The Harms of Blue Light
Our eyes detect light wavelengths of 400-750 nanometers, and as the wavelengths get shorter, the higher their energy output is. Blue light is the light waves that measure between 400-500 nanometers. The lower on the scale the more harmful these waves are due to the higher amount of energy they give off.
There is blue light that comes naturally from places like the sun and in small doses, at the right time, blue light is not a problem; it is a good thing. When our body detects blue light, it stops creating melatonin, the chemical released to our body to make us sleep, and it prepares us to wake up. It is the source of why on a sunny day we tend to feel happier and more alert than on days that are cloudy. The wavelengths are on the higher end of blue light wavelengths which hit above 460 nm.
The longer wavelength blue light is only good and safe when it is experienced at the right time. We experience these blue light waves when we have our eyes on a screen, but these blue light waves can make relaxing for bed harder. If your body is still receiving those wavelengths, it will delay creating your melatonin which makes it more difficult to fall asleep and sleep peacefully. This is the part of blue light that keeps you up late and why you should distant yourself from a screen at night.
Blue light that is shorter than 430 nm is given off from the back lighting of a digital screen. This light can cause digital eye strain because the light scatters and makes your eyes work harder. Digital eye strain can cause tired eyes, blurred vision, headaches, and other symptoms. For a while carpal-tunnel was the leading computer complaint by workers but over the past couple of years that has changed to digital eye strain due to the abundance of time we spend looking at a screen.
Another problem with blue light is the high energy it emits. This is a factor in damaging people’s vision. Blue light is able to reach the center of the retina and cause damage to those cells. Our body creates a substance known as melanin which protects eyes from blue light and UV rays from the sun, but with age melanin levels decrease. As your melanin levels lower, your eyes become more and more vulnerable which results in more damage done by this light.
There are protective measures to take to decrease the exposure and side effects of blue light. There are filters that can be purchased to put on your phone and computer or blue light glasses. Both options decrease the amount of blue light reaching your eyes. We are surrounded by technology every day; therefore, we need to be aware of harmful effects in order to take the appropriate actions.