Farsightedness (hyperopia) occurs when the eye is too short for the cornea's curvature. Light rays entering the eye focus behind the retina, and as a result a blurred image is produced.

People with farsightedness can usually see pretty well until they are in their 30's or 40's. Then they begin to lose their ability to read, and after a few more years, they lose their ability to read and to see far away. This is different from presbyopia or age related loss of reading vision.