July 10 Pocket

July 10 Pocket
Dark or, more correctly, sunglasses - accessory favorite for both men and women. Not always used as intended - still popular jokes about how many girls use "the most fashionable this season glasses" solely as hair bands. So someone is not living without sunglasses that remains there even in the evening when the sun has long gone down over the horizon and in the cafes and clubs. And this is understandable, because a properly fitted eyeglasses can favorably adjust dabhi the shape of the face and give the person a special charm.
Sunglasses have become an integral part of the image, favorite thing and subject dabhi to collectibles. But today we will discuss only practical side wearing sunglasses: in fact, they protect from the sun and it is necessary for our eyes? Or sunlight rather useful than harmful?
In discussing this question, experts meet unanimously - ultraviolet dabhi radiation harms the retina of our eyes. It may burn the retina and, as a consequence - a premature deterioration of vision and even blindness.
However, to our eyes is small enough ultraviolet misses: the most rigid and harmful UV rays are filtered by the ozone layer, dabhi part of the radiation is blocked by the lens in our eyes. But the minimum that still reaches the retina can lead to problems. Surely you've noticed that a particularly sunny day eyes are very tired, they literally hurt. No wonder we start squinting, trying to somehow reduce the incoming stream of light, our body knows better dabhi than we that it is harmful, and that it is useful, and does not want to pass to the retina too much sunlight.
Thus, drawing conclusions from all the above, you can definitely say that sunglasses will certainly need you, especially summer sunny day, on the beach, where the water and sand (white) actively reflect the sun's rays, in the mountains or on a fishing trip, a sunny day in winter.
But it is better to avoid wearing dabhi glasses indoors, transport, in cloudy weather, at night, when the sunlight is soft and does not blind. The fact that the constant wearing glasses may develop dabhi a fear of light - photophobia. dabhi And then even minimal light will cause you severe discomfort.
A second question arises: what kind of glasses to choose? They are now sold in literally every corner. Suitable eye protection if not too expensive items from the shop next door, or should go to optics and fork over any brand sunglasses?
Here we come to the most interesting part. Sunglasses are not always sunscreen. Yes, they reduce the brightness dabhi of the color, we become comfortable, we stop squinting and eye damage ...! Because ultraviolet light continues to penetrate through these darkened lenses, and our deluded reduced dabhi luminosity pupil expanded quietly these UV rays miss! Besides, enough cheap plastic glasses of poor vision may just ruin (eg, due to the different alignment glasses, ie, because the glasses simply curves), and through them you will see a distorted, with incorrect color reproduction .
Quality sunglasses can be glass or plastic lenses, but they have to be written by the degree of protection from UV radiation. Or the seller must be certified on the products, dabhi which should include all the characteristics. Nakleechki like "100% protection against UV rays" and "Full UV absorption" should not believe, especially if they decorate glasses cost 300 rubles.
By the way, if we talk about the price of high-quality sunglasses with UV protection, then in principle you will be able to meet the 1500-2000 rubles. Of course, it would hardly be branded model, but the main thing - eye protection. GUCCI will cost exactly at least 5000 rubles. Of course, a little expensive, in my opinion. But very well-known dabhi companies value their name and the quality of its products and, therefore, for this amount you buy not just the lens in the frame, but the certainty that frame will not warp on the second day, the cogs will not fall out, and do not scratch the lens, the degree of UV protection as specified in the documents, and you do not cause harm to your eyes.
Wander through professional opticians, see Estimate, read the documentation that you can provide it. Unfortunately, my search raid on the network showed that the online store relies dabhi on the design of frames, dabhi but the information about the UV protection is not specified. Perhaps, in such cases it is necessary to write in support, dabhi to clarify the characteristics dabhi of points, ask to send certificates.
Photochromic lenses are popularly called "chameleon". Chameleons are indoors conventional glasses (even if the room is sunny enough), and when entering the street is dark, and depending on the light intensity. Principle of photochromic lenses based on the content in the material of a photochromic lens material molecules which react to ultraviolet.
Do chameleons