LED lighting has gradually penetrated into people's daily lives, and its development prospects are unanimously optimistic. At the same time that people expect explosive growth in the industry, more and more people are beginning to notice the light quality problems affecting the development of the LED lighting industry. What is the impact of LED lighting on people? What are the factors affecting the promotion of LED lighting at this stage? What are the main issues facing global standards development? To this end, we interviewed the board of directors of the ISA (International Semiconductor Lighting Alliance), the honorary professor of the University of Sydney, Australia, and the former vice chairman of the International Lighting Commission, Mr. Warren Julian. His main focus is on lighting research and lighting design and its impact on people. He has just received the Australian Government's Medal of Honor for his great contribution to lighting research.

LED lighting may have an impact on human physiology and mental physics

Reporter: The general lighting field is the largest market for LED in the future. As far as the current LED technology is concerned, people are paying more and more attention to the impact of LED lighting on people. How do you view this problem?

Warren Julian: There are two main aspects to the impact of LED lighting on people. First, high brightness can be harmful to the eyes, especially blue LEDs and white LEDs made with blue LEDs and yellow phosphors. This is because the nodes that emit light are very small, and in order to achieve high light efficiency, people will make the LEDs very bright. The children are more curious if they stare at the light source and are more harmful to the eyes. The French Workplace Health Department has raised concerns about the matter, but I am not quite sure about the official results.

Second, using LEDs as wall washers or handrails, light can be reflected directly or indirectly into the human eye, causing people to see each LED point source. The dot pattern can cause nausea and can even cause paralysis in some people. This problem is caused by the distance between the spots, so good design is very important. I found this problem at the Shanghai World Expo. There are also some buildings decorated with LEDs on the edge of the Huangpu River.

The above mentions the physiological effects (eyes) of LED lighting on people and the psychophysical effects (痉挛 or extremely uncomfortable glare) on some people. These problems will be solved, but designers need to know more clearly the unique problems and advantages of LEDs and gain more experience.

The above is the negative effect of LED, and its front effect is similar to other light sources.

It may take years for LEDs to replace tubular fluorescent lamps

Reporter: What do you think of people's attitudes in different areas such as indoor lighting, outdoor lighting, and decorative lighting?

Warren Julian: At present, LED lamps are still more expensive than traditional light source lamps, and some indoor lighting customers (such as owners) are worried that new LED products (unconfirmed) will cause maintenance problems. In terms of decorative lighting, it is usually replaced in a few years, so its life and cost are not very important. In outdoor lighting, people are equally concerned about maintenance problems caused by LEDs or drives, because the labor costs of maintenance are extremely high.

Reporter: At present, most of the LEDs are used in the market to promote LEDs. What do you think of the current replacement lamps?

Warren Julian: I think alternative lights are not a long-term solution, and new types of fixtures will definitely emerge. The new luminaire will give full play to the advantages of LED. Currently, there are mainly downlights and wall washers under development. It can take several years for LEDs to replace tubular fluorescent lamps for two reasons: one is the poor diffusion of LED light, and the other is because LEDs are very small, high brightness can cause glare, and the brightness of the lamps needs to be reduced to avoid seeing the point source. If these two issues are well resolved, LEDs will replace tubular fluorescent lamps in offices and other venues. The time when the LED enters a large space such as a factory will be later, because replacing the high-power illumination, such as a 400W metal halide lamp, requires a lot of LEDs to be realized, and current technologies such as heat dissipation have yet to be developed.