All Questions
Tagged with optics wavelength
149
questions
2
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3
answers
732
views
Why viruses cannot be seen?
With the coronavirus pandemic, a lot of websites are publishing articles about viruses. In particular, I've seen some of these stating that viruses cannot be seen because they are so tiny they cannot ...
- 585
0
votes
1
answer
58
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Sun light and leaf color
Wien's displacement law :
$\lambda_{peak}T=2.898\times 10^{-3}m\cdot K$
Temp of sun = 5000
so sun radiate green wave in max volume.
but atmosphere of earth refract sun light and blue wave is max ...
- 121
11
votes
5
answers
8k
views
Intuitive explanation for why blue light is refracted more than red light? [duplicate]
I understand the equation explaining angles of refraction related to wavelengths. But I'm looking for a more intuitive approach/visual explanation? Perhaps related to QM?
- 799
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1
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376
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Why is the two-term form for the Cauchy equation sufficient?
The general Cauchy equation for the relationship between refractive index and wavelength is given by,
$$n = A + \frac{B}{\lambda^{2}}+\frac{C}{\lambda^{4}}+...,$$
but this is often approximated to
$$...
- 1
1
vote
3
answers
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Why is the next minimum $\lambda$ from central maximum in the derivation of the Rayleigh criterion for a diffraction grating?
I am struggling to understand part of the derivation for the Rayleigh criterion, which states that
"Two images are just resolvable when the center of the diffraction pattern of one is directly over ...
- 2,470
0
votes
2
answers
189
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What is considered the frequency (and wavelength) of guided waves in a waveguide?
In a rectangular waveguide with sides of length $a$ and $b$, the dispersion relation is
$$\beta^2 =\omega^2\mu\epsilon=\beta_z^2+\beta_x^2+\beta_y^2=\beta_z^2+\beta_s^2.$$
So we have
$$\beta_z = \...
- 27
0
votes
2
answers
103
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Explanation: When light waves propagate through and around objects whose dimensions are much greater than the wavelength of the light,
My textbook, Fundamentals of Photonics, 3rd edition, by Teich and Saleh, says the following:
When light waves propagate through and around objects whose dimensions are much greater than the ...
- 889
0
votes
1
answer
3k
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Diffraction grating angle
Why have they taken the angle to be 90 degrees?
And why have they used only one of the wavelengths provided?
can you explain in layman terms?
user204223
1
vote
3
answers
160
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Are interference patterns the basis for all other measurements of light frequencies and wavelengths?
The wavelength or frequency of monochromatic electromagnetic radiation is determined indirectly by calculations on the interference or diffraction pattern. These patterns are generated by gratings, ...
- 10.6k
4
votes
4
answers
3k
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How exactly is white light a combination of several wavelengths? [duplicate]
I have read that light is an electromagnetic wave. Every ray of light has a specific wavelength. The colour perceived by any observer is dependent upon the wavelength of the incident light.
What I ...
- 170
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votes
3
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183
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Do waves of light overlap?
Hopefully I can phrase this question so that it can be understood and not appear to be entirely uneducated.
From what I understand when light hits an object it reflects that light toward you. Let's ...
1
vote
4
answers
2k
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Is there 100% pure white? [duplicate]
Is it possible to have an object 100% pure white without sky blue or sun color tinting the pure whiteness of the photons reflecting/deflecting off an object? Are there any lights that can produce pure ...
- 113
0
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0
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54
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Why frequency does not change when light passes through the denser medium? [duplicate]
as far as I noticed always people in physics have a predefined assumption that frequency is constant. whereas we know that the c is the outcom of product of wavelength and frequency. we have different ...
1
vote
2
answers
1k
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Dispersion through Glass Slab
My questions related Dispersion through Glass Slab:
Why does a parallel surface makes a difference?
Why is that light do get disperse in a prism and a glass slab at surface one but at backs normal ...
user232991
1
vote
1
answer
258
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Variation of Refractive index
We know that refractive index, for any medium,
$$n=1/\sqrt{\epsilon\mu}.$$
Also, according to Cauchy's relation
$$n=A+B/\lambda^2,$$
where $A$ and $B$ are constants related to the medium.
...
- 257