The other day while checking out a polarized job, i took a sample lens and rotated it 90 degrees, as i always do to make sure they are polarized correctly. The reaction instead of the lens turning from light to darker was instead kind of a streak. I then realized that the lenses in the frame were cr-39 and my tester was a polarized poly lens. question is why did i not get the normal reaction you get, when you turn one over the other and there the same material?
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