A study by the World Health Organization (WHO) Eye Association recently went on the Internet – studies show that between 2006 and 2008, blue light radiation caused more than 30,000 people worldwide to become blind each year. The Eye Association issued an orange warning at the end of 2009: "The potential hidden threat of blue light radiation to humans will far exceed the destructiveness of Sudan Red, melamine, SARS (SARS), H1N1, and invisibly devour human eyes."
News about Blu-ray hazards is frequently seen in the media along with such "research". There are reports in the country that an 8-year-old Shanxi child seems to be staring at TV, causing serious decline in vision and obscuring things. Expert analysis pointed out that the "culprit" that causes children's blurred vision is actually TV Blu-ray. The British "Daily Mail" also quoted the study of "Conptons University" in Madrid, Spain, saying that if it is exposed to the blue light of LED (light-emitting diode) lamps for a long time, it may cause irresistible retinal cells to the eyes. hurt……
Blu-ray is really so terrible? With such questions, we went to the China National Institute of Standardization's Visual Health and Safety Protection Laboratory to understand the truth about Blu-ray hazards.
What is Blu-ray?
"The light of nature is composed of spectra of different colors. Different wavelengths visually show different colors, such as light with a wavelength of 600-700 nm. We see red light, 500-600 nm. Light, we see yellow light, blue light is between 400-500 nm wavelength," said Cai Jianqi, director of the Visual Health and Safety Protection Laboratory of China National Institute of Standardization.
Physical studies have shown that the shorter the wavelength, the higher the energy and the stronger the penetrating power. Cai Jianqi explained: "As a result, people will pay special attention to the harm of blue light to the human eye." In recent years, LED light sources and various types of computers, mobile phones, television screens, etc., which use LEDs as illumination sources, have peak spectrum of their light sources. This is short-wave blue light. “Now people are getting more and more exposed to these electronic products, so they are more concerned about the impact of Blu-ray on the human eye.â€
Can Blu-ray really cause blindness?
In 2014, the China National Institute of Standardization's Visual Health Laboratory and the Retinal Regeneration Medical Research Group led by Prof. Jin Bing of Wenzhou Medical University conducted a special cell molecular experiment on the retinal damage of blue LED light sources. The experimental results show that the peak spectrum of blue light is in the range of 400-440 nm, and the illuminance is within 500 lx (lux, which is the unit of illuminance). For more than 2 hours, the cell viability will decrease significantly or even apoptosis. The blue peak spectrum is 460- In the 500-nanometer range, the illuminance exceeds 1500 lx and above, and continuous direct exposure for more than 3 hours will result in a significant decrease in cell viability and apoptosis.
"Because the peak spectrum of the current regular LED light source is basically in the range of 450-470 nanometers, the illumination of the conventional light environment generally does not exceed 600lx, and the LED lighting fixtures will be structurally packaged outside the LED light source, LED TV, mobile phone, computer The screens are all back-illuminated or side-lit, so it can be said that most of the LED lighting fixtures and LED displays produced by regular manufacturers do not cause blue light damage, which means that blue light will not cause damage to the retina," said Cai Jianqi. The spotlighting of LED lighting products by the Shanghai Times Light Detection Center during the same period also confirmed this view.
According to the survey, there are no news, reports, statements and warnings related to Blu-ray blindness on the official website of WHO. Even the organization of “Eyes Eye Association†does not exist in WHO. The recent information about blue-light blindness was first announced in August 2010 by a company that made computer protective glasses (film) in Guangdong, China. At the time, the article stated that "computer radiation" is harmful to the human eye and is equipped with theoretical analysis and research. Continue to look down, you will find that these news are to promote the so-called computer radiation protection glasses. In 2012, the page replaced the words "computer radiation" with "blue radiation", and other content did not appear on the major network platforms. Is blue-light radiation blinding the use of the Internet to spread false information, the purpose is to promote related anti-Blu-ray products? Cai Jianqi said that this possibility is not ruled out.
What effect does Blu-ray have on the human eye?
Although blue light does not cause damage to the retina, Cai Jianqi said that blue light may still have three effects on the human eye.
"The first is to cause an increase in visual fatigue." Cai Jianqi said. He introduced that from 2013 to 2014, the Visual Health Laboratory of China National Institute of Standardization conducted a study on the effects of LED blue light on human visual fatigue. The results of human visual physiology experiments of nearly 600 people showed that color vision deviation did not occur in human eyes. On the basis of the visual fatigue of the subjects who used 15% of the blue light fixtures and display products, the visual fatigue of the subjects who were not shielded from blue light was nearly 21% lower. "Therefore, the high blue content may cause an increase in visual fatigue," said Cai Jianqi.
The second is the possible impact on the physiological development of the eye. From 2013 to 2014, the Eye Otolaryngology Hospital of Fudan University and the Visual Health Laboratory of China National Institute of Standardization jointly conducted an animal experiment on the physiological development of blue eyes in rats. Experiments have shown that blue light has the effect of inhibiting the appearance of myopia in mice. "Although the results of animal experiments have not been proven to reduce the effects of myopia on people, it is possible to determine that blue light may affect the physiological development of the eye."
The third is long-term operation in such a light environment, the possibility of inducing macular degeneration in the elderly will increase, but at present this is only based on the data of epidemiological investigations, there is no specific experimental basis as a valid evidence.
Learn about Blu-ray, we have to have our own database.
Cai Jianqi and his research and development team have carried out cross-disciplinary and interdisciplinary special research on light health for more than 4 years. The results of visual human factors test in more than 8,000 Chinese people in different light environments show that it is suitable for Chinese human eye characteristics. The requirements of the light environment are quite different from those of the light environment suitable for Europeans and Americans. “Chinese people have an average pupil size of 3-5 mm, and Europeans and Americans average 6-8 mm. Our skin pigmentation is higher than that of Europeans and Americans. Lightfastness is stronger than that of Europeans and Americans... These physiological differences also determine our visual health. And eye protection is different from Europeans and Americans," he said. "But at this stage, the international lighting and display industries use the physiological characteristics of European and American races as examples in light source design and lighting design, accounting for nearly four points in the world. One of the population of China has no data to rely on, so our various standards can only be based on the physiological characteristics of European and American races, and the Chinese race is actually in the eye structure and light tolerance with the European and American races. Large physiological differences, so the construction of a physiological multi-parameter database based on the characteristics of the Chinese people's eyeballs, and the application of its indicators to relevant national standards, is not only the need to effectively improve the health quality of Chinese people, but also the need to effectively make up for the shortcomings of current international standards. â€
Cai Jianqi said: "At present, our research team is gradually improving the visual health and comfort evaluation technology of luminescent products, developing molecular mechanism research on the effects of light on human eye cells, intervention of gene or protein molecules and prevention and treatment research, and accelerating the construction of the eyes of Chinese people. Based on the function-based physiological multi-parameter database, accelerate the construction of the standardization system in the light health field, and promote the technological transformation and industrial application of light health research results."
"The use of Blu-ray hazards to promote various types of protective products has frequently spread the news, directly affecting the benign development of LED products and even the LED industry. Only relevant research work can be kept up as soon as possible, and China's LED industry can occupy the strategic high ground of the next generation of people-oriented smart technology. Therefore, research on light health has extremely important strategic significance." Cai Jianqi said.
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