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This year (i.e., 2008) will be the 500th anniversary of the original conception of the contact lens. Its present form is the result of centuries of imaginative thinking, scientific reasoning and technological advances. In 1508 Leonardo da Vinci became the first person to conceive of a contact lens. He did not propose this as a way of correcting vision, but as a way of understanding the manner by which the eye is able to preserve the visual clarity of an object as the object moves closer or further within the field of view. Leonardo da Vinci's remarkable brainchild was not feasible at the time because of technological limitations. The next development was a hypothetical method put forth by astronomer Sir John Herschel in 1827 for grinding and shaping them to match the shape of the surface of an eye. As part of this methodology, Sir John Herschel suggested that a mold of the eye be taken in order to guarantee that their shape be a precise fit to the shape of the eye. Nonetheless, the technological ability to create a mold of the eye was not present during the first half of the 19th century. With the invention of anesthesia in 1884, a glassblower by the name of F.A. Muller constructed the first glass contact lens in 1887. However, the first version to correct vision was not created until 1888 by Swiss physician A.E. Fick and French optician Edouard Kalt. Originally they were made of glass and covered the entire front of the eye. The glass deprived the eye of oxygen putting its long-term health in peril. Furthermore, they were heavy and uncomfortable so that most people were only able to wear them for a few hours. Plastic was not used within their construction until the 1930s. These plastic forms were lighter and more comfortable than their earlier counterparts, but still covered the entire front of the eye and prevented oxygen from reaching the eye. In the late 1940s, the American optician Kevin Tuohy manufactured a plastic version that covered only that portion of the eye known as the cornea. Nonetheless, his contribution still did not allow the majority of the eye to receive oxygen. Tuohy's innovation is commonly referred to as a form of hard contact lenses. Hard lenses continued to improve during the next two decades, but still became uncomfortable to wear for lengthy periods of time. A remedy came from their soft counterparts that were first manufactured in 1971. Soft contact lenses were the result of years of work by the Czechoslovakian chemist Dr. Wichterle who had been experimenting with a type of plastic known as hydroxyethyl methacrylate (HEMA). These soft alternatives are hard when dry, but soft when wet. This makes them more comfortable to wear, but more difficult to apply. The first gas permeable contact lens was FDA approved in 1979. Like their soft counterparts, gas permeable forms permit oxygen to reach the eye and are comfortable to wear. Unlike their soft counterparts, gas permeable varieties are easier to handle. The most recent development has been the introduction of silicone hydrogel contact lenses into the European market in 1999 and into the US market in 2001. Silicone hydrogel negate or mitigate a number of health issues associated with the eye such as corneal swelling, neovascularization and progressive increases in myopia. Contact lens manufacturers and researchers have made large strides in the health and comfort qualities of this optical technology since their introduction during the 1880s. These advances in comfort and health are the victories won by the hard work and creativity of numerous scientists, researchers and innovators. Independent optician's need an experienced and trustworthy contact lens manufacturer to offer quality products to their customers. For a lens manufacturer to work with you as a partner, eye care professionals should visit National Optical Co. online at http://www.nationalopticalco.com/.
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