Sunglasses: what are they for?
Except that now the glasses with sun protection are an essential fashion accessory that emphasizes a particular image and style of its owner, they also must meet the requirements of safety and protection. To the human eye harmful as UV and infrared radiation + very bright light. Correctly selected according to the level of opacity, high-quality sunglasses neutralize the bad effects and just a dark model, without the presence of UV filters can only hurt, because they "cheat" the human pupil, which in turn on a bright light is not narrowed, and absorbs even more UV radiation.
a Huge number of problems that appear in old age are a direct consequence of the neglect of glasses with sun protection at a young age, because invisible micro trauma to the eye, tangible negative effect is given only to accumulate, after a while (1 or 2 seasons of "exploitation" unsafe points). Plus, if you're not wearing sunglasses directly in the bright sun and will at the same time, squints, wrinkles around the eyes - the long wait will not make. by the Way, quality can be purchased in the online store https://glasses.ua/.
Sun Protection: Basic notation
the UV rays that reach the human eye are divided into UVB and UVA. While UVC rays are absorbed by earth's atmosphere.
of Course, in the degree of hazard these rays are not the same, but the sunglasses must have protection from both UVA and UVB rays. Now very often on the sticker on the lenses or label of sunglasses you can observe the inscription "UV-400", which means these lenses protect eyes from all without exception harmful UV rays, the wavelength of which is < 400 Nm. The other thing is that in many cases, the presence of this label is no guarantee of the presence in these glasses lenses with the same action (often, this is the place to be in the case of glasses of "questionable" origin and quality).
therefore, sunglasses are needed to fly only in safe places and only if they quality certificate.
Translated by "Yandex.Translate": translate.yandex.ru.
