In the 1950s and 60s cheap and harsh fluorescent lights were sometimes used, which could cause eyestrain.

If a display is misconverged, images will have a color halo around them and will eventually cause eyestrain.

Watching TV in a lawn chair in a dark room may cause eyestrain.

However, focusing your eyes too long on any one thing can cause eyestrain, a temporary (but irritating) problem.

Reading microfilms on a machine for some time may cause headache and/or eyestrain.

Geordie had the man up the foremast relieved every hour because the glare from the sea could cause eyestrain.

Video screens can cause eyestrain from prolonged viewing.

But that approach creates flickering that causes severe eyestrain when a person views the screen at close range - as most computer users do.

Working on a computer, he said, caused eyestrain, neck aches and the feeling that his brain was "turning to mush."

However, the lack of protection from impact, ultra-violet, infrared and blue light caused severe eyestrain and eye damage.