The placement of your monitor on your desk is key to helping prevent excessive fatigue, eye strain, and back or neck pain. Placing your monitor either too close or too far away from you can cause all sorts of problems. A monitor that is too far away will force you to lean forward, thereby resulting in back or neck pain. A monitor that is too close can cause eye strain and back problems as a result of adopting awkward postures. To make sure your monitor is situated in the right position, sit at a comfortable distance from the monitor, where you can easily read all the text with your head and torso in an upright posture and your back supported by your chair.
Having to look up or down or to the side to see your monitor can also cause problems. The best solution is to place your monitor directly in front of you, with the top of the monitor at or slightly below eye level.
Finally, even the perfect monitor setup can cause eye strain or fatigue if you have to look at it for long periods of time. Most people do not blink as often as they should when they look at a monitor. To counteract this, make opportunities to rest your eyes, look away at periodic intervals, blink often to moisten your eyes, and if possible, do tasks for a while that do not require the use of a computer or looking at a screen.