= Magnifying glass
{wiki}
= Simple microscope
{synonym}
A <magnifying glass> uses a converging <optical lens> to present an upright enlarged <virtual image>. For <focal length> $f$ and eye <near point> distance $D$, the near-eye <angular magnification> is $D/f$ with a relaxed eye, or $1+D/f$ with the <virtual image> at the <near point>. These formulas assume negligible eyepiece-to-eye distance. With eye-to-lens distance $e$, object distance $u$, and the <virtual image> at the eye's <near point>, the <angular magnification> is $(D-e)/u$.
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