Polarized light+TV

[Molten]

Does anyone know if you can send polarized light through a tv? I've got an idea that would require that ability and I wasn't sure if it was a waste of thought.

[Al Skierkiewicz]

In a manner of speaking, yes. The effects are complicated by the horizontal and vertical scaning and the alignment of the phosphors/pixels/LEDs in the display. If you desire to transmit an encoded stereo-optic image and wear polarized lenses at the receiver, you will have some success. If you wish to put a polarizing filter in front of the camera for a visual effect, you will have varied results.

[Molten]

Ok, why I ask is that I had an idea to have a video game where you have two people playing at the same time on the same screen and not see the other players action. Sort of like when you choose a play in football. You don't want the other person to know what you picked. My thought is have the top half horizontal and the bottom half vertical and have each player wearing glasses. That way each can see their half. Think it would work?

[tseres]

it works fine when i try it with my mom's polarized sunglasses

[Al Skierkiewicz]

I don't think that would work very well as the cross talk between two screens would be evident. Combining computer generated graphics with polarization generated electronically is also a big stumbling block. I have not heard of anyone performing electronic polarization although it might be possible. A cheaper alternative at the moment would be two sets of goggles. If the individuals are playing the same game, you could conceivably display a background on a common display while feeding separate overlays to the individual goggles.

[Molten]

True, however those goggles would be fairly expensive and would need to be bought for speccific games. If you could program the polarized light onto the disc, you could in turn make the glasses as cheap as some of the 3d glasses you get off of a cereal box. Granted that our current technology is a good leap from that point, it was just an idea I was wondering of its possible future applications. From your responses, should I assume that this is not going to be the future of gaming?

[whytheheckme]

I'm not too sure that I'm allowed to say too much about this but....

Last time I was in nVidia's private demo room (we have an awesome relationship; I get tours of their new technology (2, 3 + years ahead)), they sat me down on a sofa, and handed me a pair of polarized glasses. They booted up a machine attached to a 60" (LCD I'd presume) display, and showed me some video games. They said that it was simply software running in the background, and wasn't game specific (using some type of technology to pick out distances, I suppose.) What I saw was a completley 3-D gaming experience. The HUD in a game was closest to me, with objects getting farther and farther away, to the point of the screen and even further.

So in short, YES, I have seen this work. I hope I haven't violated any rules by talking about this (if you work at ATI, please, pretend you didn't just read that )

I got to keep the cool nVidia polarized glasses for free! (Cardboard with clear polarized lenses in them.

-Jacob

EDIT: I lied. (I took that tour about a year ago.) They apparently have the software out for release to the public ( http://www.nvidia.com/object/3d_stereo.html ). In this version, apparently, red/blue glasses are required.

EDIT2: It appears that this driver is currently compatable with the following:

Supporting Displays

* Passive polarized stereo displays
o Zalman Trimon ZM-M220W (22 inch 1680x1050)
o Zalman TriMon ZM-M190 (19 inch 1280x1024)
o Zalman HDTV LCD (1366x768)
* Anaglyph display with red/blue stereo glasses

So, for someone more experienced than me, does this mean that you could use a regular TV with red/blue stereo glasses, or use one of the Zalman TVs with polarized glasses?

[Molten]

It figures, I always come up with an idea after it was already invented.

[usbcd36]

NASA Glenn has a lab where they have created a simple virtual-reality world using four 120 Hz CRT projectors and LCD shutter glasses. I was in some programs there, and got to meet the guy who puts this stuff together. There was also a remote with a three-axis accelerometer that could be used to interact with the game. This setup has been around for awhile, and I remember thinking about it when the Wii came out, because the user interface was very similar.

FYI, LCD shutter glasses are glasses with two LCDs as lenses, which are basically one pixel each. They receive a binary signal from an IR emitter connected to the computer or video source, which determines which lens is black and which one is clear.

Anyway, you could use LCD shutter glasses with a 120 Hz TV nowadays (the HD transition is causing them to become more common, especially because they enhance the picture quality of 24 fps movies) and use the same principle the glasses use, only instead of one lens darkening in each pair of glasses, both lenses in one pair would darken, then both lenses in the other pair would darken.

The problem with this situation is that you're only getting a 60 Hz refresh rate with darkness between, so the video quality suffers. Furthermore, you've gone to the trouble of developing a system that has everything present to enable the use of stereo gaming, but can't be used for it because head tracking only works for one person at a time, and dividing the refresh rate by the number of lenses (in this case, four) results in an unacceptably short amount of time for which the picture is displayed, followed by an unacceptably long amount of time when you're seeing nothing.

[Al Skierkiewicz]

Originally Posted by usbcd36

Anyway, you could use LCD shutter glasses with a 120 Hz TV nowadays (the HD transition is causing them to become more common, especially because they enhance the picture quality of 24 fps movies)

This technology is called "line doubling" and is a technique to make standard def appear more hi def. It is also used to interpolate an interlaced video source to display on a progressive scan monitor. In projection systems, this technique also gives a brighter output by doubling the amount of scan lines displayed at any one point in time. Remember that HD or DTV signals use 60 Hz frame rate max. Anything more than that is generated in the display.

[mrbob1000]

you can have cyan glasses and red glasses and then have both players on the whole screen. red player wouldnt be able to see blue players screen because its red (so red player has a blue screen and blue player has a red screen) then everyone sees violet!