> > Finally, don't expect 3D TV any time soon. Existing televisions can do the red/green type of 3D, which looks terrible anyway, but they can't project polarized light and aren't likely to in the near future.

> Incidentally, polarising computer monitors have been on the market for a year or two, and I believe TVs that don't require glasses at all have produced working prototypes, though I can't for the life of me work out how they work. Sky is intending to broadcast the 2012 Olympics in London with a 3D option, so apparently they think 3D TVs will be in homes by then...

Resurrecting an old thread because I've not been around in a while, and strangely have been doing a ton of research on this topic for my job lately.

There are a couple of different ways to do 3D in the home that don't require red/green or red/blue glasses.

There is a glasses-based setup from NVidia right now that doesn't use polarized light or red/green anaglyph; instead it relies on a 120Hz monitor (which are becoming more common). The video card displays alternating images for the right and left channels, each at 60Hz. So in 1/120th of a second it displays a right image, then the next 1/120th of a second it displays the corresponding left image. The glasses you wear have shutters in them that constantly open/close in synch with the image, so that while the left image is being shown the right shutter is closed.

Basically they're exploiting persistence of vision -- the images are going fast enough that you don't notice the flicker, and since each eye is seeing an offset image your brain interpolates it into 3D. I've not used it myself but the reviews are pretty good. The downside of course is the glasses aren't cheap (around $150 or something I think) and you need a compatible monitor. You also can't view 3D content at 120Hz -- since half the frames are being used to show the same thing, just offset -- which may or may not be important to you.

I think this is the same sort of solution that companies like Sony and Panasonic are pursuing for their home theater 3D products.

As for the monitors that work without glasses (the term of art here is "autostereoscopic"), there are a few ways of doing them. They all do basically the same thing, which is to use half the pixels in the monitor to display one image, and the other half to display the other. The two images are interlaced, so that one row/column of pixels displays the right image, and the next displays the left image, and so on.

They then have some sort of lens or barrier on the screen that prevents the light from each row/column of pixels from leaving at a certain angle. The net effect is, that if you stand in the right spot, the light from the "left" pixels only reaches the left eye and the same for the right.

The downside is that because light waves expand outward and interfere with each other, there are a limited number of viewing zones where you can see the 3D effect. Move too close or too far off center and you don't get it. Clever engineering can net you a few different viewing zones, but this is a limitation you have to deal with.

It also means that you only get half the resolution that the display offers, since the "single" image you're seeing is really two images interlaced. Phillips had a monitor (recently discontinued) that used this technique, but was some super high definition display. It cost around $20k or something, so you can see why maybe it didn't fly.

As to when you'll see any of this, that's a good question. I think you're more likely to get it on computers with active glasses (gamers are probably willing to do that) before you do on TVs. I think Sony and Panasonic are fighting about how to standardize all this, and it remains to be seen whether people will shell out the dough for active glasses.

The autostereoscopic stuff is cool but again, probably better suited for other applications than home theaters (things like video games once again make the most sense).