Contact lenses are corrective lenses just
like glasses, but they are designed to work
when fit tightly against your eye instead
of a half-inch or so out in front of them.
Unlike a pair of glasses, contacts are generally
undetectable when worn and can give you all
the benefits of seeing clearly without the
change to your appearance that glasses bring.
Contact lenses are of two types:
- Rigid gas permeable lenses are permanent
in the same way as glasses are. The lenses
generally last at least a year, and you maintain
them with regular cleaning overnight. Lately,
extended wear lenses have made a comeback
with a new material that allows you to wear
them continuous for a week, or in some cases,
a month rather than putting them in and taking
them out each day.
- Soft or disposable lenses last any where
from a single day up to two weeks, with the
latest improvement a version that may be
worn for an entire month. As the name implies,
these lenses are meant to be worn once, or
comparatively fewer times, and then discarded
without the muss or fuss of cleaning.
Contact lenses may also have
- advanced shapes: until recently, contact
lenses had only one focal length, but now
bifocal (near and far correction in the same
lens) and toric lenses that correct astigmatism
(an uneven focus because of variations in
your cornea) are available.
- tints: tinting the lenses is purely cosmetic
and can deepen or even change your eye color.
- UV coating: some brands add a protective
element to the lens to block ultraviolet
light and reduce the risk of cataracts from
exposure to sunlight.
Because of the variety of prescriptions,
contact lenses are generally ordered for
later pick-up or delivery, which means that
buying online not only saves you a trip to
the store to place your order, but also allows
you to price shop among sellers of name brand