Blue light refers to the part of visible light with the highest energy and the closest to ultraviolet light, that is, the frequency of light with a wavelength in the range of 400-500 nm, and the color is blue and purple, so it is commonly known as "blue light". But not all blue light is harmful to the body. Under normal circumstances, blue light with wavelengths between 480-500 nm is not only harmless to our body, but also beneficial. Only short-wave blue light below 450 nm has the potential to harm the eyes.
First, cause photodamage to cells on the retina
On the one hand, the blue light energy causes photo damage to the cells on the retina, so that individual cell structures are destroyed, cell function declines, visual function decreases, eye fatigue, pseudomyopia, blurred vision, decreased vision, glaucoma, and serious cataracts, macular degeneration, etc.
Second, focus on the effect on melatonin secretion
On the other hand, blue light is the most sensitive light that affects the regulation of the biological clock, too much blue light enters the eye, stimulates the photoreceptor ganglion cells on the retina, thereby releasing signals to inhibit the secretion of melatonin in the pineal gland, resulting in insomnia in the absence of melatonin at night.
For people who use computers or electronic display devices for a long time, anti-blue light lenses can indeed effectively block some harmful blue light damage to the eyes, so that the eyes are more comfortable when working in front of the display, but there is no clinical data to prove that it has the effect of effectively improving eye soreness, dry eyes, vision loss, fundus lesions and so on.
However, the lens of adolescents and adults is slightly different, and the tissues of the eye have different sizes of light absorption, of which the main role is the lens, and the difference between the two lenses will lead to a significant difference in the transmittance of light. The strong light transmittance of the lens in children and adolescents makes the blue light intensity entering the fundus retina greater, that is, the risk of blue light is higher than that of adults.
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Therefore, many parents will wonder whether their children also need to wear anti-blue light glasses?
Many ophthalmologists said in science that children and adolescents do not need to wear anti-blue light glasses, because their vision is in the development stage, many physiological functions are not perfect, and they need to stimulate visual development through beneficial light. Short-wave blue light is not harmful when it hits the eyes, but also reaches a certain time and intensity.
In fact, scientific research has shown that there is no direct connection between blue light prevention and myopia prevention, and effective control of eye time and maintenance of correct eye posture are the key to preventing myopia. Wang Ningli, member of the National Committee of the Chinese People's Political Consultative Conference and head of the National Anti-Blindness Technical Guidance Group, suggested that the single use of electronic products should be controlled at 20 minutes, protecting the eyes, and looking far away is the most important.
References;
1.Cheng Tianwei. Analysis on the effectiveness of anti-blue light glasses[J].China Journal of Glasses Science and Technology, 2019(03):107-108.
2. Xu Xinru,Zhang Xujing,Li Yi,Kang Ying. Analysis on the quality and safety of anti-blue light glasses products[J].Glass Enamel and Glasses,2021,49(09):30-33.
3. Qian Jinwei. Are children and teenagers wearing anti-blue light glasses harmful to their eyes? [J].China Journal of Glasses Science and Technology, 2020(09):52-53.
4. Lin Kuanyu. Protect the eyes, anti-blue light glasses are not so reliable[J].Science Volkswagen (Primary Edition), 2021(09):21-23.
5.Li Ying. Anti-blue light glasses: artifacts or gimmicks[J].China Quality Miles, 2020(09):50-52.