Wavelength in the visible spectrum most strongly transmitted

[xamy]

Homework Statement

A camera lens (n = 1.29) is coated with a thin film of magnesium fluoride (n = 1.71) of thickness 87.0 nm. What wavelength in the visible spectrum is most strongly transmitted through the film?

Homework Equations

λ = 2nt/m

The Attempt at a Solution

λ = 2(1.71)(87E-9m)/(1) = 297 nm

Answer is not correct. Please point out the mistake. Thanks

 

[SammyS]

Homework Statement

A camera lens (n = 1.29) is coated with a thin film of magnesium fluoride (n = 1.71) of thickness 87.0 nm. What wavelength in the visible spectrum is most strongly transmitted through the film?

Homework Equations

λ = 2nt/m

The Attempt at a Solution

λ = 2(1.71)(87E-9m)/(1) = 297 nm

Answer is not correct. Please point out the mistake. Thanks

Look at how the refractive indices are related at each surface.