Astigmatism

A common refractive error caused by an irregularly shaped cornea or lens, resulting in blurred or distorted vision at all distances. The cornea is shaped more like a rugby ball than a sphere, causing light to focus on multiple points rather than one. Astigmatism frequently co-occurs with other refractive errors such as myopia and hyperopia, and is particularly relevant to accessibility because it affects how users perceive on-screen content — sufficient contrast, appropriate font sizing, and avoiding thin or low-weight typefaces can significantly improve readability for people with uncorrected or partially corrected astigmatism.