Computer vision syndrome is the leading occupational health problem of the twenty-first century. It’s symptoms affect nearly 70 percent of all computer users.
Computer vision syndrome, also referred to as digital eye strain, describes a group of eye and vision- related problems that results from prolonged use of computer, tablet and cell phone for an extended time.
Globally, computer is one of the common office tools used in various institutions.
Symptoms of computer vision syndrome(CVS) which are referred to as digital eye strain include:
- Dry and irritated eyes
- Eye strain/fatigue
- Blurred vision
- Red eyes
- Burning eyes
- Excessive tearing
- Double vision
- Light/glare sensitivity
- Slowness in changing focus
These symptoms may be caused by:
- Poor lighting
- Glare on a digital screen
- Improper viewing distance
- Poor seating posture
- Uncorrected vision problems
The extent of visual symptoms which individuals experience often depends on the level of their visual abilities and the amount of time spent looking at a digital screen. Visual problems like farsightedness, astigmatism, presbyopia( an age related changes of the eyes), all contribute to the development of visual symptoms to the computer users.
Many of the visual symptoms experienced by the users are temporary and will reduce after discontinuing computer work or use of the digital device. However, some individuals may experience continuous reduction in visual abilities such as blurred distance vision, even after stopping work at a computer.If nothing is done to address the cause of the problem, the symptoms will continue to recur and perhaps worsen with future digital screen use.
Some important factors in preventing or reducing the symptoms of Computer Vision Syndrome(CVS) includes lighting conditions, chair comfort, location of reference materials, the position of the monitor and the use of rest breaks.
- Location of the computer screen
Most people find it more comfortable to view a computer when the eyes are looking downward. Optimally, the computer screen should be 15 to 20 degrees below eye level(about 4-5 inches) as measured from the centre of the screen and 20 to 28 inches away from the eyes.
Position the computer screen to avoid glare, particularly from overhead lighting or windows. Use blinds or drapes on windows and replace the light bulbs in desk lamps with bulbs of lower wattage.
If there is no way to minimize glare from light sources, consider using a screen glare filter. These filters decrease the amount of light reflected from the screen.
- Seating position
Chairs should be comfortably padded and confirm to the body. Chair height should be adjusted so the feet rest flat on the floor. Arms should be adjusted to provide support while typing and wrists should not rest on the keyboard when typing.
- Reference materials:
These materials should be located above the keyboard and below the monitor. Instead, a document holder can be used beside the monitor, if this is not possible. So the head does not need to be repositioned from the document to the screen
- Rest breaks:
To prevent eyestrain, try to rest eyes when using the computer for long periods. Follow 20-20-20 rules, which means, for every 20 minutes of computer viewing, look at a distance of 20 metre for at least 20 seconds which allow eyes a chance to refocus.
Try to blink frequently when using computer for a long time. This helps in keeping the front surface of the eye moist and reduces the chances of developing dry eyes.