After centuries of evolution, modern eyewear is much more comfortable and functional than those early ones. In early days, glass produced by factories often had bubbles and other imperfections. Currently, the techniques of glass production have improved significantly and glass has become indispensable for eyeglass lenses.
Anyone buying sunglasses today can be easily confused by the vast variety of lens choices and materials like Trident, ACR , Competivision, Carbo-Glass and the list goes on and on….
The bottom line is there are basically 3 lens material choices. Glass, Plastics and Laminate. Each with its own features or benefits.
Glass – Glass lenses are still the most optically stable material for lens construction. Glass use in lenses has been reduced dramatically as the material of choice because of and its vulnerability to breakage when hit or dropped. Many people are also avoiding it now because of its weight.
Polycarbonate (better know as plastic) – Today 98% of regular and prescription sunglass lenses are usually made from polycarbonate, high-index, and CR-39, all common trade names for plastic lens material. With its ability to be easily molded into endless shapes, combined with its resistance to damage or scratches and lightweight, plastic lenses are here to stay!
Laminated – Although less common laminated lenses are combinations of glass and/or plastic to achieve a specific performance or looks.
All the above lens materials can be modified by adding chemicals or materials to provide different protection or added performance features. Here is a short list of available lens add-ons or upgrades.
o Polarization
o UVA / UVB Protection
o Mirrored
o High Contrast
o Scratch Resistance
o Photochromatic
o Prescriptions
So no matter what fancy name manufactures dream up for their lens product the basic facts are they will be one of these materials, Glass, Plastic or Laminate. Hopefully this will help you when buying your next modern eyewear sunglasses.
