Avoid using LED lights and screens/monitors for visual training
Chinese article: https://lowvisionandcvi.blogspot.com/2018/02/ledipadled_38.html
For trainers, teachers, and parents doing visual training for CVI children or clients, please read about the following explanation on near ultraviolet 'blue light' emitted from LED lights. LED lights are widely used in torches, Christmas decoration lights, festival lights, bicycle lights, not to say lamps, ipads, computer screens, smartphone screens... The near UV blue light emitted from LED lights are doing harm to human eyes especially at close distance and for long duration. So please use them with great caution for your own eyes and your students' or children's eyes.
What is LED ? Its disadvantages, problems, and effects on
human beings
LED is the most recommended light source nowadays. Apart from light bulbs, it is also
used in the background light of electronic display screens, such as your
smartphone1 and computer monitors/screens1, etc.
As LED is not too hot and energy saving, it is greatly promoted and is used to
replace other more traditional light sources, such as fluorescent tubes,
curlicue compact fluorescent light bulbs, and incandescent light bulbs.
However, it is exactly because LED lights produce a fair
amount of light in the blue spectrum4 (or called ‘blue light’), that they are so bright!
There is no free lunch in this world; we may be paying a
price4 to use LED.
According to a research paper called ‘The Effects of Blue
Light On Ocular Health’ 5, written by Elaine Kitchel of the American Printing House
for the Blind, the wavelength of blue light is ‘near UV’ 5:
On the other hand, according to another article ‘Blue light
has a dark side’ by Harvard Health Publications of the Harvard University, “Those
curlicue compact fluorescent light bulbs and LED lights are much more
energy-efficient than the old-fashioned incandescent light bulbs we grew up
with. But they also tend to produce more blue light” 4, please refer to: http://www.health.harvard.edu/staying-healthy/blue-light-has-a-dark-side
Concluding from different researches or articles (which are
listed in the reference list at the bottom of this blog), “short wavelength LED
street lighting ……legitimately raises the question of whether these new light
sources are introducing as many problems as those they are claiming to solve” 3, such as blue hazard6, light pollution2,6, night vision2 in aging eye3, increase glare2,3, poses threat to driving safety at night3 (because of the strong spike of light), “disruption of
nature’s light cycles on all flora and fauna”2, “may contain other hazardous metals such as lead and
arsenic” 6, blue light even
affects our sleep4, causes damage to the retina in eyes1, etc.
So do have a look at the following article 6 and understand what is LED, which you will surely see or
use everyday at close distance, and understand its disadvantages, problems, and
effects:
References：
2. Jim Benya editor: Blue light blues.
3. Deborah Burnett (2009): Driving at night – how light
affects the eyes of aging drivers.
