Sunglasses are powerful accessories. They protect your eyes from harmful UV rays, make you look the perfect amount of cool, and can even correct your vision just as well as regular prescription glasses.
Given the choice between polarized and non-polarized sunglasses, however, you might not know what to pick—or even what “polarized” means.
What Does “Polarized” Mean When We’re Talking About Sunglasses?
Polarized sunglasses have a special coating on their lenses that’s especially good at blocking out glare. When you’re wearing them, you might notice that colors and details appear sharper than when you wear “normal” sunglasses.
What Do Polarized Lenses Do?
The key function of polarized lenses in sunglasses is to reduce glare from the sun. But they can also make colors appear more vibrant, increase contrast, and even reduce the symptoms of eye strain.
They’re especially useful if you spend a substantial amount of time outdoors, as you probably want to avoid glare while getting the best view of the scenery.
How Do Polarized Sunglasses Work?
Polarized sunglasses reduce glare with lenses that are coated in a chemical filter. The filter works like the vertical slats of a fence or very tightly packed bars on a window: It won’t allow anything long and horizontal through its gaps. So, when the horizontal wavelengths of glare try to pass through, they can’t reach your eyes.
Hard to picture? Let’s take a closer look at glare.
Most of the time, light scatters in lots of different directions after it hits the various sides and angles of an object. But if the object is flat—like a metal sheet, or the calm surface of a lake—light bounces off in a single, concentrated direction, creating the super-bright effect known as glare.
These light waves are also polarized, which means they’re mostly aligned one way—in this case, horizontally. Luckily, your sunglasses will only permit vertically polarized light past their lenses. That chemical filter absorbs everything else.
Negating glare with polarized sunglasses is both convenient and safe. Glare can cause discomfort and pain in your eyes, which can lead to headaches, migraines, and even car accidents.
Who Invented Polarized Sunglasses?
Some people claim that polarized lenses were first engineered in the 1980s by scientists at NASA’s Jet Propulsion Laboratory. Inspired by the light-filtering oil found in the eyes of birds of prey, they created a new kind of sunglasses lens that could guard against bright, distracting light.
However, this story is only half-true. Although these scientists did indeed create a type of polarized lens, they weren’t the first to do so. Credit for that goes to Edwin H. Land, a physicist who’s best known as the inventor of the Polaroid camera.
Before he switched his focus to cameras and film, Land used his groundbreaking Polaroid material to make and market polarized sunglasses as early as 1936.
What’s the Difference Between Polarized and Non-Polarized Sunglasses?
With polarized sunglasses, you won’t be subjected to glare and its more irritating (or even dangerous) effects. Your vision will likely have more clarity and contrast than if you were wearing non-polarized lenses.
Non-polarized sunglasses lack the glare-filtering coating that polarized sunglasses have. Our non-polarized lenses protect against harmful UV rays at the same capacity as our polarized ones, but they do not reduce the same amount of glare.
Finally, polarized sunglasses are often priced slightly higher than non-polarized sunglasses.
How Can You Tell if Sunglasses are Polarized?
If you aren’t sure whether your sunglasses are polarized, you can find out by trying a few different methods.
1. Hold them up to another polarized surface. Where polarized lenses overlap at opposing angles, they create an almost pitch-black surface. You’ll need to find another polarized material, whether it’s a second pair of sunglasses at the drugstore or a computer screen with an anti-glare feature.
Look through your sunglasses and then tilt them 60 to 90 degrees. If the lenses shift to black, then you’ll know they’re polarized.
2. Test them out on a reflective surface. Find a highly reflective surface, like a metal table or countertop. Look through the sunglasses and tilt them about 60 degrees. If they’re polarized, any glare that’s present on the surface should be further reduced.
3. Look at an LCD screen. Polarized lenses can make LCD screens appear very dark. If you find it hard to discern what’s on an LCD screen when looking through your sunglasses, then they’re probably polarized.
Our 5 Most Popular Frames for Polarized Lenses
Polarized vs. Non-Polarized Lenses: Which Should You Choose?
When you’re looking for sun protection, the choice between polarized and non-polarized sunglasses often depends on what activities you’ll be doing, what time of day it is, and your personal preferences.
Often, polarized sunglasses win out because they offer so many vision benefits—but they’re not meant for every situation.
Advantages of Polarized Lenses
Reduced glare and enhanced vision outdoors: Polarized sunglasses are wonderful to have when you’re spending a lot of time outside, whether you’re hiking, picnicking, or boating. Their tendency to make colors vibrant means that greens will look greener and the sky will look even more blue when compared to non-polarized sunglasses. Areas of shadow will contrast more starkly with areas of light, and you’ll be able to pick up on fine details even though the world has taken on a slightly darker tint.
When you wear polarized sunglasses around water, the benefits are twofold: You won’t experience glare, and you can actually see into the water (if it’s clear enough). People who fish as a hobby often own polarized sunglasses for this reason.
Mountain bikers, golfers, and runners might also enjoy wearing polarized sunglasses, because they won’t have to worry about glare interfering with their performance.
Lastly, polarized lenses are often well suited for snowy conditions, which can otherwise irritate your eyes with its brightness and harsh reflections. However, polarized lenses are not recommended for use while skiing or snowboarding, as they may make it harder to distinguish between fresh snow and glare-producing ice.
Safer daytime driving: The road is an environment ripe for glare. Light can reflect off of car hoods, bumpers, and even the road itself (not to mention the brightness of oncoming headlights). Wearing polarized sunglasses while driving during the day can mitigate this glare and make for safer, less distracted driving.
Less eye strain, more comfort: Reduced glare means a lower risk of eye strain and its irritating symptoms. Polarized lenses can also be a source of relief for people with light sensitivity, and they’re often recommended to patients who have had cataract surgery.
To sum up, it’s advantageous to wear polarized sunglasses when …
- You’re spending time outdoors during the day
- You’re fishing or boating
- You’re playing outdoor sports and don’t want to be distracted by glare
- You’re in the snow (but not skiing or snowboarding)
- You’re driving during the day
- You’re sensitive to light
Disadvantages of Polarized Lenses
Reduced clarity when looking at instrument panels and LCD screens: Although polarized lenses can make life easier in many respects, they aren’t the best choice for anyone who needs to look at certain screen displays for work.
For example, most pilots shouldn’t wear polarized sunglasses while flying, as they can make the plane’s instrument panels more difficult to see. Certain pieces of heavy machinery have similar controls and should not be operated by anyone wearing polarized lenses.
The lenses might also affect your view of computer screens, ATM screens, and the screens at gas station pumps. It’s a good idea to test your polarized sunglasses with various screens to see how they can impact your vision.
More difficulty seeing patches of ice, especially in low-light conditions: In some scenarios, you might want to be able to see the glare reflecting from patches of ice—knowing where the ice is can help you avoid it!
If you’re downhill skiing or snowboarding and don’t want to slip, or if you’re driving where there might be lots of black ice, then you may want to leave your polarized sunglasses at home.
Additionally, because they’re so good at blocking out harsh light, polarized lenses can make dark environments even darker. For this reason, you shouldn’t wear them while driving at night.
In conclusion, you might want to wear non-polarized sunglasses when …
- You need to look at LCD screens or instrument panels often
- You want to be aware of glare, whether you’re trying to spot ice or see in the dark
- You’re just not a fan of the visual effects caused by polarized lenses
Are Polarized Sunglasses Better for Your Eyes?
Polarized sunglasses offer a lot of vision benefits, especially for outdoorsy types. They can shield you from glare and eye strain, enhance your view of the world, and even make certain activities safer.
But they aren’t innately better or healthier for your eyes than non-polarized lenses—it all hinges on how you use them. Knowing the difference between polarized and non-polarized sunglasses should help you make the right call for you.
Our final tip: no matter what type of sunglasses you decide to buy, make sure they have built-in UV protection and frames that make you feel stunning.