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The idea of wearing some sort of lens in order to
improve vision may seem like a new invention, but nothing can be further
from the truth. In fact, the first documented theory of using some sort
of lens to aid vision dates back to 1508, when Leonardo da Vinci created
very detailed drawings of lenses to place over the eye to aid in vision.
During his time, however, the proper materials and technology simply
were not available to create contact lenses.
A) The evolution of
the contact lens: Despite da Vinci’s failed
efforts to create the contact lens, the dream still lived on. Man
continued to seek methods for improving poor eye site in an unobtrusive
manner. In fact, Rene Descarte envisioned the first corneal contact
lens, which only covered the corena rather than the entire eye, in 1632.
In 1801, Thomas Young continued the research into its development and
also demonstrated that he could improve his own vision by using a ¼”
long glass tube filled with water.
21 years later, Sir John
Herschel suggested making a mold of the eye to create contact lens to
fit exactly to the eye’s surface. This concept wasn’t made possible for
another 60 years when anesthesia was developed. At this time, in 1887,
F.A. Muller made a transparent lens to cover a diseased eye. This
technique was used for many years, despite the fact that the lenses were
very heavy and could only be worn for short periods of time.
B)
Modern day contacts appear: In 1888, the first contact lenses as
we know them today were developed by A.E. Fick. Fick used Herschel’s
idea of creating a mold to begin experimenting with rabbit eyes. Then,
he used cadavers to perfect the method and made glass contact lenses to
help with his own vision. These first contacts, however, were very
uncomfortable. As a result, Fick only wore them for a couple hours.
The
advance in contacts were slow moving following this initial invention
because they were so uncomfortable and because the lack of oxygen flow
caused by the glass contacts, they were unhealthy for the eyes.
Scientists did, however, begin to actively pursue the creation of a
material to be used for contact lenses that would both correct vision
and allow for oxygen to reach the eye. In addition, researchers began
trying to understand how long contacts could be safely worn and whether
or not one lens shape could be made that would be able to fit all eyes.
C)
A new material is born: In 1938, true advancements in contact
lens development began to emerge when Obrig and Mullen created the first
all plastic contact lens from polymethymethacrylate (PMMA). This
material was far more comfortable than glass, weighed less, and was
safer for the eye. These contact lenses covered the entire eye, making
them what is referred to as “scleral lenses.” This type of lens was
originally created with glass contact lenses to help prevent them from
falling out because of their own weight. The unfortunate side effect
with glass contact lenses was that this prevented oxygen from reaching
the eye completely.
In 1945, the American Optometric Association
officially recognized contact lenses ad an important area of the field
and finally, in 1947, Kevin Touhy developed contact lenses made of
plastic. In 1950, Dr. George Butterfield developed corneal lenses that
followed the curvature of the eye rather than lying flat. These lenses
are what are known today as “hard” contact lenses, but they were the
only type of contact lenses available for about 20 years. Of course,
these contact lenses still had a long way to go to get to where contact
lenses are today. These lenses still did not allow the eye to breathe
properly and were still uncomfortable to wear.
D) Water leads the
way: In 1960, Otto Wichterle and Drahoslay Lima created
hyrdroxyethylmethacrylate, which was mostly made of water. This special
material was capable of being hard when dry, yet soft when wet. This led
the revolution to “soft” contact lenses. At first, these contacts were
difficult to handle and were not as effective in correcting vision
problems. In addition, scientists were concerned about their possible
lack of resistance to bacteria and other harmful contaminates. In 1971,
however, Bausch & Lomb managed to gain approval from the FDA to sell
these new contact lenses and the rest, as they say, is history!
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