I recently learned about how light polarization was discovered, by Malus in the early 1800s when he observed the light reflecting off a cathedral window through a chunk of calcite (iceland spar). You normally see two copies of the glare, due to the birefringence, but rotating the crystal can make one of them disappear.
I tried it with a lightbulb reflecting off a dish of water. It works!
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u/starkeffect 23h ago
I recently learned about how light polarization was discovered, by Malus in the early 1800s when he observed the light reflecting off a cathedral window through a chunk of calcite (iceland spar). You normally see two copies of the glare, due to the birefringence, but rotating the crystal can make one of them disappear.
I tried it with a lightbulb reflecting off a dish of water. It works!