Which refractive condition requires no correction?

• A. Myopia
• B. Astigmatism
• C. Emmetropia
• D. Hyperopia

Answer: (C)

Emmetropia is when the eye’s optical power and length are matched so light from distant objects comes to a sharp focus directly on the retina, giving clear vision without glasses. Because there’s no refractive error, no correction is needed. In myopia the focal point lands in front of the retina, causing distant objects to blur and requiring minus lenses. In hyperopia the focal point is behind the retina, often needing plus lenses for clear near vision. Astigmatism results from uneven curvature, creating multiple focal points that blur vision in all distances and is corrected with cylindrical lenses.