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Hi,
Curiosity has the better of me and i'm wondering whether it is possible to focus a laser over several meters such that it can still be useful?
We've all seen these cnc cutters which work at close range but is is possible to do this over, say 30m, and still cut? As far as I know this isn't already done so I was thinking is it actually possible.
What do you think?
Do you*really* want a 30m beam path with your dangerous cnc laser.....?
Quote:
Originally Posted by Michelle
You'd need a very stiff jig to hold the point still enough too. Forget hand helds if that where this is going...
Quote:
Originally Posted by Michelle
I think that goes from industrial tool to industrial weapon... good luck though. *retardo
The biggest problem I can see would be the usefulness of such a set-up.
The smallest quaver in the emitter would translate into several centimetres/inches of drift at the focal point.
However ifyou were take the device into space removing the atmospheric interference and gravity issues a gyroscopic stabilized high powered multi-head device might prove very useful for working on "nearby" objects.
A few computer controlled mirrors could manipulate the beam(s) to converge on the point of interest magnifying the abilities of the device as well.
So I gotta know, what prompted you to ask ?
The reason no one does it is cost. You need a very high quality beam to begin with, and you then need to expand and scan that. 30 centimeter scanning mirrors and 20 centimeter telescopes are not inexpensive.
Steve
" 15 characters"
The only reason I ask is pure idle curiosity. I saw an article on the bbc news a few months back (can't find the link at the moment) about using lasers for defence purposes against pirates etc and this got me thinking...how do they do that. Basically it was a ship based laser the navy used to deter pirates at sea; clearly they didn't go into much detail. It is not the sort of thing you hear about every day is it? :DQuote:
Originally Posted by ShortyInCanada
Interesting concept I suppose for world supremacy; he who controls the skies!! If these conspiracy theorists are right, some government already has lasers in space that can light a fag down here on earth or blow missiles out of the sky. I don't fancy it lighting mine especially with it in my mouth :eek:Quote:
Originally Posted by allthatwhichis
Is that what you would need, a 30cm mirror????
There was also a youtube video where these guys put a green laser through what looked like a telescope and could light a match at 300ft. What I want to know is why didn't it try to burn anything in the background but it did a match??? How much power would be left in it at that range?
Ah yes, it believe those are chemical lasers, which are a bit different than the gas and solid state lasers generally used on this forum!Quote:
Originally Posted by Michelle
They get up to the megawatts (according to wiki). perhaps it's by sheer power they can still damage things at range.
Craig
At this time the best use for a laser against pirates is to blind them while boarding parties approach or as a designator for a high tech weapon.
The problems for Navy ships with rolling seas, sea spray, mist/fog, the absorption levels for different materials/colors, and a whole host of other factors have proven to be very detrimental to laser usage at sea. But there are other programs and types of lasers that are still being tried out.(see the thread about FEL posted here at PL)
About your comments ; "put a green laser through what looked like a telescope and could light a match at 300ft. What I want to know is why didn't it try to burn anything in the background but it did a match???"
I bet that the only place they could light the match was at the focal point around 300ft away. Then the beam starts to spread out again and loses it's power.(technically it just spreads the power out over more surface area reducing the exposure per cm.) If they did it right the optics should correct the beam parametres so that the beam travels perfectly straight and neither expands nor contracts in width over distance. Then the beam would go on forever. But you wouldn't be able to do that with just a telescope ! And lighting a match at 1 ft. would also work at 1000 ft. Just doesn't happen I'm afraid.
LW : "I have seen what a 3kW Mitsubishi Co2 can do to a garbage can and a wall from across a parking lot." - Pictures ???! Pleeeease ?