126
6 Light Scattering by Dielectric Bodies of Irregular …
Fig. 6.3 Radiation intensity
distribution for a multilayer
medium absorbing and
scattering light for specific
parameters θ = 0 ◦ , ϕ = 0 ◦ ,
ψ = 0 ◦ and a refractive
index of epidermis is
1.303 + 10 −3 i and the
refractive index of the dermis
is 1.301 + 10 −3 i; b
refractive index of epidermis
is 1.303 + 10 −4 i and the
refractive index of the dermis
is 1.301 + 10 −4 i
0
2
4
6
8
0
2
4
6
8
0
0.02
0.04
0.06
0.08
x
0
2
4
6
8
0
2
4
6
8
0
0.05
0.1
0.15
0.2
y
x
y
(a)
(b)
Figure 6.5a, b shows the normalized spectra of action of laser radiation on oxy- and
deoxyhemoglobin. The simulation of the action spectra of the laser radiation power
absorbed by oxyhemoglobin and deoxihemoglobin of blood is performed using the
theory of the T -matrix in the spectral range from 300 to 800 nm. The choice of this
spectral interval is dictated by the fact that in most available methods, the transparency
window in the wavelength range from 650 to 1200 nm is used for optical probing
of biotissues [28]. Note that the spectral interval from 400 to 600 nm is diagnostic
because the main absorption bands of blood (Sore band 420 nm, absorption bands α
and β of oxyhemoglobin at 545 and 575 nm) lie in this spectral interval.
The spectral dependences of the refractive indices of the dermis and epidermis
were described by the following expressions [29]:
n(λ) = 1.30904 −
434.60068
λ 2
+
1.60647 · 10
9
λ 4
−
1.28111 · 10
14
λ 6