What is the refractive error characterized by difficulty focusing on nearby objects?

The refractive error characterized by difficulty focusing on nearby objects is presbyopia. This condition is primarily age-related and occurs when the lens of the eye loses its elasticity, making it harder to focus on close-up tasks such as reading or knitting. As people age, the ability to accommodate, or adjust focus on near objects, diminishes, leading to this specific kind of vision challenge.

Presbyopia typically becomes noticeable in individuals around the age of 40 and can continue to progress with age. While other refractive errors like myopia (nearsightedness) and hyperopia (farsightedness) also affect vision, they do not specifically relate to age or the ability to focus on nearby objects in the same way as presbyopia does. Astigmatism, meanwhile, involves an irregular curvature of the eye that can cause blurry vision at various distances, but it too does not specifically relate to the challenges of near-focusing associated with aging.