Polarization and Polarizers
HTML-код
- Опубликовано: 2 фев 2013
- A few experiments illustrating what a polarizer is, what it does to light, and what happens when you have two polarizers aligned and crossed. Lastly, what happens when a third polarizer is rotated in between two crossed polarizers? We see the result, but the explanation is left for the viewer to ponder.
Наука
wait can -I- explain why? i clicked hoping you would lmao
As you rotate the middle polarizer from vertical to horizontal, the vertical component of the oscillations go from maximum to zero. And hence, when it is at some inclination, it allows some (non-zero intensity) light to pass through. This light has a non-zero horizontal component (as the transmission axis of the middle polarizer is inclined) which is allowed by the closest polarizer to the viewer.
Studying optical microscopy at the moment. This is very handy for understanding how the polarizers work
The middle polarizer plate actually 'twists' the polarized light from the back one by certain degrees of angle. Thus this is the underlying principle of Liquid Crystal (LC) inside a LCD display. There are various kinds of LC : Twisted Nematic (TN), Super Twisted Nematic (STN), etc.
nice demo
No, but I can maybe offer an idea: Maybe the sort-of linear outlook, there being a wave or massless particles that are 'blocked' from 'passing through' to our eyes or from one place to another, could be questioned.
A polarizer somehow alters the state of the light as measured on the other side, opposite the lamp. This can have to do with many things, including the natural character inherent of the material of which the polarizer is made. A second polarizer directly out of phase, as it were, is said to totally block all of the light--essentially.
But can we be sure there does not exist light in some form or state on the other side? After all, we didn't know there were radio waves until we devised an antenna which resonated with the waves and caused a needle to move on a [galvanometer].
Certainly there could be light still to be discovered which does not resonate with our eyes, or with the photo-detector in a video camera for that matter. Certainly discoveries will be made that will shed light, so to speak, on matters in general, as has happened continually over the centuries.
It's not so much about some things like bullets, or rays or whatever, but about fields (I speculate). The lamp, or flashlight or whatever is used, sets up or brings about a field [in space] which can be affected in varied ways by various materials and objects.
Perhaps the eye is similar to an antenna: If it does not resonate when placed in the field, or has insufficient sensitivity, it does not detect anything there; we see nothing. Indeed that does not necessarily mean that nothing is there!
Just putting a few notions out there:)
I'm sort of hoping you would tell me more.
The filters are more like a wall. If you have a ball going forwards and it hits a wall, it stops. Having heard only this, one might naively assume walls always reduce the balls speed. However, we can add a 2nd wall 45 degrees to the 3rd wall, and suddenly the ball will hit both the 2nd and 3rd wall and still have speed despite hitting two walls.
Because 50% of the light gets trough the first polarizer with 0 degree angle from the vertical. then 25% of the light gets trough the middle one (50% of the 50%) with an 45 degree angle from the vertical. And finaly, 12.5% of the total light get trough the last one, with 90 deggre from the vertical (50% of 50% of 50%).
I need to cut film to 45 degrees for a projector film that was burned. How do i do this?
The middle polarizer transforms the wave vectors such that some components are once again rendered parallel to the polarizing filter in the foreground, allowing some light to pass through. At right angles, this transformation does not happen, and no light is able to pass.
when the middle polarizer is placed diagonal, some of the diagonal components from the vertical polarized light of the first polarizer get through, and these diagonal components also have components in the horizontal region, which get polarized through the thrid polarizer, and a faint light of intensity about 1/4th (1/2 x 1/√2 x 1/√2) the initial intensity is seen. Please correct me if I am wrong, and your welcome if this was helpful.
re: "when the middle polarizer is placed diagonal, some of the diagonal components from the vertical polarized light of the first polarizer get through, and these diagonal components also have components in the horizontal region"
No -- The inserted filter *causes* a new transmission angle at 45 deg. This is called "re-radiation" in the RF engineering field. Physicists fail on explaining this phenom.
I know it's described and calculated by Malus Law, what causes as polarized beam to regain a vector component though is blank to me.
re: "what causes as polarized beam to regain a vector component though is blank to me."
It's easy - the middle filter is not just a filter, it's also a "re-radiator" of the light energy, and at the angle it is positioned at. The kicker is, it has to be at some angle BUT not at 90 degrees from the previous filter. It needs some component (cos(theta)) of energy to work with.
as half of the light goes through the first Polarizer only light of one direction reaches the 2nd Polarizer. because it is shifted (ideally 45°), the light, as it goes through, gets two vector compenents, one perpendicular to each of the Polarizers. so basically half of the remaining light is polarized, so that it wouldn't be able to pass the 1st Polarizer, but pass the 3rd.
can u tell us why?
Hello!
Does anyone know where i can find details about the permeability of the sheets, i mean how much light passes throught without the second polarizer and with the second, any links will help me. Thanks
a=Acos²x
where A is the prepolarized light intensity, a is the postpolarized light intensity, x the angle between boht polarizers.
Note that a=A/2 after passing through the first polarizer no matter which direction it is oriented
Jack Smith was here! UwU
Where can I purchase some of this film please?
Amazon has it. Search for "sheet polarizer" and you'll have options.
Thank you. I did try once but what I was sent did nothing at all. I have a very old couple of pieces of polarized film I've had for 35 years, i use them regularly to test for stresses in glass before engraving. I am looking for more for my students.
I know people are using polarizer to block people from seeing there phones but they are able to see it with special glasses. I want to know how I can get that done.
Neither vertical nor horizontal waves are left. What is left is what lies between 1.1 and 1.2. Or, perhaps 1.00000000000001 and 1.000000...001, I mean who knows what between and much is, them, or do they?
What are the name of these light polarizer? I want to buy few of them but I can't find them on online markets.
I think of it as "polaroid" but searching for that usually brings up instant cameras and film. On Amazon it's listed as "Sheet polarizer".
liked your voice
i dont get it. why?
Because it is circular polarization in action.
is this how those eclipse glasses work?
No, eclipse glasses are just aluminized mylar that lets through a small percentage of the light hitting it.
it is a game of absorpton.
Hi, I need help for a Polarizer Film, for 19-inch HP Pavilion w1907 LCD plz
diffraction?
No - re-radiation (of the light energy) by the inserted filter (NOTICE - it was put in between the other two) at a 45 degree angle. This will pass through the last or 3rd and final filter sheet.
From where I can buy this ... I want to show this to students but can't find one
Amazon has them. Search for "sheet polarizer".
Dear Mr. Jeff Regester.... can i have your permission to use your video in my class?
Absolutely. I hope it's useful!
@@JeffRegester thanks a lot
I think I can. Why ? Is it really a big mystery ?
why
DREAM????
No, they do not let through only electric field vibrations in a single direction. Instead, the probability that a photon passes through is proportionate to it's orientation to the filter.
NEXT!
You keep speaking of 'light passing through', as if it is some stuff or things that travel through other things. Is that the way light really works? What is it that is passing through? Maybe this is only how we visualize it. I believe in an induction-field theory of light propagation, and the field stimulates the eye or the camera sensor and so on. The polarizers interfere with the field. It must have to with the nature of the materials from which the polarizers are made. The typical linear, classical-vector model of light does not work. I say we must reconsider the very outlook and mode of reasoning. And we must have a deeper understanding of how light interacts with matter.
It's because of malus law
Mobile lcd am display paper'
It's bells inequality
That's some confusing shit.
Too much audio overload distortion.