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can I make a passive 3d monitor with two identical monitors? Answered

I've got two exactly identical monitors laying around and some passive 3d glasses from the cinema(realD), with these monitors I would like to make a 3d monitor. I think it might be possible but I don't know exactly how so could anyone explain how/if this is possible both by?

ps: If this is even possible I don't want to spend much more than 50 euros to make it. 



Best Answer 6 years ago

It is possible to do it, but you need more stuff. If you put the two monitors at right hangles with one facing you it is possible to superimpose the two images properly. To do that you you use a half silvered mirror at a 45 degree angle. Then in front of each monitor you put a polarizing sheet with the polarization angle horizontal for the face on monitor, and vertical for the sidewase montor. You can then use "special" glasses with vertical and horizontal polarization. If you really want to have circular polarization as used by RealD, put a 1/4 wave retarder at 45 degrees in front of the entire assembly. Some monitors produce polarized light, and this can prevent you from inplementing this scheme.

But there is a simpler arrangement. You can put the monitors either side by side or one above the other. Then buy special "prism" glasses. You can get them for either side by side or above below viewing. The main problem here is that you must keep your head absolutely level. This arrangement will preseve full brightness. A head clamp may be the solution. But then you need to acquire the software to drive the 3d monitors.

Buying a 3D monitor is probably the best solution, and the new LG can sometimes be purchased for under $300. But it does not have full resolution, and I found the ghosting to be excessive, but some people found it acceptable.

You need an optical arrangement to in effect move your eyes further apart. You can make one simply with mirrors and a bit of card. Imagine a periscope on its side. Mount two of them, one for each eye and point then at the two monitors. Put an other piece of card between the monitors so you can only see one monitor with one eye. This will allow you to merge the images into one. I have made on of these and used only one monitor having the two image pairs side by side on the screen. There is no reason why you can't do it with two.

The passive 3D glasses are probably polarized glasses. You would need to first put polarizing filters over the two monitors (or two windows on one monitor) orienting them at right angles to each other and in the same orientations as the glasses, so light from each monitor/window is blocked for one eye and seen only by the other. Depending on how comfortable you are crossing your eyes or going a bit wall-eyed, you might also want some optical components -- like an old 3D photo viewer for the windowed approach, or a half-silvered mirror for the two-monitor approach -- to get the images at least mostly aligned with each other so your brain can then orient your eyes to do the remaining alignment.

Sheets of polarizing filter material aren't very expensive, so I think you should have no trouble doing this for under 50 euros.

But that only deals with the video end of it. You *also* need to produce the two slightly different images that each eye will see. I don't know whether there are any software DVD players which can decode the current 3D DVD standard (which uses alternating frames and active LCD-shutter glasses), or indeed how well/publicly documented that standard is, so that may or may not be practical. But if all you want to do is produce your own computer-rendered 3D images, that's quite possible and I would bet that many of the current rendering tools have a shortcut for doing that already built in... and some of the 3D game engines *may*, which would be neat.

Two monitors would work if you could look at one each with each eye and split the 3D signal, but that ain't going to work in reality.
The spec's are only any good for something that you are actually watching in that format, on the right equipment.


You only need one monitor.

You show two images that are spaced slightly different so that it is interpreted by the brain as 3d. The glasses make each eye see the right image.

So you need to doctor your image instead of add a monitor.

and how exactly will I be able to do that? And where can i buy such a thing that polarises the monitor the right way?

I don't think you can do it that way, you HAVE to have the images pretty well superimposed on a single monitor, because the stereo effect won't happen, or you will get a crippling headache, or possibly, both.