All Questions
Tagged with optics optical-materials
155
questions
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Can an optical medium be lossless and dispersive?
Occasionally, I come across the phrase "lossless dispersive linear optical medium". How can such a medium be possible mathematically? I mean the real and imaginary parts of the electric ...
- 437
11
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2
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2k
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What percentage of light gets scattered by a mirror?
Sunlight strikes a mirror at a 45 degree angle. The vast majority of light will be reflected about the normal. Some light will be absorbed by the mirror. Some light will be transmitted through the ...
- 820
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1
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84
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Light splitting plastic film in phone display screen
I was recently taking apart a button-press phone (like this one) and right under the glass protective screen was a thin plastic film.
This is what happens when I place it over a single dot:
As far ...
- 145
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0
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30
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Mixed configuration of magneto-optical kerr effect
Typically there are three types of magneto-optical Kerr effect experiments: Polar, longitudinal, and transverse. These three geometries yield very different results regarding what is measured (...
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45
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How can a greater than 1 reflectance coefficient be explained in $\rm SiC$-$\rm SiO_2$ interface?
I ran a simulation using the Transfer Matrix Method to plot the R,T and A curves for a SiC->SiO2 interface. There's a region of incident energies where the |r|^2 I get is higher than 1 and the ...
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104
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Why can you not create a LED equivalent by illuminating a colored plastic casing?
I would first like to apologize if this is a dumb question.
I understand the physics of color sufficiently well. You have an incoming photon that intercepts an electron on the atom, the electron gets ...
- 173
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27
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Knowing the optical path difference, how do I calculate the resulting image?
Let's say I'm taking a picture through a cube of some material where the index of refraction varies in a known way, such as a GRIN lens. I can calculate the optical path difference as a function of ...
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-1
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Transmittance of one material through a multilayer
Good morning,
I have the transmittance and the reflectance spectrum of PET (Polyethylene terephthalate) and I also have the transmittance and the reflectance spectrum of PET + Copper (50 nm). I would ...
- 31
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37
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What is a true delay line and is there possibly a false delay line?
I'm reading "Silicon nitride passive and active photonic integrated circuits: trends and prospects" and one of discussed application of $\rm SiN$ is "true delay line". All the ...
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1
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56
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Do mirrors (with metal surfaces) show TIR (Total Internal Reflection)?
[Not a duplicate! Also, the answer to a similar question was unsatisfactory]
I was digging into why we don't use mirrors in place of fibre optics cables. Majorly, the answers were as follows:
It's ...
- 153
4
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1
answer
668
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How do optical fibres work with high critical angles?
The critical angle is given by:
c = arcsin(n2 - n1)
For a typical optical fibre, it says on the web that refractive index (n2) for cladding is higher than that of the glass core (n1) but it's only a ...
- 153
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168
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In a uniaxial crystal, what determines the optical axis, extraordinary axis, and ordinary axis?
In a uniaxial crystal there is an optic axis, an extraordinary axis, and an ordinary axis. The optic axis is not the direction in which we plan to propagate light. The light is propagating in a ...
0
votes
1
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59
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What happens when screen is not placed where Image is focused but elsewhere?
When we try to form a real image on a screen by a convex lens, we place the screen at a distance where the image is focused. But if we try to place the screen at a distance less than the distance ...
- 187
1
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1
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56
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Why are things reflective, absorbent, transparent etc? [duplicate]
What determines whether a material reflects, absorbs or transmits a certain wavelength of light? Just a layman's question.
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230
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Why does light either get reflected, absorbed, or passes through a surface or obstacle?
For each of these 3 cases, I'm having trouble understanding...
If light is reflected, does that mean that there was not sufficient energy by the photons to excite the electrons of the surface to ...
- 195