Ahhh…there's nothing quite like lounging by the pool in the sunshine, sipping on an ice-cold lemonade and enjoying the warm weather. Of course, the sunlight bouncing off the cool pool water can hurt your eyes, so we hope you have a cool pair of shades.

Do you like to wear sunglasses? Not only can they sharpen your image, but they perform an important function: protecting your eyes from the harmful rays of the sun. And they're not just for summertime, either. sunglasses can be just as important in the winter!

When you're sledding or skiing, the bright light of the sun bouncing off the snow can blind you. A good pair of sunglasses will help you enjoy your outdoor sporting activities to the fullest. Your parents might also want to wear sunglasses when they're driving if there's a lot of snow on the ground.

sunglasses have been around a long time. Glasses with flat panes of smoky quartz were used to protect the eyes in China as early as the 12th century. Further experimentation with tinted lenses occurred in the mid-18th century.

It wasn't until the late 1920s, though, that inexpensive, mass-produced sunglasses were introduced to the United States by Sam Foster. Foster's sunglasses became popular on the beaches of Atlantic City, New Jersey, where he sold them under the name Foster Grant from a Woolworth store on the Boardwalk.

Today, there are an amazing number of options when it comes to sunglasses. You can get cheap sunglasses at discount stores for a few dollars. On the other hand, you can also get sunglasses at specialty optical shops that cost hundreds of dollars.

What kind of sunglasses you need and how much they cost will depend upon the materials and technologies used. For example, the cheapest sunglasses use nothing more than tinted glass or plastic to help protect your eyes from bright sunlight. Depending upon the color of tint used, the sunglasses will absorb certain types of light and reflect others. These cheapest sunglasses rarely offer the kind of protection your eyes really need.

More expensive sunglasses will likely have polarized lenses. These special lenses help to block glare from light reflecting off of various horizontal surfaces, such as water or a highway. polarized glasses only allow vertically-polarized light through, so glare from a lake, for example, will be blocked.

High quality sunglasses will also usually feature protection from various types of ultraviolet (UV) radiation. These are the sun's harmful rays that can cause sunburn and many types of eye problems. Of course, high prices don't always mean the best protection. Instead of judging your sunglasses by their price tag, instead look at what percentage of UV rays they block.

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