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Thread: Home Built Laser video projector

  1. #1
    Join Date
    Apr 2005
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    36

    Default Home Built Laser video projector

    look for yourself, its incredibly well done:



    http://heim.ifi.uio.no/~haakoh/avr/#projector

    it works by having 16 mirrors on the x axis each slightly increasing in tilt on a spining motor and so when it is turned on it basicly draws each point as it gets bounced their by the mirrors and by blanking the laser just right he uses the mirrors to direct the laser on a grid pattern to project little videos

  2. #2
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    Feb 2005
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    Switzerland
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    Very impressive, that's sure... And very simple to do!
    Just the modulation has to be very precise and synchronised with the mirrors...

  3. #3
    Join Date
    Mar 2006
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    Ottawa, Ontario, Canada
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    That's an interesting experiment but requires very high speed scanners to give you a raster Image. Also requires the ability to sense the beginning and end of each scan as reference for sync purposes. Also requires line counting from beginning to end of frame just like TV raster. An Image buffer is required to store the bit pattern required to trigger the AOM.
    Without the above maintaining a stable repeatable Image is difficult.
    NEOS made a raster video projector using 2 AOBD ( acousto optic beam deflectors ) but low resolution.
    Another development involving NEOS was 3D imagery using high speed scanners for single color only.

    Checkout this cool application using high power IR laser to Ionize the air and create 3D Images floating in mid air.
    " http://www.newscientist.com/channel/...ch/dn8778.html "
    Profile Redacted by Admin @ 04.24.2010

  4. #4
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    SoCal
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    Well I say, that takes the cake! I always wondered what the difficulty of inducing ball plasma in standard atmosphere was, and now I know...

    That article is awesome! using it for advertising sucks, but if it means I can get
    a hold of one of those babies and design video games which play in the
    atmosphere, then I'm all for it!

  5. #5
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    Norway
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    Topic: Yes that is cool , have seen that before and it`s a killer


    off topi:

    DAMN do they produce 3D images in the AIR now ??

    STOP the world this is going waaay to fast....

  6. #6
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    Jun 2005
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    SoCal
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    More info on that 3D thing...

    http://www.aist.go.jp/aist_e/latest_.../20060210.html



    The beam profile indicates that that's one scary laser they've got...
    since I'd assume they're using big di-electric mirrors w/ 100W capacity

  7. #7
    Join Date
    Feb 2006
    Location
    France
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    8

    Default

    Hello,
    We can also found real laser projector as like as video projector.
    The interest is to have nice contrast ratio for an enormous projection screen.
    (the normal projector can't have enough contrast for very big pictures)

    we can found many information about laser projector :
    http://www.mitsi.com/Projects/Alp.htm
    http://www.laservideo.com/index.html

    I have other links but i can put the hand on them :? so ...

    I don't know a lot about these systems but i think it is an polygonal mirror (like laser printer) for X axe scan and a classical galvanometer for Y axe.
    the two major problems are synchro and laser blanking i think because they must be very fast.

    an other problem is laser power because i think a lot power is required for keep good contrast. (the links i have seen said around 5W of white power)
    looks with your lasers projectors ! if you do raster pictures the luminosity go down. (exept if you have few watts systems but it's not my case )

    Edit : Sorry for my bad english, it's not my first language

    PitchouN

  8. #8
    Join Date
    Mar 2006
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    Ottawa, Ontario, Canada
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    I would venture to guess that the IR pulsed laser being used in that experimental 3D projection into atmosphere is likely a high power ND-YAG say 100 watts CW and a high speed Q-Switch ,say 50 kHz to provide nanosecond pulses capable of Ionizing the molecues in the atmosphere.
    The same type of laser and techniques are used to create images within lead crystals. Micro focused energy creates micro fractures in the crystal latice.

    The first experiments I heard to Ionize the atmosphere were using high power UV lasers to create a discharge path for dangerous storm clouds that are a hazard in Japan . Start fires at refineries, cause power blackouts when lightning hits the sky wire and CT's signal a power corridor shutdown and reroute.
    Also heard of ionizing the atmosphere as a conduit to disable vehicles at a distance, potential military weapon.

    Rick
    Rick
    Profile Redacted by Admin @ 04.24.2010

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