Can Digital Devices Damage Your Eyes?
The BLUE Light Warning…
Looking at a smart phone screen late at night may affect the user’s ability to sleep afterwards
Blue light sources are becoming increasingly common in today’s environment. Exposure to blue light comes from a variety of technologies including computers, smart phones, televisions, lights.
Light is transmitted to the retina through the lens. In humans, the amount of light transmitted by the lens is age-dependent. In young children, more than 65% of blue light is transmitted. This transmission rate decreases over time; at age 25, only 20% of blue light is transmitted to the retina. The decreased transmission of blue light occurs as our eye’s lens naturally yellows and absorbs more blue light over time, thus preventing blue light from reaching the retina. As a result of this natural process, younger people are more susceptible to the effects of blue light.
Blue light exposure has been shown to impact health. Natural exposure to blue light during the daylight hours boosts people’s energy, alertness and mood. However, elongated exposure to the waves transmitted through screen devices during the evening can disrupt circadian rhythm and cause various health effects including a disruption in normal sleep schedules.
Many indoor light bulbs contain a blue wavelength light, and when we are exposed to blue light, our body inhibits the release of melatonin, causing us to become more awake. Even the use of computer or phone screens at night can inhibit this release, which in turn can make it hard to fall asleep right away. We respond to blue light even if we cannot see the blue, because our eyes are sensitive to the colour blue. With exposure to light both day and night, our melatonin has trouble detecting night time, which results in trouble falling and staying asleep.