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lens

(lenz)
A clear disk that focuses light, as in a camera or microscope. In the eye, the lens is a clear, curved structure at the front of the eye behind the pupil. It focuses light rays that enter the eye through the pupil, making an image on the retina (light-sensitive layers of nerve tissue at the back of the eye).
Eye anatomy; two-panel drawing showing the outside and inside of the eye. The top panel shows the outside of the eye, including the eyelid, pupil, sclera, and iris. The bottom panel shows the inside of the eye, including the cornea, lens, ciliary body, retina, choroid, optic nerve, and vitreous humor.Enlarge this image in new window
Anatomy of the eye showing the outside and inside of the eye, including the eyelid, pupil, sclera, iris, cornea, lens, ciliary body, retina, choroid, optic nerve, and vitreous humor.
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