CRT Monitors & Eye Strain

CRT monitors are much worse for eyestrain than LCDs.

At least 50 percent of people who use a computer experience eyestrain, claims Dr. Marc Grossman of Visionworks USA. CRT monitors put people at a heightened risk for eyestrain, and even though eyestrain usually does not cause any long-term problems, it can lead to fatigue and poor work performance. If you must use a CRT monitor, you can at least reduce the effects and the chances of eyestrain.

Screen Flicker

The technology used in a CRT monitors causes the screen to flicker no matter what setting, according to PC Review UK. But increasing the refresh rate on a CRT reduces eyestrain. If you want to reduce the effects of flicker, set your CRT to refresh at at least 72 hertz--but higher rates are better and 85 hertz provides an optimal screen to reduce flicker.

Distance

Your CRT can also give you eyestrain due to its location in your workspace, according to the Occupation Safety and Health Administration. You should have between 20 and 40 inches between you and your monitor. However, CRTs are very deep and may not offer the ability to keep a proper distance between your eyes and the monitor.

Symptoms

Eyestrain caused by CRT monitor use has several symptoms other than just tired eyes. You may also have dry and/or irritated eyes, blurry vision and headaches while using the computer and even after looking at the monitor. In addition, you may have trouble focusing on objects after you stop looking at your screen and you may need a new prescription for your glasses.

Prevention

Adjust the position of your monitor so you do not need to squint or lean forward to see small text, but not so close that you cannot focus on text quickly, recommends OSHA. Try to orientate your chair so that you look down at your CRT monitor at an angle of 15 or 20 degrees. Also, if you are a heavy computer user, get frequent eye examinations.

Solution

You should highly consider purchasing an LCD monitor to improve your visual performance, according to Alan Hedge of Cornell University. LCD screens do not flicker at all and allow you a wider variety of postures because they are much thinner than a CRT. In addition, they tend to have far fewer problems with screen glare.

References

• Visionworks USA: Computer Eye Strain: How to Relieve It
• Mayo Clinic: Eyestrain
• PC Review UK: LCD vs CRT
• Occupation Safety and Health Administration: Monitors
• Cornell University: Ergonomics Considerations of LCD versus CRT Displays