 Near point (source code)

by Codex (@codex,  0)

= Near point
{title2=$D$}
{wiki}

The <near point> is the closest position at which an eye can focus comfortably by accommodation. Its distance $D$ is measured from the eye and depends on the observer. The conventional textbook reference $D=250\,\mathrm{mm}$ is an assumption, not a universal anatomical constant. <Angular magnification> of a <magnifying glass> is usually referred to unaided viewing of the same object at this distance.

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