NOTE: Bah, I was messing around and I deleted it by accident. =/

[This entry is a portion of an article from this month's issue of Game Informer. Most of this information was revealed at E3.]

"The human eye is only capable of capturing two-dimensional images. However, we perceive the world around us in three dimensions because we have two eyes. If you blink - looking through each eye alternately - you'll notice that objects closer to the foreground seem to shift more than objects in the background. This is because each eye sees the world from a slightly different perspective. your brain takes these two slightly varied images and calculated the distance of objects in front of you, which allows you to perceive the world around you in three dimensions. The 3D illusion takes advantage of this mind trick by presenting images to each eye in which objects have been shifted slightly.

"English inventor Sir Charles Wheatstone discovered the 3D optical effect in 1838 when he invented a device similar to modern Viewfinders. Current 3D displays present these dual images at the same time, but for the effect to work, you must wear glasses that filter one of the extra images from each eye. With each eye receiving a slightly different picture, the brain does its calculations and perceives certain objects to be closer than others. So how does Nintendo's 3DS pull off the same trick without glasses?

"The top screen of the 3DS still stacks two images on top of on another like most 3D-ready displays, but instead of requiring the viewer to wear special glasses, a parallax barrier has been placed on top of the LCD display. This parallax barrier is a thin layer of material featuring a series of precise slits that essentially angle the two images in different directions, one towards each eye. This technology isn't new; Sharp has been experimenting with this kind of display for nearly a decade. The problem is that parallax barriers only allow for a very narrow viewing angle - sit to far to the side and all you see is a blurry mess. This is bad news if you're trying to sell a family of four a 60-inch television, but works flawlessly if you know that only one person will be standing in front of your product at any given time."

Reeves, Ben. "How it all works." Game Informer, August , 2010, 18.