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Mixed-Reality 3D Volumetric Projector 112

First time accepted submitter Gortu writes "We are describing and demonstrating a 3D Volumetric Projector (YouTube video); in short words: a device that enables mixed reality. The 3D projector has very poor quality, we just have 10 rotational voxels (as we are using only 10 regular LCD projectors), but is proof of concept for developing a commercial solution."
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Mixed-Reality 3D Volumetric Projector

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  • Yawn (Score:4, Insightful)

    by Anonymous Coward on Sunday November 06, 2011 @06:40PM (#37968716)

    10 projectors and smoke... quick someone give them a patent.. lol

  • by LikwidCirkel ( 1542097 ) on Sunday November 06, 2011 @06:47PM (#37968760)
    Similar things have been done with lasers for years. It's not really a new idea.. This guy just uses LCDs instead, which don't even seem to work as well. Watch the opening ceremonies of the Olympics in Athens from a few years ago for some pretty decent 3D projections in space.
    • A matter of flexibility. Lasers can't do complex shapes very well, while LCDs could. The downside is that you need a *lot* of LCDs. He doesn't have enough, but estimates that a hundred would be needed for a clear image - and keeping a hundred projectors in perfect alignment is quite a challenge in itsself.
      • by Anonymous Coward

        A laser can give out phase, which results in spatial cancellation of multiple (synchronous) rays. An LCD cannot. Don't see what this guy tries to achieve here...

      • Lasers can't do complex shapes very well..."

        Casio ( and Microvision ( are both going to be pissed when they find this out, considering that they both have had laser powered projectors on the market for some time now. Just imagine their faces when they find out after all the years of research and development and even several years on the market that their projectors really don't work. I think it should be a crime for someone to change the rules of physics after someone has successfully

  • []

    The smoke-and-projectors system looks like a nice prototype, but it's a long way from practical. Needs more projectors, and some way to maintain uniform fog distribution in a room.
    • by Dwonis ( 52652 ) *

      Needs ... some way to maintain uniform fog distribution in a room.

      Or a way to measure the fog distribution in real time and adjust accordingly.

      • Re: (Score:3, Insightful)

        by optimism ( 2183618 )

        Needs ... some way to maintain uniform fog distribution in a room.

        Or a way to measure the fog distribution in real time and adjust accordingly.

        Or a way to redundantly re-state the quoted post.

        • Or no annoying, eye watering fog at all. Jusy sayin.

        • by Anonymous Coward

          I think he meant, adjust the brightness/darkness of the projection to compensate for the reality of the fog at that moment...

          not redundant at all, actually an entirely different, and potentially extremely interesting, idea...

      • For this, Heisenberg compensators [] work just fine, thank you.
    • Re:More impressive: (Score:5, Interesting)

      by jimshatt ( 1002452 ) on Sunday November 06, 2011 @07:36PM (#37969056)
      Impressive, using a rotating mirror: []
      • by Gortu ( 523033 )
        But not immersive, I wouldn't want to be nearby that 6000 RPM rotating mirror :-).
        • No, the hologram immerses you! Must be a Sovjet Russian invention...
        • But not immersive, I wouldn't want to be nearby that 6000 RPM rotating mirror :-)

          Actually, from the stats displayed 0:26 into the video: Spin rate 15-20 Hz. I think that can be done safely, especially if you enclose it in a clear co-rotating cylinder to avoid air resistance.

        • The video mentions 15-20 Hz. That is 900-1200 RPM: still impressive, but not connecting-rod-throwing impressive.

    • by EdZ ( 755139 )
      Not 3D. Look closely: while it has 'depth', the depth resolution is 1: it's a 'thick' 2D display.
    • by Ksevio ( 865461 )
      He should be using a machine to generate haze, not fog. It's been used in shows for decades to make cool lighting effects without needing to jump around with a fog machine.
    • "and some way to maintain uniform fog distribution in a room."

        I know some college buddies who have actually figured out how to do this- completely inadvertantly mind you. The fog itself in their case also has the added effect of neuromodulation-making a room full of people actually impressed (if not downright giddy) about 10 projectors sitting on the floor showing a cruddy light show.

    • Think I prefer this: []

      No smoke (that I can see) and no glass aquarium
      • Cool as that is, I can't see how it works - it appears to defy the laws of physics as I know them. This means either the designers have found something so clever I can't work it out, or the video is fake. If it works, it could render pole dancers obsolete.
  • If by several he means everything..yeah.. that's a good point. I can't believe I just sat through that.

  • As a proof of concept, it works better than I thought it would for such a small number of projectors (probably why everyone who's already had the exact same idea has dismissed it without trying it). Using many more, dimmer, projectors (a bunch of those always-in-focus pocket laser projectors would be perfect) would minimise the brightness of the ghost beams and spread them over a wider area.
    • by Gortu ( 523033 )
      You are right on track. 100 projectors is the minimum number of projectors that make individual rays so dim as to make them invisible, so you only see the projected volume. You'd need 500 projectors, to get good rotational resolution.
  • by TheCouchPotatoFamine ( 628797 ) on Sunday November 06, 2011 @07:12PM (#37968924)

    My best idea is to use a hundred pulsed water guns and a laser that can be precisely aimed on the fly. You emit downward-dropped, fast-moving squirts of water algorithmically timed so that when the drop reaches the "pixel" the laser also illuminates that spot, making a pixel appear in midair. If the guns are in a row, that's a 2D plane. You could do this with a 100x100 water guns to make a 3d system, where 2d is the box of water guns on the ceiling, and 3D is when the drop is illuminated.

    Make sense? I so want to do this!

    Every CS major knows the time/space tradeoff. Those majors never get taught the third tradeoff of the set: comprehension

    • by vadim_t ( 324782 )

      Like this []?

      It's very cool but seems impractical. Noisy, lots of water needed, and I think color is going to be tricky, as how are you going to reach a drop that's enclosed in different colored drops?

      • by kkwst2 ( 992504 )

        While cool, it is really note that close to what the GP is proposing. This is essentially just a defined pattern of water going through a sheet of light to make a pattern.

        The GP is proposing a complex combination of water pattern with lasers to illuminate it to create a 3D image.

      • If each drop emitter also has a laser emitter pointing down along the path of the drip, then you can individually illuminate each column of pixels. although, i think i like the term drixel for dripped pixel. Then you still have the problem of you can only illuminate one drixel in a column at a time, and your have a refresh rate that's tied to the acceleration of gravity. Also wind would screw this up, but as an art project it would likely be pretty cool.
        • The math isn't even that hard once you realize how DLP works. DLP plus a huge version of an inkjet printer nozzle.

    • Disney does something similar with World of Color []. They have expensive cameras that project movies onto the streams of water. It's not as precise as your setup intends to be, but it's still impressive.
    • by Hadlock ( 143607 )

      You wouldn't need an aimable laser, you could just use a DLP projector. The main problem I can see with the system is that you would have a tremendous amount of input lag for the bottom half of the display until you could write an algorithm to predict where you can place water droplets early so they wouldn't obstruct view, but would probably be used/lit towards the bottom of the screen. You'd probably just need an engine that could keep track of a 100x100 grid and which items on the grid you could light up

    • I think that's a great idea.

      Some problems:
      * Since water is transparent, voxels closer to you won't block ones farther from you. Everything will be translucent.
      * Reflections and refractions will cause unintended lighting.
      * Drop size and timing precision will limit resolution.

      A few thoughts to make it work well:
      * The drops will take a while to fall. For playback this is fine, but for realtime use you'd need to release drops in case they might be needed. Thus you need a gener

    • That's a really cool idea..
      I just saw this video the other day where they use a device to deliver precisely timed drops of water which could be used for that. []
      The lasers could be positioned so any drop could be illuminated at any time without being obscured by other drops. You might have to have a laser scanner between every other row, or use mirrors to direct the laser to the row to be illuminated. I don't know if mirrors are fast enough
  • High quality 3D (Score:4, Interesting)

    by TuringTest ( 533084 ) on Sunday November 06, 2011 @07:19PM (#37968960) Journal

    This approach by Sony shows much more promise in the short and medium term: []

    No walking through the image, though.

    • Re:High quality 3D (Score:5, Insightful)

      by EdZ ( 755139 ) on Sunday November 06, 2011 @08:08PM (#37969290)
      And only in one plane. Move up and down, and the image will distort rather than allow you to look down onto it or up under it. Not volumetric.
  • Not slashdot worthy (Score:2, Informative)

    by castrox ( 630511 )

    This video is lame. What did these guys accomplish? It is kind of hard to tell. 10 projectors + smoke. A guy claims there is a sphere -- well I do not see it. Now he says he is walking inside the sphere. Still do not see it.

    What the hell is this?

    • by Fnord666 ( 889225 ) on Sunday November 06, 2011 @08:35PM (#37969444) Journal

      What the hell is this?

      it's a pitch to try and score some funding.

      We need funding and are looking for people interested in participating in this. If you know someone, shoot!

    • by ddt ( 14627 )

      What the hell is this?

      I think that smoke is the kind you're supposed to be careful about inhaling.

    • The end of the video (in case you stopped watching partway through) gives some random philosophical musings as well.

      Finally, we'd like to discuss as to why we are opening this up. The answer is actually very simple--because we have the power to do so. The world is not in a good shape and we believe there is a problem of power. There is imbalance with giving and receiving. We would like to add our two cents by showing things can be done different--that there is a way of giving things that benefits both the giver and receiver. That's why we're offering our consulting services to anybody who is interested in pursuing this endeavor. We also opened a blog at where we will be posting news related to this project.

      Finally, a philosophical note. Never forget: you have power. And the enemy of this power of yours is fear. That's why we are constantly bombarded with bad news. That's why accepting things you don't like is giving away your power. We believe it is a good time to change things in the world, and we know you can be part of that. Also, do not use your power in an evil way. You can be assured evil things will come out. Use your power with goodness, and we'll live in a world where our grandchildren will be happy to live in.

      So, we hope that this project will crystalize soon, and that all the changes that are happening in the world will not lead to an evil outcome. You can be part of a good change. Don't forget.

      Personally, while I wish them luck in their endeavor, I also find their proof of concept very lame, and these philosophical musings ramble around some potentially decent points, but are out of place. They can sort of project very basic geometric shapes, if you're willing to put up with lots of smoke and very poor resolution, with poor color. It's not ready even for a YouTube preview, let alone

  • While this HAS been done before for decades w/ "lasers" & the narrarator wasted too much time w/ obvious philosophies, the off-the-shelf projector use IS intriguing & it's nice to see someone finally implement it freely. Still, brightness/contrast is shit, light-bleeding is a BIG problem & the whole setup is useless w/o a fog machine. I'd still love to see a high-resolution color setup though...
  • I think I saw this at a laser show in 1990. Using a projector instead of a laser isn't really that interesting.
  • ... and a lot of smoke.
  • Ok, interesting idea.

    One way to make it better would be to use eye trackers. Then the image from each projector would mask out a small area around each users eyes. if you're going to have an installation using hundreds if not thousands of projectors, the expense of tracking the eyes in 3D space and calculating the appropriate mask for each projector shouldn't be too great. If you don't have the precision and time responsiveness necessary, just mask out the entire face using commercially available face r

  • Smoke and mirrors.....and flashlights. Cool, man.
  • Well, I for one welcome our new smoke filled virtual future.

    But seriously, that was the assiest demo I have ever seen. Are they kidding? Maybe it's a viral ad attempt.

  • Smoke + a few projectors? Wasn't this done in something like the 50's? I like this approach more: [] Basically, they use lasers to excite atoms in the air in the room, creating small glowing plasma balls as pixels. Not by far ready for any commercial use (seems to be able to "draw" someting like 20 pixels per second), but at least it's "true" 3D projected in mid-air without smoke or mirrors.
    • by Gortu ( 523033 )
      But it's not immersive, you can't go in there. And you can't project colored objects.
    • by macshit ( 157376 )
      Hmm, neat idea, but my god, the g4tv presenter / production are mega annoying... I was wishing there'd be some sort of laser control malfunction and her head would explode... now that'd be youtube worthy!
  • Never thought they could image a Steampunk version of Prof. Lunazzi's 3D screen - []
    Wait...using vapour and one LCD projector per voxel is "serious" not Steam age retro joke? What???

  • Seriously, the local planetarium used to put on laser shows with fog machines and way cooler effects than this, they worked on the same principal. Not to mention the music was a lot better.

    Pretty lame.

  • by Crudely_Indecent ( 739699 ) on Sunday November 06, 2011 @10:37PM (#37970006) Journal

    Well, not so hidden - it was spoken at the end of the video:

    "A philosophical note: Never forget, you have power, and the enemy of this power of yours is fear. That's why we are constantly bombarded with bad news. That's why accepting things you don't like is giving away your power...."

    I think this is a great philosophy. How often do you watch the news and everything is gloom, doom, collapse, corruption.... Rarely do we hear about the good things people do.

  • Okay, while this was kinda cool, like most people have been mentioning, nothing new really... To be honest when I read the title I thought it was some sort of advancement of this caliber: []
  • this brings up something i think nvidia could do with their 3d vision glasses. they should intergrate infrared leds in the sides of their 3d glasses, and package a webcam with them, so they can do a johnny lee style headtracking thing, as demonstrated in this video []. nvidias 3d vision already makes starcraft 2 look like your looking at a table with 3d minatures on it. the only thing missing from it to make it look like a fully fledged 3d object sitting behind your screen is the ability to move your head arou
  • fVisiOn light field projector demo, using animated Hatsune Miku. Check out the part where the mirror is placed behind her: []

    • by Gortu ( 523033 )
      Again, a rotating mirror at 6000 RPM is something I wouldn't like to have close to me. Also, you are limited to a plane from which you observer the illusion, what we do is fully 3D.
      • by Guppy ( 12314 )

        Again, a rotating mirror at 6000 RPM

        There is no rotating mirror, this particular display technique uses a completely different operating principle. The image appears floating above a flat surface, which you can put your hand on. In some of the posted videos, the presenter takes off the cover, showing the projector array beneath.

  • title says it all.

  • No technical innovation, of any significance, in demonstrated in the YouTube video above. I look forward to 3D volumetric displays but I won't be looking in their direction.

UNIX is many things to many people, but it's never been everything to anybody.