How do you tell if someone's glasses are converging or diverging lenses?

Or, in other words, how can you tell if a pair of glasses is for farsightedness or nearsightedness (respectively)?

http://webphysics.davidson.edu/mjb/phy22...

I came across this page while looking for a picture with google images and was wondering what the answer is?

Farsighted (Hyperopic) person has a converging lens= magnify=eyes look bigger

Nearsighted (Myopic) person has a diverging lens=minify= eyes look smaller

In the picture it is really hard to tell... but it appears they are nearsighted. I also looked up John Lennon and sources say that he was myopic/nearsighted. If the eyes look slighty smaller behind the lenses or if you see the side of their face through the lenses and it appears to be inward from where it actually is.... then you know they are wearing diverging lenses for myopia.
People that are farsighted need (+) plus powered prescription lenses that can magnify the eyes.... and nearsighted people need (-) minus powered prescription lenses which can minify the eyes.

both are nearsighted [myopes] ,look into the lens of the glasses ,the line of the side part of the face that appears through the lens ,if it's displaced inward this is minus lens ,if it's displaced outwards this is positive lens

If a person is wearing their eyeglasses, the simplest way to find out is if it magnifies their eyes or not. If it magnifies it, they are farsighted (hyperopia). If it doesn't than they are nearsighted (myopia). Another way to figure out a converging or diverging lens, is when you take a look at the lens carefully sideways. If the lens is thicker in the middle and thinner on the outer edges, they are farsighted and if the lens are thicker on the outer edges and thinner in the middle, they are nearsighted =) Hope this finds you informative.


ophthalmic lab tech