What does it mean to be "farsighted?"

  The anatomy of hyperopia, or farsightedness

The anatomy of hyperopia, or farsightedness

In the simplest of terms, people who are farsighted have an easier time seeing far away than up close.

Why is this? Well, a farsighted eye is an eye that is either too short or too weak. Take a look at this picture. The image is focused behind the retina, not right on the retina where it will be sharpest. You can imagine that this could happen either because the eye is too small, or the focusing power is too weak.

Now, here is where hyperopia is a bit different from simply the opposite of myopia. Young people have the ability to accommodate -- to increase the power of their lens focus -- and this can neutralize farsightedness. Hence, a young person who is farsighted may have no trouble at all seeing far away or up close, even if their prescription is high, because there lens can change shape and focus the image. The natural decline of this ability with age is called presbyopia, and is the reason why many people need reading glasses beginning in their 40s and 50s.

If a person's hyperopia is significant enough to warrant correction, the available options are the same as those we discussed last time, for myopia, namely: glasses, contact lenses, and corrective surgery.