More than 50 percent of computer users experience eyestrain, headaches, blurred vision and other visual symptoms related to sustained use of the computer. This type of stress on the visual system can also cause body fatigue and reduced efficiency at work. In addition, there are now indications that heavy computer users are at risk for glaucoma.
Many of these symptoms can be reduced through a combination of correcting workstation conditions, posture, stress-relieving lenses prescribed specifically for computer operation, special anti-glare screens, eye exercises and nutritional supplementation.
We were born to have hunters' eyes, needed for spotting game or danger at a distance. But during the last 50 years nearly all our work and much of our recreation, for example, video games, has shifted the focus of our vision to arm's length. This increased amount of near visual tasks often produces such changes as nearsightedness, suppressed vision in one eye, poor eye teaming and reduced efficiency at work and at play.

Many computer users experience visual stress due to: 1) an increase in the number and complexity of necessary eye movements and focusing skills, 2) poor lighting conditions, glare and distracting reflections, 3) screen flicker rate, and 4) above all, the extended amount of computer use.
The following is a Computer Stress Checklist:
Computer visual stress may underlie many direct and indirect symptoms. Eyestrain is a common direct symptom, while the need for shifts in posture and muscular strain resulting from poorly arranged work stations cause eye problems indirectly and other physical problems directly.
Direct Computer Stress Symptoms
headaches while doing or following computer use
irritated and/or dry eyes
blurred vision
slow refocusing when looking from screen to distance objects
frequently losing place when moving eyes between copy and the screen
difficulty seeing clearly at a distance after prolonged computer use
occasional doubling of vision
changes in color perception
changes in glasses prescription

Computer Vision Syndrome describes a group of eye and vision-related problems that result from prolonged computer use. Many individuals experience eye discomfort and vision problems when viewing a computer screen for extended periods. The level of discomfort appears to increase with the amount of computer use.
The most common symptoms associated with Computer Vision Syndrome (CVS) are
eyestrain
headaches
blurred vision
dry eyes
neck and shoulder pain
These symptoms may be caused by:
poor lighting
glare on the computer screen
improper viewing distances
poor seating posture
uncorrected vision problems
a combination of these factors
The extent to which individuals experience visual symptoms often depends on the level of their visual abilities and the amount of time spent looking at the computer screen. Uncorrected vision problems like farsightedness and astigmatism, inadequate eye focusing or eye coordination abilities, and aging changes of the eyes, such as presbyopia, can all contribute to the development of visual symptoms when using a computer.


Your Eye Examination For Computer Use
Due to the unique characteristics and high visual demands of computer work, computer users should have a comprehensive eye examination periodically. Your examination should include:
A general eye and health history
A specific history relating to computer work. Be prepared to describe the type of computer work you do, the number of hours, the time of day you usually work on the computer, the size, type and color of your screen and screen characters, positions and work distances in your workstation, the lighting in the room, and the type severity and frequency of any symptoms you're having.
A measurement of your visual acuity at distance and near
Do an evaluation of your internal and external eye health
A measurement of possible prescriptions for distance and near working distances
An assessment of eye focusing ability
An evaluation of eye coordination and eye movement skills
If the results of your examination indicate your eye doctor may do additional tests based on your specific needs.