Definition of Blue Light
Blue light is part of the visible light spectrum that is detectable by the human eye. It has a short wavelength, which means it carries high energy.
Natural and Artificial Sources
Blue light occurs naturally in daylight, but it is also produced by artificial sources such as LED lights, computer screens, smartphones, and other digital devices.
The Visible Light Spectrum
The visible light spectrum ranges from red to violet light. Blue light falls in the short-wave range, between approximately 380 nm and 500 nm.
Wavelengths and Energy
Blue light has wavelengths between 380 and 500 nanometers (nm). Due to its short wavelength, it has higher energy compared to other colours in the visible spectrum.
What Effects Does Blue Light Have on the Eyes?
- Eye Strain: Prolonged exposure to blue light can cause eye strain and discomfort.
- Blue Light Filters and Protective Glasses: Using blue light filters and protective glasses can help reduce eye strain.
- Iris and Retina: Blue light can affect the iris and retina, potentially leading to long-term eye issues.
- Macular Degeneration: Excessive exposure to blue light may contribute to the development of age-related macular degeneration.
How Does Blue Light Affect Sleep?
- Circadian Rhythm: Blue light impacts the circadian rhythm and can disrupt the body's natural sleep cycle.
- Melatonin Production: Evening exposure to blue light can suppress the production of melatonin, a hormone that regulates sleep.
- Screen Time Before Bed: Using screens just before bedtime can make it harder to fall asleep and reduce sleep quality.
- Tips for Reducing Exposure: Limit screen time in the evening, use glasses with blue light filters, and maintain regular sleep routines to minimise exposure.
Read more about how blue light affects sleep in our dedicated guide.
What Are the Benefits of Blue Light?
- Alertness and Focus: Blue light can boost alertness and improve focus when exposed to it in the morning.
- Mood and Cognitive Function: Exposure to blue light can enhance mood and cognitive performance.
- Daylight and Well-Being: Natural daylight, which contains blue light, is essential for well-being and helps regulate the body's biological clock.
Which Devices Emit High Levels of Blue Light?
Many digital devices emit significant amounts of blue light, including:
- Smartphones
- Tablets
- Computer Screens
- LED Lights
- Televisions
How Can You Protect Your Eyes from Blue Light?
- Blue Light Glasses: Wearing glasses that filter blue light can help protect your eyes. Blue Blockers Optic Pro are the best blue-blocking glasses we've tested. They block 99.43% of all blue light.
- Device Settings: Adjust the settings on your digital devices to reduce the amount of blue light they emit, such as by enabling night mode.
How Can You Prevent Health Risks from Blue Light?
- Prolonged Exposure: Limit the time spent in front of screens and take regular breaks.
- Eye Health and Ergonomics: Use proper lighting and maintain good ergonomics to reduce eye strain.
- Preventive Strategies: Use blue light-blocking glasses, blue light filters, adjust screen brightness, and take regular breaks to prevent health problems related to blue light.
