Dependences of quantities ϕ₁, R₂₁, R₂₃, I ⁽¹⁾ on parameters (a, c), d_1,3 (b, d) for various materials of layers 1, 3. The values of parameters are: (a, b), 0.5 (c, d); (b), −13 (d); d₂ = 39 nm (a, b), 156 nm (c, d); d_1,3 = 250 nm (a, b), 13 nm (c, d); λ = 0.63 μm (a, b), 0.6 μm (c, d). I ⁽¹⁾ = I ^TM (1) (z = d₁ + 0.5d₂) for all the graphs. The black horizontal dashed line in figs. a, b, c characterizes equality to 1 of the corresponding quantities.