Polarized vs UV Protection – Choosing the Right Sunglasses
If you're in the market for a new pair of sunglasses, you may have noticed the words “UV protection” and “polarization” are frequently used to describe glasses. Often, these words are used interchangeably, but there are key differences between the two, and believe it or not, they have nothing in common with each other. The primary difference between prescription sunglasseshas to do with light waves and how various filters affect them. You don't need a physics degree to understand the differences between both types of glasses – with a bit of background information, you will be able to differentiate between the two.
What is Polarization?
The light we see outside is produced by the sun, however, by the time it reaches your eyes, some of the light will come from other sources. The light we see is largely the result of sunlight reflecting off other surfaces, such as trees, asphalt, water, and grass. Much like a mirror, these surfaces reflect sunlight at varying intensities. Textured surfaces, such as trees and grass, are considerably less reflective than flatter surfaces, such as bodies of water or cars. Harsh glares are created by highly reflective surfaces, and these glares can be so intense, that they temporarily prevent us from seeing.
Polarized sunglasses possess anti-glare properties that reduce the need to squint by filtering out harsh reflected light. When a light ray interacts with a surface, the waves are scattered and move in different directions, eventually transitioning to a horizontal direction. Utilizing an inlaid filter, such prescription sunglasses can allow vertical light to enter while blocking horizontal light.Benefits of Polarization
For most people, the most obvious benefit of polarized prescription sunglasses is their ability to prevent glare. However, in addition to their glare-blocking ability, polarization can also:
- Prevent wrinkles around the eyes by reducing squinting
- Increase visual contrast
- Enhance the vibrancy of colors
- Relieve eye strain
- Improve vision
Polarized glasses are perfect for activities such as skiing, fishing, snowboarding, biking, and boating. They can also prevent car accidents by blocking glare from oncoming cars and the road.
What is UV Protection?
The vast majority of people know that ultraviolet rays are dangerous and can have a negative impact on one's health. UV light is a wavelength of radiation that can cause serious damage to the eyes, and its wavelength is higher than the visible spectrum of light – in other words, it can't be seen with the naked eye.
Contrary to popular belief, UV rays are even present on cloudy days and during the winter. Prolonged exposure to UV rays can cause irreparable damage to the cornea and retina, and result in cataracts, abnormal growths, and degeneration. In the most severe cases, they can even cause blindness.
Fortunately, there are sunglasses that provide protection from UV rays. The coating of these glasses blocks UV rays, and some glasses, primarily those manufactured from polycarbonate, provide built-in protection. Simply put, the ultraviolet filters contained in UV-blocking glasses absorb harmful rays before they can cause lasting damage to your eyes. When shopping for prescription sports sunglasses, make sure they have a UV rating of 400 or higher.
Benefits of UV Protection Polarization Vs. UV Protection
As mentioned above, polarization refers to the ability to filter out horizontal waves of light and soften unwanted reflections and glares. You may want to purchase these glasses if you prefer dramatic contrasts, increased color vibrancy, and improved clarity of vision. On the other hand, UV-blocking glasses prevent UV rays from entering the eyes and damaging the retina and cornea.
Not all UV-blocking sunglasses are polarized and vice-versa. Just because a pair of glasses is advertised as polarized doesn't mean they can block UV rays. Always prioritize sunglasses with UV-blocking properties. The ability to prevent glares is great, but the ability to prevent permanent damage to the eyes is even better.