the first pair of glasses for astigmatism were invented in 1290.
the first pair of glasses for astigmatism were invented in 1290.
when were the first pair of glasses for astigmatism invented?
1290
the american scientist benjamin franklin, who suffered from both myopia and presbyopia, invented bifocals. serious historians have from time to time produced evidence to suggest that others may have preceded him in the invention; however, a correspondence between george whatley and john fenno, editor of "the gazette of the united states", suggested that franklin had indeed invented bifocals, and perhaps 50 years earlier than had been originally thought. the first lenses for correcting astigmatism were designed by the british astronomer george airy in 1825.
glasses
astigmatism causes difficulties in seeing fine detail. astigmatism can be often corrected by glasses with a lens that has different radii of curvature in different planes (a "cylindrical" lens), contact lenses, or refractive surgery.









































astigmatism is quite common. studies have shown that about one in three people suffers from it. the prevalence of astigmatism increases with age. although a person may not notice mild astigmatism, higher amounts of astigmatism may cause blurry vision, squinting, asthenopia, fatigue, or headaches.
astigmatism (optical systems)