The CSF was either considered part of the brain, with the same absorption and scattering coefficients, or, more realistically, as a relatively clear medium with low absorption and scattering coefficients μ a = 0.04cm−1 and μ′ s = 0.1cm−1.
The clear pocket of CSF contributes to modification of the signal through the combined effects of very low absorption and scattering.
Low-coherence spectroscopy (LCS) is a method for simultaneous measurements of local attenuation, absorption, scattering and backscattering coefficient spectra in turbid media within the visible wavelength range (480 to 700 nm) [ 1– 3].
Poulton introduces absorption, scattering, colour due to "thin plates" (structural coloration), diffraction and refraction.
The main interactions exploited are absorption, scattering and fluorescence [ 7].
Absorption (scattering) can be explained using the characteristic parameter called absorption (scattering) coefficient μa (μs) which is defined as the probability of photon absorption (scattering) per unit path length in a medium.
The results indicate that, in addition to its demonstrated ability to degrade effectively many contaminants, its optical properties exhibit very low absorption and scattering properties.
In this wavelength range, there is an important biological transparency window in which water molecules exhibit low absorption and scattering of light; thus, light at these wavelengths can effectively penetrate deep into tissue [7].
Moreover, at 1064 nm, both melanin and water have low absorption and scattering in tissues [ 17– 20].
QDs that emit in the NIR region are suitable for biomedical applications because of low tissue absorption, scattering, and autofluorescence in this region which leads to high photon penetration in tissues [122, 123].
