Questions tagged [birefringence]
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42
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What causes polarised materials to change colour under stress?
Our physics teacher showed the class a really interesting demonstration. He used two polarised filters in opposite orientations, then he took some antistatic tape and stretched it under the two plates....
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Unexpected laser pattern through calcite crystal
I've bought a calcite crystal and tried to see birefringence by shining a laser through it.
I get a split spot in the centre of a sixfold pattern
The hexagonal pattern resembles a diffraction pattern,...
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Why do I see a rainbow when I look at Insulfilm with my sunglasses?
I'm wearing glasses with a sunglass clip-on. This means I have my regular glasses and, on top of them, I have a second pair of lenses that work as sunglasses and attach to my regular glasses using ...
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Skylight reflection shows birefringence patterns
I noticed that the skylight where I work looked white to me, but its reflection from the tiles below showed a colorful pattern. See the images below, and also a video that shows this effect from ...
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Torque on Quarter-Wave Plate
When circularly polarized light is passed through a quarter-wave plate, the plate experiences a torque. I understand this is true because angular momentum must be conserved, but I don't understand ...
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Why is Nicol prism cut at 68 degrees specifically?
Why not just some other angle but this specific one? Does it help in some way to polarize the ray?
I have tried searching everywhere, but they only show that the crystal is cut at an angle of 68 ...
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Why don't extraordinary rays follow Snell's law?
I understand that ordinary ray (O-ray) and extra-ordinary ray (e-ray) have different refractive indices.
This should mean O-ray and e-ray move with different velocities in a substance and they should ...
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Significance of colours in photoelasticity
I already checked similar question at Physics SE, but none gives me a clear answer, also it is a bit difficult for me to understand it from wikipedia as I couldn't find relating material to my ...
user65994
4
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Why are birefringence materials so rare?
By symmetry, most crystals will show birefringence. But the effect is very minute. So the question is actually, why is the birefrigence effect in most low-symmetry materials so small?
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What sort of polarizer is this?
I wanted to try to experiment with polarizers, trying the 3 polarizers 45 degrees from each other, and similar experiments. I ordered 10 sheets of the cheapest polarizing foil I could find on ...
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How could light from a TV screen refract when viewed through a helmet's transparent visor? [duplicate]
How could light from a TV screen refract when viewed through a helmet's transparent visor?
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Circular polarizer filter wavelength dependency?
I don't fully understand the circular polarizer filter (CPL) for my camera. It contains a linear polarizer and a quarter wavelength plate (QWP). The QWP causes a time delay between the ordinary and ...
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2
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Rotation of the image formed by the extraordinary ray upon rotating the calcite crystal
Let a black spot is drawn on a piece of white paper. If we place a transparent calcite crystal on top of the paper, we observe two non-coincident images of the black spot. This is due to the ...
- 11.8k
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3
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Why do birefringence materials have 2 refractive indices?
Why do birefringence materials have 2 refractive indices?
In other words, what causes the material to have 2 refractive indices?
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Direction of propagation of extraordinary wave inside a birefringent medium
I am reading Optics by Ajoy Ghatak, in which the author explains the phenomenon of double refraction in a calcite crystal using Huygens' principle. My query is in the analysis of the case of normal ...
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