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Features of polycarbonate lenses

Since its creation in 1970s, polycarbonate has been widely used in aerospace applications, helmet visors of astronauts and space shuttle windshields. Today, this material has been the standard for safety glasses, sports glasses and children’s eyeglasses. Polycarbonate lenses are thinner, lighter and 10 times more impact-resistant than traditional plastic lenses.

Polycarbonate lenses are made in a way that is quite different from that of regular plastic lenses. Conventional plastic lenses are made from a cast molding process. The production of a polycarbonate lens uses an injection molding process, during which small pellets will be heated into liquid polycarbonate. Further steps include liquid polycarbonate injection and high-pressure compression. Another lens material that also has similar features of polycarbonate is Trivex. Using cast-molded manner, Trivex lenses provide crisper vision and have become a major rival of polycarbonate lenses.

Polycarbonate lenses also feature 100% UV protection resistance, without the help from UV treatment. While polycarbonate lenses are extremely impact resistant, it is also relatively soft, which means they can absorb energy. This feature of the material makes polycarbonate lenses fragile to scratches. As a result, scratch-resistant coatings are needed for polycarbonate lenses to provide necessary scratch protection. These scratch-resistant coatings enhance the hardness of polycarbonate lenses.

Another precious property of polycarbonate lenses is that they are not brittle. Even attacked by speeding objects such as balls or racquets, polycarbonate lenses will not break due to their ability to hold up under impact. When it comes to regular plastic lenses, fast-moving objects can easily broke the lens and hurt the eye. Thanks to this protective feature, polycarbonate lenses have become the first choice for children’s eyeglasses, sports goggles and safety glasses.

During dangerous sports, impact-resistant frames are also necessary to match polycarbonate lenses, since the frames are still essential to hold the lenses. Simple polycarbonate lenses can not provide enough resistance against high impact. In this case, polycarbonate lenses on ordinary frames are not safe. Actually, polycarbonate lenses are recommended for all types of children’s eyeglasses.

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