Why can't we get synthetic sapphire eyeglasses? Abbe number 72.2 (!!!!) and high index of refraction.
Glass lenses are actually rather expensive compared to CR39 which is almost as good (within 1.0 Abbe value diff) & better at blocking UV.
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But people pay big $ for the awful polycarbonate, etc. lenses all the time, with *awful* chromatic aberration. I'd pay 5x that for sapphire.
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wait, PC is awful? I like how indestructible it is, and it lets me use nearly nonexistently thin frames
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Yes, Abbe value of 30.
End of conversation
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Oh that's another issue with sapphire: uncoated, it passes down to 195nm (UVC) with almost zero attenuation.
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so you'd need to wear glasses under your glasses. I fail to see the problem with this. Imagine the memes
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The way I look at that, wrt UV, my eyes are still no worse off than people who don't need glasses.
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You could do a coating though if it doesn't affect the optical properties badly.
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So the TiO2 thin film coating I put on my glasses b/c it annoys me when they fog up apparently blocks everything below UVA.
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A film that blocks everything below ~480nm would probably actually help a lot with chromatic aberration.
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Don't you mean ~415nm? 445nm for instance is what InGaN blue LEDs emit...
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No, I specifically mean getting rid of the awful blue-led light that spatially diverges so much from everything else. :-)
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