How to Tell If Sunglasses Are Polarized
Ian Fortey Updated on March 15, 2022. In Beachby
When you’re heading out on the water, you want to make sure you have a good pair of polarized sunglasses. Wearing polarized glasses on the water, either while boating or fish, is important. They’re more than just a cool lying pair of shades. A good pair of polarized sunglasses offers UV protection. They reduce the glare from light off of water, pavement, and glass.
What Does Polarized Mean?
Polarized sunglasses are treated with a chemical. This will either be applied as a coating or embedded in the glass. The result is a significant reduction in glare.
We see things because light bounces off of them. The light that bounces off of any given object allows us to see that object clearly. When the sun is bright, the light bounces off of every surface it touches. It’s worse with highly reflective surfaces like the open water. The light scatters everywhere and makes it hard for us to see.
The coating on polarized sunglasses is the key. It is able to absorb those horizontal light rays that bounce off of the surface of the water. Vertical rays can still pass through, but the glare of reflected light is eliminated.
Why Do Polarized Glasses Matter?
There is more to polarized glasses than just a cool-looking pair of Ray Bans. The glare reduction caused by polarized lenses reduces eye strain. It also improves your ability to clearly see what’s ahead of you. That’s why polarized lenses are ideal for truckers, boaters, and anglers. When you need to see clearly but are faced with a reflective surface, they are ideal.
Serious eye strain caused by glare can lead to accidents. It’s easy to miss things hidden in glare. It effectively creates a blind spot right in front of you. On calm waters, if the sun is bright enough, you’ll experience a white spot. This can be so big an entire boat can disappear right in front of you.
Also, glare leads to that after burn effect. Even when you turn away from the light, your eyes need time to adjust. The glare image will be seared into your vision briefly. That may not be a big deal all the time. But if you’re trying to land a fish or avoid a boat, it could be very serious.
Like good quality regular sunglasses, polarized lenses should also reduce UV radiation. UV protection is essential if you spend a lot of time out on the water.
The Danger of UV Radiation
Any time you’re out on the water, you need glasses to protect your eyes. The damage from UV rays can’t be ignored. It does more than just give sunburns. This is especially true for children. Their eyes and skin are more sensitive to UV rays. They absorb more, but the damage won’t be present until later in life. By age 20, you will have already experienced 80% of the UV radiation your body can handle in your lifetime.
UV radiation can lead to cataracts, macular degeneration, even corneal sunburns.
One thing to be on the lookout for is how the lenses you buy offer UV protection. Cheap glasses may say they offer high UV protection, but it’s only the result of a spray on coating. This will come off when you clean the glasses. That will leave you with tinted lenses that offer no protection at all.
How to Tell if Your Sunglasses Are Polarized
Polarized glasses do not look very different from regular sunglasses. That means you may not be able to tell if you have a polarized pair or not. Worse, some lower-quality glasses market themselves as polarized when they are not. That means you need a way to tell the difference. There are a few methods you can use to determine if your sunglasses are polarized.
The Single Pair Method
If you only have one pair of sunglasses, this is how you tell if they’re polarized. You need to find a reflective surface, like water or a glass table. Get it in some bright light and look at it with your glasses on. Now tilt your head. You need to tilt to around 60 degrees. At a 60 degree angle, you should notice the light increasing in intensity. If that doesn’t happen, then there’s no polarization on your glasses. They’re just regular sunglasses.
The reason this works is that the polarization coating absorbs the horizontal rays. At an angle, the light doesn’t hit the same, so it should increase if they are truly polarized.
The Two Pair Method
If you already have one confirmed pair of polarized lenses, then this method is easy. Hold both pairs up so they are facing each other. Straight on you should be able to see easily through both pairs. Rotate one of the pairs to a right angle. The lenses should completely black out if they’re both polarized. If not, then your new pair is not polarized.
The Computer Screens Method
For this one, you just need an LCD display like a computer or a phone. All you need to do is look at the screen and tilt your head with the sunglasses on. If the LCD screen goes black, then your glasses are polarized.
The Sticker Method
If you’re buying a new pair of polarized sunglasses, then this method may apply. Some manufacturers include a test sticker on the lens of new glasses. Again, all you need to do is to tilt the lenses to an angle. If the sticker gets dark as you view it through the lenses, then you have a pair of polarized sunglasses.
The Test Card Method
Polarization test cards are another quick way to test sunglasses. Many businesses and websites that sell polarized glasses will also sell these cards. When viewed through true polarized lenses, an image will appear on the card. If you view them with your naked eye or normal sunglasses, they will appear blank.
You can get polarization tests cards for a couple of dollars.
Polarized Sunglasses vs Regular Sunglasses
As we have seen, polarized lenses filter horizontal light. But why is that different from normal sunglasses? And does it matter? Both sunglasses and polarized sunglasses filter ambient light. That makes it easier to see in bright conditions. But only polarized glasses reduce glare. Because they absorb those horizontal rays, clarity is greatly increased.
Polarized glasses cost often more but offer more. If you spent a lot of time near reflective surfaces, they are a necessity. Fishing and boating are greatly improved when you use polarized lenses. They just make everything easier.
Keep in mind, they don’t have to cost more. Some polarized glasses can cost you under $20.
It’s worth noting that if you use polarized sunglasses in the winter, there may be some drawbacks. Because of the glare reduction, it’s hard to see ice with polarized glasses on. If you do any ice fishing you may be unable to notice very smooth ice patches.
If you do the LCD screen test with your glasses, you’ll notice it’s hard to see. Reading screens in normal sunglasses is easier than with polarized ones. If you’re doing a job that requires frequent viewing of electronic screens, polarized may be a bad choice. For instance, pilots often wear normal sunglasses just for this reason.
Most sunglasses companies make both regular and polarized versions. You can get a good pair of Ray Ban sunglasses that are polarized if you want.