Pocket PCs have become a toy for many children.
In modern society, electronic products such as mobile phones and PDAs have become a necessity for life. When many people leave, there will be an inexplicable anxiety. In public places, you can see the "low-headed people" everywhere, watch videos, play games, brush Weibo, WeChat... I don't know, these small screens are slowly invading our eyes. But in the end, how serious is this kind of harm? Recently, three medical staff from Zhejiang Eye Hospital concluded that their mobile phones and handheld computers are more harmful to the eyes than TV.
According to reports, three medical staff from the Zhejiang Eye Hospital allowed three children to use and watch mobile phones, PDAs, 42-inch LCD TVs and projectors in four days, by comparing the child's diopter, tear film break time and blinking. The number of times before and after changes to determine their degree of damage to the child's vision. The test results show that continuous observation of these four kinds of screens will lead to a short increase in myopia (pseudo myopia), shortened tear film rupture time, and fewer blinks, while mobile phones and PDAs have more impact on the eyes than TV and projection. . After one of the children played the 20-minute mobile phone, the right eye vision dropped to the level of 100 degrees of pseudo-myopia. Therefore, the test concluded that playing a 10-minute phone is equivalent to watching a 30-minute TV.
False myopia is a temporary reduction in distance vision, and vision can be restored if properly rested. If pseudo-myopia caused by visual fatigue is not relieved and controlled for a long time, it will cause the shape of the eyeball to change and form true myopia. True myopia can only correct and improve vision by wearing glasses, contact lenses or surgery, and can not really cure. The tear film is a film at the forefront of the eye. It is composed of lipids, moisture and protein. Its function is to protect and moisturize the surface of the eye and maintain normal vision. Under normal circumstances, the tear film is constantly updated. Every time we blink, the eyelids are coated with a layer of tears on the surface of the eye. If you don't blink for a long time, this layer of tear film will naturally rupture. This time is called the tear film rupture time, which should be more than 10 seconds. Shortening the tear film rupture time will cause a series of discomfort, such as dry eyes, foreign body sensation, burning sensation, itching, tearing and so on.
Although this "test" is not a rigorous design demonstration and implementation of clinical studies, the sample size is small, but it carries out some objective examinations (such as optometry, tear film rupture time and blink count measurement), so it is quite illustrative Some problems, more intuitively show the potential threat to the eyes of mobile phones, handheld computers and other electronic products.
The harm of electronic products such as mobile phones to the eyes is multifaceted. The most common is dry eye syndrome. When using a mobile phone, especially a game, because of the high concentration of the eyes, people will involuntarily reduce the number of blinks, and over time, the tear film will be abnormal and dry eye symptoms will appear. Another significant problem is the induction of myopia. This is especially important for young children who are still developing. In addition, there is a â€œstealth killerâ€ in the bright electronic display â€“ high-energy blue light. It can damage the retina, long-term blue radiation can even induce blinding eye diseases such as macular degeneration, and there is no particularly effective treatment for macular degeneration.
Although it is not realistic to isolate children in modern society from mobile phones, PDAs, etc., it is necessary to prevent under-age children (under 6 years of age) from accessing such supplies and strictly controlling contact time (less than one hour a day). of. Parents should encourage their children to participate in outdoor sports. Scientific research shows that outdoor activities have a clear role in preventing myopia. In addition, lutein and zeaxanthin have the effect of resisting blue light, so eating more blueberries, broccoli, spinach, alfalfa, corn, egg yolk and other foods can greatly help the health of the eyes.
The original title "PDA is a child toy expert: mobile phones are more eye-catching than TV"
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