The Origin of Contact Lenses
There is much debate about who invented the concept of contact lenses but this is what we do know. Back in 1508 Leonardo da Vinci made sketches of a rough version of what a lens for the eye would look like. Then in 1632 Rene Descartes came up with the idea of a contact lens for the cornea. In 1801, building upon Descartes' earlier idea, a man named Thomas Young came up with a way to repair his own flawed vision using a glass tube filled with water and fashioned with a microscopic lens on the other end. Contact lenses were already beginning to take shape.During the years 1887 and 1888 more progress was made with contact lenses.
The first contact lenses to be made completely out of glass were invented by three men by the names of A. Eugen Fick, Edouard Kalt and August Muller. Although these lenses were a step in the right direction of progress, they tended to be anything but comfortable and corrected only a small amount of vision problems. The development of contact lenses made a huge step in the vision correction field when a new plastic called polymethylmethacrylate (abbreviated PMMA) appeared on the market. Following close on the heels of this new plastic, was a man named Kevin Touhy who applied for, and was approved for a patent in 1948 to make the very first ever plastic contact lenses.
These lenses proved a great deal more comfortable for contact lens wearers.The inventor most widely credited with the pioneering of contact lenses however is a chemist from Czechoslovakia by the name of Otto Wichterle in the year 1961. His soft lenses continue to be the number one choice for contact lens wearers throughout the world..
Timothy Gorman is a successful Webmaster and publisher of Vision-Doctor.com. He provides more contact lens tips and <a target="_new" href="http://www.vision-doctor.com/Discount-Contact-Lenses.html">discount contact lenses that you can research and purchase in your pajamas on his website.Free Contact Lenses
Contact lenses are a good substitute for bulky glasses that keep getting misplaced all the time. Even though there has been a dramatic evolution of newer, classier, and more stylish glasses frames, more and more patients are leaning towards using contacts lenses presently.
Contact lenses are expensive compared to regular glasses that are sometimes a onetime investment. Disposable contacts or even permanent contacts need to be changed either once day or a week or in matter of months. Also, they must be cleaned daily with solution and the eyes must be protected against dryness by using eye drops.
All these as a package are costlier than glasses.
Many hospitals and charity organizations arrange free eye check up campaigns where they give out free contact lenses instead of glasses. Some of them provide free check ups that are excluded from the lenses price. Also, some opticians give the offer of free lenses with a paid check up, which can help in reducing...
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Contact Lenses and Dry Eyes
Contact Lenses and Dry EyesBy
Until recently, contact lenses and dry eyes seemed to come hand in hand. Modern technology, however, has developed several ways for contact lens wearers to deal with dry eyes. When eyes become dry, they can be irritable, bloodshot and in severe cases, vision can become impaired. What Causes Dry Eyes?Dry eyes occur for a number of reasons, although there is thought to be a particular link between extended contact lenses and dry eyes. Dry eyes are also prevalent with older contact lens wearers as tear ducts become less effective with age.
Problems with contact lenses and dry eyes become exacerbated when wearers spend a considerable length of time in front of a computer screen or in an air-conditioned environment.Specific Contact Lenses for Dry EyesThere are some manufacturers that deal specifically with the problem of contact lenses and dry eyes. For example biomedics offer their own range of frequency 55 contact lenses for dry eyes. The higher...
Contact Lenses and Dry Eyes
Contact lenses > Contact Lenses and Dry Eyes
Contact Lenses in Silicone Hydrogel ? the Vision of the Future?
YEARS IN DEVELOPMENT
The concept of lenses made from silicone hydrogel was first proposed over 20 years ago. The potential benefits were clear but the technological challenge was as difficult as needing to combine oil and water to produce an optically clear product. Researcher organizations have to date invested considerable academic and financial resources to achieve the high performance soft lenses of today. They have done this quite simply because they see this material as the way forward and the ultimate standard of the future.
At the time of writing, silicone hydrogel lenses are available in the USA from four manufacturers: "Night & Day" and "O2OPTIX" from CIBA Vision, "Pure Vision" from Bausch & Lomb,
and "Acuvue OASYS" and "Advance" from J&J Vision Care.
OXYGEN TRANSPORT
So what's so special about silicone hydrogel as a lens material? Essentially, the great benefit of this material is it's ability to transport...
Contact lenses > Contact Lenses in Silicone Hydrogel ? the Vision of the Future?
Online Shopping: Choosing the Correct Contact Lenses
The online shopping experience is ? in many ways ? different from making the same purchases from a brick and mortar establishment. While the convenience of browsing, ordering and making shipping arrangements is hard to beat, health related products such as these must be designed specifically for the consumer who's doing the ordering. With this in mind, there are a number of things to consider when making the decision to buy this type of product via the internet.Your first step, if course, is to ensure that your prescription is up-to-date. This means that you should have had an eye exam within the last one to two years. In most cases, your contact lenses will be effective, as long as the prescription renewal date is still intact and hasn't expired.
Typically, these are valid for one to two years after your last exam, although some states allow the doctor to determine the expiration date.It's highly recommended that you only purchase contact lenses with a valid prescription that...
Online Shopping: Choosing the Correct Contact Lenses
Contact lenses > Online Shopping: Choosing the Correct Contact Lenses