Contact Lenses-How To Get The Most Out Of Them

Contact Lenses-How To Get The Most Out Of Them

Contactlenses and why we wear them.


We wear contact lenses mainly because we are vain.


But, they come in handy for any kind of sports, people even wear
them while swimming although you have to watch they don't float
out.


The Inventor of the contact lens concept was Leonardo da Vinci
in 1508,who sketched and described several forms of contact
lenses.


Hard contact lenses


Hard contact lenses are manufactured from a rigid material,
PolyMethylMethacrylate (PMMA). This substance is also combined
with other plastics to increase the oxygen permeability. Visual
acuity is perfect.


In 1632 Rene Descartes of France suggests the first hard
contact lens, which idea was actually developed in 1801 by
Thomas Young; resulting in a quarter-inch-long, water-filled
glass tube, the outer end having a microscopic lens,and he is
the first user. In 1887 a German Glassblower, F.E. Muller of
Wiesbaden,fabricates the first piece of glass acting as a
contact lens which could be seen through seen through and
tolerated.





Soft daily wear lenses have the main advantage that they allow
the eyes to be oxygenated through the lens. They're also easy to
adapt to and difficult to lose. You can get them in all kinds of
colours. Fantastic for wearing in sport activities. Not a
panacea for all vision problems and they have to be thoroughly
cleaned. Maximum lifespan 1 year.


In 1936 William Feinbloom, a New York optometrist, manufactures
the first American- made plastic contact lenses. These were
still hard lenses.


The first soft, water-absorbing plastic lenses were developed in
1960 by Otto Wichterle and Drahoslav Lim .


Disposable lenses 1.Extended-wear disposable


Soft lenses that you are able to wear for an extended period of
time, up to six nights, and then you can throw them away. They
hardly require any cleaning and have virtually no chance of
causing eye infection if user instructions are followed...














You can get them tinted and as bifocals. Your Vision may not be
as sharp as with other lenses and they do not correct all vision
problems. More difficult to handle.


2. Planned soft daily replacement lenses


Soft daily wear lenses that you replace on a planned schedule,
either every two weeks, monthly or quarterly. Require thorough
cleaning and disinfection. all vision problems. Not easy to
handle.


Colored lenses


There are 4 types of colored contact lenses: visible tints,
tints to enhance, color opaque tints and tints that filter light
Most of these colored contact lenses are available in plano form
(without visual correction), as well as for astigmatism, who
need bifocal correction, or who want a disposable or frequent
replacement lens.


Astigmatic lenses (toric) were first introduced in 1978 and
approved for distribution in the United States.


These lenses contain both a spherical and cylinder component to
correct prescriptions which have astigmatism. Lenses may be
thicker in one meridian or have modified thickness profiles to
enable the lens to maintain the correct orientation on the eye.


Bifocal contacts became available in 1982 for commercial
distribution.


There are a variety of designs in bifocals, essentially all
trying to provide a transition or reading zone for use at near
distances. The different designs include; + aspheric multifocal
- + simultaneous vision concentric - has either a central near
or distance zone with surrounding zone of opposite type to
centre (eg, centre near,distance surround) +
diffraction/holographic - based on diffraction grating
principles.


Eye exercises There seems to be a natural alternative to
eyeglasses, contacts, intacs, and even Lasik surgery, which is a
series of eye muscle exercises over a period of 30 days that
supposedly corrects your vision to quite an extent.


The validity of this method of vision correction has not been
fully proven.


About the author:


Frank Hague is very interested in Contact Lenses
http://www.contactlens-now.info
http://www.cataract-eye-surgery-bonita-springs.info
http://www.eye-surgery-now.info
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----If you want to make your Halloween costume really pop this year, color contacts can be really effective. But, Dr. Jack Schaeffer says some consumers are putting their eyesight at risk through improper use of color contact lenses.
Source: biz.yahoo.com