A finite difference approach to acoustic tomography in anisotropic media

In this paper, a finite difference formulation for acoustic wave propagation is used as the basis for tomographic reconstruction. This approach offers some interesting advantages over traditional, ray based methods; particularly for anisotropic media. Since this approach provides information on the full acoustic field (not individual rays), it offers a conventional way to incorporate beam skew and ray bending phenomena directly into the problem formulation. Here, we present a tomographic reconstruction algorithm which is adapted from the algebraic reconstruction technique (ART) to take full advantage of the finite difference formulation of the problem. Results are presented to illustrate the utility of this approach.