Complete annihilation of light through polarizers

AI Thread Summary
Using two crossed polarizers should theoretically result in complete darkness, but in practice, this is not achieved due to the imperfections in real polarizers. Instead of total annihilation of light, some light still passes through, leading to a change in color rather than complete blackness. The discussion highlights that perfect polarizers, like frictionless surfaces, do not exist in reality. The inability to achieve true darkness is attributed to these imperfections in the experimental setup. Therefore, the observed phenomenon is a result of the limitations of the polarizers used.
quietrain
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Hi,

when i am doing an experiment that uses two polarizers (Cross) to achieve complete annihilation of light,

why am i not able to see complete darkness when i look at the light source from the end of the polarizers, but rather the light source changes to a different color

for example, if i have a blue light source, i see it become dark blue, but never really black.

so is there a reason? theoretically i am suppose to kill 100% of the light right?

thanks!
 
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The polarizers are imperfect.
 
so its a fault on the experiment apparatus?
 
Yes. Perfect polarizers are in the same category as frictionless surfaces.

You might suggest to the http://www.lhup.edu/~dsimanek/ideal/ideal.htm that they add perfect polarizers to their catalog. :smile:
 
haha ok thanks!
 
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