Questions tagged [birefringence]
The birefringence tag has no usage guidance.
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What is the intuition behind $\vec{D}$ and $\vec{E}$ not being parallel for the extraordinary beam?
In anisotropic dielectrics, the electric field $\vec{E}$ and the displacement field $\vec{D}$ are no longer necessarily orthogonal. The mathematical reasons are the connection between the two fields:
$...
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How can a light ray have two different phase velocities?
In "Classical Theory of Electricity and Magnetism" by A. K. Raychaudhuri I found the following text regarding EM waves in anisotropic media (see p. 153):
$$ "\frac{n_1^2}{v^2-c_1^2} + \frac{...
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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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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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What is the meaning of a fiber cutoff wavelength when given as a range?
Many polarization maintaining fibers (for example Corning PM 1550) have a cutoff wavelength specified as a range (for example 1300-1440nm). What is the meaning of this range from the physics point of ...
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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 ...
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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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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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Birefringince in 2D array of masses and springs
Assume a 2D square array of masses with mass $m$ connected by springs with constant $\kappa$. Then the equation of motion for small perturbations in the plane of the array to the mass at $(l,n)$ is
$$
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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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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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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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How in Faraday rotator, changing magnetic field will change the refractive index of RCP and LCP?
Can anyone mathematically prove how in the faraday rotator, when we change the magnetic field direction, it will change the refractive index of Right circularly polarized (RCP) and Left circularly ...
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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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Physical origin of Kerr effect
I was wondering if someone could explain to me the physical (not mathematical) origin behind the Kerr effect and why it results in birefringence in materials.
Also, can the birefringence be introduced ...
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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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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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What is the refractive index of blood serum? [closed]
I'm looking for the refractive index of the blood containing the antibodies of covid-19.
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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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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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Metamaterial with index of refraction different in opposite directions
Has anyone created a mathematical model for a material whose index of refraction is different going right than it is for light traveling to the left?
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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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Vacuum Birefringence with alternating EM waves
I read [1] that in the presence of strong static electric or magnetic fields in vacuum the refractive index changes in such a way that there is a difference of refractive index between parallel and ...
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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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Vacuum birefringence
Many of the papers (e.g., this) dealing with nonlinear electrodynamics treat a theory's prediction of vacuum birefringence as undesirable, but don't explain why it would be undesirable. For example:
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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?
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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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What happens if polarized light passes through calcite or some other birefringent material?
every explanation of birefringence I find talks about unpolarized light entering Calcite, but what if I use a polarized light? Will that mean that as I rotate the crystal the light will disappear then ...
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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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optical homogeneity of organic thin films
Prior to further analysis (like variable angle ellipsometric spectroscopy) I check thin films of organic materials vacuum deposited on glass substrates for their optical homogeneity under lineraly ...
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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 ...
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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....