Photon diffusion equation
- Photon diffusion equation
Photon diffusion equation is a second order partial differential equation describing the time behavior of photon fluence rate distribution in a low-absorption high-scattering medium.
Its mathematical form is as follows.abla(D(r)cdot
abla)Phi(vec{r},t)-vmu_a(vec{r})Phi(vec{r},t)+vS(vec{r},t)=frac{partialPhi(vec{r},t)}{partial t}where Phi is photon fluence rate (W/cm2), mu_a is absorption coefficient (cm-1), D is diffusion constant, v is the speed of light in the medium (m/s), and S is an isotropic source term (W/cm3).
It's main difference with diffusion equation in physics is that photon diffusion equation has an absorption term in it.
Application
Medical Imaging
diffuse optical tomography
External links
* [http://www.lrsm.upenn.edu/pmi Diffuse Optics Lab at University of Pennsylvania, Philadelphia, USA]
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