How to judge whether a qualified sunglasses

Previous article we talked about the sunglasses what is the real role, but it remains to be seen whether the sunglasses sunglasses role play or not qualified, only qualified sunglasses can prevent ultraviolet light, blue light, provide comfortable visual enjoyment, so how to judge whether the sunglasses qualified? 1, can effectively protect your eyes, sunglasses can block UVA and UVB rays of 99% ~ 100%, filtering 75% ~ 90% of visible light. So must can achieve 99% qualified sunglasses to prevent ultraviolet ray, filtering, more than 75% of visible light. Test that you can use the following method: stand in front of the mirror try, if through the lens is easy to see their eyes in the mirror, then the color of the picture of sunglasses is not dark, filtering less visible, is, of course, there are a lot of this kind of candy color sunglasses, this is unqualified, can't say sunglasses is adornment effect more. Ms sunglasses factory YC9720 sunglasses C01 bright black/lenses grey 2, flat sunglasses should promise not to lead to vision distortion, distortion, or wear can cause discomfort such as dizziness. Test method: with sunglasses, unbend arm, observe the distant right or straight through lenses, Such as doors, Windows) , from top to bottom and move around slowly frames, if it is found that the distortion, deflection, bending, means that the lens optical defects, is not qualified. 3, sunglasses lens color should be uniform. If a region suddenly dim, it must be unqualified. Recommended reading: look from the two key indicators qualified sunglasses or not the weight of the other sunglasses should be evenly distributed on the nose and ears, be careful when we wear the radian of adjusting frame and nose position, guarantee the picture frame not pinch the bridge of the nose, also won't grinding ear, and eyelash should contact less than sunglasses, that is simple to determine whether a sunglasses qualified several methods, if you want to continue to learn, you can focus on sunglasses glasses factory network, more glasses for information waiting for you!
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