'Using a PC is bad for your eyes'

Scientists have discovered that using a computer monitor can be bad for your eyes.

Researchers from Ohio State University found that people who squint at their PC's monitor – looking at complex or detailed information onscreen, for example – are prone to eye strain and a condition known as 'dry eye'.

The 'dry eye' which results from a lack of blinking isn't debilitating but can be irritating and uncomfortable.

Computer users often squint at their monitors to cut the brightness or to bring small details into clearer focus, according to the university's scientists, and people may not be aware they're squinting.

According to the scientists, most people who use monitors will squint, which then causes them to blink less. Even low-level squinting causing blink rates to half from 15 blinks a minute to 7.5 per minute, the researchers found.

The Ohio researchers studied 10 volunteers' blink rates using electrodes attached to an electromymogram and asked them to focus on a black dot on a screen, squinting to varying levels. When volunteers were at their most squinty, blinking reduced to four blinks per minute.