By Jody Johnson-Petit
It’s a bright, sunny day, but you don’t have your sunglasses on hand.
Not to worry. Thanks to technology, your prescription lenses can help protect your eyes from changing light conditions and ultra-violet rays.
Photochromic lenses are optical lenses that darken on exposure to specific types of light of sufficient intensity, most commonly ultraviolet light. Since they react to UV light, the lenses fade back to their clear state indoors.
“The main benefits of photochromic lenses are convenience,” says Rick Leroux, director, marketing and communications (Lenses) for Centennial Optical. “Automatically adjusting to changing light conditions so that the wearer does not have to switch their eyewear when going between indoor and outdoor.”
Photochromic lenses also safeguard your eyes.
“Full protection against the harmful effects of invisible ultra-violet rays in bright sunlight, as well as filtering some high energy visible (HEV) light, both indoors and outdoors,” says Leroux.
However, these lenses are not to replace the use of sunglasses.
“I want to emphasize that Transitions lenses are meant to be a replacement for ordinary clear prescription lenses – not sunglasses,” says Patience Cook, director, North America marketing, Transitions Optical. “Transitions lenses are an enhancement over ordinary clear lenses, because they help your eyes adjust to changing light better than they would on their own or with clear lenses.”
Our eyes are working all day, attempting to adjust to varying light conditions.
Photochromic lenses are a great solution for UV protection when sunglasses cannot be worn.
“Polarized prescription sunglasses are a great second pair, especially for driving, but for someone who regularly works both in and out-of-doors for example, it is not always convenient to have to carry an extra pair of glasses with you everywhere you go,” says Leroux.
Centennial Optical offers both PhotoViews from Signet-Armorlite, and their house brand Centoptic SunChangers lenses.
PhotoViews grey and brown photochromic lenses are available in single vision, bifocals, and both conventional and digitally customized progressive lens designs. Centoptic SunChangers provide rapid photochromic activation and fade back, going from clear indoors to darkening to 70 percent tint within sixty seconds.
Transitions, meanwhile, offers Transitions Signature VII lenses, which are ideal for clear vision indoors with the fastest fade-back speed.
Transitions XTRActive provide extra protection from light, even in the car. They are extra dark outdoors to protect from the brightest sun, with a hint of tint indoors to help protect from harsh lighting.
Transitions Vantage lenses provide extra glare reduction outdoors and have variable polarization for crisper, sharper outdoor vision.
Photochromic technology has improved over the years to ensure the lenses begin to darken immediately upon exposure to UV light, and start to fade back to clear as soon as the rays are no longer present.
“With Transitions Signature lenses, most of the fade-back occurs in the first five minutes,” says Cook. “Transitions lenses are not the same as they were five years ago. The newest Transitions Signature lenses with Chromea7 technology allows the lenses to fade back twice as fast as the previous generation.”
“Anyone who wears glasses or sunglasses (prescription or not) can wear Transitions lenses – there are options for every lifestyle, every age, and a number of different sports and activities,” says Cook.