Computers and Your Eyes: Ergonomics

The new year has started, and that means back to work for everyone.  For many of Americans, that means back to the computer screen, spending 8-12 hours a day with non-stop computer use.  And then, yes, we go home and typically unwind with computer use (or iPad or cell phone).  So what is all of that computer time potentially doing to your eyes?  This month I am devoting multiple posts to computer vision -- how to maximize your computer vision and comfort, and possible solutions for common computer complaints with the eye.

Look for posts in the next few weeks devoted to solutions for these common computer issues:

• Tired eyes, eye strain
• Dull pain behind the eyes
• Double vision
• Eyelid twitching
• Blurry vision, either at the computer screen, or driving home at the end of the day
• Blurry vision that clears between blinks
• Red eyes, burning, stinging, watering, dryness

Let's start with just a general review of your workplace ergonomics.  It's amazing what a difference the right set up can make!

1) Screen Height

Advice: The top of your computer screen should range from at eye level to 15 degrees below your eye level when you are sitting straight at your desk.  If you have a large monitor, at eye level is advisable. Smaller monitors are better for 15 degree below eye level screen height.

Why?  The goal is that your neck can be held straight, without needing to tilt the chin up or down.  If you wear progressives, this will put your eye naturally looking through the computer portion of the lens.  Other benefit?  Your eyelids will be able to droop partially closed.  If your screen height is above eye level, you will have to hold your eyes open very wide!  This leads to much more dryness issues by the end of the day!

2) Distance to your Screen

Advice: Set your computer monitor about extended arms length away from your seat.  Typically the distance is 2-3 feet.  

Why?   The closer your monitor screen is to your person, the harder your eyes are going to have to work.  A longer working distance allows for more comfortable viewing distance, as well as a wider field of view to work with, which means less head movement for you when you are reading across the screen.

3) Lighting

Advice: Natural lighting, such as window light is great, but should be dimmed so that the brightness from surrounding lights is as close as possible to the brightness of the screen.

Why? Ambient brightness can create more glare and reflections on the screen.  If your surrounding lighting is about the same brightness as your screen, the world will seem more natural.  There will be less discomfort caused by the difference between screen brightness and world brightness.  Try dimming your computer screen to match workplace brightness if you can't change your workplace lighting.

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4) Glare Reduction

Advice: Avoid any external lighting reflecting onto computer screen by moving position of lamps, or covering windows if they provide direct glare.  A yellow filter over the screen can also be used for glare reduction.

Why? Yellow filters out blue light waves, which is the predominant wavelength of electronic light sources.  Therefore a yellow filter will cut glare from your screen, but also enhance the contrast of black writing on a white screen.  A win-win.

5) Vents and Fans

Advice:  Do not have air vents or fans putting direct air flow on your face.

Why?  Direct air flow will dry your eyes out even faster, creating blur, redness, and discomfort!