In the hot summer, in order to protect the sun, many people choose to wear sunglasses to reduce the damage of the sun on the eyes. Be sure to choose qualified sunglasses, otherwise wearing improper is likely to cause “sunglasses syndrome”. At the same time, a pair of poor quality sunglasses not only can not resist ultraviolet rays, but also may cause great damage to the eyes. Strong UV rays can burn the eyes The energy radiation emitted by the sun, in addition to visible light, there are infrared light, ultraviolet light, etc., if improper protection, may cause damage to the eyes. How harmful can UV rays be to our eyes? We often hear of solar ophthalmia is an acute damage to the eyes caused by strong sunlight. After the clouds, calm water or large areas of snow reflect sunlight, the outermost corneas of the eyes are burned by UV radiation, and the eyes will experience severe pain, dryness, tearing, gritty foreign body sensation, conjunctival congestion, edema, etc. Too much sunlight can also induce chronic eye diseases, such as cataracts, macular degeneration, pterygium, chronic conjunctivitis, etc. “If you look directly into the sun, it may also cause eclipse retinitis”. Wearing sunglasses, on the one hand, can prevent the eyes from being acutely burned by ultraviolet radiation. On the other hand, it can prevent cataracts, macular degeneration and other chronic diseases of the eye, whether you need to wear sunglasses, mainly to determine the strength of the sun’s rays, not the season to determine, because the strength of the sun’s rays vary greatly from region to region. You can pay attention to the UV intensity mentioned in the weather forecast, if the UV intensity is high, try to wear sunglasses to avoid UV damage to the eyes. In addition, if the sunlight is reflected in the surrounding environment is strong, such as when you are on the sea, snow, it is best to wear sunglasses. Choose sunglasses with UV protection So, in the face of a wide range of sunglasses, how should we choose? It is necessary to have a pair of sunglasses in the summer, but if you choose a pair of poor quality sunglasses, not only can not resist UV rays, but also will make the pupil dilate, so that the eye lens to take in more UV rays. Therefore, the selection of sunglasses must take into account both health and decorative functions. Generally speaking, whether a pair of sunglasses has the function of UV protection, we can not discern with the naked eye. The product logo is a reference for consumers to buy sunglasses, the public can see in some product labels and glasses front such as: “UV400”, “blocking all UV” and other signs. In order to protect the health of the eyes, you should choose sunglasses with anti-UV function, try to eliminate the wavelength of 380nm below the UV. Children under 6 years old should not wear sunglasses for a long time Is it suitable for children to wear sunglasses? Children’s eyes are delicate and easily damaged by bright light, in this sense, children need to wear sunglasses more. However, it should be noted that children under 6 years old are not suitable to wear sunglasses for a long time because their visual function development has not reached the adult level and wearing sunglasses for a long time may form amblyopia. The correct way is to put them on your child when the sun is strong and take them off when the sunlight becomes weak or indoors. Glaucoma patients should wear sunglasses with caution. The reason is that after wearing sunglasses, the visible light entering the eye is reduced, the pupil is naturally open, the iris tends to accumulate in the atrial angle and block the atrial water outflow channel, over time, it is easy to induce acute attacks of closed-angle glaucoma, eye redness, eye pain, sharp loss of vision and other symptoms. Especially those with a history of glaucoma or a family history of glaucoma are prone to this condition. Therefore, glaucoma patients or people suspected of having glaucoma should not wear sunglasses, and people over 40 years old should be cautious about wearing sunglasses for a long time. Poor quality sunglasses become the invisible killer of the eyes Wearing sunglasses improperly can cause sunglasses syndrome: orbital or between the two cheeks will appear skin numbness, dullness of perception and other symptoms; breathing nasal discomfort, like a cold; some people will also feel a small bug crawling in the face, eyes sore, “this is because often wear side wide, frame thick, heavy weight of sunglasses caused by”. In addition, some people wear sunglasses regardless of the time and occasion, even in the twilight are wearing, which will increase the burden on the eyes, causing eye muscle tension, blurred vision, serious will appear dizzy, can not be long vision and other symptoms. Therefore, be sure to choose a pair of glasses for their own, do not neglect the quality of glasses for the sake of beauty, do not let the sunglasses become the invisible killer of the eyes. Tips: lenses should choose gray, teal, green sunglasses lens color, the effect is not the same, teal lenses can absorb the light in the purple, cyan, almost absorb 100% of the ultraviolet and infrared, and soft tones so that the eyes are less likely to fatigue; gray system can completely absorb infrared and most of the ultraviolet, and will not change the original color of the scene; green system glasses Green glasses also absorb all infrared rays and 99% of ultraviolet rays, and are good for eye protection. The color of the lenses should be chosen so that the color of the surrounding environment is not distorted, the edges of the object are clear, and the different color signals can be effectively identified. Research has found that the blue light in the sun can hurt the eyes, and blue lenses can not filter out the blue light in the sun, so it is best not to choose blue lenses when choosing sunglasses, in general, the darker the color of the lenses the stronger the shading effect, but does not mean that the ability to protect against ultraviolet rays is stronger, sunglasses lens color is generally good to medium depth, otherwise it is difficult to identify the color of traffic lights.