Cataracts

The crystalline lens is a transparent lens inside the eye that focuses light entering the eye on the retina. 

As the lens ages the lens becomes less transparent and becomes opaque resulting in less light getting through to the retina and a reduction in vision. 

Is also results in the person experiencing more glare and halos around light and reduced contrast sensitivity. 

When buying glasses online it is important to make sure your lenses from your glasses and sunglasses have full uv protection