Given our modern lifestyles, most of us spend the majority of our waking hours staring at a digital screen. Studies suggest that 60% of people spend more than 6 hours a day in front of a digital device. When looking into these screens, our eyes are directly looking into blue light. Sources of blue light include the sun, digital screens (TVs, computers, laptops, smartphones and tablets), electronic devices, and fluorescent and LED lighting. Blue light has a wavelength of between approximately 380nm and 500nm; making it one of the shortest, highest-energy wavelengths. Our eyes’ natural filters do not provide sufficient protection against blue light rays from the sun, let alone the blue light emanating from these devices or from blue light emitted from fluorescent-light tubes. Prolonged exposure to blue light may cause retinal damage and contribute to age-related macular degeneration, which can lead to loss of vision.
Understanding Blue Light
You likely learned in school that the electromagnetic spectrum is not completely visible by the human eye. Ranging from low-energy radio waves to high-energy gamma waves, only a small part of it can be seen by us. The blue light is part of the visible light spectrum. This is the reason why we see the sky and large bodies of water as blue.
Blue Light from the Sun
Sun is the natural source of blue light. We all know that the UV rays from the sun are harmful to the human body. However, the blue light from the sun does have a positive effect on our brain. We are supposed to be active during the day; allowing us to complete our daily tasks. The sun’s blue light naturally activates our brain so we can feel awake, attentive, and energetic. This is also the reason we automatically feel sleepy at night. Sleep experts suggest sleeping in dark rooms and switching off any artificial sources of blue light.
Artificial Sources of Blue Light
The most common artificial sources of blue light come from TVs, computers, laptops, smartphones and tablets. The use of such devices has become incredibly abundant. It is impacting human lifestyles in an unhealthy manner. Many of us check our phones and laptops late into the night. This confuses the natural function of the brain. When it is readying our bodies for rest, the blue light emission from the device forces it to slow down the production of melatonin. This automatically reduces the quality of sleep.
Eye Exposure to the Blue Light
The excessive use of electronic devices can harm the human eye. Blue light is quite high in intensity along the visible light spectrum. It is just below the UV radiation, which we know can be incredibly harmful. Being so close to UV on the spectrum, many experts believe that blue light can almost have similar harmful effects on the human eye. It may not be as intense as UV itself but the long-term exposure is questionable.
Eye experts advise limiting the use of blue-light emitting devices. 43% of adults work in a job that requires prolonged use of a computer or tablet. An excessive exposure in the long-term could increase the risk of losing central vision, which is also known as macular degeneration. Due to the high flicker rate of blue light wavelengths, they create a glare that deteriorates visual contrast, sharpness, and clarity. This is also the reason why most people commonly feel an eye strain after using these devices for long hours.
In natural occurrence, blue light is everywhere. With poor environmental conditions, our eye’s natural filters are also insufficient to protect against it. So adding more exposure in the form of electronic devices and fluorescent lights is only going to create more harmful effects.