WARNING: 3D Video Hazardous to Your Health headline is a bit sensational. But it is not the only one this kind of headline.
The 3D Video Hazardous to Your Health article tells that prolonged viewing of 3D video may be even more harmful than the consumer electronics industry wants you to know. Especially for children. Nintendo unveils 3DS and quickly follows-up with a statement about dangers to children under 7 playing with the company’s new portable gamer. Samsung has also given warnings on their 3D TVs. These warnings come after years of industry spin and cover ups.
Do you remember in the mid-90s when virtual reality headsets were going to be the next big thing? I remeber that time well. Do you wonder why the whole technology just sort of… went away? With a working VR Headset almost ready for market, Sega had the product tested by a third party lab, The lab at Stanford came back to Sega with dire warnings about the hazards of prolonged use of this technology. SRI warned Sega: “You Cannot Give This To Kids!”. The results of SRI’s research have been published and there is an unclassified document from the defense department of Australia that says there are a variety of “…unintended psychophysiological side effects of participation in (3D) virtual environments.”
Problems of stress on the visual system have been most obvious in HMDs. While poor engineering design or incorrect calibration for the user can be a source of visual stress, but there are also other problems. Current stereoscopic VR displays provide an illusion of depth by providing each eye with a separate 2D image on a fixed focal plane. The mechanisms of binocular vision fuse the images to give the 3D illusion. Because there is no image blur, the eyes must make a constant accommodative effort. But at the same time the images stimulate a changing vergence angle with changes in apparent depth, so that the normal cross-linked relationship in normal viewing system is disrupted. The problem applies to all stereoscopic displays. Within certain limits the visual system can adapt. What has been shown in several studies is that short-term exposure to virtual enviroments with stereoscopic displays has produced changes in heterophoria (latent squint), where the visual axes of the eyes deviate from their usual position. These objective changes are associated with reports of subjective symptoms such as blurred vision, headaches, eyestrain or momentary double vision. Longer exposures result in greater severity of symptoms overall.
Stereoscopic vision begins developing when we first start using our eyes and is generally considered complete by the time we’re around six years old. There is a condition in children called strabismus or lazy-eye; it’s an abnormal alignment of the eyes in which the eyes don’t focus on the same object and depth perception is compromised. Anyone who learned the technique that allows them to peer into stereograms has taught themselves a temporary form of lazy-eye. The modern digital 3D effect using glasses makes this same effect effortless. Your eyes are invited or forced not to properly focus in order to get the full effect of eye-popping 3D. Children under seven are at risk of strabismus.
Going to a 3D movie each month probably won’t hurt anyone’s vision, especially adults. Some people report being temporarily disoriented when walking out of a 3D movie. The warning suggests that some 3-D TV viewers could become so disoriented that they could fall and hurt themselves. Going to the odd 3D movie probably won’t hurt anyone unless you fall when walking out of the movie theatre. Going to a 3D movie each month probably won’t hurt anyone’s vision, especially adults.
However, if we introduce the 3D effect into the home, we dramatically increase our exposure. We could sit at home with our new 3D HDTV and watch non-stop real or upconverted 3D for days. Marathon video game sessions in 2D are already difficult on the eyes, how about a marathon video game session in 3D? Some people sit around watching 6 or more hours of TV a day. What happens when that becomes 3D TV viewing?
Samsung issues warnings about 3-D TV: Pregnant women, drunk people and “those who are sleep deprived” should not watch 3-D television because of potential health issues, electronics manufacturer Samsung says on its Web site. The company also says people at risk for stroke or epileptic seizures should consult a medical professional before watching TV in three dimensions. The warning suggests that some 3-D TV viewers could become so disoriented that they could fall and hurt themselves. “Viewing in 3-D may cause disorientation for some viewers,” the warning says.
