Accommodation and natural lens

The primary function of the eye is to process images by focusing light rays on the retina in the back of the eye. The cornea, the outermost part of the eye, starts this process, and the transparent natural lens inside your eye completes the focusing process. The lens which is located directly behind your iris (the colored part of your eye) and can change its curvature based on the distance between your eye and the objects you are viewing. The process of changing the lens curvature is called “accommodation.” A person who is born with a natural lens in each eye that focuses on objects near and far. The natural lens allows most people under the age of 40 to quickly change their focus (accommodate) from a near object to a far object, or vice versa, without difficulty. However, as we reach our mid-40’s, the aging process makes the lens less flexible, and the lens slowly loses its ability to shift between near and far images. This loss of accommodation is called ‘presbyopia,’ and many patients eventually need bifocals or reading glasses to clearly see near objects.

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Channels: Medical

Tags: Accommodation and natural lens

Uploaded by: ( Send Message ) on 09-11-2010.

Duration: 0m 35s