HIGH ENERGY VISIBLE LIGHT
What is High-Energy Visible Light ?
Also called blue light, High-Energy Visible Light (“HEV”) covers wavelengths from 380 to 500 nm.
Due to its high energy, HEV is more scattered than the other wavelengths of the visible spectrum, that is why a clear sky appears blue to our eyes. Blue light is also emitted by a great number of artificial light sources as well as by direct sunlight.
Why is High Energy Visible Light dangerous for our eyes?
High-Energy Visible Light is the most energetic part of the visible light spectrum and thus can lead to retinal toxicity, all the more as it is not blocked by physiological filters like tear film, cornea, crystalline lens and vitreous body, except when you have reached a certain age. No significant clinical association has yet been demonstrated between blue light exposure and AMD in human beings. However, the harmfulness of HEV radiations to the retina has been amply documented during last the 30 years. The damage observed is the same as cumulative damage which appears in AMD, suggests that a relationship really exist.
When it comes to sun exposure, better be safe than sorry!
Lenses which filter HEV, especially if they are worn early enough in one’s life, are therefore very likely to be efficient at preventing the premature ageing of the retina.
With life expectancy always on the way up, a growing attraction for warm and sunny areas, the development of outdoor leisure and the depletion of the ozone layer, wearing such lenses must be seriously taken into account, especially as it is risk-free, easy and affordable for everyone.