What types of 3D TV are there?
There are two main types of 3D technology that are ready for you to use now. Commonly known as 'active' and 'passive', the two types deliver a similar effect, but have massive differences in the production cost, and how it is passed on to you, the consumer.
Active-shutter 3D is going to be the way most people end up seeing 3D in their homes. With this technology, the TV is basically the same as your current one, but with some increased performance to make the 3D look as good as possible. To see 3D, you'll need a special pair of glasses that contain a system that shuts off the light to first one eye, then the other.
While the glasses are blocking light to one eye, the TV is showing an image to the other eye, then the process switches, and the TV shows a separate image, shot at a slightly different angle, to your other eye. This synchronized shuttering basically provides a Full HD video stream for each eye, each very slightly different. Because your brain is translating two separate signals from your eyes all the time, it's fooled into seeing 3D.
The passive system, by contrast, uses a very simple set of glasses. These use circular polarization to provide each of your eyes a different image from the same source. In cinemas, this works because two images are projected on to the screen in quick succession. They appear at a rate of 144Hz through a special filter that adds polarisation, alternating between the left and right eyes, 72Hz for each.
Translating the passive system for home use would produce much more expensive televisions. These would need to have a panel fitted in front of the LCD or plasma panel that alternated in time with the left and right images. LG is using this system in its 3D TV for pubs.