# Circularly polarized light of intensity through a polariser (1 Viewer)

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#### Amith2006

Sir,
A circularly polarised light of intensity I is passed through a polariser resulting in the production of plane polarised light.What is the intensity of the plane polarised light? What is the expression which governs this effect?The formula that I know is I' = I cos^2x(Mallus law).Here the symbol ^ represents power.But in this case the angle between the plane of transmission of the analyser and the plane of polariser is not given.Please explain.

#### Claude Bile

What is x in the equation you quoted?

Claude.

#### Meir Achuz

Homework Helper
Gold Member
The result of passing circularly polarized light through a plane polarizer is the same as it would be for originally unpolarized light. The transmitted light is plane polarized wilth half the intensity of the original light. There is no dependence on the angle (I assume it to be your x) until the now plane polarized light passes through a second plane polarizer.

#### Amith2006

Sir,
Can I take that each time a polarised light passes through a polariser its intensity becomes half?Is it also applicable to unpolarised light?

#### Meir Achuz

Homework Helper
Gold Member
"The result of passing circularly polarized light through a plane polarizer is the same as it would be for originally unpolarized light. The transmitted light is plane polarized wilth half the intensity of the original light. "

#### Amith2006

Meir Achuz said:
"The result of passing circularly polarized light through a plane polarizer is the same as it would be for originally unpolarized light. The transmitted light is plane polarized wilth half the intensity of the original light. "
Sir,
Could you please tell me materials which produce plane,circular and elliptically polarised light?

#### Meir Achuz

Homework Helper
Gold Member
There are a number of ways to polarize light.
Land's first invention (before the camera) was "polaroid", a material that only let light plane poloarized in one direction pass through.
Plane polarization can also be produced by scattering off a flat surface at angles close to arctan(n2/n1).
Circular and elliptical polarization can be produced by "optically active" crystals that have different indices of refraction in different directions.
There are other ways that get a bit more complicated.

#### Amith2006

Thank you Sir for clearing my doubt.

#### total chaos

hi ,
i want to know if anybody can point me to some microscopic model which explains why light bends at the interface of 2 media?????? i am not asking for an exact mathematical model (although such a thing would be nice). an well founded physical explanation would be enough for me.

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