How does polarised sunglasses work
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Light travels through the air kind of like a dolphin jumping behind a boat, in a straight line, but also Up/Down motion. Since light goes up/down so quickly you can think of it less as a laser point, but more of something like a 2×4 flying vertically through the, it has a definite “height” to it’s motion.
BUT most light sources aren’t “in sync” with each other, meaning some light is going up down, some side to side, some every possible angle in between.
So a polarized filter is basically just like a set of window blinds, tons and tons of tiny slits stacked on top of each other. Imagine a 2×4 coming through window blinds, *only* 2x4s that are perfectly sideways can squeeze between the slits perfectly. Any other orientation of 2×4 would hit the slats and get caught. That’s a polarizing filter.
Since “scattering”, like reflections off a wet road, cause this crazy variance in light, filters like this help reduce “Glare” caused by the scattering by forcing only one orientation of light through the slats.
Most TVs and cellphone screens have a filter on them now at the source, you normally don’t notice it but if you wear polarized sunglasses and tilt your head while looking at your phone or TV, you’ll notice the image appears and disappears. That’s what’s happening, the screen is only emitting light in a very specific orientation, and your glasses are blocking that orientation so the screen appears “dark” to you.
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