What Does Scratch-Resistant Mean?
By Essilor News
The day you get a new pair of glasses, you promise yourself you'll take care of them this time. Unlike your old, scratched-up and bent pair, you'll place these gently in their case and wipe only with the cloth provided. Fast forward a few months, and you likely find yourself scrounging for your glasses in your desk drawer or leaving them on your dashboard (a big problem!)
But surprisingly, after you catch yourself treating them like a dirty napkin for the tenth time, you notice that the lenses still give you a sharp view and are miraculously free of major scratches. Chalk your good fortune up to one of the modern marvels of life in the 21st century:scratch-resistant lenses. Before 1972, your glasses would've been fairly free of scratches because the lenses were most likely made of actual glass. Ground and polished glass is very resilient and doesn't allow many marks and scuffs, but it's heavier and more prone to shattering.
In 1971, the Food and Drug Administration published a new policy that stated that all prescription lenses must be impact-resistant by February of 1972. Manufacturers starting switching over to polycarbonate, or plastic, lenses, which were more durable, less expensive and lightweight, but also easily picked up scratches.
The first success at creating a more durable plastic lens came from Ted Wydeven, Ph.D., a NASA scientist who was working on a water-purification system for spacecraft. He discovered that electricity could induce an organic vapor to coat plastic with a thin, durable film. NASA then used this process to make helmet visors and other aerospace equipment tough enough to stand up to the rigors of spaceflight. The brand Foster Grant, who had been searching for a scratch-resistant coating for years, licensed the technology in 1983 and soon the know-how spread throughout the industry.
Today, scratch-resistant lenses are pretty much an industry standard, but you will still want to specify that you want your lenses treated with a scratch-resistant coating when you are talking to your optician. And remember that the clear coating applied to the lenses makes the surface much harder-up to 10 times harder than uncoated-but won't eliminate all scratches. Crizal No-Glare lenses provide excellent resistance from scratches, protection against daily abuse, plus toughness for long wearing use.
And remember, taking care of your glasses properly is the best protection against scratches.