What condition occurs when parallel rays of light focus just in front of the retina in an unaccommodated eye?

Myopia, also known as nearsightedness, occurs when parallel rays of light focus in front of the retina. This condition arises when the eyeball is too long or the cornea has too much curvature, causing images of distant objects to appear blurred while close objects can be seen clearly. In an unaccommodated eye, which refers to the eye's resting state without any adjustment for focusing, the light rays entering the eye converge before they can reach the retina, resulting in the characteristic vision impairment seen in myopia.

In contrast, hyperopia (farsightedness) occurs when light is focused behind the retina, astigmatism is related to an irregular curvature of the eye's surface leading to distorted vision at all distances, and presbyopia is an age-related loss of the eye's ability to focus on close objects due to decreased flexibility of the lens. Each of these conditions affects vision differently, but myopia specifically is defined by the focal point being situated in front of the retina in an unaccommodated state.