Vision Disorders

When the eye's axial length is shorter than normal, close objects appear blurry. This is called hyperopia or presbyopia, commonly termed long-sightedness. It may be latent—meaning the eye can compensate through accommodation, the ability to adjust; or it may be absolute—in which case correction requires convex or positive lenses. Around middle-age, the eye's ability to accommodate deteriorates, which is why almost all people over 45 or 50 years of age require glasses for close-up vision. Irregular curvature of the cornea or lens will produce the same deficit.