Function of the selection of sunglasses
all kinds of function sunglasses choice:
1, 100% uv filters or UV400: high quality the sun glasses should have this tag. Label sometimes written as the & # 8220; 400 nm uv absorption & # 8221; Said, in general, can provide complete uv protection.
2, can filter the 99% of the ultraviolet (uv) : A pair of quality sunglasses, should be able to filter between 99% and 100% of type A and type B ultraviolet light, and color to divide evenly, image deformation or other defects. Check sunglasses whether accord with a standard, can lift it, for some rectangular patterns, such as the floor, the lens slowly move up and down or so, if the line is always maintain a straight line, rectangle is qualified. Studies have pointed out that, in water skiing, snow skiing or sea people wearing inferior sunglasses than without the glasses, accept uv dose three times higher.
4, wraparound sunglasses: appearance design to prevent by the frame edge into the light, for often engaged in outdoor work or exercise, can provide special protection, and prevent the light reflected from behind in my eyes.
5 lenses, metallized or reflective lens: the lens plating on thin metal layers, can reduce all the light inside the eyes, but you can't put the uv filtering completely.
6, polycarbonate lens, lens space: polycarbonate fiber lens, is mainly used to manufacture jet canopy, riot shields and sports glasses. In fact, this kind of solid materials, any prescription lenses can make.
7, gradient lens: this kind of lens color won't change with the light intensity, two points single gradients and double gradient. Single layer gradient lens, lens from top to bottom color from deep to shallow, suitable for motorists, can stop the dazzling sunshine, at the same time also can let the driver to see the dashboard; Double gradient lenses, lenses, respectively is in the dark, color is light in the middle. This design, can stop by the water, snow, or reflected light of the sky.
the article title: the choice of functional sunglasses
post: glasses sunglasses factory network