Statistics from the National Institute of Occupational Safety and Health suggest that as many as 90% of computer users may suffer from Computer Vision Syndrome (CVS). Symptoms of CVS include headache, blurred vision, fatigue, neck pain, eyestrain, burning, tearing, and trouble refocusing after prolonged periods of uninterrupted viewing.
What Causes CVS:
Viewing close objects such as books or computer screens requires the eyes to constantly work in order to maintain focus, a process called accommodation.
With extended viewing, the strain of accommodation causes fatigue and many of the other symptoms of CVS. With age, everyone slowly loses the ability to change focus or accommodate, such that by the age of 40 most people need help in the form of reading glasses or bifocals to see near objects clearly.
In addition, prolonged, concentrated reading and computer work causes a decreased blink rate, leading to drying of the surface of the eyes. This also contributes to the eye fatigue, burning, tearing and dry eye symptoms that go along with CVS.
Computer Glasses For CVS:
Most people place their computer screens at a working distance of 2-3 feet. This distance requires a moderate amount of focusing effort. If you wear contact lenses or do not require prescription glasses, you may benefit from low-powered reading or computer glasses, which help relieve eyestrain by reducing the effort required to maintain focus at that distance.
What if I Wear Prescription Glasses?
Ready-made computer glasses will not work if you wear prescription glasses since your individual prescription is not incorporated into these glasses. Custom prescription computer glasses can be made, but these are expensive since you will need to purchase another separate pair of glasses. You could try wearing computer glasses over your prescription glasses…but that’s just weird.
Why Bifocals Aren’t the Answer
If you use bifocals, trifocals or progressive add lenses, you are already familiar with the limitations these offer. In order to find the part of the lens that allows you to see the screen clearly you need to adopt uncomfortable head and neck positions. Even then, it is sometimes difficult to use the small bifocal part of the lens for long periods of time. Very annoying.