I often see parents asking what are the better eye care products, I want to say that if you want to protect your eyes, in fact, the best way is to stay away from electronic screens as much as possible, but this problem is sometimes melancholy, the online classes in the past period of time have too much impact on children's eyesight, and parents are also miserable. Now I finally don't have to take online classes, but children have also developed the habit of looking at electronic products, such as mobile phones, tablets, and TVs, so many parents are anxious about their children's vision, so are there any more eye-friendly electronic products?Personally, I feel that there are several issues that must be considered from the perspective of protecting eyesight. I'm going to talk to you today.
01. Choose a large screen as an alternative
A larger screen is definitely better. In fact, think about traditional TV,There is a control requirement for the best**distance,For example, this is a comparison table about the optimal distance,We can see that in fact, for the screen,It is necessary to maintain a certain distance to get the best**effect。
Or follow this table to distinguish the best distances at different resolutions.
The mobile phone itself is also a large screen as an interaction, in fact, from the first distance, it is more appropriate to maintain a long distance. However, for children, they can't help but get close to the screen, so in fact, not only is the ** effect not guaranteed, but it also causes strong light to enter the eyes, affecting vision.
Therefore, I recommend that for small children, it is better to have a large screen. After all, many smart TVs can now realize the screen projection function,In this way, you can project the content of the mobile phone to the TV,So that children can keep a certain distance。
Of course, on the basis of a large screen, some screen parameters are also worth paying attention to, for color screens, there are two main points, that is: blue light and strobe.
Let's talk about how blue light and strobe are harmful.
02. Reduce blue light
Blue light is a concept that has been mentioned in recent years, blue light is a high-energy visible light with a wavelength of 435 20nm, and it is also the highest energy light in the visible spectrum, so it is called HEV light (high-energy visible light).
Blue light is not only found in sunlight, but also in large quantities in the background light source of digital electronic devices such as mobile phones, LEDs, and computers.
In recent years, due to the widespread popularity of screen electronic products and the widespread emission of HEVs from electronic products, it has also led to a lot of discussions on the impact of blue light on human health, especially vision, including photochemical damage, photomechanical damage, For example, some studies have found that a large amount of blue light passing through the refractive medium of the eyeball to the retina, which may trigger the formation of lipid peroxides and the excessive production of reactive oxygen species, which will have a certain impact on cells in the retina and other structures, and increase retina-related diseases, such as retinitis pigmentosa and age-related macular degeneration [1].
Therefore, for blue light, it has become the focus of many products, the most typical is the field of glasses, many high-end lenses will add some coatings and other processes to filter blue light, to avoid people who have been exposed to the screen for a long time to be affected by too much blue light. Of course, in recent years, there have also been industrial technologies to actively reduce the blue light from the display.
03. Reduce flicker
Strobe is to look at the screen of another electrical appliance in the screen of one electrical appliance, and the screen of another electrical appliance will have a bright line that moves from the bottom of the screen to the top and then appears from the bottom. This goes on endlessly, giving us the impression that the image is flickering. I believe everyone should have felt this situation when shooting the screen with their mobile phones, as shown on the left side of the picture below, the display seen in the mobile phone screen will have bright lines crossed.
The main problem that causes strobe is alternating current. Since the alternating current is constantly changing, the intensity of the light source changes over time, and the result is the strobe of the screen.
Long-term strobe will not only affect visual comfort, but also cause some physiological diseases, such as migraine, so it is also an important idea to solve the problem of flicker [2]. The solution is to use direct current power supply, and the voltage amplitude and direction of direct current itself will not change with the continuation of time.
Therefore, by adding certain treatment measures to the alternating current, such as transformer + rectifier and other facilities, it can be converted to constant current, so that the strobe phenomenon can be reduced as much as possible, so as to reduce the impact of stroboscopy.
In general,For the display,Big is king,On this basis,It can reduce blue light and strobe,Then its eye protection effect can be improved,This is also the choice of display,Especially for children,Several points worth paying attention to。
1 Zhang Chu, Zou Yuping. Research progress on the damage of blue light to the retina and its protective effect. Chin J Ocular Trauma Occupational Ophthalmology,2012,32(6):476-480
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