There’s been a lot of hype recently about “3D displays.” Unfortunately, that’s all it is –– hype. This is because we are a long, long way from 3D display of anything but artificially generated materials.
A 3D display actually produces a 3D representation; that is, if you change your angle of view, what you see changes accordingly. Look at the display from the side, and you see the scene from the side. Likewise, if the display is turned 180 degrees, you’d be looking at the back of the scene being displayed.
Stereo displays provide a fixed perspective generated by providing two single-angle images of a scene that are designed to replicate the angles your eyes would achieve from the (single, unchangeable) desired vantage point. Changing your angle of observation will not reveal other portions of the scene in any way, nor will moving the display.
Stereo image technologies can become 3D when they use the actual angle of view of your eyes and change the stereo angle appropriately. This requires far more interaction with your eyes and physical orientation, not to mention actual 3D media to display. A half-measure most of us are familiar with can be observed in a game like MechAssault (XBox), where you can change your angle on the scene by moving your mech’s position or rotating its turret; here, we have the 3D media that is required, but we still don’t have the eye and body tracking that would give you the sense that you’re looking at something in full 3D.
There’s a huge marketing push right now to get the public to call stereo, “3D.” As proper geeks, we should resist this strongly, not only as a matter of incorrect (highly exaggerated) terminology, but to make it clear that there is a long way to go yet before we actually get 3D displays, and that we’re interested in getting them.
Quite aside from the issue that until or unless we’re all normally wearing display capable contacts or something similar that conveniently and as a matter of course feeds us dual images, the entire “here, put these glasses on” approach is a sorry mess. No matter what technology the glasses use.