They say they only work for partial or mild colour blindness.
I'm guessing that if you don't see, for example, red clearly, they just manufacture them to dim out all other colours to bring the intensity down to match how well you see red. Then your brain adjusts to the dim view as if you were wearing ordinary dark sunglasses.
(Though I know colour vision and colour blindness is way more complicated, and not even actually RGB like a telly. And there are even some women that can see four distinct primary colours, so you could design a colour blindness test that 99% of women and 100% of men will fail, but only if you have your own chemical lab to manufacture the necessary inks).
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joefish It's hard for thee to kick against the pricks, Wed 22 Jul 2015, 18:27,
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Mmmmm chemical lab
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fluffybunnykiller Is feasting on the clitoris of life, Wed 22 Jul 2015, 20:44,
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