Abstract

We discuss the effect of geometry and boundary conditions in the determination of scattering and absorption constants by using methods of time resolved spectroscopy. In particular, there is a subtle difference between absorption conditions and radiation conditions, that is, in which photons are not absorbed at the surface but may pass through unhindered. These effects may not be neglected near the surface nor in backscattering type experiments, which are inherently more sensitive to the boundaries than transmission experiments. These effects are also important in imaging using diffusive wave spectroscopy, because of the sensitivity of the inferred spatial structure with respect to the observed transmission data. This is especially true when sources and detectors are not placed within the scattering medium and photons must traverse the boundaries twice.

© 1992 Optical Society of America