12/12/2016
WHY ARE GLASS LENSES BETTER THAN PLASTIC
BETTER OPTICAL QUALITY VISION
Mineral glass is created from natural elements like sand and soda ash. It’s endlessly recyclable and harmless to humans and animals alike. Its optical clarity, high resistance to scratching and lack of distortion make it the world’s best lens material.
The primary element in mineral glass is sand, or silica, a completely natural product. 90% of the earth’s crust is silicate. All of the Earth’s people, animals, plants, and bacteria amount to little more than a thin carbon-based layer on top of a pristine silicate planet.
Mineral glass lenses provide the most optically correct, distortion-free vision of any lens material in the world. Mineral glass lenses require no added layers or coatings during the manufacturing process. UV protection, scratch resistance, tint color, and moisture resistance are inherent properties of mineral glass. Mineral glass has a natural rigidity that ensures its shape is maintained. Unlike a plastic lens which flexes under stress, mineral glass will never flex and distort within the frame.
Mineral glass is also the most stable lens material in the world. It provides the most permanent tints that will not warp, peel, or fade over time. The inherent nature of glass makes it impenetrable to saltwater and oils. In fact, a molecule of oxygen will pass through a 1mm thick polycarbonate polymer in two weeks. The same oxygen molecule will take over a billion years to pass through 1mm of mineral glass. This is why mineral glass can create objects of great utility and beauty that endure for centuries, a time span in which plastics turn to dust.
BETTER SCRATCH RESISTANT
Mineral glass is the most scratch resistant lens material in the world. Throughout the development of plastic CR-39 lenses, scientists reviewed more than 2,000 patents in their quest for a suitable abrasion-resistant coating. None could compare to the natural characteristics inherent to glass. As a result, products from space shuttle windows to iPhones continue to use glass for its scratch resistant property.
The real secret behind the scratch resistance comes from the intense chemical and thermal hardening process each lens undergoes. The chemical process is called an ion exchange. An ion exchange involves exchanging larger ions from a molten chemical with the smaller ions on the surface of the glass lens. This process increases the amount of pressure a mineral glass lens can withstand. The thermal hardening process involves heating the lens to a softening point above 400 degrees Celsius, then cooling the lens surface rapidly while leaving the inside of the lens hot. This creates an additional hardening effect on the outside surface, further strengthening the lens.
