[header] How to protect your eyes when using a computer [title] Sit far enough away from the screen. [step] This is usually considered at least an arm's length away from the screen. To make sure your computer is positioned right, try the high-five test: if you can properly high-five your computer screen with a full arm extension, you're sitting too close. 
[title] Locate the computer screen 4 or 5 inches below your eye level. [step] Ideally, you should look down at the computer screen at about a 15 to 20 degree angle.