Talk:Polarizer/Lengthy quotes

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Quote from Handbook of Optics Second Edition vol2 22.19, Bass M regarding polarizer VS analyzer and Homogeneous circular polarizers[edit]


There are few good and convenient circularly or elliptically polarizing mechanisms ,
whereas linear polarizers are simple , inexpensive , and of high quality . Therefore , most
circular and elliptical polarizers incorporate linear polarizers to perform the polarizing , and
retarders to convert polarization states . For such compound devices , the distinction
between a polarizer and an analyzer becomes significant . This is perhaps best illustrated
by three examples : (1) a left circular polarizer (which is also a horizontal linear analyzer)
constructed from a horizontal linear polarizer LP (0 8 ) followed by a quarter-wave linear
retarder with the fast axis oriented at 135 8 , QWLR (135 8 ) Eq . 14 , (2) a left circular analyzer
(which is also a horizontal linear polarizer) constructed from a QWLR (45 8 ) followed by an
LP (0 8 ) Eq . 15 , and , (3) a left circular analyzer and polarizer constructed from a
QWLR (135 8 ) , then an LP (0 8 ) , followed by a QWLR (45 8 ) Eq . 16 . The Mueller matrix
equations and exiting polarization states for arbitrary incident states are as follows :

((Matrices didn't copy and paste))<br>

The device in Eq . (14) transmits only left circularly polarized light , because the zeroth and
third elements have equal magnitude and opposite sign , making it a left circular polarizer .
However , the transmitted flux ( s 0  1 s 1 ) / 2 is the flux of horizontal linearly polarized light in
the incident beam , making it a horizontal linear analyzer . Similarly , the transmitted flux
from the example in Eq . (15) , ( s 0  2 s 3 ) / 2 , is the flux of left circularly polarized light in the
incident beam , making this combination a left circular analyzer . The final polarizer makes
the device in Eq . (15) a horizontal linear polarizer , although this is not the standard
Mueller matrix for horizontal linear polarizers found in tables . Thus an analyzer for a state
does not necessarily transmit the state ; its transmitted flux is proportional to the amount
of the analyzed state in the incident beam . Examples in Eqs . (14) and (15) are referred to
as inhomogeneous polarization elements because the eigenpolarizations are not orthogonal
, and the characteristics of the device are different for propagation in opposite
directions . The device in Eq . (16) is both a left circular polarizer and a left circular
analyzer ; it has the same characteristics for propagation in opposite directions , and is
referred to as a homogeneous left circular polarizer .

Dave3 (talk) 15:36, 13 March 2010 (UTC)

Federal Standard 1037C position on handedness [edit]

On their website

Circular polarization: In electromagnetic wave propagation, polarization such that the tip of the electric
field vector describes a helix.
Note 4: Circular polarization may be referred to as "right-hand" or "left-hand," depending on whether
the helix describes the thread of a right-hand or left-hand screw, respectively.
Animation of Right-handed/Clockwise circularly polarized Light as viewed from the receiver.

Note that they don't define clockwise and counter-clockwise and define the handedness by the handedness of the helix. However another way to determine the handedness of a wave its to observe the temporal rotation the field. When one, to determine the handedness this other way, points ones thumb towards the source and matches the temporal rotation with ones fingers, the handedness matches the handedness of the helix. Therefore it is reasonable to look towards the source to determine if it is clockwise or counter-clockwise. When you do this, a right handed wave is clockwise polarized.
Dave3 (talk) 21:04, 17 March 2010 (UTC)

Regarding the Fed Stand 1037C[edit]

First, unfortunately, the link you have is not working. Below, I have linked the correct page with my response. Perhaps I did not read Fed Stand 1037C on polarization closely enough, but I did not see any emphasis on screw threads. The right-handed, left-handed terminology in Chirality is used by the engineering community, and is an accepted convention - in engineering. In addition, the text of the referenced book agrees with the Fed Stand 1037C explicit definition of Polarization. I have copy and pasted that text, verbatim, below. Thanks for your interest in this article. Feel free to expand it, if you wish. ----Steve Quinn (talk) 15:13, 28 June 2010 (UTC)

HANDBOOK OPTICS Volume I,Devices , Measurements and Properties,Michael Bass Ch5 Section 6 on handedness[edit]

In a footnote it says

Right-circularly polarized light is defined as a clockwise rotation of the electric vector when the observer is looking against the direction the wave is traveling .

Dave3 (talk) 21:04, 17 March 2010 (UTC)

Electromagnetic Waves & Antennas – S. J. Orfanidis Ch2 Sec5 on handedness [edit]

 To decide whether this represents right or left circular polarization, we use the IEEE convention, which is as follows.
Curl the fingers of your left and right hands into a fist and point both thumbs towards the direction of propagation.
 If the fingers of your right (left) hand are curling in the direction of rotation of the electric field, then the
 polarization is right (left) polarized.†
Footnote reads:
†Most engineering texts use the IEEE convention and most physics texts, the opposite convention.

Dave3 (talk) 21:04, 17 March 2010 (UTC)

Introduction to Quantum Theory 2ED David Park Sec 2.2 Pg32[edit]

Below is a OCR of an image of the page.

It should be understood at the outset that the polarization of a beam of light is exactly the same kind of thing as the spin of a beam of electrons, the differences of terminology reflecting only the accidents of the historical order of discovery. A photon of circularly polarized light has a spin of one unit of h/2pi directed either parallel or antiparallel to its direction of propagation. An electron has a spin of 1/2(h/2pi) and can have the same two orientations, though, as we shall see in Chap. 6, it can have others as well. Light also has states of linear polarization that can be represented as linear combinations of the circularly polarized states.(Footnote 4) Since linear polarization is easy to visualize and experimentally familiar, we shall discuss this case rather than that of circular polarization.

Footnote 4- Since we shall not need to see how this is done, a reference will suffice: M. V. / Klein, Optics, chap, 10, Wiley, New York, 1970. QC357.2 .K55

This is original image [1]
Dave3457 (talk) 21:33, 30 June 2010 (UTC)

Metamaterials and Plasmonics: Fundamentals, Modelling, Applications By Saïd Zouhdi, Ari Sihvola, Alexey P. Vinogradov [edit]

In the below, the second paragraph in Section 2.1.2 is simply false.
Here is a screen shot of the relevant page
The Federal standard defines handedness of a wave by the handedness of the screw the wave makes in space. Refer Talk:Polarizer/Lengthy_quotes#Federal_Standard_1037C_position_on_handedness

This conforms to the Physicist’s definition (Refer the Wikipedia page on handedness Circular_polarization#In_physics.2C_astronomy.2C_and_optics) But physicists look toward the source not away as is suggested by this book.
Here is the image the quote from the book referred to
He is correct that the wave in the image is right-handed according to the Federal Standard but…contrary to the caption the spiral in the image is not a left-handed spiral. Again the Federal Standard states that the handedness of the helix matches the defined handedness of polarization.
Talk:Polarizer/Lengthy_quotes#Federal Standard 1037C
Dave3 (talk) 21:04, 17 March 2010 (UTC)

Chirality (electromagnetism)[edit]

Thanks for your edit to Chirality (electromagnetism). I don't see where the book contradicts Federal Standard 1037C. I would have to scrutinize the image in the book for a little longer to determine if the image contradicts what the author has said in the book. However, I want to say that you do good work. If you wish to expand this article, feel free. Anyway - below is a quotation from Federal Standard 1037C. I will put this in the article verbatim because it is Public Domain.

Sorry that it took so long to respond to you. You are correct that this subject can be confusing, and I am not really comfortable with "chirality" myself. Anyway: here is the quote. The first word below is linked to the exact page this comes from: ----Steve Quinn (talk) 15:03, 28 June 2010 (UTC)

polarization: "Of an electromagnetic wave, the property that describes the orientation, i.e., time-varying direction and amplitude, of the electric field vector. (188) Note 1: States of polarization are described in terms of the figures traced as a function of time by the projection of the extremity of a representation of the electric vector onto a fixed plane in space, which plane is perpendicular to the direction of propagation. In general, the figure, i.e., polarization, is elliptical and is traced in a clockwise or counterclockwise sense, as viewed in the direction of propagation. If the major and minor axes of the ellipse are equal, the polarization is said to be circular . If the minor axis of the ellipse is zero, the polarization is said to be linear . Rotation of the electric vector in a clockwise sense is designated right-hand polarization , and rotation in a counterclockwise sense is designated left-hand polarization . Note 2: Mathematically, an elliptically polarized wave may be described as the vector sum of two waves of equal wavelength but unequal amplitude, and in quadrature (having their respective electric vectors at right angles and /2 radians out of phase)."

Thanks for the compliment.
Are you sure that the quote came from the Federal Standard Website because it contradicts a statement they make somewhere else. Quote: “Note 4: Circular polarization may be referred to as "right-hand" or "left-hand," depending on whether the helix describes the thread of a right-hand or left-hand screw, respectively.” [2] The “Note 4” quote I just cited matches the “physics” definition, while the quote you just cited matches the “engineering” definition. Go to Circular_polarization#Left.2Fright_handedness_conventions to convince yourself of this. (I fixed the dead link, thanks. I will be checking some other links to the same page.)
I could not confirm the source of your quote as the link did not go to the exact page, nor could I find the source by Googling a sentence fragment of it.
Like you, I have “chirality” issues myself and it took me quite a while to sort things out but I, at least at this time, am considering the Wikipedia section I just cited to be the final authority on the matter.
Your quote is a good one but where did it come from? If it came from an IEEE page that would be great and I would included it as a reference myself in the Wikipedia article on handedness. If it did in fact come from Federal Standards, we are in big trouble.
I rechecked my criticism of the book and I still feel that I am right. To keep things organized I expanded my comment in the actual section Talk:Polarizer/Lengthy_quotes#Metamaterials_and_Plasmonics:_Fundamentals.2C_Modelling.2C_Applications_By_Sa.C3.AFd_Zouhdi.2C_Ari_Sihvola.2C_Alexey_P._Vinogradov
Later Dave3457 (talk) 18:38, 29 June 2010 (UTC)
Apparently, for the first link to polarization, which I had above, it is neccessary to to click on A - Z at the bottom, then select the appropriate letter on the right. In this case the appropriate letter would be "P", and then scroll down to polarization. But, now, you don't have to do all that. This is because, I clicked on your link for circular polarization and from there was able to click on polarization and got a more accurate URL. Here is the link for polarization...LINK.
First, I am wondering how did you come up with that accurate URL. To be able to do this would come in handy, rather than expecting someone to go through looking up a term alphabetically.----Steve Quinn (talk) 02:01, 1 July 2010 (UTC)
After linking to (your link) circular polarization in Federal Standard 1037C, I see what you are getting at with the following: "right-hand" or "left-hand," depending on whether the helix describes the thread of a right-hand or left-hand screw, respectively. At first I didn't know how you obtained this description, as you did not understand how I obtained my description. So now we have two descriptions - polarization, and circular polarization. We can study both and see what the agreement and differences are between them. And I believe I came across a third description at FS-1037C: elliptical polarization. Below is the 1037C definition:
In electromagnetic wave propagation, polarization such that the tip of the electric field vector describes an ellipse in any fixed plane intersecting, and normal to, the direction of propagation. (188) Note 1: An elliptically polarized wave may be resolved into two linearly polarized waves in phase quadrature with their polarization planes at right angles to each other. [2196] Note 2: Circular and linear polarization are special cases of elliptical polarization. ----Steve Quinn (talk) 02:26, 1 July 2010 (UTC)
To find this I clicked on "Index" at the bottom of this page, which brings up APPENDIX B ABBREVIATED INDEX. At the bottom of this list is the word "wave". I clicked on "wave" which generated another list. On this list I was able to click on "elliptical polarization", which is the ninth term down on the list. ----Steve Quinn (talk) 02:33, 1 July 2010 (UTC)
In the article, Chirality (electromagnetism) you might be interested to notice that I previously added two of your images (a few days ago). Also take a look at Reference # 3 - It reads: Note: For more discussion regarding wave propagation and handedness see: Talk:Polarizer/Lengthy_quotes#Metamaterials and Plasmonics. I was thinking that what you have on this page would be interesting to those who venture to this article. I might simply change the link to the top of this page, since the other stuff is interesting as well. ----Steve Quinn (talk) 03:07, 1 July 2010 (UTC)
I’m guessing I was able to get a direct link because I avoided the index page. That page, I’m assuming, is using java and that’s the reason its URL doesn’t change. I just happened to have used the search page when I found my page. Interestingly the index page doesn’t have a link to the search page, I found the link on the home page.
Well the two definitions definitely contradict one another. I was able to find an email address and have composed and sent Bill Ingram an email. I have pasted it below in a separate section.#Email_to_Federal_Standards_website We’ll see what happens.
The Federal standards section on “elliptical polarization” seems kosher to me.
I do have some feedback regarding your new section “Wave propagation as handedness”. Assuming you’re interested in it I will comment later after I deal with this handedness issue. Dave3457 (talk) 23:46, 1 July 2010 (UTC)

Email to Federal Standards website[edit]

Subject: There is a contradiction on your Federal Standard 1037C website.

In case this email address is indeed active and you read but dismissed the email sent a few months ago I posted the following on Wikipedia’s Circular polarization page. The fact that it is still there in spite of peer review should be evidence that the contradiction is a reality.

The Wikipedia note reads...

“At present The Institute for Telecommunication Sciences (ITS), the United States federal agency which proposes standards, is proposing two contradictory conventions of handedness.”

A version of the original email is below.
The Wikipedia editors have found a contradiction on your website ( ) regarding the handedness of circularly polarized waves.

On this page ( ) it reads...

"Note 1. ... In general, the figure, i.e., polarization, is elliptical and is traced in a clockwise or counterclockwise sense, as viewed in the direction of propagation. ... Rotation of the electric vector in a clockwise sense is designated right-hand polarization , and rotation in a counterclockwise sense is designated left-hand polarization . "

The above is the same as the IEEE convention which states..

."the sense of polarization, or handedness ... is called right handed (left handed) if the direction of rotation is clockwise (counterclockwise) for an observer looking in the direction of propagation"

However on this page ( ) it says....

"Note 4: Circular polarization may be referred to as "right-hand" or "left-hand," depending on whether the helix describes the thread of a right-hand or left-hand screw, respectively."

The above is only true if one is using the opposite convention.

As things can be confusing I would refer you to the Wikipedia section ( ) which has animations of both left and right handed polarized waves and discusses these two conventions in detail.

Please get back to me if any action is taken to resolve this contradiction so that I can update Wikipedia.

Dave3457 (talk) 17:01, 19 January 2011 (UTC)

Response Email from Federal Standards website

Thank you for the information.

We are not updating 1037C any more and the definitions on the web page are available for archival purposes only. Fifteen years ago, when we wrote those definitions, there was no other on-line resource to address the issues. Nowadays we have places like Wikipedia that do a good job at defining the principles.

I am not personally familiar enough with right- and left-polarization to conclude which website is correct on the matter.

I'm sorry we couldn't be of more help,
-- William
Dave3457 (talk) 03:10, 23 January 2011 (UTC)