The discussion revolves around the effects of rotating two polarizing films with respect to one another. Participants explore how the alignment of the filters affects light transmission and polarization.
The conversation is ongoing, with participants providing feedback on each other's statements and suggesting modifications for clarity. There is an exploration of how the angle between the filters influences light transmission, but no consensus has been reached on the precise wording or explanation.
Participants are navigating assumptions about light polarization and the mathematical relationships involved, particularly regarding the cosine function and its implications for light intensity through the filters.
mfb said:Right.
You can also comment on the polarization of the light after the second filter.
But you wrote:chef99 said:If the filters were rotated, in relation to each other, only the light parallel to the second filter would pass through.
If the filter axes are not parallel, and the first filter has polarized the light parallel to its own axis, then none of it is parallel to the axis of the second filter.chef99 said:The first filter would polarize the light along its axis.
haruspex said:But you wrote:
If the filter axes are not parallel, and the first filter has polarized the light parallel to its own axis, then none of it is parallel to the axis of the second filter.
Any ideas on how to modify the first statement above to resolve this?
That is what I meant, yes.chef99 said:So I should add:
after passing through the second filter, the polarization will be in the direction of the second filter.
Is that what you are talking about?
That is better, but arguably still not right. That wording suggests that if the angle between the current polarisation of the light and the direction of the filter is θ then the fraction that gets through is ##\cos(\theta)##. In fact, it is ##\cos^2(\theta)##.chef99 said:when the films are rotated, in relation to each other, only the component of the light that is parallel to the second filter passes through.
Ok, that makes sense. So when they are rotated, the amount that gets through is related to the degree of the angle between the two films? If they are parallel then all light gets through, if they are at a right angle no light gets through, and if they are at an angle in between then the amount of light that gets through is related to the angle.haruspex said:That is better, but arguably still not right. That wording suggests that if the angle between the current polarisation of the light and the direction of the filter is θ then the fraction that gets through is ##\cos(\theta)##. In fact, it is ##\cos^2(\theta)##.
Maybe just say that the fraction that gets through is related to the angle between the two in such a way that when parallel all gets through and when at right angles... etc.
Yes.chef99 said:Ok, that makes sense. So when they are rotated, the amount that gets through is related to the degree of the angle between the two films? If they are parallel then all light gets through, if they are at a right angle no light gets through, and if they are at an angle in between then the amount of light that gets through is related to the angle.