Are Your Shades Polarized? Here's How to Check...

Still struggling with intense sunlight, even with your shades on? It’s time to go polarized. Making the switch is easy if you’re unboxing a new pair. Just look on the label. If you’ve found an older pair in the house, however, and want to know whether it’s ready for anything the outdoors can throw at it, here’s how to check if it’s good to go.

How Do Polarized Sunglasses Work?

The science behind polarized sunglasses is as complex as it is impressive. Light waves will scatter in any direction, but when light is reflected off a flat or polished surface, the waves will concentrate in a single horizontal direction, creating a harsh glare or flashes. Polarized shades have a special chemical coating that filters out brilliant horizontal light waves but allows softer vertical waves to pass.

The Benefits of Polarized Lenses

Sunglasses with standard tinted lenses will reduce strain on the eyes and improve visibility in most conditions. They’re fine for benign conditions with moderate sunlight. But in some cases, you need something more specialized. Glare can become overwhelming on a sunny day if you’re around water, windows, or flat, reflective surfaces such as highways. Slip on a pair of polarized lenses and you’ll notice how bright, shimmering, or scintillating light sources lose their intensity. Suddenly, you can see beneath the water’s surface or through windows, pick out the contours of waves, and generally stop squinting for a comfortable view.

How to Tell If Your Sunglasses Are Polarized

If you want to check that your shades will do what you want them to, there are three easy ways to identify polarized glasses—no sticker, label, or box required. Try one of these simple tricks.

1. If You Have Only One Pair
Look at a bright, reflective light source (e.g., glass, water, or polished metal) with your shades on. If the light increases in intensity when you tilt your head sideways to around 60 degrees, you’re wearing polarized sunglasses. If there’s no change in quality, they’re just tinted.

2. If You Have Two Pairs
Already have a pair of polarized glasses and want to check if your new pair is polarized too? Just hold one pair in front of the other. You should be able to see through both lenses. Now rotate one pair to a right angle. If the lenses blend to black, the secret is out: You’ve got two pairs of polarized shades.

3. Using a Digital Display
Look through your shades at an LED or LCD display, such as a laptop, tablet, cell phone, or GPS. The display will be dim to begin with, but if it goes black when you tilt your head, that’s proof of polarized lenses doing their magic.

Common Myths about Polarized Sunglasses

Now you know when you’re wearing polarized shades. How about the view from the other side? You might be surprised to know that polarized lenses do not look any darker than standard tinted shades when in the box or on the rack. But that’s not the only misconception:

• From blue to fuchsia, polarized lenses come in many colors. You can choose any color you want and the performance will be the same.
• Whether it be aviators or classic shades, any style can be polarized. It’s all about the lenses, not the frame.
• Polarized sunglasses are by no means a “luxury item”. You can get a pair for $38. There might have been a time when polarized lenses were exclusively for aviators and astronauts, but they’re almost standard now.

Who Needs Polarized Lenses?

Because they reduce overall strain on the eyes, polarized sunglasses are great for anyone who spends a significant amount of time outdoors. They're especially helpful, though, for certain activities like boating, fishing, biking, and running.

Boaters wear polarized shades to filter out glares from the waves, allowing them to read the patterns of wind shifts more clearly as they move across the water’s surface. Anglers find they lend an advantage in seeing fish beneath the water’s surface, either at sea or on a lake. Harsh sunlight isn’t always the problem when tracking fish. Polarized lenses also cut through the reflection of trees or clouds on the surface. Bikers, runners, and drivers often prefer polarized sunglasses for comfort on longer journeys as the lenses soften the effects of sunlight shimmering on the road surface.

When Standard Tinted Shades Will Do

In some conditions, wearing polarized sunglasses might leave you a little overpowered. If the sunlight conditions are overcast or subdued, the effects will be negligible compared to tinted shades. Some wearers will even find that polarized sunglasses impair visibility when reading backlit digital displays. This could be a distraction when you’re trying to check your GPS or speed meter on a hike or a bike ride. For the same reason, pilots avoid wearing polarized sunglasses in order to have a full view of the instrument panel. Polarized shades are also not recommended for skiers as it makes it difficult to accurately gauge potential hazards or icy patches.

A pair of polarized shades can massively improve the comfort and experience of a day out on the water or a long day in the sunshine. Before you go, run through our checks to confirm that your sunglasses are, in fact, up to the challenge.

Written by Nick Marshall for Knockaround