2008-10-01
期刊：
影响因子：
2.1
通讯作者：
Nguyen, Linh
中科院分区：
文献类型：
--
作者：
Hristova, Yulia;Kuchment, Peter;Nguyen, Linh
本文首先比较讨论了最近的三种类型的方法来重建热声/光声层析成像的功能和局限性：反投影公式，本征函数展开和时间反演。后一种方法恰好是限制最少的。它被认为是在更详细的，E。G.这与介质的捕获特性有关。由于惠更斯原理的有效性，时间反演方法仅在奇数维恒定声速的情况下是准确的。下一个最佳情况是奇数维中的非捕获速度。作者提供了2D的例子，并讨论了恒定和可变（非捕获和捕获）速度的数值重建的特点，表明这种技术即使在最不利的情况下（可变，甚至在2D中捕获声速）也能令人惊讶地工作。特别是，一个“有限的看法”的效果，由于捕获观察和解释。最后，对声速恢复问题提出了初步的考虑。
The paper starts with a comparative discussion of features and limitations of the three types of recent approaches to reconstruction in thermoacoustic/photoacoustic tomography: backprojection formulae, eigenfunction expansions and time reversal. The latter method happens to be the least restrictive. It is then considered in more detail, e. g. its relation to trapping properties of the medium. The time reversal method is exact only in the case of a constant sound speed in odd dimension, due to validity of the Huygens' principle. The next best case is of non-trapping speed in odd dimensions. The authors provide 2D examples and discuss the features of numerical reconstructions for constant and variable ( both non-trapping and trapping) speeds, showing that this technique works surprisingly well even under the most unfavorable circumstances ( variable, and even trapping sound speed in 2D). In particular, a `limited view' effect due to trapping is observed and explained. Finally, an initial consideration of the problem of sound speed recovery is also provided.