I haven’t ever really considered my vision to be particularly great – I usually need the assistance of glasses or contacts to have good vision. However, my vision is good enough that I often go around without the glasses.
If I meditate for a long time, I notice that my vision becomes a lot better. Not as good as with glasses, but there is definite improvement. It is like my eye muscles are stressed, and relaxing allows the lenses to work better.
My students with glasses are definitely not in the the middle range I am of sometimes needing glasses. If we swap glasses, I notice immediately that their prescriptions are extremely strong. When they wear my glasses, or don’t wear glasses, they hurt because their eyes have grown accustomed to the glasses.
I hope that someday my vision will improve to 20/20 without the need for any surgery at all. My vision certainly hasn’t declined the way most people’s do when wearing glasses for a long time.