How does a diverging lens correct near sightedness?

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kfcman289

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I know that the problem with near sightedness if that the image is formed before the retina, so to fix it you have to push the image back. But if a diverging lens has a negative focal length, which would make the image negative, wouldn't that put the image to the left of the diverging lens, and consequently make the object (since the image of the lens is the object of the eye) farther away from your eye? A farther object would cause an even shorter image distance and wouldn't that not be what you want?
 
The diverging lens creates an upright, virtual image at the focal point of the eye.

So it does produce an image that is to the left of the corrective lens, but at a distance the person can focus on.
 
The diverging lens creates an upright, virtual image at the focal point of the eye.

So it does produce an image that is to the left of the corrective lens, but at a distance the person can focus on.


OK, but then why wouldn't a converging lens work as well? Wouldn't to image also be placed in a distance that is close enough?
 
A converging lens with an object at infinity (or just beyond 2 focal lengths) would produce a real, inverted, and reduced image. So we would see everything upside down and small.
 
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