The sun is shining and all signs point to spring – finally – being on its way. However, this time of year also comes with challenges. Skies clear of the haze or pollen of summer make for brighter-seeming days. Snow on the ground reflects sunlight, increasing glare. Likewise, rising temperatures cause snow to melt, making roads wet and reflective as well.
To combat these, you could always just stay indoors, or only go outside on rainy days. But let’s suppose you want to get out and enjoy the feeling of the sun on your skin for the first time in a few months. In that case, a pair of sunglasses are your best bet.
So, you’re looking to buy a new pair of sunglasses. That is an excellent decision. Not only do quality sunglasses have a range of health benefits, from helping to prevent cancer to helping to promoting eye health, the right pair can complete the look you’re going for.
If you’ve ever gone shopping for sunglasses, you know that you are bombarded by choices. Choices in make, frame style, lens shape, lens color and hue, choices in mirroring… There is a lot of thought involved in picking out the right shades.
Once you’ve waded through all that, many quality sunglasses manufacturers offer you one final choice: Polarized or Unpolarized?
Generally, polarized sunglasses are more expensive than unpolarized. So that begs the question, are they worth it? To make that choice, and answer that question, you should know what polarized sunglasses are, what they do, and why you should wear them.
What Are Polarized Sunglasses?
Simply put, polarized sunglasses are sunglasses with a clear coating that acts to reduce glare.
They were first used by people who spent their time on or near the water. Polarized sunglasses helped boaters see through the water to locate potential hazards and fisherman see the fish they were trying to catch. Likewise, by reducing the glare off the water, polarized sunglasses help both to see across the water.
How Do Polarized Sunglasses Do What They Do?
We’ve already established that polarized sunglasses reduce glare, but how do they do what normal (and less expensive) tinted glasses can’t?
The answer to that is in how light behaves. Don’t worry, we won’t get bogged down in the science.
When light is emitted, such as the sun does all the time, the waves are unpolarized. That means that the light waves are (essentially) vibrating in all directions at once. When the light enters the Earth’s atmosphere it is filtered in a way that it is polarized, or vibrating in one direction. However, when light is reflected off of something, it changes polarization to vibrate parallel to what it reflected off of. So, as the light waves pass through the atmosphere, they are reflected off of things like clouds, dust, pollen, and pollution. As well, when the light reaches the ground, it is reflected by flat objects like roads, bodies of water, or car hoods.
All of this combines to unpolarize the light waves again, creating glare.
The coating on polarized lenses serves as a filter to block out the light that isn’t polarized vertically.
It might help to think of the coating on polarized sunglasses as a vertical picket fence. Any light that is vibrating up and down can get through, while anything vibrating from side to side is blocked.
As you can see above, when the polarized sheet is held one way, all the light goes right through. However, when it is rotated 90 degrees, the glare is eliminated and you can see through the water.
Benefits of Polarized Sunglasses
So then, now we know how and why polarized sunglasses work, but that doesn’t tell us what good they are doing you.
First, polarized lenses make a big impact in the comfort of your sunglasses. By reducing glare, the polarized lenses will go further to reduce eye strain than normal tinted lenses will. That will help your eyes keep from getting fatigued, and help to reduce your overall fatigue.
Next, polarized sunglasses help to improve your ability to see, making your sunglasses more effective. By reducing glare, they help to cut down on haze when you are looking at something in the distance. As well, polarized lenses help to make it easier to differentiate between colors on a bright day.
Also, if you are playing an out-door sport such as golf, baseball, or anything on the beach, having a pair of polarized sunglasses can help to improve your performance. By reducing glare and improving how well you see colors, it can make it easier to track objects in flight or see details in the terrain.
Finally, polarized lenses can help to improve your safety in your day-to-day life. By reducing glare on snowy or damp roads, your polarized sunglasses will help you to be able to see hazards in your way. This is particularly true if you already have vision issues or have recently had eye surgery.
It does also bear mentioning that polarized lenses do not block ultraviolet light by themselves. However, polarized sunglasses from quality manufacturers are often also treated with a coating to block ultraviolet rays. That will help to prevent snow-blindness (which is essentially a sunburn on your cornea) and cancer.
Should I Buy Polarized Sunglasses?
Polarized lenses offer a number of advantages over regular tinted lenses. They reduce glare, increase comfort, increase performance, and (in some cases) are safer than similar but unpolarized, lenses. Some manufacturers even offer polarized sunglasses that can be ground for a prescription.
There are, however, a couple drawbacks: Polarized lenses tend to be more expensive than the same (but unpolarized) glasses. Also, polarized lenses can make LED and LCD displays difficult to read.
It really is up to you to decide if you want to invest in polarized sunglasses, however many people who try them find that they prefer them to traditional sunglasses and will continue to get polarized sunglasses in the future.
The next time you are looking for a new pair of sunglasses, consider asking your eye care professional about polarized sunglasses.