An LED is a light-emitting diode. This is a semiconductor device which gives off light when an electric current is passed through it. Although LEDs have been in use for more than half a century it is only recently that they have come into greater use because they are energy-efficient and last much longer than more traditional forms of lighting. Today’s LEDs emit white light (all colors of the spectrum mixed together) or individual colors such as red, green, and blue. Modern LEDs are used extensively in TV sets, smartphones, and other digital devices as they are able to turn on and off very rapidly allowing for crisp digital displays. Their efficiency comes with a price. This article looks at LEDs and why you cannot sleep!
An LED is manufactured from substances like gallium, boron oxide, gold, silver compounds, and phosphor. The exact mix of elements determines the color of light emitted when electricity is applied to the diode. People have been familiar with LEDs as red, green, yellow, and blue indicator lights for years. Today the mix of colors emitted by LEDs allows them to be used in digital device screens. The fact that the colors can be switched on and off rapidly makes this use possible. The fact that light is created by passing electricity through the diode instead of heating it up (like an incandescent bulb) allows a lot of these to be packed into a small space, like the computer tablet or smartphone screen! And, the fact that they are energy-efficient means that we will see more and more of these in our lives. And we are already seeing a host of problems like digital eye strain and computer vision syndrome.
These devices are also high energy in terms of the wavelengths of light that they produce. Here is where we get into the nature of LEDs and why you cannot sleep!
Humans naturally spend part of each 24 hour period asleep. We may think that this is a time when the mind and body simply shut down, but such is not the case. During sleep, the body and mind work actively to restore and strengthen. And when we sleep, the brain consolidates memory from the previous day in a process of processing short term memories and storing them as long term memories. In addition, after a decent night of sleep, people are better able to accomplish memory tasks and retain new information. In short, sleep is important. It is part of our circadian rhythm.
Part of how the body manages this cycle has to do with light. For virtually all of human history, this was sunlight. Although sunlight contains all of the colors, it is the colors on the blue end of the spectrum that are more energetic and play the strongest role. This role is the turning on an off of a substance called melatonin which the brain secretes at night when it is dark and which helps us sleep.
In the morning, sunlight and especially the blue light in sunlight, turns off the secretion of melatonin. At night the absence of blue light from sunlight is gone. Our brains secrete melatonin and we sleep. At least that is how it was for thousands upon thousands of years. Even when we had campfires, fireplaces, whale oil lamps, kerosene lamps, and incandescent light bulbs, none of these gave us light that was rich on the blue end of the visual spectrum.
And then we invented LEDs, made them create white light with a heavy dose of blue, and put them in devices that we stare at until all hours of the night!
There is a significant incidence of sleep disorders stemming from the use of digital devices late in the day. We could, of course, go back to incandescent bulbs or even kerosene lamps. But, that is not likely to happen. And society will not give up the energy-efficiency of the many applications of LEDs. Computers and other digital devices are great additions to our lives, putting information at our fingertips and putting us in touch with friends living far away.
There are a couple of simple solutions to LEDs and why you cannot sleep. First of all, forego the use of these devices for two or three hours prior to bedtime. Second, you can protect your eyes and protect your child’s eyes with blue light glasses.
Not only will protective lenses help keep digital device blue light from interfering with the waking and sleeping cycle but they also help prevent eye strain from computer use. Follow this link for more information about protective lenses for blue light.
Too much blue light exposure causes sleep disorders and can result in long term eye damage. Use blue light filter glasses eye protection for your child’s eyes.
Digital display screens emitting blue light are a part of our everyday life. Why should you worry about blue light and your child’s vision?
Children who use digital devices in the hours before bedtime can experience trouble sleeping. How can blue light glasses protect your child’s eyes from this?
Maybe it is the video games late in the evening that are keeping your kids from sleeping at night.
We do all we can to protect our children as they grow up. But, sometimes the dangers they face, like blue light, are not obvious.