What is defined as trouble seeing objects clearly at close range?

The condition defined as trouble seeing objects clearly at close range is hyperopia, also known as farsightedness. Individuals with hyperopia can see distant objects more clearly than those that are close, leading to difficulty with tasks such as reading or other activities that require close vision. This occurs when the eyeball is too short or the cornea is too flat, causing light rays to focus behind the retina rather than directly on it. This can lead to symptoms such as eye strain, headaches, and blurred vision when viewing nearby objects.

In contrast, myopia, the other refractive error, causes difficulty seeing distant objects clearly, as it occurs when the eyeball is too long or the cornea is too curved, focusing light in front of the retina. Esophoria refers to a condition where the eyes tend to turn inward but doesn’t inherently indicate issues with close-range vision clarity. Lastly, retinopathy of prematurity is an eye condition that affects premature infants and can lead to vision impairment, but it does not specifically describe a refractive error related to the ability to see close objects.