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3D Display a Little Bit Closer to Reality
arielsebbag writes "According to CNET, Several high-tech companies including Sony and Sanyo have officially unveiled a consortium to create technical and safety standards for bringing three-dimensional displays to desktops, laptops and cell phones. They are probably focusing their efforts on the technology developed by Sharp. It looks like they are actually good to go and hopefully the 3D display will hit the market by 2004."
Cad/Cam Medical Research engraving engineering model building mapping weather forecasting physics civil engineering automobile manufacturing shall I go on?
You think that I'm crazy, you should see this guy!
These 3-d displays that they are talking about send two different pictures in different directions. In that ways, you get an illusion of parallax so you see depth.
On a regular moniter, things may be rendered in 3-d, but they are displayed in a flat method. This can be approximated in the real world by closing one eye. With these screens, you get the asme 3-d illusion that you get in a "magic eye", where your brain interprets slight differences in pictures between you two eyes as depth.
The problems mentioned, such as the fact that it does not know where your eyes are to send the right images to the right places, are being worked on, but eye tracking makes the system much more complicated.
There are other, more fundemental problems with screens. Among them are that the focus plain is still on the screen, eevn while the sterio says that the image is somewhere else. This can give people headaches.
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I work at that MIT media lab Spacial Imaging Group, who were mentioned previously on slashdot They have a holographic video which in theory works, It has many other problems, including that the person who built it has graduated and moved on. But in theory, that would be the ideal solution.
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No, no, I'm afraid it doesn't.
Ever watch a 3d-movie. The kind you need special glasses to wear. Like a 3D IMAX or some such movie. Or even the red/blue lenses kind. That's what they are talking about.
Two different images are projected, one for each eye. This gives the illusion of parallax. You are tricked in to thinking the image is 3d because each eye receives a slightly different image.
And, just as with a 3d movie, changing your viewpoint doesn't let you see the side of anything. It will simply make the illusion start sucking as you need to be in the middle for it to work perfectly.
Justin Dubs
Seen 3D displays already from 15" LCDs to 50" plasmas from ddd. Check them out at www.ddd.com
This has actually been done, but using specially created crystals instead of a gas. Somehow when the two lasers hit the same point it causes the crystal to fluoresce. Unfortunately the process to create the crystals is extremely expensive and they were having a lot of trouble with the scan rates of the laser, iirc.
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Here's a (apparently outdated) link:
http://www.vdivde-it.de/felix/english_solidfelix.
Search first, ask questions later.
No. That was precisely my point. A hologram is a real effect to the point that it has focal planes. In an analog hologram, every piece of information about a light wave, including its direcion and intensity, is saved in a diffraction pattern, that can be read by shining the reference beam again. In a holographic video system, something is causing the exact same diffraction patterns that the holographic plate would have stored.
The beam is never focused anywhere. It is brought back when the hologram is viewed. The loss of focus planes would come from projecting a focused image on a screen, the first place that happens is your eye. You can focus on the front of a hologram, and the back is out of focus, or visa versa. At my lab they have printed some holograms and messed up the focal planes so they just looked wrong.
http://www.realtime-3d.com
there are graphic @dult 3d videos and images availabe that display the possiblities.
There are two components to how people use the focus cue for depth perception. There is the blur gradient, that is how things in front of and behind your point of focus get blurier. There is also your eye muscles physical accommodation to this depth. Research seems to indicate that the blur gradient is not as important as the eye's accomodative depth. The depth of focus is a really hard thing to simulate on a display. You can try to use a measure of gaze direction, but to stop people from getting uncomfortable the lag needs to be reduced to almost zero. So you effectively need many depth planes you can project onto.
As for holographic displays, one of the problems with them, or any volumetric display, is that there is no occlusion in the scene. This really limits the quality and usefulness of this method.
I don't have to imagine, I've seen it. About 10 years ago at a TV exhibition in Tokyo, NHK (IIRC) had a demo of 3D HDTV - using glasses, 1920 line projection display in a pretty good quality viewing theatre. They had two films. The first was standard chocolate-box pretty pictures - brightly clad children playing, flowers, pretty girls dancing etc. Then, with very little warning, they switched to an experimental project on brain surgery, designed to let many surgeons see inside a minimal sugical incision. We we suddenly looking at a hole in someone's head, projected 6 feet wide in 3D. It was not fun - but it did show a serious advantage to 3D displays.
Consciousness is an illusion caused by an excess of self consciousness.