Why can even a small injury to the cornea have a effect on vision

As light enters your eye, it gets refracted, or bent, by the cornea’s curved edge. This helps determine how well your eye can focus on objects close-up and far away. If your cornea is damaged by disease, infection, or an injury, the resulting scars can affect your vision. They might block or distort light as it enters your eye.

Explanation:

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