Current positions: Member of International Electrotechnical Commission IEC62386 series standard development project team, International IECEE-CB China counterpart expert group-member, National Ministry of Science and Technology, National Certification and Accreditation Committee lighting expert group-expert, Guangdong AQSIQ defective product management center Deputy Director of the Center, Deputy Director of the Defective Product Management Center of the Guangdong Provincial Quality Supervision Bureau, Deputy Director of the Electrical Department of the Guangdong Product Quality Supervision and Inspection Institute, Secretary General of the Guangdong Provincial Lighting Institute.
2017-12-27 WeChat public number "Cytotechnics" issued by CCTV CCTV2 video invited Beijing Tongren Hospital Ophthalmology attending physician to explain Blu-ray hazards, background video with a variety of LED lamps and text display: "LED lights will hurt the eyes?". There are many low-level mistakes and one-sided views that can easily mislead consumers. In this paper, we point out that we must use audio and video to listen to! (If there is any objection or suggestion to the author's opinion in this article, you can contact the author directly to enter the group dialogue.)
1. CCTV video and ophthalmological attending physicians' speeches have appeared many low-level errors including ophthalmology
1) One of the errors
The doctor explained that "the lens", however, mistakenly points to the "ciliary body" and the picture is also wrongly suggested as "ciliary body" (see CCTV video screenshot 1 below the flashing small blue circle).
The author states that the function of the "lens" is to provide visible light, including blue light, into the fundus of the eye, and the more important function is as a lens to focus the visible light to reach the retina to get a clear image of the object, which is directly related to the damage of the retina blue light; The "ciliary body" is a soft tissue mechanism used to adjust the focusing function of the lens "lens" (CCTV video screenshot 1 is "Crystal Skull") and is not directly related to the blue light of the retina.
2) Error 2
The doctor explained and provided a schematic diagram of the longitudinal section of the eye. Its "macular spot" position was painted on the center of the CCTV video screenshot 1.
The author states that the correct "macular spot" should be located directly on the visual axis and the pupil in the fundus slightly above the optic disc (see online collection of schematic diagrams 1, 2 and 3). Although the diagram allows exaggeration, it deviates too much and does not do anything. The explanation will inevitably make people even wonder if their medical profession is professional.
3) Error 3
Physician explained: "Long-wave ultraviolet, short-wave ultraviolet" at the same time the video map shows only "long-wave UV-A" and "UV-UV-UV", while the figure does not appear "short-wave UV-C". (See CCTV Video Screenshot 2)
The author states: The ultraviolet rays that are usually present in the atmosphere are classified into: UV-A (13-15 nm to 400 nm) UV-A (makes the skin dark spots and causes fluorescent effects); 2280 nm to 315 nm Ultraviolet-UV (UV-B) causes erythema to cause skin redness. In the past, miners who did not touch the sun for a long time needed to irradiate a certain amount of ultraviolet radiation in this band, sometimes called healthy ultraviolet rays, but also had a bactericidal effect. But it was precisely the same as the human body. Ultraviolet rays with the greatest skin and eye damage can cause injury in a short time and at low doses; UV-C (shortly UV light) from 3200 nm to 280 nm (mainly used for sterilization, of course, is also very harmful to human skin and eyes).
4) Error 4
Physician commentary said: "Because of the strong blue light energy, it can penetrate all structures and go through the fundus."
The author explains: 1 In fact, the wavelength of ultraviolet light, especially short-wave ultraviolet light, is far shorter than that of blue light. Therefore, the ultraviolet energy is also greater than or far greater than blue light. Ultraviolet rays do not reach the fundus is not the cause of energy, but is absorbed by the front of the cornea and other tissues and will cause some damage. Ultraviolet rays are invisible and intangible. Small doses of medium-wave and short-wave ultraviolet rays can cause eye and skin damage. Generally speaking, they are more harmful than blue light, but people do not have frequent contact and dose problems like visible light such as blue light. Not noticeable. 2Blu-ray can be directly through the fundus. It also shows that the cornea, lens, vitreous and other tissues that it passes through are not absorbed by it, resulting in less reaction, which means that blue light does less harm to them.
5) Error 5 (inconsistent with international national consensus standards)
Physician commentary said: "The shorter the blue wavelength, the greater the damage, because the shorter the wavelength, the stronger its energy."
The author states that the shorter the wavelength is, the stronger its energy is, but the shorter the blue wavelength is, the greater the damage will be. This is equivalent to the national standard GB/T20145-2006 "Photobiosafety of Lamps and Lamps System" (equivalent to The conclusions of the use of the International Commission on Illumination CIES 009/E:2002 and the International Electrotechnical Commission's International Standard IEC 62471) are inconsistent. This standard summarizes the results of many medical studies and lists in Appendix A the special study of UV, visible, and infrared light. The key reference index for various injuries. The standard states that the maximum blue wavelengths of blue light damage are 435 nm to 440 nm, which are located in the middle of the main wavelength range of blue light damage 400 nm to 500 nm, and are not the shortest and highest energy wavelengths in the blue light range.
6) No basis for exaggeration
Physician commentary said: "What I just said is a type 1 hazard. There are many high-intensity spotlights and searchlights in danger that fall into category 2 and category 3, and vision is lost in an instant and is irreversible."
The author explains: According to the international national consensus standard 1 most of the LED lighting products are now very safe class 0 non-hazardous levels, and therefore international national standards do not require warnings to be posted on their products. For example, there are household LED lights and lamps with frosted screens. You see only the light emitting surface and you don't see a single light emitting point. These lights can continuously stare at the light emitting surface for 2 to 3 hours without damaging the eyes due to blue light. 2 Currently There are many types of LED lighting products that are Class 1 (low hazard) hazards. For example, some non-condensing products that can directly see the LED's luminous points do not require warnings and are also safe. They can stare continuously at the luminous point for 100 seconds. Above will not hurt the eyes due to blue light. 3 Even if a small amount of luminaires meet Class 2 hazards (moderate hazards), the standard requirement is to indicate the threshold (critical) distance on the luminaires based on the measurement results. It is a medium hazard within this distance. Warning Do not stare at the light source continuously for 0.25 to 100 seconds. (in the distance from the lamp); outside this threshold (critical) distance, it still belongs to Category 1 (low hazard) and is safe. According to the national international standards, human eyes watch 3 kinds of high-harm products 0.25 seconds cause permanent harm; 43 high-risk LEDs are not allowed to be used for lighting products such as lamps and lamps, but also described in the above international national standards, in reality The lights and luminaires are extremely unlikely to achieve Class 3 high hazard levels. For example, as a comparison, the brightness of the sun is very high, about 4X109 cd/m2, which is hundreds, thousands or tens of thousands of times the surface brightness of conventional lamps and luminaires. The human eye can continuously see the sun light for no more than 1 second without harm. However, the sun is still only close to reaching the RG3 high hazard class. Only many types of lasers can achieve Class 3 high hazards.
2. About the case of blindness caused by lamps of CCTV video hosts
After searching on the Internet, one case of a baby bathing blindness was reported, but the lamp was a bathroom heater lamp for bathing and heating, that is, an infrared light bulb, and no case of LED blindness was reported.
Online search injury cases: 1 baby bath to see the bathroom heater infrared light bulb caused blindness. 2 Photographs led to blindness in the baby. 3Laser pens and other laser products hurt and blind.
3. Errors in the distribution of the public account outside the video of "Cell Division Medical Exam"
Dispatch: "A major source of cataracts is high-frequency blue radiation."
The author states: According to the national standards and the International Electrotechnical Commission standards and the International Commission on Illumination "Light bio-security of the lamp and lamp system," Appendix A "Biological effects summary", it mentioned that "cataracts" mainly by high-calorie infrared As a result, it is often referred to as "thermal radiation-induced cataracts", "cataract cataracts" or "glassy cataracts"; it also mentions "cataracts" caused by ultraviolet light at 290 nm-400 nm and long-wave ultraviolet light; And provided some "key references." However, it did not mention that Blu-ray can cause "cataracts." Therefore, even though Blu-ray may cause a slight "cataract," it is certainly not the root cause.
Recommendations for the purchase and use of LED lamps
1) At present, white LED lighting products do not contain ultraviolet and infrared rays. Compared with traditional lighting products and the sun, the first current LED lighting products do not have medium-wave and long-wave ultraviolet rays and infrared rays, which are less likely to cause cataracts, and LED lighting products do not harm large-scale short-wave ultraviolet rays; secondly, in terms of blue light damage , Sunlight and some traditional lighting products also contain a large amount of rich blue light components, including the relative damage of the largest 435nm ~ 440nm blue light, therefore, there is no need to talk about the "blue light hazard" of LED lighting products.
2) When the consumer chooses the home LED lighting product, it is best to use the surface light type with a frosted screen; it is best to use the soft light with warm colors, not the color is too white; the best in the home is not to install the condenser shot Lights.
3) Of course, we still have to avoid staring at the light of LED lamps and lamps for a long time. We must also avoid staring at traditional lamps and lamps and any glowing or heating objects. We must especially monitor infants and young children because of the above national standards. The standards of the International Electrotechnical Commission and the International Commission on Illumination are directed at adults and do not consider infants and young children. The eyes of infants and toddlers are not shaped and are much more fragile than adults.