Is LED eye protection desk lamp a "pseudo concept"?
The latest market information shows that there are many new "eye protection lamps" with various auxiliary functions: cameras, infrared rays, negative ions, WIFI, electronic calendars, calculators... Of course, the price ranges from tens of yuan to several thousand yuan. Wait, that's a huge difference.
Although the "eye protection lamp" has not been launched for a short time, there has been no relevant national standards and norms, and the market is actually a bit chaotic.
Search for "eye protection lamps" on the e-commerce platform, and nine out of ten merchants will introduce the eye protection functions of their lamps with terms such as "no stroboscopic, blue light removal, wide color temperature", and whether these functions can reduce eye damage. , How different is it compared with ordinary desk lamps, is it a "pseudo concept"? The editor is determined to investigate again for children and parents.
Concept 1. Flicker-free: A light that won't "blind" the eyes?
The mayor found that it is true that people were "blinded" by lights, and the constantly flashing lights are very harmful to the eyes, and "flash" refers to "stroboscopic".
The stroboscopic score is high and low. In Hong Kong-made ghost films, the lights flicker on and off, and the frequency of the lights flickers is very slow. This is the phenomenon of low frequency flicker. Low-frequency flashing lights will interfere with people's visual images, make people's eyes tired and tense, and cause invisible pressure to people's psychology. As a result, the "high-frequency strobe light" that increases the stroboscopic frequency came into being, and the human eye cannot perceive the speed of the stroboscopic light, which improves comfort.
However, the claim that high-frequency flash can make people's eyes comfortable and protect the eyes is only based on theory, and there is no large-scale human experiment to confirm it.
Generally speaking, improving the strobe is one of the ways to improve the desk lamp. However, studying under the high-frequency strobe light for a long time will also cause fatigue, which is not related to "eye protection".
In the market, merchants cleverly renamed "high frequency flicker" to "no flicker", which means the light no longer flickers to and fro. "No flicker" is one of the selling points of eye protection lamps. However, based on the fact that my country's households use alternating current, the strobe will not "disappear".
In the store, the desk lamp salesman recommends that you use the mobile phone camera to detect the stroboscopic condition of a desk lamp, that is, turn on the mobile phone camera and aim at the light bulb. If there are fluctuating streaks on the phone screen, it means that there is a stroboscopic problem. If there are no streaks, it does not exist. Strobe.
Qualified LED lights that have passed the EMC (Electromagnetic Compatibility) design requirements, no flickering stripes can be seen under the mobile phone camera. In addition to the different photosensitive elements of the mobile phone camera itself, the sensitivity of the captured lights is also different. It can only be said that using the mobile phone camera detection method to take pictures with streaks and flickering is definitely not a good light, otherwise it is not necessarily a high-frequency flash.
▲Using the mobile phone camera to detect the stroboscopic condition of the light bulb, there is stripe flickering, and there is a stroboscopic problem, but the method is not rigorous.
Concept 2. No blue light: a desk lamp that does not hurt the eyes?
Filtering out the blue light of desk lamps is also one of the selling points of eye protection lamps. What is blue light?
The sun's rays diffuse through the thick clouds to the ground, blocking most of the blue light. Blue light is a kind of light closest to ultraviolet light, and its energy is huge. Prolonged exposure to blue light can cause the pupil to absorb too much energy, causing macular degeneration in the eye. At the same time, blue light is also a kind of short wave, this kind of light falls in front of the retina, and the eyes will find it difficult to "see" for a long time.
▲Blue light is light with a wavelength between 400nm and 480nm. It has extremely high energy and can penetrate the lens and reach the retina.
Since yellow and blue are complementary colors in the spectrum, and yellow can filter out blue light, merchants have created a series of anti-blue light products, such as anti-blue light glasses, anti-blue light electronic films, anti-blue light displays, etc. The Night Shift setting of the iPhone is the The display is tuned to a warmer tone to reduce the stinging effect of blue light on the eyes.
But blue light is not a monster, it is a member of the full spectrum, and the reduction of blue light will make it appear less bright. Light is a basic life experience for people to gain self-confidence and courage. As the blue light that can brighten the color rendering of the light source, it is very important to our mental health and physical work and rest.
Blue light can be seen everywhere in daily life. In order to make the luminous body whiter and brighter, a large amount of blue light is retained in the background light (artificial light source) of many LEDs, computers and other equipment, and light-emitting lamps are no exception. The harmful blue light we are exposed to mainly comes from LED lights - most LED lights are blue light chips, but "to talk about toxicity without dose is a hooligan", the correct use of qualified lighting is safe for the human eye.
In the market, merchants seize the psychology of people's lack of understanding of blue light and promote their own "eye protection lamps" without blue light, but if a table lamp "does not hurt the eyes", a large amount of blue light is filtered regardless of the color rendering of the light source, and people are in a daze. Is it possible to study well under the pure yellow warm light table lamp that is sleepy? And for light sources such as LED, blue light cannot be filtered 100 percent , but the proportion of blue light is reduced and the harm of blue light is reduced.
