What is a photochromic lens?
Invented in the 1960s by Corning Glass Works Inc, a photochromic lense is a lens that changes color when exposed to light. The term photochromic comes from the combination of the Greek word roots for light, photo, and color, chroma. More commonly, photochromic lenses transition from clear to tinted when exposed to sunlight, effectively allowing a single pair of eyewear to function as both your sunglasses and eyeglasses! Not only do these types of lenses help to reduce glare from the sun, they also provide 100 % UV-protection for your eyes regardless of tint whether their tinted or not. Other common names for photochromic lenses include Transitions (a popular brand name), variable tint, and light adaptive lenses.
So what is a photochromic lens good for? Well for starters, since they adapt their tint based on how bright it is outside, glasses with variable tint lenses are ideal for (but certainly not limited to!) people who wear both glasses and sunglasses, and frequently go inside and outside. One of the main advantages of combining the two into one saves you from having to carry around two sets of glasses everywhere. That means no more trying to fit bulky glasses cases in your pocket or trying to remember the last place you stored your shades.
Deep End, in Tortoise
Fun fact: Photochromic lenses can also help your glasses frames last longer! When people do the glasses/sunglasses combo, they end up handling their glasses more frequently since they need to change them when they switch from indoors doors, which can cause more wear and tear on the frame. But if you wear glasses with Transitions, or any other type of light adaptive lenses, you don’t need to change your eyeglasses or sunglasses every single time you go inside or out— they automatically change when you need them to! Keep in mind though, you may want to store a pair of sunglasses in your car. Why’s that? Well, in order to help protect you from UV rays while driving, most automobile windshields are made to block that same UV light that makes your adaptive lenses darken. To guarantee that your sunny drives are glare-free, you may need a pair of sunglasses.
Now at this point, you’re probably wondering what is a photochromic lens made of in order to make it turn from clear glasses into sunglasses. As much as we’d like to say it’s magic, it’s not. While glasses lenses used to be made from actual glass back in the day, almost all modern lenses, like Transitions, are made for polycarbonate or other types of ultra-durable plastic polymers. To continue with a bit more of lens history, photochromic glass lenses were originally infused small amounts of silver. When exposed to UV rays, these bits of silver become opaque. While normally having opaque sunglasses lenses was a bad thing, the small amount of silver actually used in the lens is so little, they only have a translucent tint instead of becoming impossible to see through. Nowadays, plastic lenses contain little molecules actually change shape when exposed to UV light, causing them to darken.
What is a photochromic lens like versus a transition lens?
Well, they’re essentially the same thing, with Transitions being a specific brand of photochromic lens that is produced by lens manufacturer, Essilor. But while they both achieve the same effect, Transitions offer a more premium lens experience. They change from between tinted and clear more quickly and have less of a hint of tint than basic light adaptive lenses. On top of that, Transitions also fit a wider range of prescriptions than basic variable tint lenses. And don’t worry if you have progressive lenses! From single vision to multifocal, there are light adaptive lens options for almost any prescription. At EyeBuyDirect, we offer two tint option:s a vintage brown and a classic, dark gray.
So what are you waiting for? Live the good light and enjoy life more comfortably with lenses that adapt to your needs. On our eyeglasses catalog, any frame you pick can be customized with photochromic lenses! All you need to do is make sure to pick LIGHT ADJUSTING during your lens selection and choose the option fits you best!