Final answer:
A cataract is cloudy formation in the lens of the eye that impedes light and can cause blurred vision. Cataracts contribute significantly to blindness, but preventive measures and proper treatment can manage the condition effectively.
Step-by-step explanation:
Clouding that develops in the lens of the eye is known as a cataract. A cataract is cloudiness in the lens of the eye, which can lead to a decrease in vision because it impedes the passage of light into the eye. It is important for light to enter the eye properly so the eye can see clearly. Cataracts can cause light to be dispersed or diffused, which results in blurred vision. Cataracts are a significant cause of blindness worldwide, accounting for 50% of all cases. Prevention, such as wearing sunglasses with UV protection, can help protect against the formation of cataracts. Furthermore, when performing a procedure to repair a retinal tear, laser light must be shone directly into the eye with parallel rays to ensure precise spot-welding and to avoid further dispersion of the light.