Intro to Polarization Filters! or...why are those sunglasses so expensive?

Intro to Polarization Filters! or...why are those sunglasses so expensive? | Doc Physics

Рет қаралды 136,653

11 жыл бұрын

We figure out why light waves that are shaking a certain direction can make it through polarization filters while others can't. We also hint at the Law of Malus and more beautiful Polaroid filter combinations.

Пікірлер: 196

@08levyr 10 жыл бұрын

FINALLY SOME ONE WHO CAN ACTUALLY EXPLAIN PHYSICS WITHOUT MAKING IT BORING! Physics is probably the most interesting subject - yet every where I look people have managed to make it such an unfriendly topic! Thank you so much :D

@DocSchuster 10 жыл бұрын

You are quite welcome. I love physics, too!

@skotiskiller 9 жыл бұрын

Well done brother.I am Physics student and i had a project in polarization weeks ago and you refreshed my knowledge there.

@Connect63 9 жыл бұрын

Hands down the best demonstration I've seen on this topic. Thank you :)

@apoorva3062 9 жыл бұрын

Those experiments were AMAZING!!! Funny how we could see through!!

@DocSchuster 10 жыл бұрын

I'm dodgy because I'm not an expert. You'll want an engineer for that question, since I believe it is a standard analysis technique for stress and strain in materials. I'd love to hear what you learn! Thanks for watching!

@DocSchuster 11 жыл бұрын

Those are great ideas. I'll put them on my short list! Thanks for your interest.

@zyadbama 10 жыл бұрын

Absolutely amazing! Keep up the good work!

@msSnilloc 9 жыл бұрын

This is hilarious and so helpful. Thanks a million :D

@dipanshu9647 9 жыл бұрын

Doc you r awsm buddy. Best physics instructor

@giorgixyz1909 3 жыл бұрын

your excitement is so passionate I love it

@apotter8888 4 жыл бұрын

Thank you. I have been reading and watching many videos on this, and finally YOURS explains it! :)

@DocSchuster 9 жыл бұрын

Mariam - I am sorry to confuse you! I elected to only draw and discuss the electric field. But you are correct. The magnetic field is destroyed simultaneously when the electric field is. The light as a whole is absorbed.

@prwexler 9 жыл бұрын

There was a day when polarized lenses were GREAT, and then came the era of LCD screens. I got real tired of twisting my neck this way or that to be able to see what was on an LCD screen. My scrip is so ugly that it takes much effort, these days, to actually find a place that can make me sunglasses without that polarizing stuff being included.

@Rose1997011 9 жыл бұрын

THANK YOU... I have another question. What if we replace that polarising filter with a metal ( like iron ) grill, then will the metal grill get itself magnitised by the effect of the electric field or will the WHOLE light gets kinda absorbed and dies eventually and so does the magnetic field? ... where does the magnetic field go? I watched the "Polarisation video" like more than once , it makes perfect sense to talk about the electric, but then why doesn't the magnetic field show any effect in this case ?

@DocSchuster 9 жыл бұрын

I'll have to defer to someone who knows more about polarization of light. That's an interesting question.

@nileshgajwani2431 8 жыл бұрын

+Live Free The electric field energy excites the electrons of the material you are using. The electrons then de-excite and give out light in a plane perpendicular to the plane of polarization

@PariTawale 7 жыл бұрын

but, don't the two fields give rise to each other? if the magnetic field is gone, how is there an electric field?

@abhigyanutsav9651 7 жыл бұрын

I really love the way you explained it.You sir are a great teacher.

@TheBigBawsss 10 жыл бұрын

Doc you are the boss !!! All teachers/lecturers should be like you to make this world a better place. With lecturers like you around everybody could easily become a quantum physicist. In short ,we desperately need to clone you !!!

@BrownMartian 8 жыл бұрын

I got a crystal clear idea of polarization of light. Thank you so much ^_^

@cameronroffey9666 7 жыл бұрын

Honestly you made this so much easier to understand! Thanks so much!

@shafiruki6218 Жыл бұрын

You are so quick, very nice doc master physics

@rachelgringols8664 9 жыл бұрын

Wow! A very cool video! I have an exam on polarization tomorrow, this video really helped, thanks! P.s loveee your enthusiasem

@pokerater4463 8 жыл бұрын

Sir that was an awesome video u made.............thnkx

@Blink23c 10 жыл бұрын

just an enormous thank you!! really helpful!

@DocSchuster 11 жыл бұрын

Yes! Thank you.

@DocSchuster 10 жыл бұрын

THANK YOU!

@sunke88 11 жыл бұрын

Omg. that was the first time I ever said "That was AWESOME" and smiled while learning smtg about physics. you sir, gave me all the motivation I need to do well on my exams. Thank you.

@KamilKaraali 6 жыл бұрын

Great video ..Awesome explanation. Thanks!!!!!!

@DocSchuster 11 жыл бұрын

Thanks. That's consistent with what wrobert3 writes, but is it simply absorption and isotropic re-emission of the light or is it turning into heat. I'm no chemist.

@jondoe7582 11 жыл бұрын

Excellent videos. Keep up the good work!

@Equanimous1998 9 жыл бұрын

Thanks. Lucid explanation.

@LamirLakantry 8 жыл бұрын

Your enthusiasm is infectious. XD Thanks for the video. By the way. The light waves has a hight, right? What scale are we talking? And does it vary?

@shantanusingh2260 10 жыл бұрын

its really a great way to make that stuff easy..........thanks a lot.

@manaspawar8569 8 жыл бұрын

Schuster thnks and keep uploading videos like that

@DocSchuster 11 жыл бұрын

Yes! So there is some sort of "molecular friction" along the molecule's long axis that converts the oscillating E field to heat? Thank you - I was hoping to understand that! I usually model this in class with the slats on a baby crib. Thanks for enriching me.

@SANTOSHKUMAR-pv6fs 4 жыл бұрын

This is the best video on this very topic I like it more than any one

@hongj.1467 3 жыл бұрын

doc you are so close to answering my lab question for me

@67KONKON 4 жыл бұрын

awesome explanation! Thanks :)

@jayeshmahajan28 9 жыл бұрын

really good video!!! would you please help by making a video on polarisation of sun glasses

@evanbohn 11 жыл бұрын

brilliant vid!

@mechikaboombayah4960 6 жыл бұрын

That was Terrific Loved it Doc Newton's cool tho😂😂

@UnfilteredCactus 4 жыл бұрын

Finally! I don't get why all these darn "physicists" don't just explain things clearly like in this video. Thank you!

@ZeroXAlAttas 10 жыл бұрын

i love you man! you remind me of Dory in finding nemo!

@sphericalwave 9 жыл бұрын

Helpful. Thanks!

@phamhatrang8652 7 жыл бұрын

You are completely amazing

@shafiruki6218 Жыл бұрын

Ooh!! It's a nice teach Mr doc phys 😘

@whatcoloristhematrix2209 5 жыл бұрын

Off the wall inquiry, is there a way to view wifi or wave lengths through some form of Polarized optic?

@prakashvasan2334 11 жыл бұрын

man u r tooo good pls upload some more videos! i have a question why light has magnetic field and if it has the light should travel more towards magnet right?

@anusheeltiwari 7 жыл бұрын

This video is great. I know i can always count on him.

@DocSchuster 11 жыл бұрын

Actually, magnetic fields pass through each other completely undeflected. May I recommend my videos on wave interference?

@DocSchuster 11 жыл бұрын

See, I used to feel that way, also. But can we view them as transforming INTO each other if they both reach maxima at the same time and location, then both reach zero together at a later time, etc? Both oscillating, to be sure. Transforming? I am no longer sure.

@thomasalterman 10 жыл бұрын

Great video!

@ryanchan6101 10 жыл бұрын

SQUURRRR

@Joker1531993 5 жыл бұрын

can be used CPL filter like not so good but some protection camera vs lasers ? :)

@samuelpadilla911 10 жыл бұрын

I love this guy

@DocSchuster 11 жыл бұрын

Alternation is a very common mistake. I also thought they alternated once, but they don't. There is an oscillation, so at any given time, the wave is either E and M (normal to each other) or NOTHING AT ALL. The same argument applies for various locations in space for a continuous traveling wave. So you can only block both or none. There is no try.

@wrobert3 11 жыл бұрын

Hi, Thanks great video! Just a note. The molecules in the filter are parallel to the E-field when the light gets absorbed and perpendicular when they are transmitted. The parallel electric field can do work and move the electrons along the long molecules transferring energy (resulting in absorption). The transmission axis is at 90 degrees to the long axis of the molecules.

@rajansah3617 8 жыл бұрын

Hi Doc! Can u please help me understanding process of polarization by reflection, scattering and refraction? please!

@Cosme422 11 жыл бұрын

great video, thank you!

@the1234chocolate 10 жыл бұрын

Thank you very much ! You make my life easier. :))))

@Rose1997011 9 жыл бұрын

GREAT VIDEO .....such an inspiration !! I wish you were my tutor in the other side of the world ! I only find myself confused about the diagram you drew of the electric field WITHOUT the magnetic field ...In EM Waves video , you have mentioned that electric fields cannot exist without a magnetic field ...so why did you just cancel it it it were to exist and have an effect ?

@DocSchuster 11 жыл бұрын

Ooh, good thought. Light requires the relationship E = cB, so Maxwell's equations will guarantee that B is decreased proportionally to E. I can't quite motivate why though...anyone else know a good reason?

@adamlunnon 10 жыл бұрын

Our teachers decided not too teach us anything on this even though it's a large part of my as levels, thanks for explaining it.

@shafiruki6218 Жыл бұрын

Nice tutors😁

@bangnikabang6501 3 жыл бұрын

thank you, very helpful

@reamream9771 8 жыл бұрын

thank you very much :)

@sunshede8070 4 жыл бұрын

Thank you so much!

@Vlican 10 жыл бұрын

thanks Doc

@wreckageyears7815 9 жыл бұрын

This will help my photography :-)

@DocSchuster 11 жыл бұрын

Alright! Get 'em!

@arwa2771 4 жыл бұрын

omg, thank you very much you saved my life because I have a test tomorrow thank you.

@jeffbrouillette4585 7 жыл бұрын

cool stuff...is it possible to isolate or amplify only the magnetic wave

@DocSchuster 7 жыл бұрын

No: E = cB is necessary for light to exist, and it comes from Maxwell's wave equations.

@nhatanhdang2786 5 жыл бұрын

Wow. Just wow.

@11RIHAM 10 жыл бұрын

Sir, you are Awesome!

@DocSchuster 10 жыл бұрын

Thanks, Rham! I think you're great, too!

@srikanthsrnvs123 10 жыл бұрын

Doc Schuster lmao coolest teacher ever :)

@Cosme422 11 жыл бұрын

I'm not a physics guy but the way I see it... the middle filter picks up light at a certain angle from the bottom one, which makes the one on top see it at this new angle that the middle one is outputting at. Like standing 10 feet away from your bedroom door in the hall where you cannot see inside your bedroom. The someone holds a mirror in front of the open door pointing it between the room and you down the hall. Now you can see inside the bedroom. Turn mirror slightly and you see less in there

@DocSchuster 11 жыл бұрын

Fun question! Since E =cB always for light, when E decreases, B also does proportionally. Targeting one or the other would be impossible, as far as I can tell! Short-sighted physicists are always getting in trouble by saying things are impossible, but I'll risk it.

@DocSchuster 11 жыл бұрын

Surprising, to say the least. It naturally falls out of the vector decomposition, but it makes you think about stuff differently. Did they tell you that you can sail into the wind, also? Think about your question as you begin to study quantum physics, too. The middle filter can be seen as an "observer."

@DocSchuster 11 жыл бұрын

I think so. Or put it like this: The only E field that can make it through a polarization filter is the component of the original field that is parallel to the axis of the filter. If a subsequent filter is pi/2 from the first one, it will not allow ANY light from the original filter to pass. Cool. However, since light from, e.g., an incandescent is unpolarized, when it reaches through a p-filter, exactly half makes it through. Ready for the lab?

@mm-zc9no 5 жыл бұрын

you're just so great

@rahulpawaskar8133 8 жыл бұрын

HEY THANK YOU...... I ENJOYED THE VIDEO GOOD......

@omorkhan3437 4 жыл бұрын

why can i see the object when it was placed between the the filters??can someone explain please??

@meetjobanputra5476 10 жыл бұрын

good job

@tornikeonoprishvili5069 6 жыл бұрын

The best!

@CatsStareAtWindmills 11 жыл бұрын

6:04 wowooowowowoow "That's some beautiful physics"

@dylanneal8131 11 жыл бұрын

so does this mean that to block out all light, the magnetic and electric fields must be at right angles to two different filters?

@backtoeden853 3 жыл бұрын

Isnt the plastic slowing down the electromagnetic wave, and thereby the frequency ?

@3risa3 10 жыл бұрын

First off, this is an amazing video, congrats on making it! Secondly, I wish you would have been a tad more blatantly explicit when explaining how putting certain materials between two polarizers creates the colors. What determines the colors you see in the material?

@mohamedabukrawi2094 Жыл бұрын

Perfect

@suunymoon2010 11 жыл бұрын

Out of curiousity, how to tell that it is the E field got blocked and not the H field got blocked ? thx

@Adhish_Rele 8 жыл бұрын

After the introduction of the 1st polarizer what happens to the magnetic field? Does it get absorbed or it passes through with the electric field.

@DocSchuster 8 жыл бұрын

+Adhish Rele We know that E = cB for light, so as E is absorbed, so is B.

@MrCarl111 11 жыл бұрын

I can't understant why if we have two polarized filter at a right angle and we put another one between the two at an angle of, let say 45 degres, we will see light back ?

@vidhyapriya4722 4 жыл бұрын

Tqsm sir

@lucyx8299 10 жыл бұрын

Hi, In the video, you said a polarization filter works through molecules lined up that blocks the electric or magnetic field or both depending on its angle. However, how does this block out light? Would't diffraction occur even if the spacing between the organic molecules of the polarization filter were really small? Thank you in advance for all who take the time to answer my question.

@brianbarnholdt3956 10 жыл бұрын

Nice video. Very educational. One thing though... You claim that when the angle between 2 polarization filters differs by 45 degrees, then the light intensity is greater than 50% (5:10). BUT the next video on my search list Rapid Learning: Physical Optics - Polarizing of Light (4:55) proves that the intensity is exactly 50% with Malus' Law, which you yourself mention. Otherwise great work :D

@DocSchuster 10 жыл бұрын

Let's see. We've got I = I_0(cos(theta))^2. If theta is 45 degrees, then squaring that surely does give 1/2. Thanks! I'll fix that.

@LovinBabu 3 жыл бұрын

How does plastics reverse the effect of polarization?

@AnkitSharma-ti6hv 6 жыл бұрын

I lv ur physics

@abrarahmed5648 7 жыл бұрын

is their any possiblility that i can become your assistant DOC ... because of you i got intreast into physics u r AWSMMMM ;) Thnks a TONN

@DocSchuster 7 жыл бұрын

If you speak another language, you could translate one of my videos into that language for me - that would be a big help for others! I'm glad you love physics, too.

@abrarahmed5648 7 жыл бұрын

sure sir ... wish to meet you some day :) #dream

@chinesemman Жыл бұрын

So if I tear out the polarized filter off my monitor and cut how two eye hole like glasses. Technically the light won't pass through the monitor resulting in a blank white screen. And if I get a pair of glasses and cut the shades off and stick Polarized Filter onto it, would I be abled to see the screen, and people without the glasses they would just see a blank screen on the monitor? Is it really true? That would be so cool. Imagine!

@ashfaqpeerzade166 2 жыл бұрын

Tq my angel ❤️

@hibaimran1867 8 жыл бұрын

wow !! that was amazing .. but can you tell what is an analyzer in polarization ?

@DocSchuster 8 жыл бұрын

+hiba imran Get this - a second filter!

@hibaimran1867 8 жыл бұрын

+Doc Schuster the second polarizer ..?

@DocSchuster 8 жыл бұрын

+hiba imran Sure, or the third, or fourth. Picture it like this - If I want to see if light is polarized (and in what direction), I will need another filter and a light sensor.

@hibaimran1867 8 жыл бұрын

+Doc Schuster ok .. thank .that helps

@DocSchuster 11 жыл бұрын

Shoot. Now you're convincing me that both could be equivalently argued to being blocked. Changing H field will exert force on the electrons in those long organic molecules in just the same way as the E field (but at a right angle). So, I think the key is to see light as a necessary simultaneous combination of oscillating E and H fields. They BOTH interact with the nonconservative forces in the organic molecules.