vision




80 % of all the information we receive is perceived by our eyes.

 

Discover the scientific explanation for the magic of sight and its defects.

 

Vision: How does sight work?

The optical system that enables visual perception is very complex.

  • The eye intercepts light.

  • An image of the external world is created on the retina.

  • The nervous system transmits this image to the brain.

  • The brain interprets the information received to form an image.

 

The crystalline lens: the organ that helps the eye adjust

The crystalline lens plays an essential role in vision. This lens contracts and expands to focus rays of light on the retina.
Like an autofocus camera lens, it helps to adjust images in accordance with the distance of the external object, a function that is called accommodation.

 

"Normal" eyesight

When the eye presents no visual disorder, images of near or far objects are formed on the retina through accommodation. The crystalline lens bulges in or out according to its distance from the object in order to create a focused image.

 

Visual disorders

Vision is blurred or deformed when the image of the object does not form on the retina. This type of visual disorder is called ametropia. There are three kinds of ametropia: myopia, hyperopia and astigmatism.

 

The natural changes in eyesight

After the age of forty, everybody, whether normally-sighted or ametropic, is affected by presbyopia. This is due to the natural aging of the crystalline lens, which hinders proper accommodation.


 
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