When shopping for sunglasses, there are a lot of factors to consider. You want to look movie-star suave in your new shades, of course. You gotta be able to wear them in a wide range of scenarios. And, perhaps most importantly, they need to actually work—after all, sunglasses are often the first and only line of defense for one of the most important and vulnerable parts of our soft human bodies. You’re only ever going to get the one pair of peepers, so best treat them properly.
One word you’ll come across a lot, as you’re comparing brands and styles and UV protection, is “polarization.” But what, exactly, are polarized sunglasses? What are they for and why do they cost so much? We called up a few eyewear experts for a definitive answer.
What are polarized sunglasses and how do they work?
Simply put, polarized lenses filter light to reduce glare from surfaces like water, glass, asphalt, and metal. The result is a sharper, more vibrant visual experience. Colors appear richer, contrasts are heightened, and the world looks a little more like it does through an Instagram filter.
Without getting too deep into the physics of it, natural sunlight travels in waves oscillating in all directions, but when it reflects off a surface, those waves end up oriented in the same horizontal direction. Polarized lenses filter out just the horizontal waves, reducing glare and allowing for better vision in reflective environments.
It’s a pretty rudimentary technology that was discovered by the father of the Polaroid camera, Edwin H. Land, back in 1929, and brought mainstream shortly thereafter by eyewear juggernaut Ray-Ban and their Aviators. Designed specifically to help pilots see better at high altitudes, most modern sunglasses worn by pilots today are actually non-polarized, and if you’ve ever noticed your phone screen looking like a ’90s music video when you’re wearing polarized sunglasses, you know why. It’s science’s fault, of course. Polarized lenses block specific light waves, but so do digital screens, just not in the same way. Together, they compete in a visual tug-of-war that leaves you squinting at weird rainbows while texting. Stylish? Maybe. Functional? Not always.
Plus, as with most products presented with optional technology, polarized sunglasses often cost more than their non-polarized counterparts. Is it worth it?
Do you need polarized sunglasses?
According to Dr. Joseph Allen, a Virginia-based optometrist and one of the leading voices for eye health on Youtube, that depends. “The biggest benefit of polarized lenses is reduction in glare and light sensitivity,” he says. “There aren’t any direct health benefits of polarized lenses. But because of the reduction in glare and not seeing as many reflections off of the road, water, windshields, other objects, you can improve your visual clarity and potentially may reduce risks of things like motor vehicle accidents, which is handy, but not specifically a health benefit just from the polarization.”
