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Non-study reading table lamps, from the point of view of energy saving, LED certainly no comment, but if it is for a long time to read and study the choice of table lamps, from the comprehensive health lighting index of the judgment, if not customized, to buy the perfect one, it is true that you have to spend a lot of effort and silver! Just as after every light source revolution, the old generation of light source products are still because of a few particularly good parameters and will not be completely eliminated, at present, it seems that LED as a desk lamp light source will not be perfect over all non-LED light source.
LED desk lamp quality is still uneven. A common problem is that because many of these lamps use low-power LEDs as a light source, their total power is not enough to achieve sufficient illumination. Whether it has any impact on eye health depends on its function. If as a bedside lamp, night light, the illumination requirements are not high, the impact may not be significant. But as a reading lamp, insufficient illumination will accelerate visual fatigue, not conducive to the protection of eyesight.
Secondly, most of the LED lights used in white LED, the principle is that the blue chip coated with phosphor, the chip's blue light excitation phosphor emits yellow-green light, yellow-green light and blue light synthesis of white LED, because of its lack of red light component, so the color temperature is high, some far more than the range of color temperature suitable for indoor lighting. Of course, the LED blue spectrum in the desk lamp when used in close proximity to the eye damage is also need to focus on prevention!
In addition, due to the small size of the LED light source, high brightness, the LED desk lamp anti-glare measures are also higher requirements. If there is no careful selection of the angle of light output, grille, lens and other anti-glare measures, may produce direct glare, not only produces a sense of harshness, but also reduces the visual function, is not conducive to reading.
My selection of learning desk lamps mainly refer to the following articles, regardless of whether the choice of LED light source, to achieve the following standards the more lights, the more I think it is a good desk lamp:
1, the national certification requirements: learning desk lamps must be through the national mandatory 3C certification, and in the validity period;
2, the use of warm-white light: the color temperature of 3200-3400K, from visual Physiologically speaking, warm white light source most in line with the human eye visual physiological needs;
3, intuitive desk lamp: the light can not be direct or refractive eyes, strict elimination of piercing eyes. Simple test method is as follows: the eyes from the height of the desktop reading and writing 400mm, from the center of the light source of the lamp at a horizontal distance of 600mm, you should not see direct or refracted light in the lampshade;
4, desk lamp light intensity test: the center of the light source from the height of the desktop reading and writing 400mm at the illuminance in the 750-1000 Lx for the best visual light environment;
5, clarity and color reproduction of the simple test: stretch out the palm of the hand, palm up, placed under the lamp light 30 cm, such as the observation of the palm lines clear, palm surface fingers reddish is that the desk lamp light color is clear, color reproduction is good; and vice versa fuzzy, yellowish color, grayish desk lamp light is poor. Color rendering index Ra in more than 90 of the clarity of the lamp is much higher than the market share of more than 95% of the ordinary color rendering lamps.
6, the selected power of the light source: some sources claim that LED lamps and 25-40 watts of incandescent desk lamp brightness is equivalent to the most suitable, in fact, is not appropriate. After testing, the center of the light source from reading and writing desktop height of 400mm, 25-watt incandescent light only 220Lx, 40-watt incandescent light is only 350Lx; even if you reduce the height to 300 mm, 25-watt incandescent light is only 330Lx, 40-watt incandescent light is 550Lx, less than the best visual light environment minimum standard 750 Lx requirements.
7, learning desk lamp should be a certain height, when the light irradiation surface, light uniformity, 40 centimeters away from the desktop illuminance should not be less than 750 Lx; desk lamp bracket should also have a certain length, easy to stretch contraction, suitable for computer operation, drawing calligraphy, learning to play the piano multi-purpose use.
The truth is, it is a bit difficult to find LED desk lamps on the market that meet all the above requirements. Therefore, there are many customers can only spend more than 10 cents a day on electricity, the choice of 3200-3400K or so of high-definition halogen professional reading desk lamp to meet the optical parameters and eye health requirements.
The visual lighting environment of home reading and writing work is very important, the most important thing when reading and writing work at home is to learn the visual lighting environment, specifically the quality of the quality of learning desk lamps. Study desk lamps on the market a variety of eye lamps, energy-saving lamps, incandescent lamps and LED lamps. Discriminate the quality of the quality of learning desk lamps, if the light color white glare, or light color dim, illumination is not standardized desk lamps, should not be used as a family learning light source, because of that on the development of vision will have a negative impact.
Looking forward to more high color rendering, warm white tones, high luminous efficacy, affordable professional LED reading desk lamps to the market, to provide a clear and environmentally friendly learning visual lighting environment, to reduce eye fatigue, alleviate ciliary spasms, and contribute to the protection of the development of the health of our eyesight.