lens medical definition

1. A ground or molded piece of glass, plastic, or other transparent material with opposite surfaces either or both of which are curved, by means of which light rays are refracted so that they converge or diverge to form an image.
2. A transparent, biconvex body of the eye between the iris and the vitreous humor that focuses light rays entering through the pupil to form an image on the retina.

Related Forms:

• lensed adjective

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lens

Light passing through double-convex lens (top) and double-concave lens. In each drawing, f indicates focus.