What is Polarisation: Definition and 122 Discussions

IPS (International Pol Scale) is a price adjustment scale described in the rules of the Sugar Association of London. It defines incremental price premiums and penalties applied to sugar above 96 degrees polarisation. This scale equates that the sugar contains 96% sucrose'

View More On Wikipedia.org
1. Total Internal Reflection and Transmitted Wavelength

In my electrodynamcis assignment I'm being asked to derive the wavelength of the normally polarised wave transmitted through a glass/air interface as a function of ##n_1## (the refractive index of the first medium) using the concept of phase continuity and the fact that maxima should be equal at...
2. B Bell inequality test without polarisation?

Was trying to understand the inequality test. The only article ever that I've found that explains it simply is the 1981 article, Bringing home the atomic world: Quantum Mysteries For Anybody. All other explanations require trust and understanding of polarisation, which is a huge deal. So i now...
3. I What happens when circular polarization meets a diagonal polarizer?

I'm finding what seems to be conflicting information on this question and could really use some help. It's my understanding that circularly polarized light is composed of two perpendicular linearly polarized components with a 90 degree phase shift between them. When considered individually...
4. Can Polarised Light Enhance Black and White Photography?

I am a 60 year old tinkerer who enjoyed science at school and studied architecture. Now I make things and enjoy having ideas and experimenting with them. I came here to ask a question about optics, polarisation and old school black and white film stuff
5. I Expose a Hidden Message w/ Polarisation Filters

I want to expose a very fine grain film where an image disguises a message but when viewing the through polarising filter allows the message to be revealeded. I envisage exposing the B & W image that is light by light polarised through a positive mask of the message and simultaneously a negative...
6. I Mirror rotates any polarisation by 90°?

Over each eye is a linear polariser and they are orthogonal to each other. So I conclude from the experiment that the polarisation must have been rotated by 90° by the mirror. That reminded my of phase plates but they only work because their refractive indix depends on the angle. Along two...
7. I Curious formula for elliptical polarisation

Recently, I have been playing with polarisation microscopy and the measuring of elliptical polarisation. Standard treatments, like that in Born and Wolf, are usually a mayhem of all kinds of trigonometric functions. Now I derived a nice relation, which I didn't find in literature, although I am...
8. I On 'A Quarter Waveplate (QWP) rotated between 2 Polarisers'

While going through the book 'Problems & Solutions in Optics and Photonics' I was having difficulty in understanding a question & have some issues about my own conceptual know-how in this regard. The Question is: A quarter-wave plate is rotated between two crossed polaroids. If an unpolarised...
9. I What is the difference between first and second-order vacuum polarization?

What determines the order of the vacuumpolarisation? I've added 2 Feynman Diagrams for refference. The first one shows the vacuumpolarisation of the lowest order the second shows the vacuumpolarisation of the 2nd order. What is the difference?
10. I Observables on the "3 polarizers experiment"

Observables on the "3 polarizers experiment" Hi guys, I was analyzing the 3 polarizers experiment. This one: (first 2 minutes -> ) Doing the math (https://faculty.csbsju.edu/frioux/polarize/POLAR-sup.pdf) I realized that the process is similar to the Stern-Gerlach' experiment. Using spins...
11. B How does polarisation in nature work?

Why are lights reflecting off horizontal surfaces like the road, water, or snow horizontally polarized? How does the process happen?
12. 3D Cinema Glasses: An Unsolved Personal Experience

Many years ago I went to the cinema to watch Avatar in 3D, and was provided with polarising 3D glasses at the venue. I can't remember if it was my first 3D film that involved polarising projection technology, but it was certainly one of my first. In any case, the 3D effect worked and I got...
13. Rotation and Polarisation of Light using Jones Matrices

Hello there I am having trouble with part b) of this exercise. I can apply the rotation matrix easily enough and get: $$R(-\theta) \vec J= \begin{bmatrix} A\cos\theta + B\sin{\theta}e^{i\delta} \\ -A\sin\theta + B\cos{\theta}e^{i\delta} \end{bmatrix}$$ I decided to convert the exponential...
14. Finding directions of fast axis to cause circular polarisation

The only thing I can think of is that to create a circularly polarized wave the axes of the quarter wave plate will have to be at 45 degrees to the E vector. Only then it can have both components on the slow and fast axis equal. Then the slow axis will cause delay and the resulting vector will...
15. E

Polarisation through a chiral nematic crystal

If light passes into a birefringent material with constant fast and slow directions, ##\hat{x}## and ##\hat{y}##, that are oriented the same way at any point in the crystal, then the electric field is\vec{E}(z,t) = E_0\hat{x}\cos{(\theta_0)}e^{i\omega(t - \frac{n_x}{c}z)} +...
16. Does a material change the direction of polarization of light?

The polarization referes to the direction of the electric field of a light wave which is to be one direction. The unpolarized light interacts with a material in various ways such as reflection, scattering, refraction. and each of which can transform an unpolarized light into a vertically or...
17. Polarization of elliptical fiber modes

If I have three modes in an optical fiber with elliptical facet as shown in the figure, what would be the polarization direction of the modes... what I know that it is linear polarization and could have several configuration.. but what I want really to know that if could be a situation where the...
18. Polarization of light -- Determine the thickness of the crystal

I don't even know where to start with this problem. What kind of slit makes linearly polarized light circularly polarized? The correct answer is d = lambda/(4(n1 - n2)) = 856nm. But how do I get there? Thanks in beforehand!
19. I Entanglement setup that shouldn't allow for the transmission of info

Suppose we produce a polarisation-entangled photon pair ##A_1## and ##A_2##. Then we entangle another pair ##B_1## and ##B_2##. Now suppose that these photons will not interact with anything, sending ##A_1## and ##B_1## to Alice and ##A_2## and ##B_2## to Bob. Alice measures the polarisations...
20. I Mach-Zender-Interferometer with polarizers

I have a question on how exactly polarizing filters would influence interference in a Mach-Zehnder interferometer. To explain, I'll show some configurations and what I would expect to happen - please tell me if I am incorrect anywhere. Here is the standard MZI configuration with no filters and...
21. Trying to Understand the Polarization of light

I want to understand the concept of polarization of light. I would like someone to clarify how I am thinking about it: If light is a transverse wave and it is basically an electric field(E) and magnetic field(B) each oscillating in different directions (axes) which are perpendicular to each...
22. Things to talk about in a Polarization Write-up

Homework Statement I am doing an assignment on Polarization of light. I have conducted experiments to prove that reflected light is at least partially plane-polarized, and to prove that Malus' Law is true. Both my experiments have given good results. I now need to find enough stuff to write...
23. Destructive interference in Unpolarised light

Destructive interference is excellently demonstrated in Young's double slit experiment, where dark regions are formed due the waves being out of phase. However, what really confuses me is that unpolarised light has intensity. Assuming we had perfectly unpolarised light, as in where the...
24. I Double slit with a quarter wave polarizer on one slit

Suppose a linear polarized light wave front is incident on a double slit. What happens if one places a quarter-wave polarizer in front of only one slit in the double slit experiment? Does one obtain the usual inteference fringes? Or the diffraction pattern only? Else?
25. Reversing the Faraday effect to get an induced current

Hi all! I was thinking if it is possible to revert the Faraday effect. If I have a magnetic field, it interacts with EM wave (light) by changing its polarisation. Can I got a variable magnetic field interacting with polarised light so that I can get induced current in a coil? I can understand...
26. Cause of polarisation due to reflection?

Quoting Resnick and Halliday's Fundamentals of Physics (page 912) on polarization by reflection: It is also known that when light is incident at the interface at a particular angle θb, the Brewster angle, the reflected light is completely plane polarized. Why does light get polarized when it...
27. Formal term for cross-polarization effect

Hi everyone, A friend of mine attending university in Japan is trying to write a paper in English discussing the effect that occurs when looking at a screen through polarized sun glasses (i.e. it looks dark or black). She is looking for a formal term that specifically addresses the screen...
28. Calculating permittivity in a constant field

Homework Statement Having a conducting sphere with radius ##R## and charge ##Q##, dielectric is put on it so that a spherical shell with inner radius ##R## and outer radius ##3R## is formed. Calculate: 1. Electric permitivitty ##\epsilon## such that ##E(r), R<r<3R## is constant and there's...
29. Photon absorbtion and conservation

If a (polarized) photon is absorbed by a polarization filter, does its energy go into the filter? I am wondering if that is the case to obey conservation laws. And if it passes, is its original polarisation direction somehow conserved?
30. 2 Polarizers attenuating a light beam

Homework Statement An angle is given between 2 polarizer's (45 degrees), through them light passes (unpolarized than after passing through the first one it polarizes), some of the light its shown on the display. For how much does the angle needs to be increased for the intensity of light to be...
31. Electromagnetic Lagrangian, EoM, Polarisation States

Homework Statement Attached: Homework Equations Euler-Lagrange equations to find the EoM The Attempt at a Solution [/B] Solution attached: I follow, up to where the sum over ##\mu## reduces to sum over ##\mu=i## only, why are there no ##\mu=0## terms? I don't understand at all. Many...
32. How to find the orientation of polarization of a polarizer

If you have a new linear polarizer, how do you find its orientation of polarization? In other words, how do you orient it so it would, let say, polarize light vertically if there is no marking for the 0 degrees angle?
33. Explore Polarized Light: Tilted Polarizer Effects

https://www.dropbox.com/s/t5lv4nlunn35ok8/phy1.PNG?dl=0 https://www.dropbox.com/s/ktc9pj7qmqhejrv/phy2.PNG?dl=0 https://www.dropbox.com/s/qbjz1p1gokvsgj2/Capture3.PNG?dl=0 I googled "polarizer film diagram" and "malu's law" and "polarizer physics" to obtain the pictures in this thread. I...
34. What do polarisation lens block?

Electromagnetic waves are created by a accelerating charge that induces a changing electric field, that induces a changing magnetic field which propagates together through space. The electric and magnetic field are at right angles to each other. Polarisation blocks all but one plane of the...
35. Textbooks for Electromagnetics, Dielectrics, Magnetic field and Polarisation

I am a Graduate student in Electrical Engineering. I have to work on Electromagnetic, Dielectric, Magnetic field and Polarization for my project. But my problem is I do not have a good background in this course. Now, I really need it in graduate level. My question is, can you guys introduce me a...
36. Quantum polarisation probability

Homework Statement I am stuck on the second paragraph but I thought I would add the first paragraph in case some context would help! Homework Equations |A> = cos(theta)|H> + sin(theta)|V> The Attempt at a Solution I am not wholly comfortable with bra-ket notation with the outer product p =...
37. Brewster's law for incident vertically polarised light

Brewster's law on polarisation states that if a unpolarised light is incident at a certain angle of incidence, then part of it gets plane polarised and is reflected. What happens if the incident light itself is vertically polarised for the same brewster's angle and same wavelength of light used...
38. Orthogonal Polarisation in EM waves and Interference

I've been trying to get my head around Polarisation and how it achieves orthogonality. I'm not sure if this should be in Physics or Electrical Engineering Section. (Mods can move this where appropriate) I know that 2 EM wave with linear polarisations where one wave is shifted by π, they would...
39. How to determine the range of sensitivity for a camera sensor?

I am not sure if this is the best place to ask and I will change locations if need be, but I need some guidance on how to choose a proper sensor for my project. I am currently working as part of a team on a polarimetric camera for ocean imaging. The basic premise is that images, from above the...
40. What is causing the reflected beam's s oscillations at Brewster's angle?

Ive been reading about reflections and transmission at Air water surface. I get the idea that at the Brewster's angle dipoles aligned at the surface can not emit p-oscillations in the reflected direction as the dipole is aligned parallel to this direction. What I don't get is that if the...
41. What is the direction of energy transfer in polarised light?

Homework Statement Okay so this is a concept that I've been having a lot of problems with recently. I watched a few youtube vids to clear things up so now I'd like to make sure my notes are right. 1) For normal polarised light, the oscillations of a wave are in one plane only which include the...
42. Polarisation (light on water surface)

Homework Statement A student looks at the sunlight reflected off a puddle of water. She puts a polarising (Polaroid) filter in front of her eye. As she rotates the filter the puddle appears darker then lighter. Explain this observation Homework EquationsThe Attempt at a Solution Here's my...
43. I Quarter-wave plates and Half-wave plates

Hi, I am aware that quater-wave plates create a phase shifts of λ / 4 between the fast and slow transmission axis. My question is what happens if we place two quater-wave plates in series so that there is 0 degrees between the fast transmission axis and how would result change if they where...
44. I Is Polarisation Entanglement Possible in Photon Detection?

If we don't know the polarisation state of a photon before detection is it reasonable to assume that it's in a superposition of all possible states? Thank you if anyone can clarify.
45. Polarisation of Light: Reflection, Critical Angle & Total Internal Reflection

W.k.t light gets polarised when incident from rarer to denser medium.(gets polarised by reflection at a certain angle ie: angle of polarisation) But if the light is sent from a denser medium to rare mediym, will there be any polarisation?? If there is, will it be due to reflection?? And can the...
46. Finding Polarization Components of an Electric Field Vector

I have a vector that represents the electric field at a specific point. How to find the vertical and horizontal polarization components of this vector?
47. A Is there a polarisation of the microwave background

and if so what is it's orientation
48. Polarisation power of cations

Why the cations having electronic structure of ns2 np6 nd10 have more polarisation power on anions than the cations having electronic structure of ns2 np6?
49. Interpretation of polarisation experiment

Consider a fully entangled pair of polarized photons, A and B, fired at two detectors with polarisation filters in front of them. I have to get a little philosophical to understand the way the interpretations of this experiment play out. My knowledge is still very basic but I'm working on it...
50. B Measurement and the creation/loss of information

If we measure, say, the polarisation of a photon, the polarisation state of the photon collapses along the eigenvector of the observable corresponding to the measurement. This may seem as a loss of information of the original polarisation (for it is now collapsed into another value). However...