If you sat down a few weekends ago to see the final chapter of the Harry Potter film franchise or munched popcorn a couple of years ago while everyone else in the theater was flipping out about the "phenomenal graphics" of "Avatar," you may not have noticed how fatigued your eyes were getting.
A new study conducted at the University of California, Berkeley, has revealed that watching stereoscopic 3-D films causes visual discomfort, fatigue and headaches.
The problem, researchers say, comes from the strain of "attempting to simultaneously focus on the screen itself as well as objects that appear to be located either in front of or behind the screen."
"When watching stereo 3-D 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, professor of optometry and vision science at UC 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."
The study conducted involved 24 adult subjects who watched 3-D content on both smaller, personal computer-sized screens and on the standard theater-sized screens.
The study revealed that 3-D content viewed on the smaller screens leads to more difficulty focusing on objects located in front of the screen. Viewing 3-D content on the larger screens revealed that the audience experienced more discomfort while focusing on objects behind the screen.
"Discomfort associated with viewing stereo 3-D is a major problem that may limit the use of the technology," Banks said. "We hope that our findings will inspire more research in this area."
The UC Berkeley research team is planning further testing with a larger group of subjects from a wider array of demographics, such as children, who were exempt from the initial testing process, and they hope additional findings may someday be used to "establish guidelines for the positioning of viewers relative to 3-D displays."
So while you may be a fan of 3-D films now, just remember how cool you thought the Green Lantern's suit looked onscreen when you're paying to get your eyeglass prescription updated yet again.