| We wear sunglasses now all year round. Designer sunglasses represent not just a stylish accessory, they are indispensable to protect your eyes against ultra-violet radiation. The ultra-violet rays penetrating into the eyes may cause various ocular problems. Staying under the sun, in summer or in winter, is very harmful for your eyes. Our bodies were adapted to shield the eyes from sunlight – iris-contraction and squinting reflexes minimize the penetration of UV rays into the eyes. But the UV-rays are still active on a cloud day as well, so the mentioned natural defensive mechanisms are not sufficient for full protection.
That is when wearing sunglasses goes to the rescue. Modern sunglasses with UV protection cover are an effective device for individual protection from the UV radiation. For example, wide-brimmed hats provide just 50% ultra-violet protection and aren't efficient in relation to light reflected from horizontal surfaces such as water, grass and snow. That is the reason why your vision is misting and it's so difficult to drive a car when the sun shines brightly. Headaches and eyes irritation are momentary symptoms if you're under the sun rays for a long period of time. What is more, all this may bring to more serious illnesses with time. Sunglasses with good UV protection coat in their turn provide high level of UV protection and better vision in bright sunlight.
The variety of lenses with ultra-violet coat characteristics is great, so you'll probably need a guide to take a decision.
Firstly, don't forget that degree of darkening and color have nothing in common with the efficiency of ultra-violet protection. You have to pay attention to these characteristics when selecting the type of lenses depending on your activity. In this way, middle-dark lenses are perfect for daily wearing when at the same time staying under the bright sunlight for a long time demands dark lenses.
Sunglasses with polarized lenses are applied when driving or for water sports because this type of lenses diffracts the light reflected from smooth surfaces. For manufacturing prescribed sunglasses producers use photochromic lenses as optical transmission in these lenses is about 25-80 per cent.
Lenses used for various activities are also of different colors. In such a way, grey lenses are selected by painters and decorators. Green and brown lenses increase the contrast of colors. Numerous adherents of the sportive style give their preference to yellow lenses.
Doesn't matter what type of lenses you choose, make certain that your sunglasses are with good UV protection coat. |
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