I include myself in saying that we go through hours at a time staring at a screen. That magic box in front of you that takes you right in into a different world. Do you even blink? There is a rule called "The 20 - 20 -20 rule". This rule gives us some basic numbers so we can avoid dry eyes, red eyes, purple eyes, and just any color of eyes. The point is, we need to rest our vision. Just follow these numbers: Every 20 minutes take a 20 second break to look at objects 20 feet away. That;s it. Try it to rest your vision hard at work.