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The indicator of light efficiency is mainly measured by the brightness and illumination of LED lamps. However, considering the quality of light, there are many other parameters involved. Color temperature is one of them.
Recently, it was sponsored by Gaogong LED, and the results of the sixth round of market test of China LED Lighting CLEAR, jointly issued by G20-LED Summit and third-party testing institutions, were released. The LED lamps of this round were tested in 18 models. 15 manufacturers.
The LED tube test is tested according to the method required by the LM79-08 standard. The test items cover total luminous flux, light efficiency, correlated color temperature, color rendering index, total harmonic distortion, power factor, etc., and the test results are the latest DLC in the United States. (V2.1) requires a comparative analysis.
The test results show that among the 18 types of LED tubes tested, none of the lamps have a color temperature index that meets the requirements of the latest DLC (V2.1) in the United States (≤5000K).
Among them, there are 16 products with measured color temperature exceeding 6000K, and the other two color temperatures are also above 5900K. Among them, Opal Lighting's op-3014-120 T8 lamp color temperature is as high as 7895K, and the color temperature of the logo on the box is 6500K, which exceeds the nominal data by 21.5%. According to the consistency standard of color temperature plus or minus 250K deviation, exceeding the standard by 17%.
Chen Zhaojun, chairman of Zhanjiang Chikan Guangpin Lighting Co., Ltd. told reporters that the color temperature is related to some raw materials used by downstream manufacturers. “When the lamp bead is added to the PC cover and some other materials, the color temperature of the whole lamp will rise. The material will be different, and the color temperature will rise differently.â€
"When the color temperature is high, the luminous flux will be relatively high." Chen Zhaojun said that some companies do not rule out the color temperature in order to ensure the luminous flux. "The color temperature is too high, the human eye will feel less comfortable, so it is still necessary to maintain a certain balance. The most important thing is the comfort of light. Simply to increase the luminous flux is a bit upside down."
For the current consumer preferences in the Chinese market for the color temperature of the lamp, the market segmentation demand is more dispersed. Among them, the color temperature is below 3300K, the light color is reddish to give a warm feeling; there is a steady atmosphere, warm feeling; when illuminated with a low color temperature light source, the red color can be made more vivid.
The color temperature is 3000–6000K, and people have no obvious visual psychological effect under this color tone, and have a refreshing feeling; when using a medium color temperature light source, the blue has a cool feeling. This color temperature segment of the product is also the mainstream product in the current market.
The color temperature is more than 6000K, and the light color is blue, which gives people a feeling of coldness. When using a high color temperature light source, the object has a cold feeling.
"From the lamp I have tested before, basically the color temperature is also above 6000K, and rarely below 5000K." Zhang Kai, the engineer of the third-party testing organization Shenzhen Lixun Product Technology Service Co., Ltd. and this round of CLEAR testing The test results of the plan coincide. 
The reporter learned that color temperature is the most common indicator of the spectral quality of the source. The "warm light" color temperature is lower, while the "cold light" color temperature is relatively higher. As the color temperature increases, the proportion of blue radiation increases and blue light increases. At present, there is no clear conclusion in the industry that the color temperature of LED lamps is too high, which will cause blue light hazard.
An industry insider who asked not to be named said, "The results of the sample survey do not represent the entire market. LED lamps are used indoors and outdoors. There is no problem with outdoor color temperatures above 6000K."
The above-mentioned insiders told reporters that lamps with a color temperature of 3000K-5000K are more comfortable for the human eye and are more suitable for indoor use. "Our company mainly exports, the color temperature of the exported lamps is basically 4000-5000K, but now the domestic market generally pursues brightness, the requirements for color temperature are not so high."
>>>Report Download: Test Data Details 
[Text / high-tech LED reporter Liu Pingping] For LED lamps, people's general focus is still on the indicator of light efficiency, which is also seen in the recent release of new products from various companies. Seoul Semiconductor has introduced an upgraded package with a luminous efficacy of 180 lm/W; Ronda has released a 200 lm/W high-efficiency 360-degree LED tube; Citizen Electronics has introduced a 161 lm/W large-throughput LED source.