What Is Blue Light? A Complete Scientific Guide

Blue light is part of the electromagnetic spectrum that humans can see. Blue light has a wavelength between 500 and 380 nanometers, making it the most potent and shortest-lasting frequency.

About a third of the visible light spectrum is made up of blue light. Most of the time, the blue light comes from the sun. Fluorescent light bulbs, LED TVs and computer screens, mobile phones, and tablets all give off blue light, but humans make it all.

Although it is often associated with electronic equipment, the sun is the most significant supply of blue-colored light. The lighting options include CFLs, regular fluorescents, as well as LEDs. The amount of blue light produced by screens is significantly less than that produced by the sun. It's also more secure than the blue light naturally visible in the sun.

Growths, cataracts, and eye cancers are just three conditions that may be caused by exposure to UV radiation. When compared to other colors, blue light is one we need more information about. The research into its consequences continues.

Does Blue Light Make you Healthier?

Researchers have found that blue light makes people more alert, improves brain function and memory, and makes them happier. In a way, it controls whether you feel alert or sleepy, whether you are aware of it or not (circadian cycle). Young children also benefit from being in the light because it helps their eyes and vision grow.

How bad is it to be in blue light?

Compared to being outside in the sun, screens only give off a small amount of blue light. But there are worries about the long-term effects of spending too much time in front of screens. This is especially true when screens are too close and right in front of the eyes for long periods.

80% of American adults use digital devices for more than 2 hours daily. About 77% of them use more than one device simultaneously. More than half of the people who use computers have some digital eye stress.

Blue light is hard for our eyes to block, so almost all of it gets through the lens and cornea to the retina, turning light into an image the brain can understand.

If you are exposed to blue light for a long time, it could hurt the cells in your retina. This could lead to macular degeneration and other vision problems as you age. It is also linked to eye cancer, cataracts, and growths on the cornea, which is the clear cover that protects the whites of the eye. A study on eye health and vision by the National Eye Institute found that children's eyes are much more likely to be hurt by the blue light that electronic devices give off than adults' eyes.

When using a digital device, the person is likely to blink less, which could lead to dry eyes and more pressure on the eye. When you strain your eyes, they can become irritable, and headaches and shoulder and neck pain are also common. The Vision Council says that 27% to 35% of adults in the U.S. have had at least one of these symptoms when using electronic devices.

How blue light affects the ability to fall asleep?

Even though there are a lot of studies about blue glasses, there is yet to be a clear answer. But they can lessen the effect that blue light has on the eyes. Those who need to spend a considerable time in front of a computer screen can ease the strain on their eyes by wearing glasses that block blue light. Blue-light-blocking glasses worn during the day have been shown to help people get to sleep, stay asleep, and get better sleep. Blue-light-filtering lenses can reduce harmful effects by 10–23% without affecting the quality of the image. Lenses with yellow tints can help people who use digital devices for long periods feel more comfortable.

The amount of blue light determines when our bodies begin producing melatonin. As a result of this, avoiding blue light in the hours leading up to bedtime may also result in an improvement in the quality of sleep. The most prevalent diseases, including type 2 diabetes, cancer, heart disease, sleep disorders, and cognitive issues, might be brought on by disrupting the circadian rhythm. Hence, to have a sound sleep, avoiding using electronic devices such as mobile and laptop before going to bed is better.

Use glasses that block blue light

It has been shown that protecting your eyes from blue light during the day can help with the process's onset, maintenance, and quality. Blue light hurts the eyes, but generic lenses that block the blue wavelength could reduce the damage by 10–23% without lowering the quality. Putting yellow lenses on your computer screen can make it easier to look at it for long periods.

You can put a blue-light filter on your phone, tablet, and computer. The filters, which stop most of the blue light that would otherwise get into your eyes, don't change how clear the screen is.


The portion of the electromagnetic spectrum that seems blue is indeed present in natural settings. The sun is the primary source of most of the blue light you see. However, some specialists in the field of medicine believe that exposure to blue light from artificial sources can harm the eyes. Experiments on animals have demonstrated that exposure to blue light damages cellular health. Not much data suggests that the blue light emitted by electronic devices such as tablets, smartphones, and LED televisions harms people's eyes.

However, if you are required to sit in front of a computer for an extended period for school or work, you should take frequent rests to prevent your eyes from becoming weary. If you use electronic devices at night, turn them into the amber light mode or put them away at least an hour before you sleep. It has been demonstrated that exposure to blue light disrupts the body's natural sleep-wake cycle.

Updated on: 14-Feb-2023


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