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Tagged with refraction optics
916
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Luneburg lens in a medium
A Luneburg lens is a spherical lens with a gradient refractive index. It has the interesting property that light coming from focal length of infinity will be focused on the surface of the lens.
The ...
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Diffraction when the wavefront is not parallel to the plane
I am studying Feynman's chapter on the origin of the index of the refractive index (see this link).
If I am not mistaken, what he does is to prove that when a wave enters a medium (modelled as a ...
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Difficulty in understanding an optics question
So here's the question:-
A thin film of transparent material of refractive index $1.52$ and thickness $0.42\ \rm \mu m$ forms a thin coating on glass of refractive index $1.60$. It is viewed by ...
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What is meant by optical density?
I’m trying to research about optical density for a school task, but the definitions online are confusing me.
From what I’ve gotten, optical density is:
how much the intensity of light is increased or ...
- 207k
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Snell's law in materials having negative permittivity only?
We have reverse Snell's law in negative index materials (having negative permittivity and permeability). If we have a material with only negative permittivity , then can we also have reverse Snell's ...
- 207k
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Under which circumstances is Snell's law applicable?
For a few years I have been tinkering with a numerical solver for light propagation. I stuck with the Helmholtz equation in the paraxial approximation because of lasers.
$$\partial_z f= \frac{i}{2k}\...
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How mirror can be used to explain the appearance of mirages?
Since mirage, in optics, the deceptive appearance of a distant object or objects caused by the bending of light rays (refraction) in layers of air of varying density. The normal path of light rays ...
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Most generic form of refractive index tensors
The refractive index of a material is in general a $3x3$ tensor (as in the case of birefringent crystals). From literature, it seems that in the case of transparent crystals, this tensor is in general ...
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Huygens' principle and the laws of reflection/refraction
As I understand the Huygens principle, all points on the wavefront are sources of secondary spherical wavelets and the tangent to these wavelets will form new wavefront. This is used to prove the ...
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Relating Brachistochrone problem to Fermat's principle of least time [closed]
When I came across the Brachistochrone problem, my teacher said we could relate it to Fermat's principle of least time.
So, we could make many glass slabs of high $\mathrm dx$, and every slab has a ...
- 207k
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At which wavelengths do photons behave like X-ray?
Hard X-rays of wavelengths of about an angstrom are very different than regular lights in a way that they can’t be reflected or refracted, which means their refractive index is always close to 1 ...
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Is there a good quantum explanation of refraction? [duplicate]
I'm aware of the classical explanation of refraction which deals with light being a wave that gets "slowed" down while passing from a medium to another. One problem that I have with this ...
- 207k
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What's at the end of a rainbow?
I recently saw a video where someone saw the end of a rainbow as it went into a lake. How is this even possible considering the fact that rainbows have no ends and are circular in nature?
Edit: I ...
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What does the optical Hamiltonian mean?
So I was trying to demonstrate Snell's law with Hamilton's equations, and when I got the Hamiltonian:
$$H = -\sqrt{n^2-p_{1}^2-p_{2}^2}.$$
I had a question about what this Hamiltonian indicates. I ...
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Can apparent depth be equal to real depth in any case?
Also does the depth of a tank decrease or remain same when viewed normally from above
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