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From the perspective of energy saving, LED is definitely not necessary for reading lamps in non-study, but from the perspective of comprehensive health lighting index, it really takes a lot of energy and money to buy perfect lamps if they are not customized! Just like every light source revolution, the older generation of light source products will not be completely eliminated because of some particularly excellent parameters. At present, LED as a table lamp light source will not completely defeat all non-LED light sources.
The quality of LED desk lamps is still uneven. A common problem is that because many of these desk lamps use low-power LEDs as light sources, the total power is not enough to achieve sufficient illumination. Whether it affects eye hygiene depends on its use function. If it is used as a bedside lamp and nightlight, the requirements for illumination are not high, and the impact may be small. However, if it is used as a reading desk lamp, insufficient light will accelerate visual fatigue, which is not conducive to protecting vision.
Secondly, the principle of white LED used in most LED lamps is that the blue chip is coated with fluorescent powder, and the blue light of the chip excites the fluorescent powder to emit yellow-green light. The white LED composed of yellow-green light and blue light has a high color temperature due to the lack of red light, and some of them far exceed the suitable color temperature range for indoor lighting. Of course, the damage of LED blue spectrum to the eyes when the desk lamp is used at close range also needs to be prevented!
In addition, due to the small volume and high brightness of LED light source, anti-glare measures for LED desk lamps are also required. If you don't choose the light angle carefully and take anti-glare measures such as grating and lens, there may be direct glare, which will not only produce glare, but also reduce the visual function, which is not conducive to reading.
I mainly refer to the following points when choosing a study desk lamp. Whether LED light source is selected or not, I think the more lamps that meet the following standards, the better:
1, national certification requirements: the study desk lamp must pass the national compulsory 3C certification and be within the validity period;
2. Adopt warm white light source: the color temperature is 3200-3400K, which is most suitable for people's visual physiology.
3, intuitive desk lamp: light can not be direct or refracted eyes, strictly eliminate glare. The simple test method is as follows: when the eye height is 400mm away from the reading and writing desktop and the horizontal distance is 600mm away from the center of the lamp light source, you should not see the direct light or refracted light in the lampshade;
4. Detection of desk lamp illuminance: The best visual light environment is when the illuminance is 750- 1000 Lx from the center of light source to the height of reading and writing desk 400mm;
5. Simple test of clarity and color reproduction: put your palm up and put it 30 cm under the lamp. If the palm lines are clear and the palm fingers are rosy, it means that the lighting is clear and the color is good; On the contrary, if it is fuzzy, dark yellow or gray, the light of the desk lamp is poor. The clarity of a desk lamp with a color rendering index greater than 90 is much higher than that of an ordinary color rendering desk lamp with a market share greater than 95%.
6. Selection of light source power: It is claimed that the LED desk lamp is most suitable when the brightness is equivalent to an incandescent desk lamp of 25-40 watts, but it is not suitable. According to the actual measurement, when the center of the light source is 400mm away from the reading and writing table, the illumination of the 25-watt incandescent lamp is only 220Lx, and that of the 40-watt incandescent lamp is only 350Lx. Even if the height is reduced to 300 mm, the illumination of 25-watt incandescent lamp is only 330Lx, and that of 40-watt incandescent lamp is 550Lx, which can't meet the requirements of the minimum standard of 750 Lx for the best visual light environment.
7. The study desk lamp should have a certain height. At this time, the illumination area is large and the illumination is uniform. The illuminance at 40 cm from the desktop should not be less than 750 Lx. The table lamp bracket should also have a certain length to facilitate expansion and contraction. Suitable for computer operation, painting calligraphy and learning to play the piano.
In fact, it is a little difficult to find LED desk lamps that meet all the above requirements in the market. Therefore, many customers can only spend 10 cents on electricity every day, and choose a high-definition halogen professional reading desk lamp of about 3200-3400K to meet the requirements of optical parameters and eye hygiene.
The visual lighting environment of home reading and writing homework is very important. The most important thing to watch writing homework at home is to learn the visual lighting environment, specifically, to learn the quality of desk lamps. There are many kinds of study desk lamps on the market, including eye protection lamps, energy-saving lamps, incandescent lamps and LED lamps. Judge the quality of the study desk lamp. If the light color is white and dazzling, or the light color is dim and the lighting is not standardized, it is not suitable as the light source of the family study, because it will have a bad influence on the development of your eyesight.
We expect more professional LED reading desk lamps with high color rendering, warm white tone, high light efficiency and moderate price to be put on the market, providing you with a clear and environmentally friendly learning visual lighting environment, reducing eye fatigue and ciliary muscle spasm, and helping to protect the healthy development of your vision.