Spatially Offset Raman Spectroscopy—How Deep?

Spatially offset Raman spectroscopy (SORS) is a technique for interrogating the subsurface composition of turbid samples noninvasively. This study generically addresses fundamental question relevant to wide range SORS studies, which how deep probes any specific spatial when analyzing sample or, in turn, what magnitude one should select probe depth. issue addressed by using Monte Carlo simulations, under assumption negligible absorption, establishes that key parameter governing extent probed zone point-like illumination and collection geometry reduced scattering coefficient medium. can either be deduced from literature data or directly estimated measurement evaluating intensity profile multiple offsets. Once this known, determined simulation results presented here. The proposed method was tested experimental on stratified signal detected thin layer moved through stack layers both non-absorbing absorbing samples. simple methodology provides important additional information measurements with direct relevance applications including biomedical, pharmaceutical, security, forensics, cultural heritage.