Can a wire grid used for polarizing also cause diffraction?

[Dinheiro]

Just wondering, in order to polarize a light beam with a wire grid you could also get some difraction in despite of the wire's length, right? And, if so, will the difracted rays also be polarized?

 

[Drakkith]

Yes, you will get diffracted rays since some of the wavefront is absorbed by the grid. I'm not sure if the diffracted light will also be polarized, but I would think so.

 

[namati]

If the effective space between the wires is more than the wavelength of the light, it will tend diffract. If it's less, it will tend to be polarized.

The wire used to make diffraction gratings is usually flat and aligned to make "slots" (like this: IIIIII) to cause maximum diffraction. The wire in polarizers is usually round to minimize diffraction. Both have a polarizing effect, but a properly selected polarizer will work better for this.