A View from David Zax
Does 3D Hurt Your Eyes? Yes, Says Science
Now how do we fix the stereoscopic mess we’ve gotten ourselves into?
The plural of anecdote is not data, goes the saying. So while I may think, and you may think, and everyone you know may think, that the explosion of 3D–in movies, in TVs, in phones, in video game devices–is an annoyance and an eyesore, that’s not enough. Fortunately, though, there are scientists out there collecting data–and they’re scientifically proving, in essence, that for many people, 3D hurts your eyes. What’s more, they’re figuring out exactly why.
The paper in question is “The zone of comfort: Predicting visual discomfort with stereo displays,” and it was recently published in The Journal of Vision (we came to it via TechCrunch). Essentially, it confirms with data many of the suspicions one of its authors, UC Berkeley’s Martin Banks, conveyed to Technology Review back in April of 2010. As we explained back then:
“To look at a three-dimensional object in real life, a set of eyes must do two things. Firstly they must ‘verge’–rotate slightly inward or outward so that the projection of an image is always in the center of both retinas. Secondly, the eyes must ‘accommodate’–change the shape of each lens to focus the image on the retinas.”
But artificial 3D fakes out this natural process–we focus on the screen, but our eyes verge where the 3D object appears to be in space. As Banks said back then, “In 3D, the natural linkage between vergence and accommodation is broken.” Now, Banks is back with data. His team experimented on 24 adults, with varying 3D set-ups. (Actually, they performed three separate but related experiments, the intricate details of which you can find in the full PDF of the paper.) The team found that at a short distance–with your computer screen, say–objects that pop out towards you cause greater eyestrain. But at a movie theater, or in another situation where the screen is at a great distance, the opposite holds–objects that seem to recede behind the screen cause greater eyestrain. This holds true even for “glasses-free” 3D experiences, Banks tells Technology Review.
The paper almost treats 3D like a strain of some virus that can’t be contained, only treated. The assumption appears to be that 3D is here to stay, and that as good epidemiologists we must do what we can to mitigate the damage it inflicts. The authors close their paper, for instance, with four “guidelines for minimizing discomfort” (the abolition of 3D is not one of them). In the end, lessening the toll of the 3D epidemic may require scientists, cinematographers, and device manufacturers to all work together. As the authors observe, after many conversations with stereo cinematographers, it became clear that there wasn’t even an industry standard on exactly how 3D content should be produced.
The World Health Organization and the Motion Picture Association of America might want to hold a joint conference as soon as possible, and they might do well to hold it on the campus of Berkeley.