Question Title: Farsightedness

Posted by Rachel B on June 24, 1999 at 11:49:52

Hi there,

A friend of mine is farsighted although she thinks that if you wear
convex lenses (for nearsightedness) she will become less
farsighted and even shorsighted. Is it true that you can change
like this as I do not think that you can.

Regards

Rachel

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Posted by HFHS MD - NI on June 24, 1999 at 12:06:14

People who are farsighted see well in the distance but not at near. The younger you are, the eye can compensate for this. As you get older, you cannot see well near or far. Nearsighted people can see better up close but not in the distance. The eye cannot compensate for this. Both can be corrected with glasses.

If a nearsighted person is overcorrected with glasses, it is the same as being farsighted. Similarly, if a farsighted person is overcorrected, it is the same as being nearsighted. This does not change the actual status of the eye but only occurs while the glasses are worn.

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Posted by Rachel B on June 25, 1999 at 04:43:00

I still don't really get it....so if she is farsighted and wears
glasses that suit shortsighted people she will become shortsighted
herself after a while or she will only be shortsighted while wearing
the glasses.....an eye doctor surely can't give her convex lenses when
really she needs concave lenses or is it up to what she wants herself?

Can people who are farsighted see through convex lenses???

Regards !

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Posted by HFHS MD-JL on June 25, 1999 at 12:19:45

Yes, the key is that this occurs only while wearing the glasses. This does not permanently affect the eyes. A near sighted person can wear concave lenses and visa versa for a far sighted person, but the vision will not be good through them. I hope this has helped. You can also look in a high school physics book to review the basics of optics if you are interested.

HFHS MD-JL

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