This is the term doctors use for farsightedness
(also called longsightedness). Opposite to myopia, the eyeball is too
short or the cornea is too flat. The rays of light aren’t bent inwards
enough to be able to come together before they hit the retina and so the
image is blurred. If you imagine the light rays continuing on past the
retina (which obviously they can’t), they would eventually meet at a
point behind the eye.
a)
normal
eye b) longsighted
eye, with light focused behind the eye
(images courtesy of Refracted, Inc.)
Younger farsighted people can make the light rays
bend in more by focusing with their eye muscle, which makes the lens of
the eye more round. This allows them to see clearly. If the hyperopia is
too much, or you are over about 45 and your lens can’t bulge any more,
you will need glasses to see up close. If the farsightedness is high, or
the lens won’t bulge at all, distance objects will also be out of
focus, as the eye can’t even bend these gentler rays enough to get
them to meet on the retina. Hyperopia is also measured in dioptres
(+2.50D), and doctors might refer to these patients as hyperopes
for convenience.
To
learn more about needing reading glasses, click
here
