American Optometric Association Sees No Health Risks In 3D Viewing

Nintendo’s introduction of the 3DS game system next week could have a profound effect on children’s vision in the future, but not in the way Nintendo has warned, said a panel of optometry experts who want to use 3D content to screen for potential vision problems.

The American Optometric Association and the 3D@Home Consortium announced in Manhattan this week a partnership to promote vision health and to “improve the understanding of 3D viewing as a safe and appropriate technology for all viewing audiences.” According to optometry experts speaking during a panel on 3D vision and health, two to nine million Americans are unable to view 3D images, and that limitation could be an indication of treatable vision disorders. The AOA wants to use 3D technology to identify those problems and encourage parents to get early treatment to possibly reverse the disorders and prevent learning issues down the road.

That’s in stark contrast to the warnings Nintendo posted on its website last December (CED Dec 30 p6) warning about 3D technology’s potential harm to children’s eyesight. Children’s vision under the age of six is still at a developmental stage, the company said, saying the different left and right images could potentially impact the development of their vision. It suggested that parents limit 3DS playing by kids under six to 2D only, it said. The company also recommended that 3DS players take a break every 30 minutes to avoid eye fatigue, and warned that if players felt ill while playing they should stop immediately. Sony Computer Entertainment America issued a similar warning about stereoscopic 3D game play on the PS3 while updating its service last summer (CED July 14 p5).

According to the AOA panelists, though, children under the age of six should be exposed to 3D as an early-detection tool for possible vision problems. Jim Sheedy, director of the Vision Performance Institute at Pacific University in Forest Grove, Ore., told Consumer Electronics Daily 3D presents no risk to children under six and that children are able to discern 3D as soon as their eyes are able to function together -- anywhere from six months to a year old. Sheedy estimated 70-80 percent of the disorders preventing people from seeing 3D images could be corrected with proper diagnosis and treatment. Some of the disorders that can prevent people from seeing 3D images include binocular vision impairment, diabetes or even issues associated with contact lenses that can alter polarization, according to panelists at the symposium. “We'll know more a year from now,” Sheedy said, citing an eye treatment clinic the Institute plans to open in June.

The Vision Performance Institute did a study with the 3D@Home Consortium and Intel to learn about 3D in the home theater environment. In the study, 205 adults were randomly assigned to 2D or 3D viewing. The 3D viewing group “quite clearly” experienced more symptoms in the study than those who didn’t, and “we need to figure out why,” Sheedy said. The next step is to assess the characteristics of the people who had more adverse effects, he said.

Acknowledging that research into 3D and consumer use is “still very early,” Sheedy said a few findings have emerged. Virtual 3D, what is created on a two-dimensional display, is setting up a visual stimulation that’s different from what we experience in the real world, he said. In the virtual 3D world, eyes have to “learn a new trick,” which is to converge without accommodating as they do in the real 3D world, he said. “Some people have more problems with a new trick, and that’s why they have problems with 3D,” he said. There are “more eye and disorientation symptoms” caused by 3D viewing, he said, and “people are getting vertigo problems, dizziness, and nausea. We need to figure out why.” Causes could be vision-based or vestibular -- that is associated with inner ear disorders, he said. “It could be we're just creating a more immersive and realistic experience for people,” he said. “Lots of people don’t like to take carnival rides where they spin around a lot because it’s more immersive,” he said.

Future 3D research activity at the institute will address who has problems viewing 3D displays, establish a way to measure the quality of the 3D experience, determine whether subjects perceive a disconnect between accommodation and vergence in 3D, develop clinical testing instruments and a testing paradigm for 3D viewing, and study the relationship between vertigo and 3D sensitivity. It also plans to determine whether in fact kids’ problems with viewing 3D can be an effective screening tool for underlying vision disorders, Sheedy said.

The collaboration between the two organizations will present an interesting challenge for hardware makers, some of whom, like Nintendo, have taken a guarded, legally protective, approach to 3D and health. Despite a lot of media attention last year, the Samsung website continues to list an extensive disclaimer about possible reactions to 3D viewing including warnings about epileptic seizures, altered vision, lightheadedness, dizziness, involuntary movements such as eye or muscle twitching, confusion, nausea, loss of awareness, convulsions, cramps and/or disorientation.

Dan Schinasi, senior marketing manager at Samsung, who attended the AOA event, was cautious about the topic of 3D and health, citing publicity Samsung has received about its 3D warnings. Demonstrating the fine line TV makers have to tread on the safety issue, Schinasi was quick to tell us that 3D TVs aren’t meant to be a diagnostic tool, “but if you happen to buy a 3D TV and your child or your neighbor isn’t seeing 3D correctly, that’s a cue.” If poor or no 3D vision leads to an eye exam that exposes deeper issues, then “not only can someone enjoy 3D TV, but it can be an enhancement to their learning at school,” he said.

For the AOA and its 36,000 members, the 3D opportunity offers a way for optometrists to perform more screenings. “3D movies have a new dimension -- protecting eye health,” said Michael Duenas, associate director of health sciences and policy at the AOA during the panel. Seven percent of children under the age of six get vision screenings, and those are primarily quick tests using the 150-year-old Snellen eye chart that only has a 27 percent sensitivity rating, Duenas said. “That means most kids being tested are being told they don’t have a vision problem,” Duenas said, resulting in a “high rate of false negatives.” They can’t “maintain focus, can’t read, can’t comprehend what they're reading and they fall behind,” he said. Parents are told their kids passed the screening test, which wasn’t a comprehensive eye exam, and they rule out vision problems as a possible cause of poor classroom performance. Thus, 3D fits into the picture by indicating which children can see clear and aligned images, Duenas said. “If one image is blurred or misaligned, the brain will learn to suppress that image,” leading to amblyopia or lazy eye syndrome, he said. Also, misaligned vision caused by eye muscle problems can result in intermittent, constant or alternating difficulties with 3D vision, he said.

Regarding the concern that some parties have expressed -- including 3D hardware makers -- about dangers that prolonged or frequent viewing of 3D content can create for user vision, AOA members at the press conference said there’s no evidence supporting that conclusion. “Should we be looking at it? Yes,” said Sheedy. “If we had any reason to suspect that, the AOA wouldn’t be here now,” he said. At the same time, he'd have a hard time justifying the cost of setting up a study to monitor long-term effects of 3D viewing. “Is there a limit to how long a child should view 3D? Yes,” he said. “How long? We don’t know,” citing similar research done with computers in the classroom that also yielded no results for long-term risks. There, the negative result of long-term use was “obesity,” he said. “I think there is a limit with 3D, but let’s use sound judgment,” he said.