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Optics

Near Point & Far Point

The closest and farthest distances at which the human eye can focus objects sharply on the retina.

Governing formula Near Point ≈ 25 cm (Normal adult eye), Far Point = ∞
SI unit m (or cm)

In depth

Myopia (nearsightedness) brings the far point closer than infinity (corrected with concave lenses); hyperopia (farsightedness) moves the near point further than 25 cm (corrected with convex lenses).

Examples in the real world

A young adult with normal vision focusing comfortably on a book at 25 cm and stars at infinity.