Understanding Blue Light (Blue Light Part 1)



Understanding Blue Light

How are you reading this article?  On your computer? On your phone?  Are you inside? If you answered ‘yes’ to at least one of those questions, chances are, you’re looking at a blue light!

Light-emitting diodes (more often just called LEDs) are everywhere in modern life.  They allow us to have useful devices like computers, tablets, and smartphones.  LEDs have a peak emission in the blue light range.  All around us, there are waves of different kinds of radiation.  The waves we can see are called the visible spectrum and we see it as light.  That light is made up of different colors.  If you’re having trouble visualizing this, think of the Pink Floyd cover of the triangle and the rainbow. That’s a representation of plain light being dispersed by a prism in order to show all the colors that are contained in it. 


  1. Blue Light Part 1
  2. Blue Light Part 2
  3. Blue Light Part 3
  4. Blue Light Recipes
  5. Blue Light Advanced

Different colors are visible because they have different wavelengths.  Red has the longest wavelength and violet has the shortest.  Since blue is close to violet, its wavelength is on the shorter side.  LED lights have a peak emission in the blue light range, which means that the waves it gives off are these shorter “blue” waves, even if we don’t necessarily perceive them as being the color blue.

Why Does Blue Light Affect Us?

As you can see from the refraction, all colors of light are around us at any given moment.  They’re a part of the sun’s natural light and are the reason that sky looks blue (the air acts like the prism and scatters the light so the blue is visible).  However, when we use our LED devices, we’re getting much more exposure to blue light than we would otherwise.  Our eyes developed to view the visible “white” light and filter out UV rays not blue light and since blue light has a shorter wavelength, it is more difficult to focus on creating eye strain.  Artificial light can also upset our natural sleep rhythm which affects how much and when our bodies produce hormones.

However, there is lots of research being done on the benefits of blue light and why we experience them.  Studies acknowledge negatives of blue light and manipulate these effects to try and use blue light to benefit the subject.  For instance, a major drawback of blue light (and green light) is that it disrupts your sleep.  Researchers looked at the bright side of this predicament and figured out they could use blue light to increase alertness and cognitive function during the day.

In Part 2 of this post, I’m going to go into more detail about negative and positive effects of blue light.  In my next post, I’ll let you in on some of the benefits, and in my third post I’ll show you how to minimize the negative and maximize the positive effects of blue light!

TLDR: Bluelight from our indoor environment may be messing with your health.