With a foreign media report that “a junior high school student used eye protection for one month, myopia degree increased by 250 degrees” and was forwarded by Weibo, some hospitals in Shanghai asked in an eye clinic that “eye protection will not harm children’s eyesight” The parents of “How to choose eye protection lights” have recently surged. Experts said that uniform and comfortable lighting helps prevent and control myopia, but some businesses have excessively exaggerated the protective effect of eye protection on eyesight and mislead consumers.

Lighting should be uniform and comfortable

In the same situation with the eye, poor lighting can cause eye fatigue, but this is not the most important reason for myopia, eye burden caused by the continued short-term eye is the most important reason for myopia.

After reading the elementary school's Tao Tao, I just received my grandmother's gift - a pair of eye-protection lights. It took only one day before she was taken away by her mother. It turned out that Tao Tao's mother saw the friend's forward "a junior high school students use eye protection lamp for 1 month, myopia degree deepened 250 degrees" microblogging, for fear of eye damage to Tao Tao eyes. According to Ke Bilian, chief ophthalmologist of the Shanghai First People's Hospital and member of the Shanghai Optic and Optics Society, the number of parents who ask about the advantages and disadvantages of the eye lights in the outpatient clinics is particularly large. Even her friends call specifically to ask questions.

Ke Bilian said that China’s current “Health Standards for Lighting and Lighting of Primary and Secondary Schools” stipulates that the average illumination of students’ classrooms should not be less than 150 lux (units of lighting brightness), but there is no uniform standard for home lighting, and “eye protection lights” have no national standards. There is no industry norm. In general, uniform, comfortable lighting helps prevent and control young people's myopia. "Uniform" means no shadow, and the international demand for "uniform illumination" is very high. For example, the Lighting Association of North America encourages teachers to use remote controls to regulate classroom lighting. If it is found that dark corners of some cloudy classrooms are dark, they should be adjusted in time; "comfortable" It is not too bright or too dark.

Lighting prevention of myopia does not fly

"Actually, the strobe of the eye protection lamp is still there, but it only changes from low-frequency flash to high-frequency flash, and it does not feel dazzling."

Zhao Hong, director of the ophthalmology department at Shuguang Hospital, believes that “protecting eyes and protecting myopia with eye protection” is the propaganda of the business. There is no sufficient scientific basis. There is no clinical research on a wide range of samples so far. High-frequency flash light has a protective effect on the eyesight of young people. . The director said that some researchers have used mice to do control experiments, that is, three groups of mice were irradiated with high-frequency flashing lights, fluorescent lamps, and high-intensity gas light. After a while, their retinal apoptosis was observed. Case. "But this animal test does not completely explain the problem. There is a big difference between mouse eyes and human eyes. At present, there are no large-scale clinical studies that show that high-frequency flash light has a protective effect on adolescents' vision."

As an expert in the long-term study of various lamps, Professor Zhao Yufeng, a consultant of the China Indoor Environmental Monitoring Working Committee, believes that it is “difficult to say” whether eye protection lights protect eyesight. The biggest difference between the eye protection lamp and the fluorescent lamp is that it increases the frequency of the oscillation so that the strobe cannot be distinguished by the naked eye. In fact, the strobe of the eye protection lamp still exists.

Professor Zhao said that the strobe, illumination and electromagnetic field intensity are the three criteria for judging the merits of eye protection. A few years ago, he participated in a market survey covering a number of provinces and cities and found that there are few eye lamps with high strobe, soft illumination, and low electromagnetic field intensity. He suggested that when purchasing eye protection, people should pay attention to checking the product's test report and identification certificate, or after turning on the light and observing it to see if its brightness is soft, is it dazzling? Ke Bilian said that the grille lamp is more reflective and more uniform than the grille lamp, and it is relatively easy to cause glare.

Be alert to the misunderstanding of "a lonely lamp"

Although the high-frequency flash eye lamp is not easy to make the human eye have a sense of fatigue, but in the eyes under the light for a long time, the eyes will still be tired, with the eye protection, but also pay attention to the eye rest.

In the evening, Rainbow said that the causes of myopia are very complicated. Apart from genetic factors, it is related to people's living conditions and eye habits. For a long time after birth, the child's eyes are hyperopia. Under normal circumstances, after development, the human eye changes from hyperopia to normal vision at the age of 9-12. In our current learning environment, many children become square when they are 6 years old. After this, the child's vision gradually developed into myopia.

"The reason why it has become so early, is that it has nothing to do with the frequency of lights. The main reason is that children look at things too often at close quarters." Director Zhu pointed out that in addition to watching TV and doing homework for a long time, Electronic devices like IPad are also playing a key role in children’s myopia.

Ke Bilian pointed out that some children and parents now have misunderstandings about the use of eye protection. We must be alert to the fact that some businesses have exaggerated the role of eye-safety lamps and misled parents to think that using eye protection can be done once and for all. Instead, they ignore the overall consideration of rational use of the eye, and even mistakenly think that protecting eyesight is only for this eye protection. When the lights “wow”, they only use “a single light” to illuminate their eyesight.

Ke Bilian suggested that reasonable use of eyes and intermittent use of the eyes, that is, 20 minutes before school, 35 minutes of primary school, 40 to 45 minutes after 13 years of age, and overlooking between classes, can make eyes under the same eye level not too tired; by appropriate Outdoor sports such as table tennis exercise active eye muscles; supplement calcium, magnesium, zinc and other trace elements from a balanced diet; maintain a good read and write posture, punch one foot and one inch; try to play less computer, video games, watch less TV; often Looking far, breaking the space vision limit.

XLPE Insulated Electrical Cable For Rated Voltage 0.6/1kV

1. Product Standard

GB/T12706.1-2002, equivalent to IEC60502

2. Usage

This product is suitable for use in rated AC voltage (U0/U) 0.6/1kV system transmitting and distributing circuit.

3. Property for Use

It is far better than all property targets of PVC Insulated Power Cable and has overcome the shortcomings of physical and chemical cross-linkage, and completely reaches or surpasses GB and IEC technical property value.

The allowed max .cable conductor work temperature is 90℃;urgent excess work temperature is 130℃ for short circuit(5s), max. conductor temperature is 250℃.

The environmental temperature for laying cable should be not less than 0℃. If laying under 0℃, the cable should be preheated.

The cable bend radius for single core should be not less than 12 times of overall cable diameter; for multi-core cable, not less than 10 times of overall cable diameter.

The current-carrying capacity is large and not limited by drop during laying .

4. Type of cable

0.6kv Cable,1kv Cable

Type: YJV, YJLV, YJY, YJLY, YJV22, YJLV22, YJV23, YJLV23, YJV32, YJLV32, YJV33, YJLV33.


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YJLV: Aluminum conductor , XLPE insulated and PVC sheathed Electrical cable

YJY: Copper conductor , XLPE insulated and PE sheathed Electrical cable

YJLY: Aluminum conductor , XLPE insulated and PE sheathed Electrical cable

YJV22: Copper conductor , XLPE insulated, steel tape armored and PVC sheathed Electrical cable

YJLV22: Aluminum conductor , XLPE insulated, steel tape armored and PVC sheathed Electrical cable

YJV23: Copper conductor , XLPE insulated, steel tape armored and PE sheathed Electrical cable

YJLV23: Aluminum conductor , XLPE insulated, steel tape armored and PE sheathed Electrical cable

YJV32: Copper conductor , XLPE insulated, steel wire armored and PVC sheathed Electrical cable

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YJV33: Copper conductor , XLPE insulated, steel wire armored and PE sheathed Electrical cable

YJLV33: Aluminum conductor , XLPE insulated, steel wire armored and PE sheathed Electrical cable


YJV, YJLV, YJY, YJLY: For laying indoors, in tunnels or cable trench, unable to bear external mechanical forces.

YJV22, YJLV22, YJV23, YJLV23: Indoors, tunnels, cable canal, vertically burying and easy to corrode places, can bear mechanical pressure

YJV32, YJLV32, YJV33, YJLV33: Vertically laying, can bear mechanical pulling force, but not pressure.

Low Voltage Power Cable

Four Core Aluminium Conductor,Five Core Copper Conductor,1kv Cable,0.6kv Cable

Huayuan Gaoke Cable Co.,Ltd. , https://www.bjhygkcable.com

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