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Some further thoughts based on some additional reading:
Donald E. Simanek wrote:
Is it an extension of the infamous "rope through the
picket-fence" model some textbooks foist on students as an analogy to
polarization?
Looked at as slits between conductors, I don't think it is an
extension of the "ropes through the picket-fence" model. I don't
think an ideal multislit - open slits separated by opaque strips _
would produce polarization.
The slit model and the picket fence model fail miserably when applied to
the case of a sandwich of three polarizers. The second's axis is at, say,
45 degrees to the first. The third is at 90 degrees to the first. The
picket fence and slit models would predict no light gets through. But it
does get through. Then remove the middle polarizer and then light
doesn't get through. Any model or analogy which can't deal with this case,
a case so easily demonstrated, isn't worth a moment's consideration.
I think this certainly applies to the picket fence model. I never heardI see that no proponent of this (exceptionally?) scholarly debate
of the "slit model" until now. (Perhaps I confused the wire grid with a
multislit in my first posting). But if the "slit model" refers to the
wire grid model, I think this can pass your test as mentioned in my
second posting. (As I mentioned in my second posting, the wire grid
works by division of components, not "sifting" as in the case of the
picket fence -- using Anderson's expressions).
If, by "slit model," you are thinking of polarization by a single slit
made of metal as I described, I think three of these, the outer two
crossed, would let more light through than just the outer two if the
middle one was at an intermediate angle. (I am not sure how close to
100% polarization by one slit is possible in practice). The polarization
of the light of a given wavelength (or narrow range thereof) that barely
gets through a slit narrowed until the light is just barely visible is
definitely polarized with the plane of polarization along the direction
of the slit as observed visually. I am not thinking of "the slit model"
as many of these single slits put together. The direction of the plane
of polarization is 90 degrees different. I have never read about
polarization of visible light by a single slit in any text. I did not
try it with a non-metallic slit, which would probably have been very
difficult to make sufficiently narrow, if not impossible.
...
Hugh Logan