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Femto Fairy Lights - Touchable Holograms (i-programmer.info)

Posted by samzenpus on from the in-real-life dept.

mikejuk writes with this story about a Japanese team working on creating touchable holograms. I Programmer reports: "One method of creating a volumetric, i.e. true 3D, display, is to use a high power laser and focus it on a small spot in space. The air in that spot will be heated to the point where it ionizes and glows with a bright blue light. Scan the laser really fast and you can make a full 3D arrangement of glowing points of light — not exactly a hologram but as good as. Of course, the big problem is that you have a lot of energy being focused on small areas and human interaction could be a problem. You might well get burned by the laser if you attempted to touch or interact with the display. The solution is to use a really fast laser, a femtosecond laser, that heats a small spot to a high temperature but only for a very short time. This is much safer because the total energy involved is smaller. This is the reason you can touch sparks without getting burned."

4 of 57 comments (clear)

  1. The smell. by Anonymous Coward · · Score: 3, Interesting

    I love waking up to the smell of ozone. I'm sure others share my sentiments.

    I saw tech like this ionizing the atmosphere to create holograms years ago. Have they improved on it? Sure, but I can't see it being anything but a diversion from looking for a better path. Even those pools of liquid that use wave forms to create shapes would be better than this. The only thing I can see a use for this tech, of rapid tracking lasers that ionize things, would be in things like a laser defense system, and it could lower the energy cost for such a thing.

    1. Re:The smell. by jeffb+(2.718) · · Score: 3, Interesting

      Well, see, that's exactly what I want. A small (patio-scale) laser defense system, to protect my family from disease-bearing mosquitoes and aggressive stinging insects. If you've got the tech to track targets at that scale of size and velocity, distinguishing desirable from undesirable insects is probably not too tough. I've already seen some demos.

      Would I spend a million bucks on such a system? Of course not. A thousand? I wouldn't, but many would. A hundred? Sure. Come on, exponential advancement!

  2. One question by DarkOx · · Score: 3, Funny

    Will it be possible to mount these things on a shark?

    --
    Repeal the 17th Amendment TODAY! Also Please Read http://www.gnu.org/philosophy/right-to-read.html
  3. Burnt or blinded? by burtosis · · Score: 4, Insightful

    It's not easy to burn humans, skin is usually covered by a film of moisture and skin is composed of mainly water which has a high specific heat.
    Eyes on the other hand are easily blinded by lasers orders of magnitude less energetic that those causing burns. Even reflections from objects can cause temporary or permenant blindness. A technology for hologram displays that blinds it's users is of limited value.