What Are Polycarbonate Lenses? http://www.buyglasses.com Polycarbonate lenses are one of the lightest, thinnest and safest lenses on the market today. Most all lenses are now made from polycarbonate polymer. The polycarbonate material was developed in the 1970’s to be used for aerospace usage. Polycarbonate is still the preferred material used for space shuttle windshields and helmet visors of the astronauts. It wasn’t until 1980 when polycarbonate was introduced into eyeglass lenses because of the demand for lightweight and impact resistant lenses. The lenses typically considered ‘coke bottle bottoms’ are considered to be the past generations of lenses. One remedy to use this new material is because these lenses are typically thinner and lighter than most conventional glass or plastic and is the preferred choice in most eyewear. Previous lenses were made from a molding process where the liquid plastic was molded and baked for a long period of time. The liquid would harden and would eventually create the lens. Polycarbonate lenses on the other hand though start out as solid materials which are shaped like pellets. These are then heated until they melt. After the pellets have melted, the liquid is then inserted into the molds of the lenses which are compressed and cooled. Instead of this process taking multiple hours, the process to create polycarbonate lenses only takes minutes. This process is called Injection molding as opposed to the cast molding process. Another important feature of polycarbonate lenses is their ultraviolet light inhibiting value. With these lenses one doesn’t have to pay extra for UV treatment to protect eyes from potentially harmful rays. Nothing can compare to the impact resistance and safety of polycarbonate lenses. This material has been used in ‘bullet-proof’ windows in cars and airplane windshields. Because of the materials used, most safety glasses and children’s eyewear use ‘polycarb’ because of the incredible safety features. In fact, polycarbonate lenses are up to ten times more impact-resistant than typical plastic or glass lenses. Polycarbonate lenses are also used in rimless eyewear glasses because of the lightweight and due to the frame components. Polycarbonate lenses tend to be 10% thinner than the plastic or trivex plastic material lenses. The benefits of a polycarbonate lens far surpasses the older generations of lenses benefits. Polycarbonate lenses not only offer a lighter, more impact-resistance and UV protection, but it also offers a wider variety of lens designs. One now can use progressive and multifocal lenses on polycarbonates.