What does emmetropia indicate?

Emmetropia refers to a state of perfect vision where the eye is able to focus light directly on the retina, resulting in clear vision without the need for corrective lenses. This condition is often described as normal vision, which is frequently represented by the measurement of 20/20 vision. In essence, a person with emmetropia can see clearly at both near and far distances without any refractive errors, such as myopia (nearsightedness) or hyperopia (farsightedness).

This makes the concept of emmetropia integral to understanding visual acuity and eye health, distinguishing it from conditions that require corrective lenses or indicate visual deficits.