For some, 3D movies a pain

Chicago, January 11: Movie buffs and sports fans looking to 3D televisions for the ultimate home theatre experience may want to get their eyes checked first – or risk a 3D headache, US eye experts said on Saturday.

The growing popularity of three-dimensional movies such as James Cameron’s Avatar – now a $1bn box office hit – has inspired a crop of 3D TV sets, unveiled this week at the International Consumer Electronics Show in Las Vegas.

And while new digital 3D technology has made the experience more comfortable for many, for some people with eye problems, a prolonged 3D session may result in an aching head, they said.

“There are a lot of people walking around with very minor eye problems, for example a minor muscle imbalance, which under normal circumstances, the brain deals with naturally,” said Dr Michael Rosenberg, an ophthalmology professor at Northwestern University Feinberg School of Medicine in Chicago.

He said in a 3D movie, these people are confronted with an entirely new sensory experience.

“That translates into greater mental effort, making it easier to get a headache,” Rosenberg said in a telephone interview.

In normal vision, each eye sees things at a slightly different angle.

“When that gets processed in the brain, that creates the perception of depth,” Dr Deborah Friedman, a professor of ophthalmology and neurology at the University of Rochester Medical Centre in New York.

“The illusions that you see in three dimensions in the movies is not exactly calibrated the same way that your eyes and your brain are. If your eyes are a little off to begin with, then it’s really throwing a whole degree of effort that your brain now needs to exert.

“This disparity for some people will give them a headache,” she said.

—Agencies