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Holographic projector

  1. Feb 25, 2010 #1
    Greetings to all. In my first post, I'll present an idea based on acoustical holography.

    I intend to design a Holographic projector using sound and laser. The hologram is created by reflecting reference laser light on a vibrating diaphragm matrix. The diaphragms are vibrated by means of piezoelectric material or quartz like material. Every diaphragm projects a piece of a 3D image in a specific space, therefore, for a 1m^3 image for example, 1000 diaphragms make the matrix, each projecting a 10X10X10cm hologram.

    My biggest problem in this system is: The reflective material to use, the ultrasonic oscillator and the reference laser's power/frequency/color(s) in order to make the hologram visible.
    (or maybe if that system is even possible to build).

  2. jcsd
  3. Feb 25, 2010 #2
    Lol, this is old stuff, as the MIT media lab have already introduced such a device called the "Mark-4". This thing, like your idea, has a crystal of lithium niobate sandwitched between two piezoelectric transducers. These transducers vibrate in the ultrasonic. They cause the crystal to modulate three lasers as they are passed thru the postage stamp-sized crystal (one R, one G and one B laser for a color display). The modulated laser light then passes thru two HOE's (google it), then falls on a piece of glass with a coating of fine-grained bi-refringent crystals on one side.
    The result is a color 3-D moving image. Here's the source:
    Last edited by a moderator: Apr 24, 2017
  4. Feb 26, 2010 #3
    I see... Thank you for replying! However, you seem to have misunderstood my concept (maybe not...). The idea is not exactly same as the one mentioned above. The principle is basically the same, is more like generating micro holograms to make one image. The other difference is the display medium. I prefer the hologram to be projected from the projector, to be immediately visible by the naked eye (or by using special glasses) from 360º angle. This might be accomplished by the use a fourth matrix- for spacial distribution of the holograms- projecting HOE's. I could also use the same principle to generate Holographic sound.
    I didn't say I'm inventing a projector, but designing...
    I know lasers have been around for decades and people went crazy about them in the 70's. We don't have 360º imagery in our homes today, coz PC's are incapable of computing high quality holograms.
  5. Mar 13, 2010 #4
    Multi-polar waves...

    Actually one powerful way to produce holographic effects is to make electromagnetic waves that have different polarity arrangements called multi-polar waves:
    With this technology new audio-visual and other holographic effects can be obtained.

    Attached Files:

  6. Mar 15, 2010 #5
    Thanks for the info! Any tip on spacial holography is good for me. I'm just not very confortable to expose humans to EM fields for long hours...
    The Holographic projector has to be user friendly, meaning safe. Although EM fields have sterilizing effects, it might prove unsafe to be exposed to it too many hours (is like being on the cellphone the time I spend on the PC.
    I'm aiming at full immersion, where the image melds with the user surrounds. To illustrate it, imagine playing an adventure game and then you equip an armor. That armor has to appear around the user.... That's why ultrasounds seem pretty much viable to me.
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