What should I pay attention to when buying sunglasses:
1. First observe whether the lens has scratches, impurities, bubbles and stripes, and check the outer packaging of sunglasses. Regular sunglasses should be marked with product name, color, diameter, quality grade, manufacturer's name and trademark. Sunglasses with anti-UVA, UVB and CE signs on the mirror or tag can guarantee to block some ultraviolet rays.
Try wearing sunglasses to see if you feel dizzy or have a headache. At present, there are some myopia sunglasses with degrees on the market, but because the pupil distance and other indicators vary from person to person, consumers had better not choose these sunglasses with degrees without professional guidance.
3. Point the two corners of the sunglasses in your hand at the fluorescent lamp and let the reflective strip of the mirror roll gently. If you find that the shadow of the fluorescent lamp reflected by the mirror is wavy and twisted, it proves that the lens is uneven, and such a mirror will damage your vision.
4. The lens should be flat and transparent. The materials of sunglasses are glass and resin, and the best sunglasses should be polarized lenses. It is made of light and precise synthetic resin like contact lenses, and consists of seven thin layers, the outermost two of which are superhard wear-resistant layers; The second layer and the sixth layer are shatterproof reinforcement layers; The third and fifth layers are ultraviolet filter layers, and the middle layer is polarization filter layer. Polarized lenses can effectively filter reflected light and harmful ultraviolet rays, and have the functions of shatterproof and wear resistance, so they are the most popular sunglasses.