There are various types of lenses to correct the different visual defects that exist: Monofocal lenses: Monofocal lenses are those that correct nearsightedness, farsightedness or astigmatism. The entire lens has the same graduation. Progressive lenses: correct presbyopia. There are different graduations throughout the lens to correct the distance and near defects. The prescription is arranged…

Monofocal glasses are those that correct nearsightedness, farsightedness or astigmatism. The entire lens has the same graduation. In cases of people normally older than 40 years old, they need one prescription for distance and a completely different one for near because they start with eyestrain, in this case, they need a progressive lens that has…