We wish to coat flat glass (n = 1.50) with a transparent material (n = 1.25) so that reflection of light at wavelength 600 nm is eliminated by interference. What minimum thickness can the coating have to do this?

Short Answer

Expert verified

The minimum thickness of coating is1200nm

Step by step solution

01

Identification of given data

The index of refraction for coat flat glass is nc=1.50

The index of refraction for transparent material is role="math" localid="1663133484448" nc=1.25

The wavelength of light isλ=600nm

02

Understanding the concept

The index of refraction is the ratio of the speed of light in medium to speed of light in vacuum.

03

Determination of minimum thickness of coating

The minimum thickness of coating is given as:

t=λ2nc-nm

Substitute all the values in equation.

t=600nm21.50-1.25t=1200nm

Therefore, the minimum thickness of coating is1200nm

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