Eye and vision problems are the most frequently reported health care issues among computer users, at work or at home. March is “Save Your Vision” month, and there are several things you can do to have healthy vision at the computer.
Blurred vision and dry eye contribute to computer vision syndrome, which the American Optometric Association defines as "the complex of eye and vision problems related to near work that are experienced during or related to computer use."
Sitting at a computer generally causes a person to look straight ahead for long stretches, work in a dry office or home environment, and to blink less often. Additionally, computer use requires specific vision skills, which add further demands to the visual system and contribute to eye and vision discomfort. These skills include:
Ocular motility — the ability of the eyes to move in various positions.
Accommodation — the ability of the eyes to focus clearly at various distances.
Vergence — The ability to move the eyes in (convergence) or out (divergence).
Computer workspaces can also place demands on the visual system. Each of these factors can play part in eye comfort while computing:
Screen placement -- Place the monitor 20"-26" from your eyes, depending on the size of the monitor and individual vision conditions. The monitor and keyboard should be straight ahead. The top of the monitor should be slightly below horizontal eye level. Tilt the top of the monitor away from you at a 10 degree to 20 degree angle. The center of the monitor should be 10 degrees to 20 degrees below your eyes at a distance of 24". Place document holders close to the screen within the same viewing distance.
Screen resolution — Better resolution offers greater clarity and usually leads to improved comfort. Adjust the resolution to the highest resolution your monitor will support. If the increased screen resolution makes items too small, try increasing the font size (DPI) to compensate. Keep the monitor free of fingerprints and dust. Both can reduce clarity.
Screen contrast — Adjust the contrast between the characters on the monitor and the background so the letters are easily read. Adjust the brightness of the monitor to an intensity that is comfortable to your eyes--not too bright and not too dim. Adjust both brightness and contrast for the best clarity.
Screen glare and reflections — Minimize reflected glare on your monitor by using window treatments, dimmer switches on lights and glare reduction filters. Look for glare reduction filters that have received the American Optometric Association Seal of Acceptance. Proper adjustment should eliminate any reflected images from the monitor screen. To reduce glare, eliminate bright light sources from your peripheral vision and position your monitor perpendicular to windows or other bright light sources.
Working distances and angles — It is important to work at a distance that is comfortable for you and where the image on the screen is clear. Having to move your head to an awkward angle to see the screen clearly suggests that your monitor may need adjustment.
Repetitive and stressful tasks — Difficult tasks are challenging. Don't forget to take occasional breaks and let the eyes look far away while resting, blink forcefully, moisturize the eyes with artificial tears, if necessary, and use a humidifier.
General eyeglass prescription may not be adequate — Computers are usually further and higher than a typical reading task. Glasses for most people wearing bifocals are not adjusted for this new distance or angle and therefore often are not adequate for using the computer. Have a regular comprehensive eye exam to ensure your eyes are healthy and that you have the correct glasses or contact lens prescription. Tell your optometrist about the computer work you do.
Source: American Optometric Association website, www.aoa.org
Cindi Dinger, on behalf of the Wellness Committee