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Thanks for the link, really interesting. I guess it only gets more complicated when you sub-categorise scattering into different 'type', then we're back to reflect, refract etc. It's as simple or complicated as you want it to be, but it's nice to know it can be simple :icon_biggrin: 

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Antireflection coatings operate by destructive interference. 2 waves will destruct if 180 degrees out of phase - where is the scattering in this?

Besides just offering someones Youtube video what are your views and understanding on these optical phenomenon you post up?

Explain why this is all scattering. Explain the principal and theory behind the video you have posted.

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The cool deranged dude in the video doesn't say interference is scattering. He writes and says at the beginning (00:31) that optics is the study of interaction of light with matter, but interference is interaction of light with itself, quite something else. Thus optics is indeed only various forms of scattering.

Edited by Ben the Ignorant
typo
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On ‎21‎/‎09‎/‎2017 at 13:51, Ben the Ignorant said:

The cool deranged dude in the video doesn't say interference is scattering. He writes and says at the beginning (00:31) that optics is the study of interaction of light with matter, but interference is interaction of light with itself, quite something else. Thus optics is indeed only various forms of scattering.

Interference is the interaction of light with the sides of an aperture (for example.)

Interference is definitely a part of optics (for example zone plates and other more fancy flat lenses), if he says otherwise he's wrong.

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I see how you could equate interference with diffraction because they often happen together, but they are two distinct things. Interference is waves adding up or canceling each other, which could occur in the vacuum of outer space where there is no material object to cause diffraction between the sides of an aperture.

And if interference is produced in the void of space, it's called a particle physics phenomenon, or a wave physics phenomenon, but not an optical one.

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13 hours ago, Ben the Ignorant said:

 

And if interference is produced in the void of space, it's called a particle physics phenomenon, or a wave physics phenomenon, but not an optical one.

I feel that the video is slightly confusing. In the video, 'optics' is defined as the study of how light interacts with matter. This interaction is then explained as 'scattering'. 'Scattering' is a huge subject of which there are a great many different cases to consider, this is all glossed over in the video.  To make sense of 'optics' when defined like this is difficult.

'Geometric optics' on the other hand has some  simplifying assumptions which although fall short of the complete picture of light, do in fact provide a useful approximation of what happens with lenses, mirrors etc. It is assumed that light propagates as a ray and that the size of any mirrors/lenses are large when compared to the wavelength of light.

With these simplifying assumptions, Fermat's Principle of Least Time describes geometric optics perfectly. This one principle describes everything. Geometric optics in a sense is in fact simple....

https://en.wikipedia.org/wiki/Fermat's_principle

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