There is no scientific argument LED blue eye

Since the beginning of this year, there have been frequent reports that LED “blue eyes overflow” and some people are afraid to use LED lights. What is the blue light in the LED lamps? Are they really harmful to the eyes? Are the LED lamps safe? In this regard, the industry generally believes that there is no direct scientific evidence to say that Blu-ray hurts one eye.

LED Blu-ray into "injured eye killer"?

From incandescent lamps to energy-saving lamps to LED lamps, in recent years, society has paid more attention to energy-saving lighting products than ever before. Among them, the LED lamps known as the fourth generation of light sources under the dual promotion of industrial capital and government subsidies have shown explosive growth in the past two years. Wang Kangping, vice president of the Shanghai Semiconductor Lighting Engineering Technology Association, once estimated that if 50% of the country's light sources were replaced with LEDs, the saved electricity would be equivalent to regenerating 2.5 of the Three Gorges Project each year. However, while the home lighting industry is advancing with enthusiasm and prosperity, some medical professionals and electric light source experts have pointed out that many LED lamps have serious blue-light spillage problems, which will cause irreversible damage to the human eye retina.

The same color temperature of the LED lights the same security LED lamps really have a vision damage it? At the 2013 China (Shanghai) International Semiconductor Lighting Application Technology Forum held in 2013, the participating experts discussed the issue of Blu-ray security. Zhe Tongsheng, professor of Optoelectronic Information Engineering Department of Zhejiang University, introduced that visible light is composed of seven colors: red, orange, yellow, green, cyan, blue, and purple. Light with a wavelength of 435 to 500 nm corresponds to blue and cyan. The scientific community generally refers to the 400-500 nm wavelength range as the "blue region."

Associate Professor Zhang Shanduan, deputy director of the Institute of Electric Light Sources at Fudan University, pointed out: "The principle of white LEDs is that blue LED chips excite yellow phosphors to form white light after conversion. Blu-ray damage refers to the 400-500 nm blue wavelength of light sources. If the brightness is too high, the eyes are long. Time-directed light sources can cause photochemical damage to the retina. The degree of blue light damage depends on the amount of blue light that the human eye has accumulated in the light."

From a technical point of view, "the current technology commonly used in LED lamps on the market is "blue chip + yellow phosphor", so that the content of blue light in LED lights is relatively high, but this does not mean that LED lights are more injurious than other lamps." Zhang Shanduan pointed out that in the comparative experiments they performed, the safety performance of the same color temperature LED lamps and energy-saving lamps was almost the same.

The reporter learned that color temperature is the most common indicator of the spectral quality of light sources. The "warm light" color temperature is lower, and the "cold light" color temperature is relatively high. As the color temperature increases, the proportion of blue radiation increases and blue light increases. At the same time, the brightness also affects the proportion of blue light. In general, the same color temperature of fluorescent and LED lights, as long as the latter's brightness does not exceed the former 3 times, basically no harm. However, for individual LED lighting that is too bright, the proportion of blue light may exceed the safe value. Zhang Shanduan said that with the maturity of LED technology, manufacturers no longer need to blindly increase the color temperature and power of lamps to achieve high brightness, and objectively reduce the possibility of excessive blue light.

LED supervision urgently implements the mandatory national standard. “If you purchase qualified lamps and use them properly, LED lamps are no more dangerous than traditional lamps.” Insiders pointed out that there are currently more than 3,000 LED lamp manufacturers in China, and the current national standards in China. In the Light Biosafety of Lamps and Lights System, a clear description of the hazards of blue light and the calculation method for quantification was made, and it was pointed out that there is no difference between LED lighting products and other light sources, and it falls within the safe limits specified by the limits of exposure radiography. .

However, experts say that this standard is a "recommended standard" rather than a "compulsory standard." Prof. Tong Tongsheng said that according to the intensity of blue light, photobiological safety standards for blue light have been established, and various values ​​of possible blue light hazards have been set. For example, a light source product that does not have a Blu-ray hazard is called a “zero product”; a product that has less blue light hazard and the eyes cannot look directly at the light source for a long time is called “a product”; a light source that has a large blue light hazard is called For "second-class products." Currently used as the basic zero-class and one-class LED lighting, if it is the second category is forced to mark "eyes can not stare at."

Industry: There is no scientific evidence whether LED lights hurt eye For the topic of LED lamp Blu-ray overflow to human eyes, Sun Xinghuai, dean of the Shanghai Eye, Ear, Nose and Throat Hospital, said that Blu-ray is not unique to LED lights, and it is rich in mobile phones and computer screens. Blu-ray, at home and abroad, hospitals have not yet seen one case of eye injury due to the use of LED lights. According to Yu Anqi, director of the National Electric Light Source Quality Supervision and Inspection Center (Shanghai), answering this question is like answering the question of whether the sun is safe. In general, the sun is safe, but if you look at the sun, it can cause eye burns.

The National Semiconductor Lighting Engineering R&D and Industry Alliance and the China Illuminating Society recently organized more than 10 well-known domestic experts to discuss the issue of whether “blue light is hurting the eyes” and formed a white paper titled “Ordinary Lighting LED and Blu-ray.” According to Professor Zhou Taiming, an expert from the white paper writing group, “The blue light exposure of the white LED light source on the retina of the human eye is similar to traditional light sources such as fluorescent lamps and metal halide lamps, and will not cause harm to human eyes.”