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Lens (vision)


Light from a single point of a distant object and light from a single point of a near object being brought to a focus by changing the curvature of the lens.

The lens or crystalline lens is a component of the eye. In concert with the cornea, it refracts light, focussing it onto the retina.

The lens is clear and flexible; its curvature is controlled by ciliary muscles . By changing the curvature of the lens, one can focus the eye on objects at different distances from it.

The lens is about 5 mm wide and has a diameter of about 9 mm for an adult human (though these figures can vary). The lens is included into the capsular bag , maintained by the zonules of Zinn .

Diseases of the eye

  • A cataract is when the normally transparent crystalline lens develops opacities and leads to blurry vision.

See also


01-04-2007 01:16:19
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