Table 1.

Skin optical properties ($\lambda$ is given in nm).

Tissue	Parameter	Value	Ref.
Epidermis	Optical absorption (${\mathrm{cm}}^{-1}$)	${\mu }_{\mathrm{ae}}=[C_{M}6.6({\lambda }^{-3.33})({10}^{11})]+(1-C_M)\{0.244+85.3[\exp (-\frac{\lambda -154}{66.2})\left]\right\}$	50
	Melanosome fraction $C_M$	6% for Caucasian skin, 40% for pigmented skin	51
	Reduced scattering (${\mathrm{cm}}^{-1}$)	${\mu }_s^{\prime }=68.7(\frac{\lambda }{500}{)}^{-1.16}$	52
	Refractive index	1.42–1.44 (700 to 900 nm)	53
	Anisotropy	0.95–0.8 (700 to 1500 nm)	54,60
	Thickness	0.1 mm
Dermis	Optical absorption (${\mathrm{cm}}^{-1}$)	${\mu }_{\mathrm{ad}}=C_B{\mu }_{\mathrm{ab}}+(1-C_B)\{0.244+85.3[\exp (-\frac{\lambda -154}{66.2})]\}$	50
	Blood volume fraction $C_B$	0.2% to 7%	55
	Reduced scattering (${\mathrm{cm}}^{-1}$)	${\mu }_s^{\prime }=45.3{\left(\frac{\lambda }{500}\right)}^{-1.292}$	52
	Refractive index	$n=A+\frac{B}{{\lambda }^2}+\frac{C}{{\lambda }^4}$, where $A=1.3696$, $B=3.9168\times {10}^3$, $C=2.5588\mathrm{x}{10}^3$	53
	Anisotropy	0.95 – 0.8 (700 to 1500 nm)	54,60
	${\mathrm{sO}}_2$	40% to 100%	55
Blood	Optical absorption (${\mathrm{cm}}^{-1}$)	${\mu }_{\mathrm{ab}}=C_{\mathrm{Hb}}{\alpha }_{\mathrm{Hb}}+C_{{\mathrm{HbO}}_2}{\alpha }_{{\mathrm{HbO}}_2}$	50
	Reduced scattering (${\mathrm{cm}}^{-1}$)	$22{\left(\frac{\lambda }{500}\right)}^{-0.66}$	52
	Refractive Index	1.36 (680 to 930 nm)	56
	Anisotropy	0.994 (roughly constant for variant wavelength and ${\mathrm{sO}}_2$)	57,58
Hypodermis	Optical absorption (${\mathrm{cm}}^{-1}$)	1.1 at 770 nm, 1.0 at 830 nm	59
	Reduced scattering (${\mathrm{cm}}^{-1}$)	20.7 at 770 nm, 19.6 at 830 nm	59
	Refractive index	1.44 (456 to 1064 nm)	54
	Anisotropy	0.8 (700 to 1500 nm)	60