So I understand we see things because light is reflecting off an object and that light is hitting our eye. It gets focused by our eye onto our retina. So it makes sense to me how someone can have bad eyesight, where everything goes equally out of focus. But how can a person be near-sighted, where light travelling a shorter distance (ie reflected from a closer object) is in focus but light travelling a farther distance is not in focus? And the reverse for far-sighted? How does the distance the light is traveling affect whether it can be in focus? It seems to me like everything should be able to be equally in focus, or equally out of focus
In: Biology
The distance the light travels isn’t the issue. The issue is how much the lens has to move to focus the light. It is like having a camera with a broken focus ring that can only move along a portion of the range it is supposed to. You have no problem focusing in the range it can still move in, but anything outside that range can’t be brought into focus.
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