Computer Vision

There is no reliable evidence to suggest that even long-term intensive use of computer screens (VDUs) is damaging to the eyes.  However, it is true that VDU users tend to complain of eye strain more than non-users.

This is likely to be due to fatigue through causes such as :

Insufficient and infrequent rest periods;

Incorrect positioning of the screen and /or documents;

Unsuitable lighting;

Poorly designed work area;

An uncorrected eyesight fault, such as long sight, short sight, astigmatism or presbyopia;

The eyes are not working together properly.

Any of these conditions could lead to fatigue; all can be overcome through good design of the working environment and by regular eye care.

Take Frequent Breaks

When you work at a VDU your eyes can be focused on the screen for long periods so it is important to take a brief rest and give your eyes a break every 30 minutes or so.  You should have sufficient space behind the screen for you to be able to look beyond it and relax your eyes.  If not, try looking out of a window for a few minutes.

Screen settings and positions

You should adjust your VDU to levels of brightness and contrast that you find comfortable.  Keep the screen clean and free of dust and fingermarks.  If possible, position it so that windows or other light sources are to the side rather than in front or behind it – if you can see a window or light unit reflected in the screen, move the VDU until the reflections disappear, or adjust blinds or curtains.

The surface of the screen should be between 45 and 100cms from your eyes and if you are working from copy documents, these should be placed at roughly the same distance to avoid continual re-focusing.




Try to eliminate as much glare as possible from the region around your screen.  This is not always straightforward, but as a general rule:

Office lighting should be set at a level which allows the documents and screen to be read easily.  Additional lighting, such as an Anglepoise lamp, may sometimes be necessary to achieve this;

Avoid an uncurtained window directly in front or behind your working position.  Any window reflected in the screen should be fitted with blinds or curtains.  Walls and desk surfaces should be non-reflective and neutral in colour.

Your legal entitlement as a VDU user

Since 1993 EC legislation has placed responsibilities on employers whose employees regularly use VDUs as part of their work.  These regulations are also designed to protect users who may work for an employer from home, or any other location that is not the employer’s main office.  If you are classified as a user, your employer must :

Provide a full eye examination, free of charge to you, when you commence VDU work and at regular intervals thereafter.

Provide a full eye examination, free of charge to you, if you are experiencing visual problems which may be due to working with a VDU.

Pay for a pair of basic spectacles, if it is shown that you require these specifically for VDU use, or an equivalent amount of money towards a pair of your choice.

Provide adequate breaks or changes of activity to reduce general visual fatigue;

Provide health and safety training relating to the work station.  Keep you informed about the regulations, particularly those relating to eyesight, rest breaks and guidance on work station minimum requirements.


Only a small proportion of users will need spectacles specifically for working at a VDU and the majority of these will be known as presbyopic.  Presbyopia affects us all as we get older.  Around the age of 45, people begin to find they lose the ability to focus on objects that are close up.  Spectacles with single vision, bifocal or varifocal lenses, can all be used successfully for VDU work.

Contact lenses are also suitable, but wearers should try to blink regularly which keeps the lenses comfortable.  When you concentrate on the screen for long periods, your normal blinking rate slows down.  Presbyopic contact lens  wearers may need additional reading spectacles.

Reflection-free lenses

Reflection-free lenses are well worth considering for VDU users.  As they eliminate almost all reflections, VDU glare is considerably reduced, providing clearer and sharper vision.

Note for employers

We can provide a full eye examination service for your employers.  During the eye examination we will examine the eyes of your employees thoroughly as well as test their sight for any visual anomaly.  Spectacles will only be prescribed if they are found to be a benefit.