Blue light is at the far end of the visible light spectrum (380-460nm), close to ultra violet (UV) light. It is beneficial during the day, since it boosts attention, reaction times and mood.1 However, a portion of blue light in the range of 415-455 nm is believed to be toxic to retinal cells, and is termed as Harmful Blue Light.2
A multitude of sources emit Harmful Blue Light. Indoors, digital devices like smartphones, plasma TVs and fluorescent light bulbs all emit Harmful Blue Light. The sun is the largest source of Harmful Blue Light, emitting at least 100 times more than artificial sources.2
Emerging research indicates a possible link between exposure to Harmful Blue Light and long-term vision issues like age-related macular degeneration (AMD).3
Indoors, Transitions lenses help protect eyes against Harmful Blue Light emitted by artificial sources such as digital devices and LED lights. Outdoors, Transitions lenses provide extra protection by shielding eyes from intense Harmful Blue Light emitted by the Sun, glare and UV rays.
1. Harvard Health Publications (http://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side)
2. Arnault E.,Barrau C., Nanteau C, Gondouin P., Bigot K., Vienot F., Gutman E., Fontaine V., Villette T., Cohen-Tannoudji D., Sahel J., Picaud S., Phototoxic Action Spectrum on a Retinal Pigment Epithelium Model of Age Related Macular Degeneration Exposed to Sunlight Normalized Conditions, PlosOne 8 (2013), DOI: 10.1371/journal.pone.0071398
3. Dillon, James et al., Transmission of light to the aging human retina: possible implications for age related macular degeneration, Experimental Eye Research Volume 79, Issue 6, December 2004, Pages 753-75. DOI:10.1016/j.exer.2004.06.025