Computer Users Guide

Studies show that as many as 50-90% of computer users experience the symptoms of Computer Vision Syndrome (CVS). Viewing a computer screen is different than viewing a printed page. Letters on the computer screen are not as sharply defined and the contrast between the text and the background is poor. Also things like the angle of the computer, the viewing distance and the glare off the screen can all contribute to visual stress and ergonomic symptoms (problems related to the working environment).

Now a days many people are working long hours on computers. Sadly some people never recognize the source of their symptoms or don’t realize they can be alleviated by good eye care and /or changes in their work environment.

To help yourself determine if you are experiencing symptoms related to your computer ask yourself if during or after computer use you experience any of the following:

• Headaches
• Double vision
• Dry or watery eyes
• Burning, itching or red eyes
• Frequently losing your place
• Sore or tired eyes
• Slow or difficulty focusing either far or near
• Discomfort with glasses or contacts
• General fatigue or irritability
• Numbness in hands or forearms
• Glare or light sensitivity
• Neck, shoulder or back pain

Here are some useful tips to make computer use easier on your eyes:

• Make sure your contacts and glasses are up to date. Annual eye exams by a doctor that asks you detailed questions about your working conditions and thoroughly examines the health of your eyes.
• Wear glasses or contacts prescribed for the appproprite computer working distance.
• In general a viewing distance of 20-28 inches is recommended.
• Take a 10-15 minute break every hour or two and glance up from the screen and focus some distant object every 5 minutes or so.
• Blink frequently and fully to prevent your eyes from becoming dry irritated and red. Note that some times drops or other treatments are advised for these problems.
• Keep your monitor away from windows to avoid excessive glare and use indirect lighing. It may be necessary to use a shade or drapes to block out bright sunlight and an antiglare screen for your monitor. In addition if you wear glasses an anti-reflective coating is advised.
• Place reference material close to your screen and at the same viewing distance to avoid unnessesary eye and head movements and changes in focusing distance.
• If possible set up your computer so the top of the screen is below your horizontal eye level and tilted back 10-20 degrees. Eyes works best when viewing 15 degrees downward.

You may be just interested in general recommendations on the following topics:

• Dry eyes
• Eye Examinations
• Computer glasses
• Computer displays
• Computer viewing distance
• Computer screen height and location
• Screen reflections - suggestions
• Lighting - suggestions
• Reference material location
• Keyboard and mouse location
• Chair
• Wrists
• Other

Or, if you are interested in information that is more technical and which explains mechanisms, check out this technical information.

The Eyes and The Visual System

• Refractive Errors
• Visual Acuity
• Accommodation
• Binocular Vision
• Presbyopia
• Lenses for Presbyopia
• Other Lens Options
• What Are Computer Glasses?
• Dry Eyes - Why?

The Work Environment

• General
• Lighting - Technical
• Reflections - Technical
• Computer Displays
• Workstation Arrangement

Some information provided by Dr. Sheedy.