San Diego Health archives...
Computer Eye Strain Symptoms, Causes and Solutions
If you find yourself suffering from frequent headaches, burning or painful eyes, or blurred vision at work, you're not alone.
While physiological problems must always be considered as a possible cause, for an increasing number of us, eye problems can be linked to spending hours working intensely at a computer. (In fact, OSHA in 1999 estimated that 90 percent of the 70 million U.S. workers using computers for more than 3 hours per day experience Computer Vision Syndrome (CVS) in some form.)
Fortunately, (1) the symptoms are usually only temporary. (They usually diminish with time away from the computer - though some doctors feel that heavy computer users may lead to a greater tendency toward developing glaucoma) and (2) the folks at Apple have come up with possible solutions to help minimize the problem entirely. Here are some of their observations and recommendations:
1) EYE STRAIN
SYMPTOMS
- Ocular fatigue (similar to what happens with long stretches of driving an automobile - particularly at night
- Dry, itchy, red, stinging or painful eyes (perhaps even a gritty sensation)
- Headaches
COMMON CAUSES
- Monitor glare
- Outdated eyeglass prescriptions
- Reading too small type size
- Poor screen contrast
- Noticeable screen flicker
POSSIBLE SOLUTIONS
- Close window blinds
- Reposition lighting. If possible, use a desk lamp rather than overhead lighting
- Adjust monitor position and tilt
- Adjust monitor brightness and contrast (free, helpful, online tools are available at http://www.lagom.nl/lcd-test)
- With older, CRT monitors, higher refresh rates (flicker speeds) of at least 75 hertz Hz are preferable Flicker however is not a concern with new flat panel displays which are controlled by "backlight" technology
- Select a screen with the highest resolution possible. Resolution is related to the "dot pitch" of the display. Generally, displays with a lower dot pitch have sharper images. Choose a display with a dot pitch of .28 mm or smaller
2) BLURRED VISION
COMMON CAUSES
- Normal physiological changes like aging, disease, etc.
- Constantly focusing on objects that are 12" or closer
POSSIBLE SOLUTIONS
- Position your monitor a comfortable 18" to 24" away, at or just below eye level. (If using a laptop, open the screen to a comfortable viewing angle.)
- Clean your monitor regularly
- Get glasses that are prescribed specifically for computer use
- Have eyes checked at least once a year
- Take visual breaks (closing eyes or looking away to vary focal distance)
- Move around and take frequent breaks
3) DRY OR IRRITATED EYES
COMMON CAUSES
- Constant, intense focus reduces blinking which is the body's way of keeping eyes moist and refreshed
- Air blowing in the face
POSSIBLE SOLUTIONS
- Close eyes or look away from the computer more frequently
- Eye drops / artificial tear substitute may relieve symptoms
In summary, spending long days at the computer is something that many of us can not avoid. Suffering from the resulting eye strain and discomfort, however, may be largely preventable. Here are a couple final tips to consider:
Remember to blink: Every hour or so, blink 20 times in a row while working at your computer. This will naturally rest and lubricate dry eyes.
Practice the 20-20-20 rule: Look away from your computer at least every 20 minutes and gaze at a distant object (at least 20 feet away) for at least 20 seconds. Looking far away relaxes the focusing muscle inside the eye to reduce fatigue.
References:
http://www.apple.com/about/ergonomics/vision.html
http://www.visionworksusa.com/computereyestrain.htm
http://www.allaboutvision.com/cvs/irritated.htm
http://www.naturaleyecare.com/diseases.asp?d_num=14
