Leonardo Davinci
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How Have Contact Lenses Changed Over the Years?
Like all useful inventions, contact lenses have evolved since they were invented in the mid 1930's and popularized in the early 1970's. But what of this evolution and how did it come about?
Leonardo Davinci the Father of contact lenses?
Many people believe that Leonardo Davinci's Codex of the Eye, Manual D described using a bowl of water to correct vision, but there is some debate as to if this was the case. Many scholars now believe that Davinci was merely observing the functions of the eye and that the water was incidental to that observation.
There have been many incarnations of the contact lens since The Codex of the Eyes' introduction in 1508, but the one that is most familiar to modern day contact lens wearers was created by George Butterfield, the Oregon optometrist who used the designs of previous inventors to create a hard plastic device that covered the entire cornea. It wouldn't be until the later 1950's that the hard corrective lens became smaller and easier to use.
Hard lenses
The first contact lenses were made of glass then graduated to plastic. In 1920, a German optical company called Zeiss made glass contacts alongside another Germany based company. Although they were significantly corrective, they were hard to wear and wouldn't remain seated for very long.
Soon, manufacturers created a lens that was a combination of both plastic and glass. These contacts were perfected in 1936 by a corporation named the Rhom and Haas Company. Rhom and Haas created a malleable substance called polymethylmethacrylate (PMMA), a clear plastic that would be the foundation of contact lenses for forty some odd years.
The design would not truly change until an Oregon based physician named George Butterfield designed a lens that was shaped very similar to the cornea in 1950. This made contact lens far easier to wear and easier to manipulate.
Still, hard contact lenses can be hard to wear for extended period of time, a fact that is true even until this very day.
Soft lenses
Soft lenses, also called hydrogels, were an invention of Professor Otto Wichterle, a Czechoslovakian polymer chemist. Upon creating hydroxyethylmethacrylate (HEMA), the chemist soon learned that the pliable material was fear easier to wear than its predecessors. In 1972 Bausch and Lomb took the concept and created the first soft contact lenses.
Many contact lens wearers prefer hydrogels because of their pliability and comfort. The only con is that they can be hard to use and can get lost somewhat easily. However, with constant wear, the problems associated with the use of soft contacts usually subside or are greatly minimized.
Toric and bifocal lenses
As contact lenses became more sophisticated they began to be utilized for all manner of vision correction, including conditions that were once difficult to treat without glasses. For instance, contacts to correct astigmatism like Torics were soon created. Bifocal lenses also exist and can help correct problems that were assisted by horrendously thick eyeglasses once upon a time.
Today, contact lenses are a mainstay when it comes to vision correction. Although one can also consider other alternatives like eyeglasses, most prefer to use contacts lenses. Still others may opt for a combination of the two, using contacts for daily activities and glasses for reading or studying.
When it comes to corrective eyewear only you and your doctor can know for sure what will work best for you. Do your homework and talk with your optometrist about all your choices prior to making such a big decision. Should you choose contact lenses you will not only join countless millions who did the same thing, you will be paying homage to the brilliant pioneers Who Made such a medical feat possible.
About the Author
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Leonardo da Vinci
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 The Notebooks of Leonardo Da Vinci Complete See Reviews For This Product DescriptionThis book was converted from its physical edition to the digital format by a community of volunteers. You may find it for free on the web. Purchase of the Kindle edition includes wireless delivery. |
 The Notebooks of Leonardo Da Vinci - Volume 2 See Reviews For This Product DescriptionThis book was converted from its physical edition to the digital format by a community of volunteers. You may find it for free on the web. Purchase of the Kindle edition includes wireless delivery. |
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Leonardo Davinci (Mixed media product) $9.89 Painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist, and writer, Leonardo da Vinci was a genius who was well ahead of his time and the best example of the Renaissance man. T... |
