What is the lens?
The lens is the part of the eye that allows it to adapt to light. Outdoors, especially in sunny weather, it lets you filter out the various UV rays.
The lens acts as a natural filter of the sun's rays, but it does not become fully operational until adulthood. Its role as a protective filter only begins at the age of 12.
Before that age, children are very sensitive to UV rays because the lens lets through more than 75% of UV rays.
> From 0 to 1 years: only 10% of UV rays are filtered, which means that 90% of UV rays reach your child's retina.
> From 1 to 12 years: only 40% of UV rays are filtered, 60% of UV rays still reach the retina.
> From 12 years: the amount of UV rays that pass through gradually decreases due to the lens becoming opaque and beginning to effectively play its role as a natural filter of UV rays.
Further information on "the ages of eyesight" is available on the ASNAV website (the French national association for improving vision).
To learn all about how the lens works, check out our article on the eye and the lens.
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