Constructive interference condition:
Both sides of the film have a rare medium.
Such a case allows for 180° phase shift whenever the light waves strike a denser medium.
Thin-film interference is responsible for the fact that certain birds and inspects can appear different colors. Consider a very thin layer of oil (n=1.30) stretched the wisps of a bird feather, so that it has air on either side. Assume that the oil layer has uniform thickness t.
When you look at the feather with normal incidence, it strongly reflects green light of wavelength 500 nm. What is the minimum possible thickness of the oil layer?
Frequently Asked Questions
What scientific concept do you need to know in order to solve this problem?
Our tutors have indicated that to solve this problem you will need to apply the !! Thin-Film Interference concept. If you need more !! Thin-Film Interference practice, you can also practice !! Thin-Film Interference practice problems.