[hamdani yusuf (OP)]

In Wikipedia article, reflective polarizer is called beam-splitting polarizer.

Linear polarizers can be divided into two general categories: absorptive polarizers, where the unwanted polarization states are absorbed by the device, and beam-splitting polarizers, where the unpolarized beam is split into two beams with opposite polarization states.

https://en.m.wikipedia.org/wiki/Polarizer

[hamdani yusuf (OP)]

This demonstration of polarization rotation by polarizer should be enough to explain and demistify what's so called three polarizers paradox.

[hamdani yusuf (OP)]

three polarizers paradox.

[hamdani yusuf (OP)]

I've recorded a video showing behavior of absorptive polarizer in visible light.

Here it is.

[Origin]

three polarizers paradox.

It's not really a paradox.

[hamdani yusuf (OP)]

three polarizers paradox.

It's not really a paradox.

A paradox is a logically self-contradictory statement or a statement that runs contrary to one's expectation.

There are someone clearly expected different results, otherwise they won't call it weirdweird, creepy, or counterintuitive.

[hamdani yusuf (OP)]

He suggests near the end of the video, calling the polarizer filter may lead people to expect different results.

[hamdani yusuf (OP)]

I just got an even stronger evidence that diffracted light is produced by the edges of the obstacle, instead of the space between those edges. The experiment involves linear polarization.

I've finally uploaded the video.

In a previous video from my other thread, the edges of polarizers are used to produce diffraction pattern. From the results, we can cross-check our current model on how light interacts with matter.

[Origin]

A paradox is a logically self-contradictory statement or a statement that runs contrary to one's expectation.

Correct and it is not logically self-contradictory to have light show through when a polarizer is at 45 deg between two polarizers at 90 deg to each other.  You get exactly what is expected if you have any knowledge about quantum physics.
A boat that is made out of steel is not a paradox if you understand buoyancy even though steel sinks.

[Bored chemist]

For what it's worth, the classical description of polarisation also explains the transmission through three polarisers.

It's not a very paradoxical paradox.

[hamdani yusuf (OP)]

For what it's worth, the classical description of polarisation also explains the transmission through three polarisers.

It's not a very paradoxical paradox.

I agree. The article below explains how it's explained classically, and identifies the cause of confusions.

http://alienryderflex.com/polarizer/
Third-Polarizing-Filter Experiment Demystified ? How It Works

Spookiness and the Word ?Filter?

Why do these results seem spooky? The reason is because of the misapplication of the word ?filter.? A filter is commonly understood to mean a device that knocks some items out of a stream, while leaving others essentially untouched. A good example of a filter is a sieve ? it blocks objects of a particular size, while allowing objects of other sizes to pass through.


Understood this way, the results of the polarizer experiment are indeed spooky. If the all-blocking equivalent of Figure 2 is constructed using sieves or color frequency filters (see Figures 4 and 5), we are certainly confident that the addition of more filters in the middle of the sequence will not yield different results at the end.

But what if our so-called ?filters? could not only block components of the stream, but also change them? Then we would not be surprised at all if the addition of new ?filters? in the middle caused items to get through to the end. If a sieve could not only block particles, but also change their size, or if a color filter could not only block frequencies, but shift light to a different frequency, then all bets are off.

[hamdani yusuf (OP)]

In my other thread on microwave transmission, I've shown some effects of polarization which have similarities with the effects in visible light spectrum. But I haven't found the analogue of conjoined twin polarizer.

Here is another video investigating the effect of twin polarizer.

It shows the effect of double polarizer when they are close to each other but are still separated electrically. The last part shows the polarisation of microwave coming out from the last polarizer.

The next video will show the effect of double polarizer when they are close to each other and electrically connected, so stay tuned.

And here are videos demonstrating conjoined twin polarizer

In the end of the experiment, it's shown that rotating the receiver can make the reading down to 0, which means that the microwave is linearly polarized instead of eliptical or circularly polarized.

[hamdani yusuf (OP)]

Light Interference versus Polarization

In this demonstration, a Michelson-Morley Interferometer is used to create an interference pattern between a beam of light with itself.  This interference seems to be abolished when one ray's polarization is rotated by 90 degrees.

This video can save me money, time and effort to demistify experimental results with light.

[hamdani yusuf (OP)]

You can find good visualizations in this video to explain polarization.

Lecture -- Electromagnetic Wave Polarization

This video covers electromagnetic wave polarization. The material presented is consistent with the definitions and conventions defined by The Institute of Electrical and Electronics Engineers (IEEE). Definitions are presented. Linear, circular, and elliptical polarizations are explained and visualized using high-quality graphics. Righthand circular polarization (RCP) and lefthand circular polarization (LCP) are defined and visualized. The Poincare sphere is presented as a graphical way to represent polarizations. A polarization explicit form for the mathematical expression of a plane wave is given as an easy way to identify the polarization of a wave given its expression.

[hamdani yusuf (OP)]

This is another interesting video to demonstrate polarization of light, and its interaction with a metal mirror.

How Light's Polarization Can Change After Reflecting from a Metal Mirror | Thorlabs Insights

Metallic mirrors are frequently used to steer light through optical setups. The beam?s direction and shape are typically monitored and optimized after mirror reflection, but reflection-induced changes to the beam?s polarization state are often not considered. Disregarding these changes is reasonable if the application is not polarization-dependent, but it can lead to unexpected results if the application is sensitive to polarization.

Reflection from a metallic surface can change light?s polarization state because metals have complex refractive indices, which are different for P- and S-polarized light. When light is purely S- or P-polarized, incident and reflected polarization states are the same. However, linearly polarized light that is a combination of S- and P-polarized light will usually be reflected as elliptically polarized light. A further complication to consider is that the polarization state of the incident light can be changed by just tilting the mirror, since the polarization state is based on the plane of incidence.

In this demonstration, we explore these concepts and show what to expect when different linear polarization states reflect from a protected silver mirror oriented at a 45? angle. The polarization state of the incident light is determined using measurements taken with a polarimeter constructed from a quarter-wave plate, linear polarizer, and power sensor. Our Stokes parameter calculations take into account the wave plate?s actual retardance, which improves accuracy. The polarization state of the reflected light is measured using a turnkey polarimeter, whose polarization ellipse display is used to visualize the dynamic polarization changes that occur as the incident linear polarization state rotates between S- and P-polarized light.

00:00 Introduction
01:13 Polarization After Reflection
03:31 Input Beam Setup Overview
04:14 DIY Polarimeter Overview
04:52 Measure QWP Retardance
7:15 Measure Stokes Parameters
8:25 Reflection of P-Polarized Input
9:34 Reflection of S-Polarized Input
11:04 Other Linearly Polarized Inputs

[hamdani yusuf (OP)]

Reflection from a metallic surface can change light?s polarization state because metals have complex refractive indices, which are different for P- and S-polarized light. When light is purely S- or P-polarized, incident and reflected polarization states are the same. However, linearly polarized light that is a combination of S- and P-polarized light will usually be reflected as elliptically polarized light.

Linear polarization is the simplest case of polarization. It's a special case of elliptical polarization, where the eccentricity is 1. Another special case is circular polarization, where the eccentricity is 0.

In this case, the oscillation in y axis has the same frequency as the oscillation in x axis. We can think of even more general cases where they are different, such as Lissajous curves.




This can be done using FM antenna like in the picture below.

https://en.m.wikipedia.org/wiki/Circular_polarization

[hamdani yusuf (OP)]

Another way to generalize the oscillation is as cyclocycloid.

A cyclocycloid is a roulette traced by a point attached to a circle of radius r rolling around, a fixed circle of radius R, where the point is at a distance d from the center of the exterior circle
https://en.m.wikipedia.org/wiki/Cyclocycloid

[hamdani yusuf (OP)]

Not Everyone Can See Haidinger's Brush?Can You?

I show you how some people can see the direction of polarized light and show you how to see it.

[hamdani yusuf (OP)]

Create Circularly Polarized Light Using a Quarter-Wave Plate (QWP) | Thorlabs Insights

Circularly polarized light can be generated by placing a quarter-wave plate in a linearly polarized beam, provided a couple of conditions are met. The first is that the light's wavelength falls within the wave plate's operating range. The second is that the wave plate's slow and fast axes, which are orthogonal, are oriented at 45? to the direction of the linear polarization state. When this is true, the incident light has equal-magnitude components parallel to the wave plate's two axes. The wave plate delays the component parallel to the slow axis by a quarter of the light's wavelength (pi/2) with respect to the component parallel to the fast axis. By creating this delay, the wave plate converts the polarization state from linear to circular.

An animation at the beginning of the demonstration illustrates the results of aligning the input linear polarization state with the wave plate's fast axis, slow axis, and angles in between. The perspective used to describe the angles and orientations is looking into the source, opposite the direction of light propagation. The procedure is then demonstrated for orienting input and output polarizers to define the reference orthogonal polarization directions, as well as provide polarization-dependent power measurements. The wave plate is placed between the two polarizers, and the effects of different orientations are explored. The quality of the circularly polarized light output by the wave plate is checked by rotating the second polarizer's transmission axis. The light's polarization is closer to circular when the power reading fluctuates less during rotation.

0:00 - Introduction
0:43 - QWP Use Discussed, Illustrated
3:24 - Step 1: Cross Linear Polarizers
5:19 - Step 2: Align QWP
8:40 - Step 3: Circular Polarization Check

[hamdani yusuf (OP)]

Another way to generalize the oscillation is as cyclocycloid.

I asked chatGPT about it.

Cyclocycloid polarization is not a standard term in physics or optics, and it does not appear to describe any established scientific concept. It might be a term from a niche field, a hypothetical idea, or a misinterpretation of an existing concept.

If you are referring to a type of polarization (the orientation of the oscillations of light waves or other electromagnetic waves), it might relate to a specific geometric or dynamic pattern of polarization that resembles a cycloid, which is the curve traced by a point on the rim of a circular wheel as it rolls along a straight line.

Here are possible interpretations:

1. Cycloid-shaped polarization pattern: It could describe a light wave whose polarization vector traces a cycloid shape as the wave propagates.


2. Rotational or compound polarization dynamics: If it?s a combination of different types of polarization (e.g., linear and circular), the term could refer to a complex trajectory of the polarization vector.



Could you clarify the context in which you encountered this term? It might help in providing a more accurate explanation.

The same question for Gemini.

Cyclocycloid polarization is a complex phenomenon observed in some magnetic materials, particularly multiferroics. It involves the interplay of two distinct cycloidal spin orders, leading to unique magnetic and electrical properties.
https://en.m.wikipedia.org/wiki/Multiferroics?hl=en-US
Key features of cyclocycloid polarization:
 * Two cycloidal spin orders: The material exhibits two distinct cycloidal spin orders, each with its own propagation vector and polarization direction.
 * Phase coexistence: The two cycloidal orders coexist within the material, often forming a complex pattern of domains.
 * Magnetically tunable polarization: The direction and magnitude of the electric polarization can be controlled by applying a magnetic field.
 * Emergent phenomena: The interplay of the two cycloidal orders can lead to emergent phenomena, such as the formation of skyrmions and topological spin textures.
Origin of cyclocycloid polarization:
The exact mechanism behind cyclocycloid polarization is still under investigation, but it is believed to arise from the strong coupling between the magnetic and electric order parameters in multiferroic materials. The two cycloidal spin orders may interact through exchange interactions or magnetoelectric coupling, leading to the formation of the complex polarization pattern.
Significance of cyclocycloid polarization:
Cyclocycloid polarization is a fascinating phenomenon with potential implications for future technologies. The ability to control electric polarization with magnetic fields could lead to new types of magnetoelectric devices, such as sensors, actuators, and memory devices. Additionally, the emergent phenomena associated with cyclocycloid polarization may offer insights into fundamental physics, such as the behavior of topological spin textures.
Further research:
Further research is needed to fully understand the underlying mechanisms of cyclocycloid polarization and to explore its potential applications. This includes developing new experimental techniques to probe the microscopic structure of these materials and theoretical models to explain their complex behavior.