The root cause may be the demand on our eyes to focus on the screen and simultaneously guage the depth of the content.
Scientifically referred to as vergence-accommodation, this conflict and its effect on viewers of stereo 3D displays are detailed in a recent Journal of Vision.
"When watching stereo 3D displays, the eyes must focus - that is, accommodate - to the distance of the screen because that's where the light comes from," said Martin S. Banks, who led the study at University of California, Berkeley.
"At the same time, the eyes must converge to the distance of the stereo content, which may be in front of or behind the screen," added Banks, professor of optometry and vision science, according to a California statement.
"Discomfort associated with viewing stereo 3D is a major problem that may limit the use of technology," he said. "We hope that our findings will inspire more research in this area."
With the explosion of stereo 3D imagery in entertainment, communication and medical technology, the study authors proposed guidelines be established for the range of disparities presented on such displays and the positioning of viewers relative to the display.
