How can transverse waves be polarised?

1 Answer
Oct 29, 2015

Have a look:


Basically you need a conducting grid that can "trap" one component of the electric field of the incoming unpolarized wave. For example:

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The free electron in the metal rod of the grid "uses" the incoming wave #vecE# field to move up and down practically cancelling it (using its energy) as in an antenna. So, the emerging wave will lose all the components of the #vecE# field parallel to the rod.

The case I showed you can be tested using microeaves and a piece of chicken wire (the wavelength of microwaves is comparable with the gap spacing of the mesh).
If you have, say, visible light of smaller wavelength you may use a grid of special polymers called polaroid.