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Intro
Hyperopia (i.e. farsightedness) is much less common than myopia
or emmetropia. It is typically in the +1.00 to +4.00 diopter range,
rarely it can be as high as +8.00 diopters.
Optics
 In
contrast to myopia, hyperopia occurs when the eye is too short for
the power of its optical components. In hyperopia, the cornea is
not steep enough and light rays hit the retina before they come
into focus. In the picture above the light rays are shown to focus
behind the eye (arrow). Distant objects appear blurred, and nearby
objects are even more fuzzy. Most farsighted individuals need corrective
eyewear to see clearly at all distances.
Spectacle Correction
Correction of hyperopia requires a lens which is convex (i.e. thicker
in the middle than the edges). This acts as a magnifier, and causes
objects to appear bigger by 2% per diopter. For this reason hyperopes
while wearing their spectacle correction, appear to have "big"
eyes. Optical aberrations and decreased peripheral vision occur
are likely to occur with large amounts of hyperopia.
Contact Lens Correction
Contact lens correction reduces the optical problems that plague
spectacle lenses, but they have their own unique problems including
high-maintenance care solutions, corneal warpage, corneal suffocation,
corneal infections, and eyelid allergies.
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