Abstract

Recent demand for rapid and non-invasive diagnostic techniques in medicine has initiated an extensive research in the field of optical diagnostics. Reflection of light from biological tissue is a typical multiple scattering phenomenon. The backscattered light from an incident short optical pulse will be broadened in time, and this broadening can be mathematically related to the large number of optical paths available in multiple-scattering media. Since the introduction of losses (absorbers) reduces the average path length, absorber-dependent changes in pulse propagation time can be used to calculate absorption coefficients. In contrast to continuous illumination techniques, pulse propagation methods can provide information on the distribution of scatterers and absorption in a single measurement.

© 1994 IEEE