At their best, sunglasses should shield your eyes from uncomfortably bright sunlight and damaging UV radiation. Unfortunately, not all sunglasses perform these important functions. Knowing what to look for before you buy your next pair of shades will help ensure the sun is easy on your eyes.
Continual exposure to the sun’s ultraviolet (UV) radiation increases your risk of developing cataracts and age-related macular degeneration (a disease that destroys both the sharpness of your eyesight and your ability to see objects in your central field of vision).
Contrary to popular belief, dark lenses and an expensive price tag aren’t indicative of top-notch quality. Here are some characteristics to keep in mind when you’re shopping for sunglasses that’ll provide you with optimum eye protection.
High percentage of UV blockage: Make sure the shades you’re considering clearly state that the lenses block at least 95 percent of UVA rays and 99 percent of UVB rays. If the label says the glasses block 100 percent of UV rays, that’s okay too. It’s just a concise way of saying the lenses block both UVA and UVB light.
Larger lens size: Choose a style with big lenses to ensure that your entire eye area is shielded from the sun. If the top of the sunglass frame reaches your brow bone and the bottom reaches the top of your cheek bone, you’re covered.
Guards against glare and UV rays: Mirrored lenses, polarized lenses and the like may reduce glare, but they don’t automatically cut out UV rays. Before choosing one of these sunglass types, make sure the label specifies the percentage of UV protection you’re getting. This goes for dark lenses too. Even a black lens won’t shield you from UV rays if it’s not coated with a UV protectant.
Polycarbonates are one type of lens that automatically comes with UV coating. These lightweight lenses are not only several times more impact resistant than other lenses, they also block out 100 percent of UV light.
Take note of how colors change when you’re looking through the sunglasses. Some lenses, including the popular amber-colored blue-light blockers, actually distort colors and can make it difficult to distinguish traffic signals. Stick to brown or gray lenses if accurate color recognition is important.
Wrap-around shape: Glare and damaging UV rays can find their way into your eyes through the sides of your sunglasses too. So if you want to protect your eyes from as much peripheral light as possible, consider sunglasses with wide arms that wrap around your temples.
dummies
Source:http://www.dummies.com/how-to/content/how-to-choose-sunglasses-for-optimum-eye-protectio.html
No comments:
Post a Comment