How To Tell If Sunglasses Are Polarized

Polarization is a practical and very helpful feature of sunglasses. It diminishes the glare from the sunlight that normally reflects on water or glass surfaces. And with a pair of polarized sunglasses, whether they have or don’t have UV protection, you should feel more comfortable in bright environments.

When you’re around water, for boating or fishing, or driving on a highway with the sun up in the sky, you’re going to love your polarized sunglasses. Want to know if your lenses have this feature? As opposed to the UV filter, which requires a dedicated tool for measuring it at home, polarization is much easier to verify.

Here’s how to tell if your sunglasses are polarized or not:

You will need a pair of sunglasses of which you already know for sure that it’s polarized. Take that pair and open up its arms, to free up the lenses. Then, grab the pair of sunglasses you want to check. Place one of its lenses on top of one of the polarized lenses, at a 90-degree angle. Basically, you want the two of them to sit on top of each other, perpendicularly.

The test will focus on the area where the polarized lens and the lens you’re testing will overlap. If you can see through that area, it means that the second pair is not polarized. If, on the contrary, the overlapping area turns black and there’s nothing you can see through it, you can know for a fact that your tested pair has, indeed, polarized lenses.

What if you don’t have polarized sunglasses for comparison?

So, the first method is simple, easy, and entertaining. However, the problem is that you can’t put it into practice if you don’t already have polarized sunglasses for comparison. Is there an alternative in such situations?

Luckily, there is. Chances are it will be even easier for you to try it, since it involves an LCD display. These days, anyone has an electronic display at hand. Whether from a smartphone, a camera, or a computer, even from the touchscreen of your car console, just pick one.

Then, put on your sunglasses, get in front of the electronic display, and slowly tilt your head. While you’re leaning towards a 90-degree direction, if your sunglasses are polarized, you should notice the image darkening to a point where it disappears.

Long story short, polarized lenses block electronic displays when viewed at a 90-degree angle from that screen. If the image remains the same while you tilt your head, they’re not polarized. It’s simply that easy and you can try it anywhere, at home or at the store. This trick will always work, because of how these electronic displays are designed. Try, and see for yourself!