Naked Science Forum

Non Life Sciences => Technology => Topic started by: MrYman on 03/03/2012 18:37:01

Title: Can a picture be created in fog with a laser?
Post by: MrYman on 03/03/2012 18:37:01
What happens if two laser beams meet in a fog? (Imagine a very fine fog, human made, almost invisible to human eye.)

Would the meeting point be more visible? Due to interference...

If so, then it would be possible to draw a 2D picture if lasers would move fast enough to trick human eye/mind into seing a complete picture?

And stacking many lasers in layers it could be possible to 'draw' a 3D image? Thus creating a hologram?
Title: Re: Picture with lasers and fog...
Post by: MrYman on 04/03/2012 21:07:33
Is this in a wrong forum or just boring question/idea?
Title: Re: Picture with lasers and fog...
Post by: graham.d on 04/03/2012 21:52:48
The fog particles would certainly scatter the light from the laser and the particle would then be more visible but I don't see how to avoid the laser hitting other particles on the way to the one you want to illuminate. I understand that what is wanted is a sort of coordinate (X/Y/Z) selection of the particle to be illuminated but I can't see a way to make this work and don't see how interference effects would help.

It would not be a hologram which is a very specific way of producing a virtual 3D image from information stored on a 2D surface.

I have seen such concepts used is SciFi movies but, then, they don't have to reflect reality.
Title: Re: Picture with lasers and fog...
Post by: graham.d on 04/03/2012 22:03:04
Come to think of it there are some materials that can be made to react to light in a complex way. I suppose if some fine particles could be made such that light from a laser at one incidence were absorbed unless light was also incident from an orthogonal direction when it scattered the light some such system could be devised. I can't say it would be possible but, in any case, not right now. I expect some money could be made if anyone can think of a way though. Then getting the object in colour would be also tricky, not to mention giving the object some solidity rather than being transparent. Another issue would be to do with the dust particles size relative to the wavelength of the incident light.