Computer Vision Syndrome (CVS), sometimes termed Digital Eye Strain, describes a group of eye and vision-related problems that result from prolonged exposure to digital screens for computers, televisions, tablets, e-readers and cell phones. Many individuals experience eye discomfort and vision problems when viewing digital screens for extended periods.
Somewhere between 50% and 90% of people who spend more than an hour or two daily in front of a computer screen have at least some symptoms of eye trouble. Computer eye problems are even more likely to occur if you already have an eye problem — like 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 ability to focus on near and far objects starts to diminish after about age 40 – a condition termed presbyopia.
Typical symptoms include eye irritation with dry, itchy or red eyes, blurry or double vision, headache and neck or back pain. While none of these problems has been shown to cause permanent eye damage, they do cause significant discomfort.
There are multiple ways to mitigate or alleviate most of these annoyances. The optimal position for your computer monitor is slightly below eye level, about 20 to 28 inches away from your face. This position means you shouldn’t have to stretch your neck or strain your eyes to see what’s on the screen. Adjust the brightness, contrast, and font size on your screen until you find the ideal settings for your visual comfort. Orient the position of your display to avoid reflections from sunlight or light fixtures. A matte screen surface or added screen filter can reduce glare. Avoid fluorescent lighting as much as possible; subdued or indirect incandescent room lighting is preferable.
At rest, you ordinarily blink from 10 to 30 times a minute; staring at printing on paper or a computer screen slows your blink rate by 60%. This means the tear film protecting your eye surface is refreshed less frequently and your eyes literally become dry. At a minimum, take a break and look away from the screen every 20 minutes; look at something at least 20 feet away for about 20 or more seconds to rest your eyes. Rest your eyes for 15 minutes after two hours of continuous computer use. Lubricant eye drops can be a significant help if used as soon as symptoms begin.
If these measures are not adequate, you may want to discuss computer glasses with your eye doctor. Computer screens located at the recommended 20 to 26 inches from the user’s eyes are in an intermediate zone of vision that is closer than driving (“distance”) vision, but farther away than reading (“near”) vision. Computer glasses customized for this distance provide a clear, wide field of view without excessive focusing effort or unhealthful posturing. Antireflective coating or tinting may also be helpful. If you take this step, don’t forget to measure the distance from the bridge of your nose to the surface of your computer screen before your eye exam!