Watching 3D movies can "immerse" you in the experience, but it can also lead to visual symptoms and even motion sickness. Symptoms related to 3D viewing are affected by where you sit while watching, and even how old you are.
Researcher by Shun-nan Yang says, "Younger viewers incurred higher immersion but also greater visual and motion sickness symptoms in 3D viewing. Both problems will be reduced if a farther distance and a wider viewing angle are adopted."
When two groups of participants watched the same film–one group in 2D and the other in 3D–21% reported symptoms of motion sickness while watching the movie in 3D. Movies shot with handheld cameras often produce the motion sickness as well. For younger study participants blurred vision, double vision, dizziness, disorientation, and nausea were all more frequent and severe when watching the movie in 3D.
As 3D movies become more common, including on home screens, there are reports of visual and other symptoms among 3D viewers. Vision and orientation symptoms related to 3D viewing may be related to a "mismatch" between focusing and converging the eyes.