Staring at a computer monitor for hours on end has become a part of the modern workday. And inevitably, all of that staring can put a real strain on your eyes.
The name for eye problems caused by computer use is computer vision syndrome (CVS). CVS is not one specific eye problem. Instead, the term encompasses a whole range of eye strain and pain experienced by computer users.
The signs of a black eye include bruising and swelling of the eyelid and soft tissue around the injured eye, sometimes accompanied by broken blood vessels along the white of the eye, called a subconjunctival hemorrhage.
The discoloration starts out deep purple or blue, then may turn green or yellow before disappearing, usually in about a week.
Research shows computer eye problems are common. Somewhere between 50% and 90% of people who work at a computer screen have at least some symptoms of eye trouble.
In addition, working adults aren't the only ones vulnerable to computer vision syndrome. Kids who stare at portable video games or tablets or who use computers throughout the day at school also can experience eye problems related to computer use, especially if the lighting and computer position are less than ideal.
How Can the Computer Screen Affect Vision?
Computer vision syndrome is similar to carpal tunnel syndrome and other repetitive stress injuries at work. It occurs when you're carrying out the same motion over and over again. Just like those other repetitive stress injuries, computer vision syndrome can get worse the longer you continue the activity.
Working at a computer requires that the eyes continuously focus, move back and forth, and align with what you are seeing. You may have to look down at papers and then back up to type, and the eyes have to accommodate to changing images on the screen in order to create a clear picture for the brain to interpret.
All of these functions require a lot of effort from eye muscles. Working on a computer is more challenging to your eyes than reading a book or piece of paper, because a computer screen also adds the elements of screen contrast, flicker, and glare. Computer eye problems are more likely to occur if you already have an eye problem -- such as nearsightedness or astigmatism -- or if you need glasses but don't wear them or wear the wrong prescription for computer use.
Working at a computer gets even more difficult as you get older. That's because the lens of your eye becomes less flexible. The ability to focus on near and far objects starts to diminish after about age 40 -- a condition called presbyopia.