The eyes will usually recover very quickly when allowed to rest. Computer monitors should have both a contrast and brightness control switch. Maximum contrast and minimum brightness usually produce the least strain on the eyes. Adjust your monitor for maximum personal comfort. If characters on the screen appear to be fuzzy or out of focus, it may not be faltering vision at all.
Some monitors lose their character clarity due to technical problems.
Copy stands should be placed at the same height as your monitor. This allows the eyes to more easily scan back and forth at the same focal distance, rather than looking down on the desk and then readjusting back to the monitor. This reduces unnecessary repetitive motion which causes fatigue. Light and Glare Light striking the screen and causing excessive glare may come from many sources in your area. Situating your monitor directly in front of a large window may create strong backlighting conditions which can result in squinting and eye strain.