All Questions
Tagged with optics birefringence
32
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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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"Extraordinary polarization" in a birefringent optical medium
In Nonlinear Optics by R. W. Boyd, I came across the following sentences about light polarization in an uniaxial birefringent medium:
Light polarized perpendicular to the plane containing the ...
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1
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Ray separation in waveplates
In a birefringent medium, the ordinary and extraordinary rays have different Pointing-vector directions and, therefore, different propagation directions, since the direction of the Poyting-vector ...
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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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Need help with experimental setup to measure Birefringence [closed]
First message here, sorry if this is scrappy:
I am looking to measure the birefringence of multiple crystalline structures (calcite, ice, etc), and came across this methodology:
Shine a laser at ...
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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 ...
8
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2
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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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11
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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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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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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 ...
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Orienting birefringent crystal the right way in an interferometer
I'm working in a lab that involves transforming the polarization state of one beam of light in an interferometer via a Barium Borate (BBO) birefringent crystal. As the polarization state is altered ...
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149
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What can be the possible causes for variation in stress-induced birefringence in an isotropic material?
Birefringence is the phenomenon of a material having a refractive index that depends on the polarization and propagation direction of light. When an unpolarized light passes through such a material, ...
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1
answer
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Refractive Index Ellipsoid for Circular Birefringence Materials
When light travels through an anisotropic medium, its refraction may depend on both its polarization and propagation. Such materials may be classified in terms of their (Linear) Birefringence as ...
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Refractive indices of liquid crystal
Refractive indices of liquid crystal • The birefringence is critical to the optical properties of the liquid crystal and underlies many of the applications of liquid crystals. • By reorienting the ...
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Birefringence in uniaxial materials
In linear optics, when treating anisotropic uniaxial materials we get the frensel equation
this equation gives us two solution for n. My problem is that according to Snell's law, if I have two ...
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2
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503
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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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Birefringent materials and Maxwell equation
Maxwell's equations define the speed of light in a given medium at a given point through the equation:
$$\frac{\partial^2E}{\partial t^2}=\mu\epsilon\nabla^2E$$
so according to it, the speed of light ...
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2
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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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2
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1
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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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Birefringent filters: Showing that phase shift is inversely proportional to wavelength from my data
I started out by taking two sets of data for the crossed and parallel setup without the birefringent filter. The crossed setup being when destructive interference occurs and the parallel being ...
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1
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Why do we need cross-polarised light for observing conoscopic interference patterns?
I've performed some experiments for projecting conoscopic interference patterns. In some set-ups are used two circular polarizers one before and one after the birefringent crystal. I can imagine that ...
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Does the polarized light lose intensity when it crosses a birefractive crystal?
If a beam of light coming from a natural source passes through a polarizer and then through a birefringent crystal, does the intensity with which it left the polarizer change?
6
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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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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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What does the refractive index for e.g. alpha mean?
When I look for some materials like https://en.wikipedia.org/wiki/Barium_sulfate and want to extract the refractive index then there is written: (nD)=1.636 (alpha). And sometimes also for beta and ...
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Birefringent properties in Mylar films
Does Mylar film has birefringence properties? I am unsure about this and would like to know the reason behind its properties.
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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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Birefringent filter, optical path length difference?
In 'The Light Fantastic' by Kenyon, I.R. (p424), it is said that for a birefringent material inclined at Brewster's angle and who's optical axis lies in the plane of the plate, we have an optical path ...
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1
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Application of Snell's law for an extraordinary wave?
I have read [1] that when the light enters a birefringent material with optical axis perpendicular to the plane of incidence that the angle of refraction of the extraordinary wave can be found by ...
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1
answer
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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
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6
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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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