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VDT (Video Display Terminal)/Computer Examination

It is estimated that over 100 million working Americans suffer from computer eyestrain. Nearly 54 million children connect to the Internet each day either at home or in school. If you or your child spend more than two hours each day in front of a computer screen, you likely experience some symptoms of Computer Vision Syndrome or CVS:

  • Headaches
  • Loss of focus
  • Burning/tired eyes
  • Double vision
  • Blurred vision
  • Neck and shoulder pains

The best solution is to see an eye doctor and get a pair of eyeglasses specifically designed to wear when you use the computer. CVS is caused by our eyes and brain reacting differently to characters on the screen than they do to printed characters. Until now, traditional eye exams for near vision have resulted in eyewear suited for reading printed material, not for viewing computer screens.

Our eyes respond well to most printed material, which is characterized by its dense black characters with well-defined edges which contrast markedly from their light background. Healthy eyes can easily maintain focus on the printed page. Characters on a computer screen, however, don’t have this contrast, or well-defined edges. These characters are brightest at their centers and diminish in intensity toward their edges. Our eyes are unable to maintain focus and remain on plane with these images. They instead drift out to a point called the resting point of accommodation (RPA). Our eyes constantly move to the RPA, and then strain to regain focus on the screen. This continuous flexing of the eyes’ focusing muscles creates fatigue and the burning, tired-eyes feeling.

9 Ways to Reduce Computer Vision Syndrome:

1. Get an Eye Exam

This 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 per year thereafter.

2. Use Proper Lighting

In your office you are likely to find several things that can cause eyestrain, including glare on walls and finished surfaces, reflections on the computer screen itself, excessively bright light coming in from outside, and excessively bright light inside. Eliminate exterior light and reflections by closing drapes or blinds. When using computers, lighting should be about half that used in most offices. Reduce lighting by using fewer light bulbs or fluorescent tubes, or use lower intensity bulbs and tubes.

3. Take Frequent Breaks

Full-time computer users should take a 10-minute break every hour to reduce eyestrain problems according to experts. Part-time users should take frequent breaks, after sitting in front of their display for more than a hour.

4. Refocus Your Eyes

Look away from your computer screen every 10-15 minutes and focus for 5-10 seconds on a distant object outside or down the hallway. This prevents the fixed gaze common among computer users. It also encourages you to blink, which lubricates your eyes.

5. Blink More Often

When staring at a computer, people blink less frequently—about 5 times less than normal, according to studies. Tears coating the eye evaporate more rapidly during long non-blinking phases and cause dry eyes. Office buildings may have excessively dry environments that also reduce tearing. For significant problems, ask your eye doctor about artificial tears or eye drops that you can use during the day.

6. Modify Your Workstation

If you need to look back and forth between the printed or written page and the computer, this can cause eyestrain. Place written pages on a copy stand adjacent to the monitor. Properly light the copy stand. Adjust your workstation and chair to the correct height. Purchase ergonomic furniture to ensure proper screen locations and posture.

7. Match the Computer Screen to the Brightness of the Environment

Closely match the brightness of the environment with that of the computer screen. The contrast between the background and on-screen characters should be high.

8. Minimize Glare

Use window shades, blinds or drapes to block out excessive sunlight, or install an anti-glare screen, to minimize reflections on the screen itself. Reduce the internal ambient light if necessary. For conditions where outside light cannot be reduced, use a computer hood to cut glare and reflection. Have an Anti-Reflective coating applied to your glasses. This will prevent glare and reflections on the back side of your lenses form reaching your eyes.

9. Exercise Even When Sitting

Anyone in a sedentary job, especially those using computers, should also stand up, move about, or exercise frequently. NIOSH recommends several sitting, stretching, and joint rotating exercises for computer users.