Most computer screens have a poor light output themselves so bright lighting in the room will simply overpower the images on the screen. However, you do need some background light because the contrast between a dark room and the words on the screen makes it hard for the eyes to adjust from one to the other and is therefore very tiring. Since light levels from the window vary from hour to hour, you want to be able to adjust the room light to make it as comfortable as possible for you while you work and this is an instance where dimmer switches will help. Desk lamps are sometimes helpful.
When you are setting up the lighting for computer work, check that there are no reflections on the screen. What usually happens is that the operator gets so used to reflections that he or she doesn’t notice them, but if they do exist they are an extra strain on the eyes and are distracting. If you can see the ceiling fixtures reflected in the corner of the screen or if there are bright spots of glare from the general room lighting, then a dimmer will help to reduce them; better still, alter the lighting in the room or the position of the computer screen so as to eliminate them.
Fixed spot lamps and ceiling lights are the least flexible, although spots on a track can be adjusted. If the ceiling is high enough and the room small enough, any ceiling fitting will probably be out of sight of the screen anyway. Shiny objects such as mirrors and glass-covered paintings should not be hung in a computer room.
Remember that lighting is just as important for children’s computers as it is for adults, if not more so.