What refractive error is characterized by parallel rays focusing in front of the retina?

Myopia, commonly known as nearsightedness, is characterized by the inability to see distant objects clearly because parallel rays of light focus in front of the retina. This occurs when the eye is either too long or the cornea has too much curvature, causing light rays to converge too early. As a result, while close objects may be seen clearly, distant objects appear blurry.

In contrast, hyperopia, or farsightedness, occurs when parallel rays focus behind the retina, making nearby objects difficult to see clearly. Strabismus refers to a misalignment of the eyes, not a refractive error, and emmetropia indicates a normal refractive state where light focuses directly on the retina. Understanding these distinctions is vital for diagnosing and managing refractive errors effectively.