ABL Health: Computer Eye Strain: 10 Steps for Relief

 

With so many of us using computers at work, computer eye strain has become a major job-related complaint. Studies show that eye strain and other bothersome visual symptoms occur in 50 to 90 percent of computer workers.

These problems can range from physical fatigue, decreased productivity and increased numbers of work errors, to minor annoyances like eye twitching and red eyes.

Here are 10 easy steps you can take to reduce your risk of computer eye strain and other common symptoms of computer vision syndrome (CVS):

1. Get a comprehensive eye exam.

Having a routine comprehensive eye exam is the most important thing you can do to prevent or treat computer vision problems.

According to the National Institute of Occupational Safety and Health (NIOSH), computer users should have an eye exam before they start working on a computer and once a year thereafter.

During your exam, be sure to tell your eye doctor how often you use a computer at work and at home. Measure how far your eyes are from your screen when you sit at your computer, and bring this measurement to your exam so your eye doctor can test your eyes at that specific working distance.

2. Use proper lighting.

Eye strain often is caused by excessively bright light either from outdoor sunlight coming in through a window or from harsh interior lighting. When you use a computer, your ambient lighting should be about half as bright as that typically found in most offices.

Eliminate exterior light by closing drapes, shades or blinds. Reduce interior lighting by using fewer light bulbs or fluorescent tubes, or use lower intensity bulbs and tubes. If possible, position your computer monitor or screen so windows are to the side, instead of in front or behind it. (more after the cut)

Many computer users find their eyes feel better if they can avoid working under overhead fluorescent lights. If possible, turn off the overhead fluorescent lights in your office and use floor lamps that provide indirect incandescent or halogen lighting instead.

Sometimes switching to "full spectrum" fluorescent lighting that more closely approximates the light spectrum emitted by sunlight can be more comforting for computer work than regular fluorescent tubes. But even full spectrum lighting can cause discomfort if it's too bright. Try reducing the number of fluorescent tubes installed above your computer workspace if you are bothered by overhead lighting.

3. Minimize glare.

Glare on walls and finished surfaces, as well as reflections on your computer screen also can cause computer eye strain. Consider installing an anti-glare screen on your monitor and, if possible, paint bright white walls a darker color with a matte finish.

Again, cover the windows. When outside light cannot be reduced, consider using a computer hood.

If you wear glasses, purchase lenses with anti-reflective (AR) coating. AR coating reduces glare by minimizing the amount of light reflecting off the front and back surfaces of your eyeglass lenses.

If your older monitor is causing computer eye strain, replace it with a flat-panel LCD screen that is easier on the eyes.

4. Upgrade your display.

If you have not already done so, replace your old tube-style monitor (called a cathode ray tube or CRT) with a flat-panel liquid crystal display (LCD), like those on laptop computers.

LCD screens are easier on the eyes and usually have an anti-reflective surface. Old-fashioned CRT screens can cause a noticeable "flicker" of images, which is a major cause of computer eye strain. Even if this flicker is imperceptible, it still can contribute to eye strain and fatigue during computer work.

Complications due to flicker are even more likely if the refresh rate of the monitor is less than 75 hertz (Hz). If you must use a CRT at work, adjust the display settings to the highest possible refresh rate.

When choosing a new flat panel display, 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.

Flicker is not an issue with LCD screens, since the brightness of pixels on the display are controlled by a "backlight" that typically operates at 200 Hz.

If you see a lower refresh rate (e.g. 60 Hz) noted on an LCD screen, don't worry — this refers to how often a new image is received from the video card, not how often the pixel brightness of the display is updated, and this function typically is not associated with eye strain.

Finally, choose a relatively large display. For a desktop computer, select a display that has a diagonal screen size of at least 19 inches.

Computers and Contacts

Do Contact Lens Wearers Have More Computer Vision Problems?

June 2014 — Because so many computer users wear contact lenses, researchers in Spain recently reviewed published studies to see if contact lens wear increases the risk of computer vision problems or causes a worsening of computer vision syndrome.

The investigators found 114 studies written in English or Spanish and published from 2003 to 2013 that referenced both contact lenses and computer use. They chose six studies for final analysis.

All six revealed that contact lens wearers were more likely to have computer vision syndrome symptoms than individuals who wore eyeglasses only or did not need corrective lenses. Prevalence of symptoms ranged from 17 to 95 percent among contact lens wearers and 10 to 58 percent among non-wearers. Also, contact lens wearers were four times more likely to have dry eyes during or after computer use, compared with non-wearers.

Silicone hydrogel contact lenses were associated with more comfort than regular soft lenses among computer users.

The study authors concluded that, during computer use, contact lens wearers suffer more eye discomfort and visual disturbances than non-wearers. But they also stated that, due to the small number of studies included in their analysis and the non-conclusive nature of some findings, more research is needed to determine the best type of contact lenses for computer users and how the lenses should be used.

A report of the study was published in the March/April 2014 issue of the journal Revista Espanola de Salud Publica.

5. Adjust your computer display settings.

Adjusting the display settings of your computer can help reduce eye strain and fatigue. Generally, these adjustments are beneficial:

• Brightness. Adjust the brightness of the display so it's approximately the same as the brightness of your surrounding workstation. As a test, look at the white background of this Web page. If it looks like a light source, it's too bright. If it seems dull and gray, it may be too dark.
• Text size and contrast. Adjust the text size and contrast for comfort, especially when reading or composing long documents. Usually, black print on a white background is the best combination for comfort.
• Color temperature. This is a technical term used to describe the spectrum of visible light emitted by a color display. Blue light is short-wavelength visible light that is associated with more eye strain than longer wavelength hues, such as orange and red. Reducing the color temperature of your display lowers the amount of blue light emitted by a color display for better long-term viewing comfort.

For computers running on a Microsoft Windows operating system, display settings can be adjusted in Control Panel. For an Apple computer, display settings are found in Systems Preferences (in the Applications folder in Finder).

In some cases, the color temperature of a desktop computer monitor is adjusted on the display itself.

Eye Comfort Tips

Text Size and Color on Your Digital Screen

To avoid eye strain, at what size should your computer display text? According to computer vision syndrome expert Dr. James Sheedy, it should be three times the smallest size that you can read from your normal viewing position.

The best color combination for your eyes is black text on a white background, though other dark-on-light combinations also work well.

If you use Windows 7, you can adjust text size and color by going to the Start menu, opening the Control Panel and choosing Display. Here you can also adjust your screen's resolution and brightness, for best visual comfort.

You can adjust text size when using Internet Explorer, Firefox, Safari and other browsers, too. For example, in Firefox, you can enlarge an entire webpage by using the keyboard command Ctrl + as many times as you want, while Ctrl 0 makes everything normal-sized again. (Ctrl - makes everything smaller.) To enlarge only the text, use Alt V, then Z, then T. Then use Ctrl + again, and you'll see just the text enlarging.

Each browser and email program has different commands for adjusting text size, so look through the menus to learn what they are. Or visit Google and search for how-tos there.

Many smart phones let you adjust text size. For example, on the iPhone 4, you simply open the Settings menu, then choose General, then Accessibility, then Large Text. Here you can choose a new font size for core applications such as Mail, Notes and Calendar. The font will also display in certain third-party applications.

Whatever type of digital screen you're using, you'll enjoy it more if you make the effort to adjust the view for your visual comfort. Don't know how? Check the manufacturer's website or look it up on Google. — L.S.

6. Blink more often.

Blinking is very important when working at a computer; blinking moistens your eyes to prevent dryness and irritation.

When working at a computer, people blink less frequently — about one-third as often as they normally do — and many blinks performed during computer work are only partial lid closures, according to studies.

Tears coating the eye evaporate more rapidly during long non-blinking phases and this can cause dry eyes. Also, the air in many office environments is dry, which can increase how quickly your tears evaporate, placing you at greater risk for dry eye problems.

If you experience dry eye symptoms, ask your eye doctor about artificial tears for use during the day.

By the way, don't confuse lubricating eye drops with the drops formulated to "get the red out." The latter can indeed make your eyes look better — they contain ingredients that reduce the size of blood vessels on the surface of your eyes to "whiten" them. But they are not necessarily formulated to reduce dryness and irritation.

To reduce your risk of dry eyes during computer use, try this exercise: Every 20 minutes, blink 10 times by closing your eyes as if falling asleep (very slowly). This will help rewet your eyes.

To ease eye strain, make sure you use good lighting and sit at a proper distance from the computer screen.

7. Exercise your eyes.

Another cause of computer eye strain is focusing fatigue. To reduce your risk of tiring your eyes by constantly focusing on your screen, 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. Some eye doctors call this the "20-20-20 rule." Looking far away relaxes the focusing muscle inside the eye to reduce fatigue.

Another exercise is to look far away at an object for 10-15 seconds, then gaze at something up close for 10-15 seconds. Then look back at the distant object. Do this 10 times.

This exercise reduces the risk of your eyes' focusing ability to "lock up" (a condition called accommodative spasm) after prolonged computer work.

Both of these exercises will reduce your risk of computer eye strain. Also, remember to blink frequently during the exercises to reduce your risk of computer-related dry eye.

8. Take frequent breaks.

To reduce your risk for computer vision syndrome and neck, back and shoulder pain, take frequent breaks during your computer work day.

Computer Vision News

New Report on Digital Eye Strain

January 2016 — "Eye Overexposed: The Digital Device Dilemma" is The Vision Council's latest report on digital eye strain.

With our constant exposure to digital devices, the document reveals that not only young adults, but children and older folks, too, are experiencing symptoms like eye strain, headaches, dry eyes, blurred vision and pain in the neck, shoulder and back.

The report is full of new statistics that may surprise you. For example, more than 30 percent of Americans 60 and older have used digital devices for two or more hours per day for more than 15 years. And nearly nine of 10 young adults use two or more devices at a time.

Those numbers are based on findings from a late 2015 survey conducted by The Vision Council among 10,329 U.S. adults. The study updates previous yearly reports released by the organization. Download the report here. — L.S.

Many workers take only two 15-minute breaks from their computer throughout their work day. According to a recent NIOSH study, discomfort and eye strain were significantly reduced when computer workers took four additional five-minute "mini-breaks" throughout their work day.

And these supplementary breaks did not reduce the workers' productivity. Data entry speed was significantly faster as a result of the extra breaks, so work output was maintained even though the workers had 20 extra minutes of break time each day.

During your computer breaks, stand up, move about and stretch your arms, legs, back, neck and shoulders to reduce tension and muscle fatigue.

Check your local bookstore or consult your fitness club for suggestions on developing a quick sequence of exercises you can perform during your breaks and after work to reduce tension in your arms, neck, shoulders and back.

9. Modify your workstation.

If you need to look back and forth between a printed page and your computer screen, this can cause eye strain. Place written pages on a copy stand adjacent to the monitor.

Light the copy stand properly. You may want to use a desk lamp, but make sure it doesn't shine into your eyes or onto your computer screen.

Improper posture during computer work also contributes to computer vision syndrome. Adjust your workstation and chair to the correct height.

Purchase ergonomic furniture to enable you to position your computer screen 20 to 24 inches from your eyes. The center of your screen should be about 10 to 15 degrees below your eyes for comfortable positioning of your head and neck.

10. Consider computer eyewear.

For the greatest comfort at your computer, you might benefit from having your eye care professional modify your eyeglasses prescription to create customized computer glasses. This is especially true if you normally wear contact lenses, which may become dry and uncomfortable during sustained computer work.

Computer glasses also are a good choice if you wear bifocals or progressive lenses, because these lenses generally are not optimal for the distance to your computer screen.