Lesson: Thin Film InterferencePhysics
In this lesson, we will learn how to calculate the thickness of thin films that produce interference by the reflection of light from the layers’ surfaces.
Sample Question Videos
A thin film with a refractive index of 1.32 is surrounded by air. What is the minimum thickness of this film that minimizes the reflection of normally incident light of wavelength 500 nm?
After a minor oil spill, a thin film of oil, with a thickness of 450 nm, floats on the surface of the water in a bay. Use a value of 1.40 for the refractive index of the oil, and a value of 1.33 for the refractive index of the water. What is the predominant wavelength seen by someone flying in a helicopter overhead?
A transparent film of thickness 250 nm and index of refraction 1.40 is surrounded by air. A beam of white light that is incident almost normal to the film undergoes destructive interference when reflected. What wavelength in the beam undergoes destructive interference at reflection from the film?