People who are very nearsighted have those weird sort of lens when viewed from t...

Someone · on Dec 18, 2022

From the slide show on this side, this is such a lens. Because of the high diopter, the center part is even smaller.

It seems they correct a bit for that by moving the glasses closer to the eye. That increases the angular extent of the lens a bit for the wearer.

melony · on Dec 18, 2022

I think those are high index lenses, not normal lenses. I might be wrong though.

lostlogin · on Dec 18, 2022

I don’t think that changes how the effect works though, just reduces the thickness of the glasses.

I’m very much not expert at this, I just help a child with poor eyesight, and every upgrade that reduces weight and thickness is much appreciated.