What Are Polarized Sunglasses—And Why Should You Care?

Sunglasses are perhaps the most effortless, versatile accessory on the market. Slip on the right pair and you can take your look from basic to bad-ass in an instant. You can change things up just as easily by mixing and matching colors, lenses, and frames, providing endless options whether you’re chasing surf or chilling with friends at happy hour.

But while sunglasses have an undeniable fashion element, it’s important to remember that their main function is providing critical sun protection for your precious peepers. And knowing a little bit more about the science behind how and why they work can help you make important decisions when purchasing a new pair. One of the biggest choices comes down to the lens: Do you want polarized or non-polarized lenses?

You’ll quickly notice the price difference. Polarized lenses will cost more than their non-polarized counterpart. But what are you getting for the extra cash? Is it worth it? Understanding the basics of polarized lenses—what they are, how they work, and the benefits of wearing them—can help you pick out just the right pair when it’s time to shop for new shades.

What are Polarized Lenses?

First, a quick refresher on light and how it travels (cue junior high science classes). When it moves, light is scattered in all directions. But when it bounces off flat or shiny surfaces, that scattering is reduced. That’s because the light waves are moving in a single plane. This means the light is traveling in a more highly concentrated direction, sometimes becoming so bright it has an adverse effect on visibility around the area of glare. This kind of light is called polarized light, hence the term “polarized sunglasses”, which have polarized lenses that are designed to reduce the impact of the polarized light.

It is also important to know the difference between UV protection—which is protection against potentially dangerous ultraviolet, or UV light—and polarized lenses. UV-protection lenses will typically have a label listing the level of protection they offer, but they are not necessarily polarized and will not do much to reduce glare. UV protection is important though, so take that into consideration when making your purchase, though most polarized lenses will also have UV protection.

How do Polarized Lenses Work?

Essentially, polarized lenses help reduce glare by allowing only vertically polarized light to enter the lens. They have a special filter that helps block intense, reflected light. The molecules of this filter are lined up precisely to block a portion of the light traveling through the lens, allowing greater clarity and easing eye strain.

How Do Polarized Sunglasses Affect What You See?

Since your eyes don’t have to work as hard in bright conditions, it’s easier to see what’s around the object from which the glare is emanating. They will let you cut through the glare on the surface of water to better see underneath, and also create greater contrast for objects or areas that would otherwise be difficult to see due to glare. So it basically means that you’ll be able to enjoy outdoor adventures like boating or fishing way more.

That being said, polarized lenses can make it difficult to see LCD or LED screens, such as ATM screens, GPS units, or some cell phone screens.

Who Will Want to Wear Polarized Lenses?

Polarized lenses can benefit anyone who wants to reduce glare during activities or travel in bright conditions. One of the most useful places to wear polarized sunglasses is on the water, during outdoor activities like fishing, boating, or just relaxing on the beach. Polarized lenses reduce glare and reflection from the water, allowing greater clarity of vision and ability to see more detail beneath the surface—which, as anglers can attest, is extremely important for spotting the shadows of that trophy fish as it cruises alongside your kayak.

Wearing polarized sunglasses while driving also can be beneficial, as they can help eliminate the effect of glare on the road or from the hood of a car, or in other situations where visibility can be limited by bright lights and reflections from flat or shiny surfaces.

On top of helping reduce glare, polarized lenses can help ease the strain on your eyes from too much time in bright sunlight. If you find yourself suffering from frequent headaches, eye strain might be one of the causes, and polarized lenses can offer a solution for those with a sensitivity to light, as well as people who have had cataract surgery.

Who Should Avoid Wearing Polarized Lenses?

While it might seem that wearing polarized sunglasses is an all-around no-brainer, there are some instances where it’s actually safer to be able to see the glare off of flat or shiny objects. Downhill skiing is a prime example—wearing polarized lenses makes it difficult for skiers to accurately gauge potential hazards or icy patches, as the lenses reduce glare and make it more challenging to assess the terrain. So if you’re planning to hit the slopes, leave your polarized pair at home.

It’s also important to note that many polarized lenses come in a darker tint, which may impact depth perception and can be hazardous during high-speed sports such as cycling or mountain biking, where quick reactions to terrain changes are paramount to safety.

Ready to Rock a Pair of Polarized Sunglasses?

Once you’re schooled in what they’re all about, it’s time for the fun part: Picking out a pair of polarized sunglasses that are perfect for you. Knockaround offers dozens of options in different styles and color variations—with both polarized and non-polarized options. There’s something for everyone, so grab a pair (or two) and enjoy healthier eyes while taking your outdoor adventure game to a new level—and looking good while you’re at it.

Written by Jeff Banowetz for Knockaround