What causes computer vision syndrome (CVS)?

Computer vision syndrome (CVS) is caused by viewing a computer screen for long periods of time. CVS can cause headaches, blurred vision, neck pain, fatigue, eye strain, dry eyes, double vision, vertigo/dizziness, and difficulty refocusing the eyes.
Unlike words printed on a page that have sharply defined edges, electronic characters (which are made up of pixels) have blurred edges, making it more difficult for eyes to maintain focus. Unconsciously, the eyes repeatedly attempt to rest by shifting their focus to an area behind the screen, and this constant switch between screen and relaxation point creates eyestrain and fatigue.

Even if you wear glasses or contacts, you're susceptible because your prescription might not match up to the specific viewing distances of your screen, thus creating eyestrain. This makes it even tougher to focus and can also cause you to twist and turn and bend your head into all sorts of funny angles to help with focus -- hence the headaches and neck pain that are also a part of computer vision syndrome (CVS).

There are other contributing culprits at work here: Many times, along with reading on these devices come glare, poor seating posture, bad lighting, improper viewing distances and vision problems that are uncorrected to begin with (like farsightedness and astigmatism). And then, like many other health problems, the changes that occur in your eyes with aging factors into it, too.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.