What does the sign in front of your prescription mean?

Question

When the sign is positive what does it mean?

When the sign is negative what does it mean?

Answer 1

Nice explanation Shannon...but you got it all  backwards

Answer 2

farsighted

nearsighted

Answer 3

positive  farsighted, this means you see better at distance

negative nearsighted, means you see better at near

Answer 4

The prescription is a relative measure of the thickness of the lens at center with flat glass. Positive means thicker in the middle than the edge, farsightedness. Negative means thinner in the middle than at the edge, nearsightedness. There are other components to the prescription which account for certain defects, such as astigmatism, which is where the eye sees crossed lines as in a plus sign with either the vertical or horizontal part indistinct as compared to the other part. For me, I can clearly see vertical lines, but I do not see horizontal lines very well without my glasses. Without my glasses, I see news print as a series vertical lines of varying width and height. The horizontal parts of the printed letters almost disappear completely.

Answer 5

(+) Nearsighted

(-) Farsighted

Nearsighted means you can see FAR but not up close

Farsighted means you can see NEAR but not far.

Its sounds BACKWARDS i know.

Just think of it like this:

+ (NEAR) = nearsighted=can't see up close

- (FAR) =farsighted=can't see far