BERKELEY, Calif., July 22 (UPI) -- Prolonged viewing of smartphones and other mobile stereo 3D devices may lead to visual discomfort, fatigue and even headaches, U.S. researchers say.
Study author Martin S. Banks, professor of optometry and vision science at the University of California, Berkeley, says the study consisted of a series of experiments on 24 adults.
The research team observed the interaction between the viewing distance and the direction of the conflict, examining whether placing the content in front of or behind the screen affects viewer discomfort.
The results demonstrated that with devices like cellphones and desktop displays that are viewed at a short distance, stereo content placed in front of the screen -- appearing closer to the viewer and into the space of viewer's room -- was less comfortable than content placed behind the screen, Banks says.
Conversely, when viewing at a longer distance such as a movie theater screen, stereo content placed behind the screen -- appearing as though the viewer is looking through a window scene behind the screen -- was less comfortable.
"Discomfort associated with viewing Stereo 3D is a major problem that may limit the use of technology," Banks says in a statement. "We hope that our findings will inspire more research in this area."
The study is published in the Journal of Vision.