The reflectance for s-polarized light is R s = | Z 2 cos ⁡ ⁡ θ θ i − − Z 1 cos ⁡ ⁡ θ θ t Z 2 cos ⁡ ⁡ θ θ i + Z 1 cos ⁡ ⁡ θ θ t | 2 , while the reflectance for p-polarized light is R p = | Z 2 cos ⁡ ⁡ θ θ t − − Z 1 cos ⁡ ⁡ θ θ i Z 2 cos ⁡ ⁡ θ θ t + Z 1 cos ⁡ ⁡ θ θ i | 2 , where Z 1 and Z 2 are the wave impedances of media 1 and 2, respectively.