THE BLUE DANGER
White light is built up out of 7 colors (wavelights) going from red, orange, yellow, green, blue, indigo and violet. The blue wavelight is shorter than the red one. The shorter the wavelight , the more energy and the more focalisation. So you cazn understand the two problems of blue light:
a) problems because of high energy: blue hazard
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The higher the energy, the more damage to eye tissues. Known is that UV light give damage (a kind of burning ) to skin and eyes. Blauw light is closer to UV light than red ligt. Therefore it gives more irritation.
Unluckely blue light is frequent. The more blue light , the clearer the image. More red light is softer and seems more comfortable "warm light". Light with much blue is called "cold light" |
For light in rooms, people choose for warm light. Tv en other screens (computer / smartphone ) use cold light. Because of the higher energy you can understand that a lot of people complain of eye irritation when they work on a computer for the hole day.
Another phenomenon that plays : our eyes must "focus" for near. That asks an effort, surely when you work the whole days on a computer. A near add in your glass can help. We call these glasses "Eyezen glasses"
b) Problems by stronger focalisation : blue haze
Like you see on the following pictures blue light focuses before the retina and gives a haze : the blue haze
THE SOLUTION : FILTER BLUE LIGHT WITH SPECIAL COATING OF THE GLASSES:
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"BlueControl" (Hoya)
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Crizal Prevencia (Essilor)s
A litte filmp explains the problem even better :