Intensity for circular polarised light through linear polariser

[dalind]

Hi,

does the intensity change when circularly polarised light passes through a linear polariser?
I am thinking of a flow like this: natural light -> vertical linear polariser -> quarter wave plate -> horizontal linear polariser -> intensity?

After the first polariser, the intensity is 50%, the quarter wave plate changes the linear polarisation to circular. But does the horizontal linear polariser decrease the intensity again?

Edit: Another flow would be natural light -> 45° linear polariser -> quarter wave plate -> - 45° linear polariser -> intensity? Since I think the polarisation is not affected by the quarter wave plate if the light is polarised vertically, I think the first flow would result in a complete absorption of the light by the second polariser (Intensity 0), right?

Thank you.

Cheers,
dalind

 

[dauto]

Yes, the second polariser cuts the intensity of the circular light in half.

 

[Meir Achuz]

... and makes it linearly polarized.
A plane polarizer treats circularly polarized light the same as it treats unpolarized light.

 

[dalind]

Okay, thanks. That's what I thought. And this only works for the second flow I described, for the first one the quarter-wave plate would not change the polarization and would therefore practically be useless, right?