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Dispersion does come up; the last time I got new lenses for my glasses, one of the brochures on the table had the Abbe number [0] listed for various materials.

Generally lenses with the highest refractive indices have fairly low Abbe numbers and have a lot of dispersion; a lower dispersion lens would have to be thicker and heavier (and thus increase geometric distortion).

There are some fancy extra-low-dispersion glass formulations used in camera lenses, but apparently these are generally more fragile than typical glass and that's not suited for glasses.

I also asked my optician if there were any achromatic doublet glasses, but he told me that those would end up having to be extremely thick and heavy.

[0] https://en.wikipedia.org/wiki/Abbe_number



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