Every time you turn around, you have another decision to make. Should I get an electric car? Should I buy 800 thread count sheets? Is it better to use a Mac or a PC? Do I prefer Coke or Pepsi? It almost gets a little overwhelming.
However, when it comes to making choices about your eyes, we’re here to help make it easy. And choosing sunglasses should be fun, not overly complicated!
So, first and foremost, you need to have sunglasses with UV protection. Ultraviolet light is electromagnetic radiation that emanates from the sun and gets transmitted in waves or particles at different wavelengths and frequencies. What’s essential to know is that it’s the reason you need to wear sunscreen to protect your skin. And when it comes to your eyes, UV exposure has been associated with an increased risk for cataracts, macular degeneration, and even development of ocular melanoma—a rare type of cancer.
Now when it comes to polarization, there is a little bit of choice. So how do you decide if you should get polarized sunglasses?
If you’re in a hurry, the quick answer is, unless you’re a pilot, heavy machine operator, or a voracious alpine skier, you should go ahead and get polarized sunglasses.
Of course, even for those folks, we might suggest that polarized lenses would be ideal for all the times they’re not flying through the air, grading a roadway, or barreling down a mountain.
The simple reason you should have polarized sunglasses is that it’s going to cut the glare and make it easier for you to see. If you spend any part of your day driving a car, you are going to benefit significantly from having polarized lenses. And when you realize the difference, you’ll likely be encouraging other drivers you know to make the upgrade.
Let’s look at why polarized lenses make such a difference.
It’s easy to assume sunlight is coming down from the sun and thus hitting the earth as vertical wavelengths. However, the truth is, we are exposed regularly to both vertical and horizontal light. The angle of the sun to the planet, not to mention the innumerable surfaces for light rays to bounce off of, means sunlight is effectively coming from everywhere.
Unpolarized lenses do a fine job of making it easier to see in vertical light conditions. They will often skew colours, making things much more red, pink or yellow, but they do improve the clarity of vision versus not having sunglasses at all.
The trouble is the horizontal light, especially when it’s been bounced off a reflective surface. When sunlight shines directly into unpolarized sunglasses, the tinted lenses are effectively useless. We call this horizontal sunlight glare. And when it hits you, it can obstruct your entire field of view. We all know how annoying it is when we’re out walking to get hit with a glare. However, when you’re driving, even brief moments of impaired vision can be extremely dangerous.
So how do polarized lenses work?
During the manufacturing process of polarized lenses, a chemical is applied that acts as a microscopic light filter. Because polarized horizontal lightwaves cause glare, the chemical-filter is oriented to block all lightwaves of a horizontal nature from passing through the lens. So while the glare is still happening, it is prevented from ever hitting your eyes.
If you want to see this in effect, stand in front of a perpendicular reflective surface wearing your polarized sunglasses (your car hood usually works well). Then, begin to turn your face to either side. You will notice that as you get closer to rotating the sunglasses to 180 degrees, the more the glare will become apparent.
The intriguing thing is that while things may seem a little darker in polarized sunglasses than non-polarized, because of the lack of horizontal light, without the glare images are considerably easier to see. And, this reduction of extra light has an additional benefit of reducing eyestrain overall, leading to faster visual recognition and quicker reaction times.
If you’re someone who spends a lot of time on the water, a good pair of polarized lense will be incredibly helpful. By cutting out the horizontal light, you will be able to see beneath the surface of the water, instead of being greeted by a shimmery ripple. If you find yourself attempting to manoeuvre a boat through unfamiliar areas or wanting to see where the fish are hanging out, this is going to be quite advantageous.
Quality is important
As with most products, there are a variety of options available for polarization. Cheaper quality polarized lenses usually only have a thin layer of chemical filter on the outside of the glasses. As such, these filters are not as effective and can have their polarization protection scratched off over time. Higher quality polarized sunglasses have a thicker chemical filter enclosed by two layers of lens material. The thicker the polarized screen is, the better able it is to block out glare. And by encasing it inside the lens, you prevent it from becoming diminished.
However, if your choice is between cheaper polarized sunglasses and non-polarized sunglasses, you are better having the lower quality polarized option than nothing at all.
Beyond merely seeing better in the sun
While cutting out the glare is the primary benefit to polarized sunglasses, there are some other significant advantages for folks who spend a lot of time outside.
A good number of people suffer from headaches as a result of light sensitivity. As polarization filtering has improved, many patients have noticed their symptoms decreasing considerably.
So why wouldn’t you get polarized sunglasses?
As mentioned above, polarized sunglasses are an excellent option for almost everybody. Of course, there are a couple of particular circumstances where blocking out the horizontal light can cause problems.
Liquid crystal displays, used in many instrument clusters and on mobile phones, can sometimes be challenging to read with polarized lenses. It won’t make much of a difference when you’re updating Facebook, but if you need to make subtle adjustments to a piece of machinery quickly, polarized lenses can be a hazard.
For this reason, people using bulldozers, or operating cranes are generally advised not to wear polarized sunglasses while working.
Pilots, on the other hand, are forbidden from wearing polarized sunglasses while flying. Like the crane operator, they need to make precise alterations to their control panels. However, in-flight, the ability to see glares can also provide advanced warning that an object is too close to your aircraft. Be that another airplane, a building, or even the ground.
In the case of alpine skiers, it’s pretty similar. When traversing high-altitude slopes at tremendous speeds, the ability to catch a glare from a change in the snow can assist you in negotiating around dangerous crevasses or mountain edges.
Although it’s necessary to reiterate that wearing polarized sunglasses driving too and from the job site, the airport, or the ski hill would be worthwhile for all of these people.