When it comes to buying sunglasses, most people understand that polarization needs prioritization: wraparound polarized sunglasses can help drivers, golfers, fishermen, boaters, and other athletes see their surroundings safely and more clearly. Polarized lenses (ever-popular today) take their name from the Polaroid over 80 years ago, when Edwin H. Land began experimenting with making lenses with his patented Polaroid filter. If you've recently purchased a pair of unbreakable sunglasses with indestructible frames and can't recall whether or not they're polarized, Lifehacker has a cool trick to help you out. Let's look:
GET TWO PAIRS OF SUNGLASSES.
The first step is easy enough -- just grab a second pair of sunglasses (or borrow some from a friend) so that you can determine whether the pair in question is, in fact, polarized.
HOLD THE TWO PAIRS AT A 90-DEGREE ANGLE.
Now -- hold both pairs of sunglasses so that you can see through them both. Turn the first pair slowly at a 90-degree angle; if your vision through the second pair of lenses gets noticeably darker, they're polarized. If not, they're simply normal sunglasses. There's also a way to do this using the screen of your smartphone: "You could also do this trick with most LCD smartphone screens. Just look at your phone in portrait orientation, then slowly turn it to landscape to see if you notice any change. If you can though, try to test this with a pair of glasses that you know are polarized beforehand, since not every phone screen behaves the same way," writes Shep McAllister. This trick really comes in handy at mall kiosks and other high-end sunglasses retailers where you feel you need to ensure authenticity. But it's a pretty cool trick to know anyway. In 2012, 95.9 million units of Plano sunglasses were sold in the United States. Plano (polarized, non-polarized) pertains to eyeglasses that do not contain a curvature for correcting vision defects. Whichever type of sunglasses you need, it's best to prioritize polarization and consider investing in indestructible frames. For more information about polarized sunglasses with indestructible frames, check out REKS.com