Question

Calculate the reflectivity from acrylic plastic (cheap camera lenses) at normal incidence. The refractive index is 1.50

Answer 1

For normal incidence we have the reflectivity defined as,

And transmittivity as, T such that R + T = 1. Here, n₁ is the refractive index of the medium from where the light is falling on the medium of refractive index n₂ from where the light is being reflected.

Here, n₁ = 1 and n₂ = 1.50

So,

So, the reflectivity from acrylic plastic at normal incidence is 0.04 or 4%. That means the major part of the light is transmitted.