Theoretical analysis of frequency and time-domain methods for optical
characterization of absorbing and scattering media
(2005)Abstract
Measurements of the temporal distribution of radiation transmitted
and/or reflected by an absorbing and scattering medium, subject to
a very short pulse of light, are likely to provide information on
radiative properties of the sample. However, this procedure requires
precise solutions of the transient radiative transfer problem as
well as appropriate nano/pico response time from detection devices.
In this work, a different approach is investigated: the transient
radiative transfer problem is solved in the space-frequency domain
using a discrete ordinates-finite volume method and is shown to provide
accurate results. Recent research work has proposed promising optical
diagnostic techniques based on a radiation beam for which intensity
is modulated. As a result, a preliminary sensitivity analysis is
performed to determine some optimal parameters for the design of
frequency-modulation based optical diagnostic techniques. The novelty
here also arises from the application of the space-frequency method
to media that are not necessarily optically thick.