Polycarbonate lenses are virtually unbreakable and are lighter and thinner than plastic. Because of this, polycarbonate lenses have been used for athletic glasses. Most opticians and doctors insist that eyeglasses for children be made with polycarbonate lenses. All are scratch coated and have UV protection in the material. Polycarbonate lenses also have a 1-year warranty for scratches. Polycarbonate lenses are difficult to tint and therefore should not be tinted more than 40% to avoid peeling. The index of refraction is 1.586 and approximately 10% thinner than CR-39.
Polycarbonate lenses may cause a blur in vision and cause color fringes (chromatic aberration) on cheaper quality lenses, especially in strong prescriptions. We strongly suggest purchasing high quality lenses from Essilor, Varilux and Kodak when purchasing polycarbonate lenses. Please Note: Solvents like nail polish remover or dry cleaning fluid can damage them.
The Benefits of Polycarbonate Lenses
Polycarbonate lenses have many benefits and are the recommended lens material for children because of, amongst other things, there incredible strength. Polycarbonate material was developed by the aerospace industry for use in the space program. It can also be found in police shields, airplane and bulletproof windows. It is ten times more impact resistant than other plastics and is so strong that is exceeds the FDA's resistance requirements by a factor of 40!
The great strength of polycarbonate lenses means that it is incredibly hard to break even in the roughest of situations polycarbonate sunglasses will not shatter.
Polycarbonate lenses are also highly scratch resistant. Due to a special anti-scratch coating which will keep the lenses clear for as long as possible, even in the most extreme situations.
Another benefit of polycarbonate lenses is the lighter weight, polycarbonate lenses are thinner than the usual glass or plastic lenses as well as the material itself being lighter than glass and plastic. This means the sunglasses themselves will be that bit lighter, adding to overall comfort.
A great benefit of polycarbonate lenses is that they offer inherent ultraviolet (UV) radiation protection, cutting out around 99% of these potentially damaging rays - it doesn't matter whether the rays are from direct sunlight, computer screen or indoor lighting.