Figure 3.

(A) The three-layer dielectric model used to calculate the evanescent electric field intensity $I_{\text{exc}}$ in the interspace between the cell and the glass substrate. (B, circle dots) $I_{\text{exc}}$ calculation for s-polarized light, plotted as a function of the axial distance $z_s$, for $z_0$ = 100 nm, $n_{\text{cyto}}$ = 1.37. (B, solid line) Fit according to a single exponential decay ($\text{exp}\left[-\left(z_s+z_0\right)/\kappa \right]$, where κ is given by Eq. 3). (C) Evolution of the effective refractive index as a function of the medium gap thickness $z_0$, plotted for different values of $n_{\text{cyto}}$. For all the simulations, θ = 65°, ${\lambda }_L$ = 488 nm, $n_g$ = 1.53, and $n_{\text{med}}$ = 1.336.