Visible light waves are the only electromagnetic waves visible to the human eye. They are measured in nanometers. Blue light generally is defined as visible light ranging from 380 to 500 nm. One-third of all visible light is considered high-energy visible (HEV) or "blue" light.
We view these waves as colors, each one having a different wavelength and energy. Red has the longest wavelength and lowest energy while violet, at the opposite end of the spectrum, has the shortest wavelength and highest energy. When all the waves are seen together they create white light. Blue light exists on the farthest end of the visible light spectrum, it’s short wavelength creates a very high energy.
The sun is an example of white light and a natural source of blue light. Exposure during the day can be beneficial. Absorbing natural blue light during the day keeps us awake and alert because of our natural biorhythms. The circadian rhythm (internal clock) follows the sun’s schedule. We rise with the sun and settle as it sets. However, the excessive use of digital devices at night is disrupting this natural routine and affecting young children.
Blue light exists in everything including digital screens, Tv’s and light bulbs.Now that the world has become largely reliant on smartphones and other devices that produce substantial amounts of blue light, the long-term effects are proving to be severely harmful. Blue light reaches far deeper into the eye than other kinds of light. These wavelengths can boost attention and mood during the day but, are extremely disruptive at night. Prolonged excess in digital screen use is affecting the physical and emotional well-being of adults and particularly children ages 6-12.
Ocular Lens Pigment (OLP) is a barrier that begins to form in the lens of the eye in adolescents. We are born without it, so young children have little natural defense to blue light.
Exposure to blue light at night from digital devices makes our bodies think its day time causing a delayed release of the sleep-inducing hormone, melatonin. Studies show children viewing digital screens (computer, phone, tablet, tv, video game) before bedtime are having trouble falling and staying asleep. They are tired and less focused during the day which impairs their learning faculties.