Polarization of light

  • #1
I want to understand the concept of polarization of light. I would like someone to clarify how I am thinking about it:

If light is a transverse wave and it is basically an electric field(E) and magnetic field(B) each oscillating in different directions (axes) which are perpendicular to each other say x-axis for E and z-axis for B and the light propagates in the y-axis. Polarization means that that light is filtered by blocking all light except the one travelling in a certain direction.

1) Say for example, that only light that is travelling vertically is allowed, this means that all light travelling horizontally is blocked. Is this right?
2) If light travelling vertically is allowed only, what does this mean for the Electric Field and Magnetic Field. Is one of them blocked? I know that it doesn't make sense to me, because light is made out of both of E and B. Is it the case that when talk about polarization of light then we are talking about the wave itself which means the E and B fields are inside the wave and their directions of oscillation are actual vertical or horizontal directions?
 

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  • #2
PeroK
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Polarization of light clarification of concept

I want to understand the concept of polarization of light. I would like someone to clarify how I am thinking about it:

If light is a transverse wave and it is basically an electric field(E) and magnetic field(B) each oscillating in different directions (axes) which are perpendicular to each other say x-axis for E and z-axis for B and the light propagates in the y-axis. Polarization means that that light is filtered by blocking all light except the one travelling in a certain direction.

1) Say for example, that only light that is travelling vertically is allowed, this means that all light travelling horizontally is blocked. Is this right?
2) If light travelling vertically is allowed only, what does this mean for the Electric Field and Magnetic Field. Is one of them blocked? I know that it doesn't make sense to me, because light is made out of both of E and B. Is it the case that when talk about polarization of light then we are talking about the wave itself which means the E and B fields are inside the wave and their directions of oscillation are actual vertical or horizontal directions?

Polarisation refers to the orientation of the E & B fields. It's not to do with the direction of propagation of the light.

To take an example. If light is travelling in the z-direction, say, then unpolarised light may have E fields in any orientation and corresponding B fields in any orientation (not in the z-direction, of course, for waves in vacuum). If you restrict the light so that the E field must be in the x-direction and hence the B field in the y-direction, then that light is polarised (by convention it is said to be polarised in the x-direction).

That's the case of linear polarisation.
 
  • #3
ZapperZ
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Polarization of light is defined by the orientation of the E-field vector. So if you have it vertically polarized, it means that the E-field is in the vertical direction.

Zz.
 
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Merlin3189
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