Unformatted text preview: se now that the two filters are offset by some angle θ. Regardless of
the angle, the first filter blocks half the light. If θ = 0, the second filter has no
effect. If θ = 90°, the second filter blocks the other half of the light. In general, when polarized light with an electric field of amplitude E passes
through the second filter, the amplitude will drop to E cosθ. Furthermore,
since the energy a wave carries is proportional to the square of its amplitude, the intensity of the light will be the original intensity multiplied by cos 2θ.
Blocking Light Continued on Next Continued on Next “Twisting” of Light
We know that if θ = 90° between two filters, then no light will
make it past the second one. At other angles light will pass
through both, changing the orientation of its electric field each
time. So, what if we arranged several polarizing filters so that the
angle between any two consecutive filters is less than 90°? The
answer is that light twists its way through the filters, even if th...
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This note was uploaded on 11/17/2011 for the course PHYS 121 taught by Professor Burgeson during the Fall '11 term at BYU.
- Fall '11