1, first of all to know the purpose of their own purchase sunglasses From the several types of sunglasses described above, we know that different types of sunglasses have different applications and populations. We want to buy sunglasses first to determine the purpose of their own purchase is to shade, or for the matching costumes play a decorative role? Is there any UV-protection requirement in addition to shading? Are there any special requirements for the safety of lenses?
Only clear these purposes, combined with the style and wear in my face the actual effect, can buy a pair of suitable sunglasses.
2, to learn to read product identification Not all sunglasses have UV-proof functions, a pair of sunglasses that meet the basic requirements of the standard, can only be said to block the light at the same time not through more ultraviolet light. If a pair of sunglasses can only block the intensity of light and can not obstruct the same amount of ultraviolet light, for the wearer, will accept more ultraviolet than without wearing sunglasses (wearing sunglasses, will reduce the luminous flux into the human eye, resulting in the wearer pupil enlargement). In the shop counter sales of sunglasses, its lenses, tag on or outside the packaging on the general have obvious uv380, uv400 and other similar signs, like in the clothing has its fabric component annotation, the consumer must carefully check when buying.