Computer Vision Syndrome

Computer vision syndrome (CVS) most often occurs when the viewing demand of the task exceeds the visual abilities of the computer user. Because computer use is such a visually demanding task, vision problems and computer vision syndrome symptoms are very common. Most studies indicate that computer users report more eye-related problems than non-computer office workers. Studies also show that visual discomfort occurs in 75-90% of computer users.

Computer Vision Syndrome Symptoms

Here are some of the most common symptoms optometry patients will com in complaining of with computer vision syndrome:

  • Eyestrain
  • Headaches
  • Blurred vision (distance and/or near)
  • Dry and irritated eyes
  • Slow refocusing
  • Neck and/or backache
  • Light sensitivity
  • Double vision
  • After images and colour distortion

Reflections and Glare

The most common complaint of computer users is glare. Glare is created by improper lighting in the workspace. The two main sources are from light directly shining into the eyes (direct glare e.g. light from an overhead light) and from reflections from surrounding surfaces (reflected glare e.g. white paper).

Anti-glare filters which fit over the display screen are readily available. It makes it easier to read your screen and helps your productivity. It must be pointed out, however, that anti-glare filters themselves are not necessarily the entire solution to visual stress on computers.


Controlling the lighting of the workspace is critical in maintaining proper visual efficiency. Always turn off offending lights. If you notice glare on a screen from a light source, turn it off. Most offices have been designed for paper work and are overly lit for computer use.

Re-orient the work station so that bright lights are not in the field of view. Many people make the mistake of placing their computers right in front of a window, wishing to capitalize on a scenic view. This causes a lot of discomfort glare. The best solution is usually vertical blinds because they can be adjusted to allow for a view while re-directing glare.

Brightness and Contrast

Adjust the display settings on your computer so that the brightness of the screen is about the same size as your work environment. Ideally, your font size should be about 3 times larger than the smallest font size you can see from a normal viewing position. Black text on a white background is the best colour combination for your eyes.

Work Habits

Viewing a computer screen attracts the attention of the viewer more so than any paper object. Because of this, we ‘forget’ to blink. Blinking is an automatic reflex and beyond our conscious efforts. Studies have shown that there is less blinking while viewing a computer screen and this also causes dry eyes. One reason for this is because of the height of the monitor. Because it is in a higher field of view, the eyes are wider open. This creates a wider gap between the eyelids making blinking more of an effort. By lowering the screen, the size of this gap is reduced and allows the lids to blink easier. Also the use of artificial tears can help a great deal. Ask your optometrist which brand he recommends.

When office work still involved typewriters, pencils and paper, there was a great deal of physical activity in the work area. Hands were moving in all directions to insert paper, return the typewriter carriage, grab a pencil or turn a page. Office workers were getting up to make copies, deliver papers to another office, look for carbon paper and other types of physical tasks. With the integration of computers into the workplace, much of these movements are accomplished by the push of a button. Our bodies are designed for movement and should be moved routinely.

This holds especially true for the visual system. Our eyes have many muscles associated with them. If these muscles are ‘stuck’ in the same position for extended periods of time, they will adversely affect vision. Taking visual breaks is a very easy thing to do because they do not involve leaving the desk and do not have to be long in duration.

A micro break consists of simply looking into the distance every 10-15 minutes. This should be done for 15 seconds.

A mini break should be performed every 30 minutes and involves closing the eyes for about 2 minutes.

A maxi break should follow along with your routine work breaks where you get up and move around for at least 15 minutes. This should be done every 2 hours.

This scheme will allow the eyes to change their viewing condition regularly and still allow the worker to produce effectively.

Computer Glasses

Most prescribed eyeglasses are for general purposes: driving, movies, TV, shopping, allowing you to perform a variety of tasks. However, there are also task specific lenses which are made for you to do a specific task. Computer glasses are designed with these types of lenses.

A ‘computer’ prescription is any lens which allows you to see the display screen clearly and comfortably. They do not, however, necessarily allow clear vision at any other distance. There are a number of combination lenses which allow for this type of vision. If your bifocals or multifocals don’t give you much comfort, consider a pair of computer glasses.

Anti-Reflective Coatings

A normal eyeglass lens only allows 92% of light to pass completely through it. The remainder of the light is reflected by the front or back surface. However, a coating applied to the front surface of the lens cancels out this reflection and allows 99% of the light to pass through. This has a double benefit to the general eyeglass wearer. Firstly, it allows your eyes to be more visible to someone looking at you. Secondly, the anti-reflective coating, by allowing more light to pass through them, also makes the view through the lenses more distinct.

This is most noticeable by viewing lights at night, whereby you might normally notice glare around street lights or oncoming headlights. The anti-reflective coating allows lights to pass through the lens without the extra glare or distortion. These lenses make all types of viewing easy on the eyes.

Where to buy Computer Glasses?

Always try to avoid buying over the counter reading glasses for use on a computer. An accurate eye glass prescription is essential if you want to get the full benefits of computer glasses. It’s best to purchase this eyewear from a trained eye care professional like an optometrist.

Before scheduling your appointment, measure the distance from your computer screen to the bridge of your nose. This measurement will help your optometrist prescribe the optimum lens power for your computer glasses.

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