As a new type of lighting equipment, LED lights have been widely used, and the trend of replacing other light sources is becoming more and more obvious. But it is undeniable that as far as the current technology is concerned, stroboscopic LED lamps are common. So, how do we ordinary people solve the stroboscopic problem?
First of all, what is the strobe of a lamp?
According to tBaidu Encyclopedia's explanation, stroboscopic means looking at the screen of one electrical appliance on the screen of another electrical appliance. On the screen of the other electrical appliance, a bright line will move from the bottom to the top of the screen, and then appear from the bottom again. If this goes on indefinitely, it gives us the feeling that the image is flickering.
Art lamp with LED light source installed
This explanation in the encyclopedia is too technical. Zhihu author: Shrugged The author thinks the definition of stroboscopic is relatively easy to understand: stroboscopic, flickering with frequency, and the rapid and repeated changes of light over time are called stroboscopic, directly The feeling is that the image is jumping and unstable.
Second, to what extent do LD lamps/light sources flicker and have an impact on our human body?
Most people can perceive strobes below 50 or 60 Hz. When the frequency reaches a certain level, the human eye will regard the flickering light as a continuous source. This frequency is called the "critical flicker frequency" (CCF).
CCF varies from person to person and in different situations for the same person, but most people have CCF values that do not exceed 100 Hz. Many people feel very uncomfortable when faced with strobes below 50/60 Hz, and some people are still uncomfortable between 50-100 Hz. So what frequency is needed to eliminate this effect? It varies from person to person, some say 160 Hz, 200 Hz, and some say 500 Hz, but the industry believes that there is no problem if it reaches kilohertz (KHz).
Small LED chandelier
Third, what are the hazards of LED lamps/light source stroboscopic
Studies have shown that varying degrees of stroboscopic effects on people's physiology and psychology, of course, are mostly negative, such as damaging vision, irritability, and inducing epilepsy. for example:
1. For sports venues that require lighting at night, such as billiards halls, table tennis halls, badminton halls, tennis halls, etc., the sports balls cannot be seen clearly due to flickering lights;
2. When taking photos and videos, if you use flashing lights, it will be impossible to avoid dark areas during photography and black scroll bars when filming;
3. Including strain fatigue, eye fatigue, blurred vision, migraine and vision loss;
4. The effect of low-fluctuation high-frequency flashing is not obvious, and migraine or severe headache may occur within a few minutes, often accompanied by symptoms such as nausea and visual disturbance;
Fourth, the reasons why LED lamps/light sources flicker
Most light sources have stroboscopic effects, but the degree varies. LED stroboscopic is largely not a problem with the LED chip itself, but comes from the driving and dimming components. Common causes of stroboscopic are:
1. Inferior driving components cannot reduce the "voltage and current output ripples" generated in the process of "converting from AC to DC" and from the driving components to the LED chip.
1. Inferior quality dimming components, either poor compatibility, or using low-frequency PWM dimming.
Fifth, are there any LED lamps/light sources that do not flicker?
It is impossible to be flicker-free in an absolute sense. The Chinese industry standard’s flicker requirement for qualified products is 3125Hz. From a professional point of view, the exact name of "no stroboscopic" is "imperceptible stroboscopic". According to the "stroboscopic" requirements of the China Quality Certification Center for reading and writing desk lamps, "fluctuation depth" is a measure of the "stroboscopic" of desk lamps. ” standard value.
LED lamp beads, patches
Take table lamps as an example. The national standard requires that the fluctuation depth of table lamps be less than 3.2% to be qualified. However, it turns out that many so-called "eye protection table lamps" on the market have fluctuation depths of more than 3.2%, which means that most of them do not "protect the eyes". Eyes".
Finally, what should we ordinary consumers do when faced with strobe?
As mentioned before, there are currently no lamps that are flicker-free, so we can only choose lamps with flicker within the acceptable range as much as possible.
1. It is recommended not to buy low-priced and low-quality LED products without any three certificates. Try to buy regular brand lamps and light sources.
2. Try to purchase lamps and light sources certified by the China Quality Certification Center (CQC).
3. The daylight lighting system can be used to introduce outdoor natural light into the room. After the natural light is processed by the system, it will not only be flicker-free and will not cause harm to human eyes, but will also block most of the ultraviolet and infrared rays. The light will be soft, the illumination is uniform, warm and comfortable. , let us bathe in natural light with peace of mind and return to nature.
Postscript: Lighting design is not about choosing lamps. It is a job that is both technical and artistic. If you really don’t have the time and expertise, you can consult recolux for free.