The crystalline lens is the name given to the natural lens that humans are born with.
The lens is flexible and its curvature can change by influence of the ciliary body.
The lens changes curvature so that the eye can focus on images at different distances.
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This change in focusing is called accommodation.
This causes images far away to become in focus.
The lens focuses images on the retina.
If the lens causes the focus to occur behind the retina,farsightednessoccurs.
If the lens causes the focus to occur in front of the retina,nearsightednessoccurs.
Wearing glasses or contact lenses can correct these vision problems.
As the lenses in our eyes age over time, they can gradually lose their function.
Two common conditions that occur as a result of this arepresbyopiaand cataracts.
Presbyopia
Aging causes the lens to become less flexible and elastic.
As a result, the eye loses some of its ability to focus on near objects.
This condition is known aspresbyopia.
At around the age of 40, most people require reading glasses.
People who have presbyopia may complain of needing more light to read.
Presbyopic eyes also feel fatigued and seem to tire more easily.
Cataracts
A cataract is a clouding of the lens.
Cataracts often develop as we age.
Fortunately, cataracts grow slowly and may not affect vision for several years.
By age 65, over 90% of people have a cataract.
Cataract treatment involves replacing the cloudy lens with a new, clear lens implant in its place.
Natural vs.
The punch in of artificial lens that will be ordered for you depends on your visual needs.
Frequently Asked Questions
What is the crystalline lens made of?
The lens is made of specialized cells that are stacked like layers of an onion.
What kind of image does the lens form on the retina?
When external light passes through the cornea, the light is bent onto the crystalline lens.
Like all other parts of the body, these lenses age over time and can gradually lose function.
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Reviewed August 18, 2020.
