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Computer and your eyes

With the increasing use of computers, computer related-vision problems are affecting a growing number of individuals. Visual symptoms include: eyestrain, blurred or double vision, headaches, red or irritated eyes, and color perception changes. Improper workstation set-up, a fragile eye teaming or eye focusing system, or poor visual hygiene can aggravate these symptoms. Individuals who suffer from computer vision syndrome may find relief through specially designed prescription lenses, filters, vision therapy, or adjustments to the workstation. If you experience pain, or visual discomfort when using a computer, you may be suffering from a computer related-vision problem.

The incidence of eye complaints is likely to increase substantially due to the widespread use of computers, according to the Association of Optometrists Ireland. Despite the fact that there is currently no scientific evidence to prove that computer use causes any damage to eyes, the AOI has stated that nonetheless, a large number of computer users experience some form of eye complaint at one time or another. According to the Irish Examiner, AOI President, Mary Eustace, said, "it's a difficult area because there is no technical, clinical term for problems created by extended periods of staring at computers". She added that a few simple steps can reduce strain on the eyes when working with computers.

They include:

Taking frequent breaks from viewing the computer screen.

Having your eyes tested every two years.

Avoiding the use of contact lenses when working with a computer, as they cause the eyes to dehydrate.

The AOI have also expressed concern that schoolchildren will suffer increased eye problems because of the increasing amount of time they are spending on computers, both at school and in the home. Odds are, if you use a computer regularly, you suffer from Computer Vision Syndrome (CVS).  CVS simply refers to a collection of eye and vision problems associated with computer use, and about three-quarters of computer users have it. However, you should take certain steps to alleviate your symptoms so they don't get worse.

Computer Vision Symptoms

The most common symptoms of CVS include: eyestrain or eye fatigue, dry eyes, burning eyes, light sensitivity, blurred vision, headaches and pain in the shoulders, neck or back.

Causes and Treatment

CVS can have multiple causes. Computer vision syndrome causes eye fatigue, which can make you feel tired in general. Problems with your eyes (eyestrain, dry eyes, burning and light sensitivity) during computer use can result from: insufficient tear flow to the eyes, too much glare and reflection on the monitor, monitor settings that are hard on the eyes and needing glasses (for the first time, or a new pair).


First, treat the problem that affects virtually every computer user.

Second, see if glare and reflection are affecting you.

Third, make a few small adjustments to your monitor for fast CVS relief.

Needing new glasses for the computer is more common than most people realize, or are willing to admit. Getting computer glasses can often solve your problems with headaches, and neck, shoulder and back pains as well. Why? Many people, particularly those trying to use the bottom portion of their bifocals for computer work, tip their heads into uncomfortable positions in order to see. However, sometimes your aches and pains are the result of a poor ergonomic set-up; these quick ergonomic tips can help you rearrange your work area so that it is most comfortable for you. Many people are suspicious of their monitors, in particular the amount of radiation they emit (actually a very safe amount: see the sidebar), but the real culprits are eye-unfriendly problems that are easy to correct.

Take a look at your monitor right now. Is it a reasonable distance from your eyes? It should be about 20 to 26 inches away. Is the screen covered in dust? Is your document holder near it? For heaven's sake, clean your monitor every now and then! How do you expect to see through all that dust? And, make sure you place your document holder as close to the screen as possible: constantly looking back and forth between them can tire out your eyes.

Worried about radiation levels of computer monitors? In fact, they are much lower than the maximum allowed.

Brightness and Contrast

Most monitors allow you to adjust the brightness and contrast so that they're easy on your eyes. Make sure to adjust the room's brightness first (see Glare and Reflection), as the room's brightness can affect how you see your monitor; for example, in a too-bright room, your monitor also needs a too-bright setting in order for you to be able to read it.,You should also adjust the contrast to the highest amount you are comfortable with (this should be a very high level of contrast).

Text Size and Color
Adjusting how your monitor displays text can provide welcome eyestrain relief. Ideally, your text size should be three times the smallest text size you can read from your normal viewing position, according to CVS expert Dr. James Sheedy. Relieve eyestrain by adjusting the way your computer displays text. He also recommends black text on a white background as the best color combination for your eyes; other high-contrast, dark-on-light combinations are also acceptable.

Monitor Display Quality
How well your monitor displays everything on the screen depends on three things: refresh rate, resolution and dot pitch.

Refresh rate refers to how often your monitor redraws the screen. Slow rates can be hard on your eyes, and very slow rates cause a noticeable flicker. Ideally, your refresh rate should be 70 Hz (hertz) or higher.

Resolution, which is linked with the refresh rate, refers to a monitor's pixel density: the more pixels, the higher the level of detail. For example, an 800 by 600 resolution will show more detail than a 640 by 480. Generally, the higher the resolution the better, but watch out for that refresh rate: sometimes, the very high resolutions have an inadequate refresh rate, so you need to choose a setting where both are high numbers.

Dot pitch affects the sharpness of the display; the lower the number, the sharper the image. Most monitors have a dot pitch between 0.25 mm (millimeters) and 0.28 mm; 0.28 or lower is desirable. Some monitors are built differently, and therefore list pitch as horizontal dot pitch or stripe pitch. These numbers are always lower than regular dot pitch; to compare, divide your number by 0.866 to get your monitor's equivalent of a regular dot pitch.

You can find information about refresh rate, resolution and dot pitch in your monitor's manual.

Eyes Still Irritated?

Sometimes, the problem is that you need glasses for the intermediate zone of your vision (as opposed to near or far) and don't realize it. You don't ordinarily use that zone very much, but that's where the monitor falls.