Decided to go for some contact lenses? Good for you, but before starting to wear them you simply must know something about these wonderful inventions.
The history of contact lenses started in 1500 when Leonardo Da Vinci brought into discussion the concept of contact lenses. Much later, in 1823 a British astronomer discovered that eyesight could be adjusted by wearing lenses applied directly to the cornea. The history of contact lenses evolved from William Fienbloom who created, in 1939, the first contact lens from harsh plastic. It was applied to the eye with some kind of glue. In 1971, soft contact lenses were invented and, in 1979, the permeable contact lenses first appeared. It was in 1983 that the detachable contact lens revolutionized the market. They were invented by a Danish producer who sold his copyrights to Johnson&Johnson. The Company started selling contact lenses on a large scale in 1987. They soon become very popular and remained so until today.
Being a little familiar with the history of the contact lens is not enough. The most important details refer to the situations when it is advisable to wear contact lenses:
– To correct myopia, hyperopia, presbyopia, and astigmatism. The most important advantage of contact lenses is that they can correct anisometropia. A person is diagnosed with it when the eyes do not have the same distance point refraction. Even when there are differences over 3 dioptrics between the eyes, the correction cannot be done by wearing eyeglasses.
– For therapeutic purposes – as a substitute for the bandage, after surgical intervention.
– For esthetic and cosmetic purposes.
There are a few steps that need to be followed when you decide to go for contact lenses:
-First of all, medical consultation takes about an hour to complete. There are a few things that need to be taken into consideration: the reasons you decided to wear contact lenses instead of glasses and whether you can afford them or not.
-The next step is an exam that you’ll have to take, an exam called “refractometry”. Contact lenses are prescribed together with the spare eyeglasses. Another series of medical exams will follow after this one.
-The distance and diameter of each contact lens have to be carefully measured (Keratometry).
-The testing of the contact lens (which varies from 5 to 30 minutes) is necessary for the individual establishment of the curvature and of the diameter of the contact lens.
-The last step is the periodical exam which varies depending on the type of contact lens.
Nowadays, we benefit from a large variety of contact lenses so you should have no problems choosing the right ones for you. There are:
-PMMA contact lenses – this type was the first one and it was made in 1960. The contact lens is made from very durable plastic, polymethyl methacrylate. The disadvantage consists in the fact that it doesn’t allow oxygen in the air to reach the cornea. Instead, when you blink, the oxygen from your tears reaches the cornea. This type of contact lens is preferred for its durability and low cost.
-Gas-permeable lenses – RGPs – allow oxygen in the air to go directly to the cornea. They are made of plastic in combination with silicone and fluoropolymers.
– Soft contact lenses made of plastic that incorporate water have as main attributes flexibility and softness and they allow oxygen to reach the cornea.
-Among the most popular types of disposable lenses are the Acuvue contact lenses. The Acuvue contact lenses are designed for people with little or no astigmatism and should be replaced every two weeks. Some Acuvue contact lenses are approved not only for everyday use but for overnight wear too. The advanced version of the Acuvue contact lenses is made of materials that allow oxygen to pass in even greater amounts than the other types of contact lenses.
Depending on the number of times the contact lenses will be worn, they can be divided into:
– Long term lenses that can be used for up to one year, but not continuously and
– Short term lenses made only for a one time wear. They can be useful for one day and one night, but afterward, they have to be thrown away.
Nowadays, more and more people change their eyeglasses for contact lenses because the latter is more comfortable and esthetical. People can wear them in almost every situation: when practicing sports, at work, in front of the computer, at the beach, when swimming, etc. Not only do they make you healthier, but they can give you the eye color you always wanted.
The contact lens is another proof of how far weve come: we have the power to change our own eye color. If you want to find out more information about Acuvue contact lenses, please you can visit this site.
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