Researchers develop new LED bulbs, which are expected to make the bulb emit less blue light
Compared with other types of lighting led, LED light bulb have considerable advantages. Because of their higher efficiency, they require less power to operate. They don’t emit unnecessary heat like old-fashioned incandescent lamps, and the best led lights bulbs even last longer than fluorescent lamps. But LEDs are not without problems. It is suspected that excessive exposure to the blue light produced by today's standard LED light bulbs will cause fatigue, mood disorders and insomnia and other health problems, which linger. In addition, higher prices will prompt buyers to consider other options.
The University of Houston research team led by Jakoah Brgoch, associate professor of chemistry in the School of Natural Sciences and Mathematics and principal investigator at the Texas Superconductivity Center, is developing an bulb light led that uses most of its energy from the safer violet part of the visible light spectrum. Instead of just masking blue light, they are developing a unique class of luminescent materials called phosphors that can absorb the monochromatic emission of violet LEDs and convert the light to cover most of the visible spectrum.
"The luminous body that our group is creating is no longer operated with traditional blue LED chips, but replaced with purple LED chips. This basically shifts from blue to purple as the basic light source, and then converts the purple LED light into us. The broad-spectrum white light seen," Brgoch explained. "The ultimate goal is to make this new violet-based light bulb as energy-efficient as possible, but also very cheap, and ultimately to enable the new lighting technology to be sold to consumers."
Their research results were recently published in the journal ACS Applied Materials and Interface, a well-known academic journal of the American Chemical Society.
But technically speaking, there is actually no pure white light. Take a prism against the bulb, and you will see that its light is divided into different wavelengths, showing a beautiful color band from purple to red; this is the scientist The visible light spectrum. The lamp looks white, because human eyes and brain work together to mix human perception of these independent color bands into white light. At this time, it may be illuminating the words you read. Different types of light bulbs emphasize the visibility of light. Different parts of the spectrum.
The engineers of the lighting company manipulate this balance to create a specific atmosphere. A little more red will produce warm, round white light, which is very suitable in the living room, while cool blue will emit clear white light, which is more suitable for office lighting. But outside the laboratory, the blue tendency of LEDs has always been unavoidable.
"Sometimes you recognize it-the cheapest LED bulbs, sometimes it looks like a nice warm white light. But even among the most expensive bulbs, if it is based on blue LEDs, there are still quite large The blue light component sneaked in," the professor explained. Recently, scientists have been paying attention to how the frequency of light affects health. "With the advent of LED lighting, companies have begun to try to understand how humans interact with light, and more importantly, how light interacts with humans. When you sit in an office, the blue hue in the light is a good thing, because They help you stay refreshed, but the same light may keep you awake at night when you need to rest. This is very bad. In essence, it's about following the natural circadian rhyth m without being disrupted."
Sleep studies have shown that excessive exposure to blue light frequency at night can change hormones such as melatonin, sometimes leading to insomnia, sleep cycle disturbances, and other problems. Excessive blue light exposure is also suspected to be the formation of cataracts. Urban residents living in LED-based street lights, traffic lights, and illuminated commercial signs are also exposed to more LEDs than suburban residents.
"This is not to say that we should remove all blue light from your bulb. You need some blue spectrum. This is not to eliminate blue, but to keep it at a reasonable level. This is our job. What you are pursuing," said Shruti Hariyani, the author of the paper and a graduate research assistant. (Source: cnBeta)
