The wave theory says that every point on the wavefront is taken as a source of secondary spherical wavelets. Now what I want to know is
what does this actually mean?
As every point is producing waves will they not interfere with one another? Will we be seeing an interference pattern?
I am just unable to visualize it in my mind.
Can somebody please explain it to me what the theory is all about? And do it in a simple way so that I could visualize it better.
[Physics] Huygens’ wave theory
diffractionhuygens-principleinterferencesuperpositionwaves
Best Answer
Basically Huygens Principle is just a way that was envisioned in the 17th century to describe how wave behaves and is understood as in the following picture. Each point on the wavefront radiates spherical waves which interfere to preserve it during propagation.
This picture is inspired from Rayleigh Scattering where the emitters are actually all the electrons of the atoms in a material which react to the electric field.
Though Huygens principle is not completely correct, in particular one needs to add an obliquity factor to prevent backward propagation. Moreover for large wavelength on small aperture the Huygens principle is definitely no longer valid.
To sum up I would say that Huygens principle is a convenient way to describe wave propagation and particularly diffraction which happens to be adequate in many cases. However this principle is not fundamentally right.