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Proper use of qualified LED blue light does not hurt the eye
Foreign expert opinion
Long-term use of LEDs may damage the retina
According to the British "Daily Mail" report, Dr. Celia Sánchez-Ram os of Com plutense U ni-versityinM adrid, Spain, showed that due to LED lights The emitted light is a short-wave high-energy light source, which is blue or violet in the visible light spectrum. Exposure to such light for a long time may cause damage to people's retina.
Dr. Kasans Ramons also pointed out that the light radiation emitted by energy-saving lamps can cause serious damage to human retinal pigment epithelial cells. To this end, he suggested that LED lamps should be used as close as possible to lamps such as desk lamps . Try not to look directly at the light source with your eyes, and pay attention to the time of use. Close your eyes every 20-30 minutes and rest for a while.
Ophthalmologist opinion
Blu-ray, high brightness, may hurt the eyes
Lu Jinhua, a senior optometrist and optic optometry expert at the Zhongshan Ophthalmic Center of Sun Yat-Sen University, said that different wavelengths of light have different penetrating power. Lights that are harmful to the eyes are mainly high-energy short-wave light, such as ultraviolet light, blue light, and violet light. The most comfortable thing for the human eye is the medium-wave green light. The blue-violet light penetration is stronger than the short-wave ultraviolet light. The energy in the visible spectrum is relatively high. It can penetrate the cornea and the lens and reach the retina. Once the retina is damaged, it will cause irreversible damage. Therefore, the most important damage to the human eye in nature is the short-wave, relatively high-energy ultraviolet and blue-violet light.
Generally, the LED light has a single light color, high brightness, high color temperature, and may contain more blue light components. "For a cell, if it accepts a high-energy photon, it may cause some damage to its nucleic acids and proteins, causing the entire cell to be fatally threatened."
"I think that the research of the expert in Spain mentioned that the damage of LED to the eyes is mainly directed to the blue component in it. After a long time, it may cause irreparable damage to the retina. This may be reasonable. ."
Lu Jinhua believes that LED lighting may be harmful in two aspects. The first is that the blue light content is more, which damages the retina. The second is that some products are too bright, which will stimulate the eye to constantly adjust and cause eye fatigue.
In addition, LEDs may also form glare. Glare means that the local brightness is too high and is not proportional to the surrounding environment, causing the retina to produce bright and dark areas, resulting in dramatic changes in the pupil. Glare can cause eye irritation and other problems. If the glare phenomenon and the stimulating stimulus are relatively large, it will have a negative impact on the human eyesight. If it is in the blue light hazard and glare phenomenon for a long time, it will add importance to fatigue and damage the optic nerve, especially the visual acuity of young people whose vision has not stabilized for a while.
Lu Jinhua also stressed that on the other hand, LED lamps are the most promising source of energy conservation and environmental protection. "We cannot deny it because of the current state of the art and some inferior products. We must also acknowledge that there are Some of the better quality LEDs, and will continue to improve the process in the future, such as making the color temperature more gentle, reducing the blue light content, the brightness design is more reasonable."
Weapon
Good table lamp nine standards
Color temperature and brightness are important criteria for judging the merits of a table lamp, but only these two indicators are not enough. For example, even if the color temperature is correct, if the method of use is not correct, it may cause an injury accident. Earlier, a baby in Xi'an was blinded by the long-term use of Yuba lights. This case is enough to give us an alarm. Yuba's color temperature is not high, but the power is great, and the baby faces up while facing the light source. Even if the amount of blue light in the Yuba light is very low, the superposition of the comprehensive factors will still cause serious blue light damage, and eventually cause permanent damage to the retina.
Xu Qinghui believes that a good table lamp must withstand these nine standards:
1. Look at the certification: the learning desk lamp must pass the national mandatory CCC certification and it is within the validity period;
2, look at the light color: the warm white light source with a color temperature of 3200 ~ 3500K is most in line with the human eye visual physiology needs;
3, see glare: the eye is 40 cm from the height of the table, the horizontal distance from the desk lamp source is 60 cm, you should not see the direct or refracted light inside the lamp;
4, look at the illumination: the light source from the desktop height of 40 cm illuminance at 750-1000 Lx is the best visual light environment; no instrument? That can only be visually perceived, the desktop is "very bright" feeling right;
5, look at the color: the palm is placed up to 30 cm under the table lamp, the palm line is clear, the skin color is ruddy, it means the table light color is clear, the color reproduction is good; on the contrary, the blur is unclear, the color is dark yellow, the gray is poor;
6, look at the power: LE D lamp should be more than 7W, energy-saving lamps should be more than 11W, tungsten halogen lamps (quartz lamps) should be about 35W (table lamp working time is short, energy-saving is not the main consideration);
7, see strobe: low frequency flashing will cause eye fatigue. Look at the light with your mobile phone camera. There must be strobes with stripes, but there is no need for stripes.
8. Look at the scope: The desk lamp should have a certain height. At this time, the illumination surface is large and the illumination is uniform. The illumination at 40 cm from the desktop should not be lower than 750 Lx;
9, look at the structure: table lamp bracket to have a certain length, easy to stretch and shrink, suitable for computer operations, drawing calligraphy, learning to play piano and other multi-purpose use.