Light passing through polorise filters
Discussion
Below is a very crude diagram of light passing through (H)orizontal, (V)ertical and (D)iagonal polarizing filters.
If the arrow of light does not continue past the filter then all the light is filtered out.
If the line does continue then looking through the combination of filters you would still see some light coming in to your eye at the end.
(1) --->--- H --->
(2) --->--- H --->--- V
(3) --->--- H --->--- D --->
(4) --->--- H --->--- D --->--- V --->
In case (2) the combination of H and V stops all light.
But in case (4) the addition of a D filter allows light to pass through an H and a V filter combination.
Simple question is : what happens to the light when it passes a D filter that allows it to re-gather some vertical components in order that something can pass through the following V filter?
If the arrow of light does not continue past the filter then all the light is filtered out.
If the line does continue then looking through the combination of filters you would still see some light coming in to your eye at the end.
(1) --->--- H --->
(2) --->--- H --->--- V
(3) --->--- H --->--- D --->
(4) --->--- H --->--- D --->--- V --->
In case (2) the combination of H and V stops all light.
But in case (4) the addition of a D filter allows light to pass through an H and a V filter combination.
Simple question is : what happens to the light when it passes a D filter that allows it to re-gather some vertical components in order that something can pass through the following V filter?
Maybe light with a polarisation angle within the acceptance range of the filter gets emitted closer to the centre of polarisation? People like to think of light simply being transmitted (or absorbed) through transparent materials, but the photons are actually being absorbed and re-emitted, it would be logical if they were emitted with a particular polarisation.
This is how it would operate with radio waves anyway, and photons (in some ways) are modelled as electromagnetic waves.
This is how it would operate with radio waves anyway, and photons (in some ways) are modelled as electromagnetic waves.
I saw a vid a while ago that guided the audience through the maths of why the light passed through the filters.
The maths were embedded within quantum mechanics world of explanations, but essentially its about the probability of a photon to pass through the filter.
A vertical polarized beam of light passing through another vertical polarized filter has a 100% probability of passing through.
A vertical polarized beam of light passing through a diagonal polarized filter has a 50% chance of going through. And here is the quantum mechanics part..... even though each photon in the beam has the same properties, it still comes to a probability as to whether any particular photon will pass through the 45% (diagonal) filter or not.
Or more accurately the probability is COS^2(angle) where the angle is the difference in degrees between the filters. In this case 45degrees.
COS^2(45) = 0.5 .... which equates to a 50% probability.
But having sat through a video of how the maths presents the answer I am still at a loss as to what is actually happening around the simple wording of 'probability'.
Polarized light can only oscillate in one plane. Yes it can pass through a filter on the same plane, but how the juddering feck does it pass through a plane at any angle (not 90 degrees) to it?
I guess I am looking for a 'classical physics' explanation which most likely doesn't exist.
As I am learning more about quantum mechanics I can see how powerful it is at prediction where 'classical physics' can not address, but what worries me is that there still seems to be a certain amount of 'assertions' used whereby they are still used in the mathematics simply because they work rather than being something 'derived' via explanation, observation or mathematical proofing.
(Something just to accept at this stage and carry on learning - probably)
The maths were embedded within quantum mechanics world of explanations, but essentially its about the probability of a photon to pass through the filter.
A vertical polarized beam of light passing through another vertical polarized filter has a 100% probability of passing through.
A vertical polarized beam of light passing through a diagonal polarized filter has a 50% chance of going through. And here is the quantum mechanics part..... even though each photon in the beam has the same properties, it still comes to a probability as to whether any particular photon will pass through the 45% (diagonal) filter or not.
Or more accurately the probability is COS^2(angle) where the angle is the difference in degrees between the filters. In this case 45degrees.
COS^2(45) = 0.5 .... which equates to a 50% probability.
But having sat through a video of how the maths presents the answer I am still at a loss as to what is actually happening around the simple wording of 'probability'.
Polarized light can only oscillate in one plane. Yes it can pass through a filter on the same plane, but how the juddering feck does it pass through a plane at any angle (not 90 degrees) to it?
I guess I am looking for a 'classical physics' explanation which most likely doesn't exist.
As I am learning more about quantum mechanics I can see how powerful it is at prediction where 'classical physics' can not address, but what worries me is that there still seems to be a certain amount of 'assertions' used whereby they are still used in the mathematics simply because they work rather than being something 'derived' via explanation, observation or mathematical proofing.
(Something just to accept at this stage and carry on learning - probably)
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