The finite element model for the propagation of light in scattering media: A direct method for domains with nonscattering regions.
252 - 264.
We present a method for handling nonscattering regions within diffusing domains. The method develops from an iterative radiosity-diffusion approach using Green's functions that was computationally slow. Here we present an improved implementation using a finite element method (FEM) that is direct. The fundamental idea is to introduce extra equations into the standard diffusion FEM to represent nondiffusive light propagation across a nonscattering region. By appropriate mesh node ordering the computational time is not much greater than for diffusion alone. We compare results from this method with those from a discrete ordinate transport code? and with Monte Carlo calculations. The agreement is very good, and, in addition, our scheme allows us to easily model time-dependent and frequency domain problems. (C) 2000 American Association of Physicists in Medicine. [S0094-2405(00)00901-9].
|Title:||The finite element model for the propagation of light in scattering media: A direct method for domains with nonscattering regions|
|Keywords:||light propagation, diffusion, voids, transport equation, finite element method, TIME-OF-FLIGHT, PHOTON MIGRATION, DIFFUSION, TRANSPORT, TISSUE, APPROXIMATION, BOUNDARY|
|UCL classification:||UCL > School of BEAMS
UCL > School of BEAMS > Faculty of Engineering Science
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