We study photon diffusion in a one-dimensional model foam composed of thin films and Plateau borders. Each thin film or Plateau border is characterized by its own intensity transmittance. We relate $l_{\text{Foam}}^{\ast }$, the transport-mean-free path of photons diffusing in the foam, to the foam microstructure. Denoting by $l_{\text{Film}}^{\ast }$ $\left(l_{\text{PB}}^{\ast }\right)$ the transport-mean-free path of photons in a medium composed only of thin films (Plateau borders), we find $1/l_{\text{Foam}}^{\ast }={\phi }_F/l_{\text{Film}}^{\ast }+{\phi }_P/l_{\text{PB}}^{\ast }$. Here ${\phi }_F$ and ${\phi }_P=1-{\phi }_F$ are the fraction of films and Plateau borders, respectively.

• Received 8 September 2010

DOI:https://doi.org/10.1103/PhysRevE.82.041131