You won't shoot your eye out with Nintendo's upcoming glasses-free 3D handheld, but you might cause irreparable ocular damage if you're six or younger and play in 3D mode.
That's because your eyes are still developing through childhood, and still learning to see the world courtesy stereopsis--the way your eyes capture two discrete images for the brain to render as one in 3D.
Nintendo's 3DS can display images on one of its two screens in true 3D without the need for special eyewear. To access 3D mode, all you need to do is slide a switch, which shifts the 3D "depth" of the image from "off" to "full."
"We will recommend that very young children not look at 3D images," said Nintendo America president Reggie Fils-Aime. "That's because, [in] young children, the muscles for the eyes are not fully formed."
If that sounds familiar, it's because Fils-Aime actually said it six months ago, just after the 3DS debuted at E3.
Nintendo Japan recently issued a new cautionary note on its website, reiterating the warning in anticipation of its upcoming Nintendo World event during which the 3DS should be publicly available to demo. Nintendo let thousands of gamers fiddle with the handheld at E3 last summer, but E3's a trade show for "industry professionals." I don't remember seeing little kids in any of the show halls.
It's not clear from Google's English translation of the page whether Nintendo intends to block kids six and under from playing the system at the event, or how they'll verify a player's age. For that matter, it's not clear how parents will block kids from accessing 3D mode when the handheld launches in March. Will Nintendo offer a "parental control" option that disables the effect? If they don't--and it's hard to see how they would, given the 3DS's hardware-based slider control--they'll be missing an opportunity, possibly crucial, to offer parents a safety valve.
The warnings aren't just for kids, either. There's the usual bit about taking breaks and ceasing to play if you feel sick (as if we needed to be told), but also a section warning that for people who have difficulty "seeing in stereo," the 3D effect may be "invisible." No harm in advising you try before you buy then.
If you want to know more about the science behind stereoscopy, see "Could 3D Video Gaming Wreck Your Eyes?" Online audio-video magazine Audioholics caused a stir this summer when it wrote "the truth is that prolonged viewing of 3D video may be even more harmful than the consumer electronics industry wants you to know."
The verdict's still out on 3D's long term, prolonged use impact, but if Nintendo's 3DS achieves even a fraction of the Nintendo DS's success (over 140 million units sold worldwide) we'll probably know more in short order.
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