Giz Explains 3D Technologies

Giz Explains 3D Technologies
Last week, CNN’s attempt to display the future of TV news ended up making 3D look like the gimmick that it is. Yep, 3D is a gimmick, most associated (outside of CNN) with those stupid glasses designed to fit Blockheads from Venus. But as you know, there are many different scientific approaches dedicated to tricking you into thinking bullets – or other deadly projectiles such as children – are popping out of the screen and coming right at you. Here’s a quick and dirty guide to 3D magic.

Most 3D operates on a single basic principle – tricking our dumb, binocular brain into interpreting a 2D image into one with depth. The most basic way to do this is stereoscopy, which is essentially showing a slightly different image to each eye which the brain mashes together into a 3D image. We’ve broken up the million different ways to do 3D in a few broad categories.

Stupid Glasses
It’s easiest to do stereoscopic images with glasses or other nerdtastic eyewear to change how you see stuff – hence there are a lot of variations in 3D glasses tech.

• An anaglyph image is the old school 3D we all know and got headaches from: An image has two different colour layers, one for each eye, with slightly different perspectives and when we look at them through those awesome plastic glasses (usually with red and blue lenses) that block one layer in each eye, our dumb brain takes the resulting separate image from each eye and mashes them together to make a 3D scene in our head.

Polarised 3D glasses

The Pulfrich effectMarried with ChildrenThanks David!

ChromaDepth is perhaps the fanciest glasses tech using micro-prisms and whatnot (hello red and blue again), but all it essentially does is slightly shift the way colours are perceived in each eye, so they see different things and boom, 3D. The major limitation of the tech is that if you change the colour of an object, you also change how its depth is perceived, since it’s all based on colour. (Check out the video above, done in ChromaDepth, to see what I mean.) [Thanks David!]

they’re so ridiculousway more

No Glasses Required
OK, so you don’t wanna wear glasses. No problem – you just move the one-image-per-eye dance to the display itself.

you see it in Sharp TVs for instanceworks a lot like polarised glasses

form of parallaxan array of spherical convex lenses

• Another form of parallax is continuous-motion parallax. Here, HoloVizio’s system dumps pixels in favour of voxels, which can project multiple light beams in multiple directions simultaneously.

3D in 3D
So far, we’ve just talked about 2D images on a flat screen, which your brain is fooled into thinking are three-dimensional. The other side is creating images in real 3D – you know, meatspace. Still, most of them make use of lighting and projection tricks too.

called a light-field display

Japanese researchers’ new plasma-laser hologrammy device

• Heliodisplay actually creates a surface in mid-air to project an image onto, which allows you to do the “Help me Obi-wan Kenobi” type of floating holograms that look 3Dish, though they’re actually planar (2D) images. Yep, it’s expensive.

FAKE FAKE FAKE
There are lots of suggested 3D images out there that aren’t any kind of real 3D – video games are, of course, the most obvious. But why pick on them when you can pick on CNN?

• Sorry Wolf, but we gotta hit people with the truth: CNN’s “holograms” are totally fake. We already explained this before, but no one was projected in front of Wolf Blitzer. He was looking at a wall. What we saw at home as computer-generated: A bunch of HD cameras filmed the hologramee from all sides, computers crunched that data and delivered whatever angle the studio camera needed at the time. As long as the source angle was synced to the studio angle, it looked, to viewers at least, like a 3D “hologram”. Nice try, Wolfie. Call us when you score an R2 unit.

– With Reporting by Seung Lee. Post updated with two additional 3D technologies.