Fig. 2.

(a) Experimental dependences of the registered signal level on the excitation wavelength for finger skin $S_{\mathrm{bg}}$ and PTFE medium $S_{\mathrm{bg}}^{\mathrm{PTFE}}$; the separated components $S_{\mathrm{af}}$ and $S_{\mathrm{sc}}$ responsible for autofluorescence and scattering of the skin, respectively, are also shown; (b) measured ratio of the diffuse reflection coefficients of finger skin and PTFE medium $R_d^{\mathrm{PTFE}}/R_d$.