When parents choose eye lights for their children, they often think that the brighter the light, the better. This reminds me of the story of the white flour in the 1990s. We now know that white flour is due to the addition of whitening Agents, brighteners are harmful to people. Therefore, to determine whether a thing is good or bad, we must know its internal composition to determine it.
Here I will talk about the basic knowledge of light sources. The eye-protection light protects the eye because the high-frequency rectifier circuit makes people not feel the flicker of fluorescence. This is the technology of Philips in the 1980s, and all large and small manufacturers can do it now. The key to eye protection is the color rendering of the light and the color temperature of the light. Fluorescent tubes are used for eye protection lights. The main luminescent materials currently used are:
- Pure tri-color toner,
- Halogen powder,
- Mixed powder of the two.
According to the cost calculation, eye protection lights with a retail price of less than 100 yuan in the market can basically be said to be not eye protection lights, because eye protection lights that are not pure three-colors are actually eye protection lights, and they cannot be talked about. Eye effect. (The price of pure tri-base toner is nearly 10 times that of halogen powder) I will not analyze it here, and I will only talk about the color temperature in the tube of pure tri-base toner.
The light of the three primary color tubes is the phosphor yttrium oxide (red light, peak wavelength 611nm) and magnesium polyaluminate (green light, peak wavelength 541nm) which can emit red, green and blue light sensitive to human eyes. ) And magnesium barium polyaluminate (blue light emission, peak wavelength 450nm) mixed in a certain proportion into three primary colors of phosphors, so as to emit light closer to sunlight. The color temperature is the human eye’s perception of a luminous body or a white reflector. Under normal circumstances, from 10 noon to 2 pm, a clear and cloudless sky, without direct sunlight, the standard daylight is about 5000-5500K, But the light at this time is the most poisonous and dazzling.
led light fixture
Current energy-saving lights generally use a color temperature of 5500–6500K, and eye-protection lights generally use a color temperature of 4500-5500K. Many of our consumers feel eye pain after reading under a table light. The reason is that the color temperature and color rendering of the table light are not Suitable for reading at close range. It is easy to compare the same book under different color temperature lights. The higher the color temperature, the brighter the light, the more dazzling the reflected light, the lower the color temperature, the warmer the yellow, the softer the reflected light. , The less irritation to the eyes. Through experiments, we can see that the reading effect is the best when the color temperature is around 4000K, basically there is no reflection glare. And why there are only a few manufacturers using 4000K color temperature lights, there are only two reasons: one is that the higher the color temperature of the light, the cheaper, and the second is the higher the color temperature, the brighter the light looks, just like the addition of whitening agent Like flour, it looks good!
Therefore, to remind the majority of table light and eye protection users, the light of the table light is not as bright as possible, the light of reading and learning is soft, the standard color temperature is most suitable between 3800–4200K.