Astigmatism might be the most misunderstood vision problem. Even the name is challenging to many people, who incorrectly call it “stigmatism.”
Like nearsightedness and farsightedness, astigmatism is a refractive error, meaning it is not an eye health problem; it simply is a problem with how the eye focuses light.
In an eye with astigmatism, light fails to come to a single focus on the retina to produce clear vision. Instead, multiple focus points occur, either in front of or behind the retina (or both).