Lighting, glare and reflection
Lighting
Place the monitor to the side of the light source/s, not directly underneath. Try to site desks between rows of lights. If the lighting is fluorescent strip lighting, the sides of the desks should be parallel with the lights. Try not to put the screen near a window. If it is unavoidable ensure that neither the screen nor the operator faces the window.
If the monitor is well away from windows, there are no other sources of bright light and prolonged desk-work is the norm, use a low level of service light of 300 lux. If there are strongly contrasting light levels, then a moderate level of lighting of 400-500 lux may be desirable.
Glare and reflection
It is important to detect the presence of glare and reflection. To determine whether there is glare from overhead lights, sit down and hold an object such as a book above the eyes at eyebrow level and establish whether the screen image becomes clearer in the absence of overhead glare.
To detect whether there are reflections from the desk surface, hold the book above the surface and assess the change in reflected glare from the screen.
You can eliminate or reduce the influence of these reflections in a number of ways:
- Tilt the screen (top part forwards) so that the reflections are directed below eye level.
- Purchase an LCD screen.
- Cover the screen with a light diffusing surface or anti-glare screen.
- Negative contrast screen (dark characters on light background) will reduce the influence of these reflections.
If you experience eye discomfort when using a bright screen you should make the following adjustments:
- Turn the screen brightness down to a comfortable level.
- Look away into the distance in order to rest the eyes for a short while every 10 minutes or so.
- Change the text and background colours. We recommend black characters on white or yellow background, or yellow on black, white on black, white on blue and green on white. Avoid red and green and yellow on white.
(sourced from the University of WA website)