Farsightedness means it’s easy to see things that are far away, but your close-up vision (near vision) is blurry. The technical term for farsightedness is hyperopia. According to the National Eye Institute, it affects 5 to 10 percent of Americans.
To understand farsightedness, it’s important to understand how the eye works. Two parts of the eye are responsible for focusing: the cornea and the lens. The cornea is the clear front surface of the eye. The lens is a structure inside your eye that changes shape as you focus on objects.
The cornea and lens work together to refract, or bend, incoming light. Then they focus that light onto your retina. The retina is at the back of your eyeball. It receives visual information and sends it to your optic nerve. Your optic nerve carries that information to your brain.
A perfectly formed, curved lens and cornea result in a perfectly focused image. If your cornea is too flat, your eye can’t focus correctly.
There are varying degrees of farsightedness, depending on the eyes’ ability to focus on close-up objects. If you can only clearly see objects that are very far away, you’re severely farsighted. Generally this is easy to correct.
Causes of Farsightedness
A flat cornea is one cause of farsightedness. You can also be farsighted if your eyeball is shorter than normal. This causes light to focus behind your retina instead of on it.
You’re more likely to have farsightedness if your parents do. It often develops in adults as the lenses of the eyes age.