Question

A material having an index of refraction of 1.35 is used as an antireflective coating on a piece of glass (n = 1.50). What should be the minimum thickness of this film in order to minimize reflection of 560 nm light?

Answer 1

Answer:

103.70 nm

Explanation:

The minimum thickness of the film is given by $t=\frac{\lambda }{4n}$ where $\lambda$ is the wavelength and n is the index of the refraction

We have n =1.35

Wavelength $\lambda =560nm$

So the minimum thickness of the film $t=\frac{\lambda }{4n}=\frac{560}{4\times 1.35}=103.70\ nm$