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Interference from thin film


Thin films can cause interference when light waves reflect off the top and bottom surfaces of the film. This interference can lead to changes in the intensity and color of the light that is transmitted or reflected.


When a beam of light passes through a thin film, some of the light is reflected at the top surface of the film, and some is transmitted into the film. As the transmitted light passes through the film, some of it is reflected at the bottom surface of the film and some of it continues to travel through the film. When the reflected light waves from the top and bottom surfaces of the film meet, they can interfere with each other constructively or destructively.

If the thickness of the film is such that the reflected waves from the top and bottom surfaces of the film are in phase (constructive interference), the reflected light will be more intense than if the waves were out of phase (destructive interference). This can result in a change in the color of the light that is reflected or transmitted through the film, as different colors of light have different wavelengths and therefore different interference patterns.


  1. Young's Double Slit Experiment
  2. Double Slit Experiment
  3. Diffraction
  4. Experiments

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