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Television Media Science

Holographic Television and Optical Transistors 26

Posted by michael from the moving-picture dept.
Radical Rad writes "This is based off an article from the American Chemical Society Journal and says that 3D TV may be less than a decade away due to an advance made at UCLA which allows portions of crystals to be brightened, darkened, and change colors in nanoseconds using electic and magnetic fields. Light passing through the crystals might then be used to project moving holographic images. The same crystalline material could also be used in optical computers and probably many other applications."
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Holographic Television and Optical Transistors More

Holographic Television and Optical Transistors

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  • Unreal tournament:)

    seriously tho- I always thught those plastic bubble-3d games from the 80's kicked ass. Imagine was it would do for a first person shooter:)

  • Projection, but what about camera tech? (Score:3, Interesting)

    by PD ( 9577 ) <slashdotlinux@pdrap.org> on Saturday March 30, 2002 @10:54AM (#3253785) Homepage Journal
    Nice that we can forsee a way to project holographic images, but is there a corresponding idea for recording holographic images? Maybe the old fashioned stereo camera images would need to be processed into a hologram by a computer.
    • (This is also a reply to Snafoo's "It passes the Porn Test" comment)

      Ron Jeremy has said in at least three interviews that he has been filmed twice in real 3D, specifically saying holograms twice, and that he has seen the results in a fancy prototype viewer. So, yes, there is apparantly some way of recording and viewing. If this seems odd to you, then consider that much of early photography was pictures of naked women and other pornographic images.

      All the interviews I've seen with him were in pretty "mainstream" stuff - on the Discovery channels, the Loveline talk radio show, etc. Anybody care to post some URLs or more info?

      --
      Evan

      • then consider that much of early photography was pictures of naked women and other pornographic images


        So all pictures of naked woman are pornographic? The American Heritage Dictionary defines pornography as "Sexually explicit pictures, writing, or other material whose primary purpose is to cause sexual arousal." Surely you agree that it's possible to have pictures of naked women, the purpose of which is not to cause sexual arousal? Just crack open any medical textbook and you'll see what I mean. While you're at it, visit an art gallery once in a while.

        • Yes, Spoobie, that's why I made the distinction. I'm not referring to Aprodite on the Half Shell, I'm referring to naked pictures of women that men bought and kept for sexual gratification. I have shelves of art books full of naked women - while I'm not a big fan of porn, I am a fan of cheesecake and noseart. Not to mention Olivia and Frazetta.

          Yes, there is art that involves the nude human form. But there was quite a bit of early photography that was titilating and pornographic, involving any combination of sexes and animals. I know - I have a pretty decent collection of it. ;) Interesting that bestiality seemed to be more common than warious dildos. Of course, you're also looking at a small remaining representative sample - much pornography was destroyed by relatives after a persons death (the common "page ripped out of a journal" syndrome that historians speak of).

          --
          Evan

    • That is a good question.

      True holographic recording would reqire some major overhauling in the TV studios.

      It is possible to make holograms from sterographic cameras, but you dont get the true 3D that you get in a normal hologram.

      There is definitely a good argument for just using steroscopic vision in the first place. It is much cheaper and it possible now. I was at the SPIE Photincs West conference a few months ago and got to see several sterioscopic vision "TV sets" that were really impressive. About a dozen big names have prototypes already.

      In reference to the parent article it should be noted that sterioscopic vision does not offer the immense data storage possibilities as holograms.

  • Well, it certainly (Score:4, Insightful)

    by Snafoo ( 38566 ) on Saturday March 30, 2002 @11:02AM (#3253812) Homepage
    ...passes the Porn Test (as developed by some fellow Slashdotter whose handle I forget).

    Basically, the Porn Test says that unless a communications technology helps the dissemination of porn, it will fail. The applications of 3DTV to the adult entertainment industry are obvious, so the technology is bound to succeed.HDTV on the other hand (for instance) is much less useful, as most porn-watchers are too (ahem) busy to notice the higher resolution. So hold off with the $ until you see 3DTVs in Future Shop.

    "Junior! Stop trying to fondle the Wonderbra commercial!"
  • Silver halide and DCG holograms have finer resolutions than the Kodak film most people use. I wonder how the crystal compares. It would only need to create television quality.

    Also if the refresh times of the crystal are not fast enough for comfortable viewing, you could do some 3D interlacing. (They do mention color changes in billionths of a second... perhaps they wont run into retensivity problems.)

    Do 3D interlacing formats exist? Thay probably use them at SGI and Pixar... im behind the times.

    One thing to note is that every frame of the 3D image would be a totally separte 2D interference pattern on the holographic plate. You cant just do a 2D interlace directly on the the holographic plate like you do in TV. That means that you will need to scan the 2 demiensional plate rather quickly, or do it in parallel. I would love to see how they implement the electric and magnetic fields to control the crystal.
    • Not a troll, but why would you want to do 3d interlacing? AIUI (as I understand it), normal 2d interlacing was done to work around the limitations of phospher, TV scan rates, and bandwidth. The phospher needed to be scanned at 60 Hz (either there was no long-persistance phosper available so it would flicker, or long-persistance phospher was available and had a ghosting problem), but horizontal scan rates were limited to too few lines at 60 Hz.

      With a new technology, and especially with all the cool stuff we can put into receivers today (full-frame buffers, image enhancement, MPEG decompression), it wouldn't make sense to be bound to a 1941 standard [williamson-labs.com]. (see also) [ieee.org]
    • My thinking is as follows:

      in TV you are sweeping a beem across a 2 demensional screen of phosphors row by row. You can see the image as it is shot to rows on the screen.

      The hologram is different in that you dont get one frame of the 3D image until you have completely constructed an interference pattern on a two demensional holographic plate.

      If you want the frame rate of the holographic image to be 30fps, then you have to create 30 complete 2D interference patterns on the holographic plate per second. You need a fancy holographic plate to pull this off.

      In the 70's when 3D TV was thought to be the Holy Grail of holography people thought about using LCD as the holographic plate, but there were questions as to how successful the liquid crystal would be because of time it takes for the crystals to change thier alignment. So the idea of interlacing came into the picture.

      But if the UCLA boy's fancy chemical has "color changes in billionths of a second" then maybe this whole issue is no longer an issue.

  • This will probably be modded down quite a bit, but I've always been somewhat perplexed by the concept of holographic projection.

    My question is this: On to what would the image be projected? Would there not have to be some kind of screen or bubble on which the image resides?

    Is it possible just to have an image floating in mid air?

    Hope this isn't a waste of bandwidth! ;)

    Cheers,
    B.

    • What I want to know is how this will be much better than regular tv. Say the image depth is three feet. Most TV pictures have camera shots going back many feet. Now I guess this 3d tv will just have much reduced depth or somthing, kind of flattening out everything. It seems that that would confuse the senses.

      Why not just have high-definition OLED goggle tv. That would look a lot better than this 3d tv and it would be much cheaper.

      What really excites me about this is the optical computing potential.
    • "On to what would the image be projected? Would there not have to be some kind of screen or bubble on which the image resides?"

      The type of hologram which would be used here relies on a wide beam of coherant (laser) light passing through a transparent plate which has been altered somehow to create the holographic image. Currently, this plate can be (at least) a photographically exposed glass plate or a special thermoplastic plate. When the laser light passes through the plate, wave interfearance creates an image which changes based on the viewing angle.

      It sounds like scientists have found a way to replace the glass plate with an electronically controlled media. Since the image can be changed electronically, there is the potential to create a moving 3-D image.

      Since you still have to look through the plate, the image would not just float in mid-air.

      I am just remembering the basics from my optics class. Someone with a lot more knowledge please correct my errors!
      • Yes, the image is a "virtual" image -- you would have to look though some sort of screen to see the image -- but it _would_ appear to "float" behind the screen.

        A hologram can be thought of as acting like a time-shifted "window" onto the scene recorded. If a true full-spectrum hologram was created the light you would see from the hologram would be "exactly" as if you were looking through a window at the subject.

        I would think this would work similarly (as stated above), except the different frames would be electronically created in real time. Electronically created colograms are nothing new, but the resolution required is staggering.

        I took my optics class at U. Michigan from one of the "fathers" of holography. He showed us some large holograms created in the former USSR that were truly amazing.

        He also told us that in the former USSR they made "true" 3D movies by recording holograms of different scenes on a several square-meter piece of film, varying the reference beam angle between frames. By then scanning the reference beam through these same angles in the "theater" the audience looking through the film "screen" would see the movie.
    • I'm no expert, but I think of it this way: a holographic plate has certain properties that cause it to emit/transmit/reflect light in the same way as if it had come from a real 3D object. The effect is as though the plate were a window through which you look at the object.

      Presumably they could also make the object appear in front of the plate, with the appropriate manipulations.

      Incidentally, this also explains that curious property of holograms that you can break one in half and get two full holograms. The effect is like looking through two smaller windows instead of one large one: you can still see the whole object behind the window; you just have less parallax.
  • To liquify the brains of the industrialized world.
  • While taking an AP Physics class a few years ago I created a glass plate hologram by about the simplest possible method. I remember from it that if I turned the hologram upside down and pointed a light source in the right direction I could make the object appear to float in air. So, does this mean that a center-of-the-room, projected-in-thin-air hologram is possible? I'm sure some people on Slashdot know plenty more about holograms.

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