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ArcticMyst Security by Avery

250mw red to white flashes.

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Well, it's more to do with the temperature rather than anything. The lattice idea is a simplification of what's actually going on. It's used to explain why continuous spectrums are generated by materials even though on an atomic scale they can only actually emit certain wavelengths. I'd love to know how it works in a liquid but that's the way I was taught. Presumably it works in a similar way for liquids (such that the emitted wavelengths represent an average heat and so on). On the internet there doesn't actually seem to be any explanation as to what's going on, the closest it gets to is Planck's derivation of black body laws - by treating particles as perfect oscillators. A common theme in physics at this scale but it doesn't help laser lovers who might be talking about it 80 years later. :cool:
 





Kenom

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wow, who knew such a video would create such a scientific discussion. I LOVE IT!!
 

Switch

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Kenom said:
wow, who knew such a video would create such a scientific discussion.  I LOVE IT!!
It' a complex phenomenon that can be mistaken for lots of stuff I guess :D
 
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If you know how to convert red light into white light, I'm all ears. I, We, can make a lot of money out of it.
 

Benm

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bob1122 said:
If you know how to convert red light into white light, I'm all ears. I, We, can make a lot of money out of it.

I guess that depends on how efficient you want that process, and if you have any demands for the white light.

Photocells and white leds will come a long way if you're not that picky ;)
 

diachi

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the 4th one down makes sense, the goggles wont block the IR but the camera can see it , and most of the red is blocked so it shows up as really bright white ...
 

Switch

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diachi said:
the 4th one down makes sense, the goggles wont block the IR but the camera can see it , and most of the red is blocked so it shows up as really bright white ...
But it is really bright white :p It's very visible light, not IR.
 
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there is no ir in red lasers! because they dont use an ir diode to make the red color, unlike green lasers :p
 
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I don't know if that is right or not, it was just a theory.
To proof it, someone will have to test it with a IR filter that bocks visible light.
I think that is is both visible and IR light. Because of all the heat, but what do I know ::)
It should be interesting  :D
 
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Well... that is true, radiant heat is caused by ir, but i am not sure if that is ir because we can see it. Ir normally isnt visible to the human eye (actually, I dont think that it ever is) Just my two cents :p
 
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Of course I meant test with a camera, IR is invisible to the eye :cool:
I have seen the white light myself in real life.

I can see 880nm from a led slightly as cherry red, and not any further.
 

Switch

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clwatkins10 said:
there is no ir in red lasers! because they dont use an ir diode to make the red color, unlike green lasers :p
Woot? :D That's not what it was about....they we're saying that the flashes are IR ...IR meaning heat You know, heat IS infra-red radiation, but it is of such a long wavelength, you're not gonna have any succes at all seeing it with a regular camera, IR filter or not.Our cameras pick up only NIR.

While because that spot gets hot enough to melt plastic, of course there is a lot of heat generated and thus a lot of this long wavelength IR ::)

BUT, the actual while flashes that we see are not IR....they may contain IR too, but that's not what we were discussing.We were discussing what we can see.....which is the visible light(duh!) :p
 
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GUYS! Look! It's a 3-D projector using this "sweet spot". I'm honestly very surprised that no one has seen this yet. They say that they use an infra-red laser to get it to the "sweet spot" where it makes plasma! The only thing different is that they project it out into mid-air, where as the sweet spot that we can produce only works when you point it at something.

http://www.aist.go.jp/aist_e/latest_research/2006/20060210/20060210.html

and

http://64.233.179.104/translate_c?h...ess_release/pr2007/pr20070710/pr20070710.html

Pretty cool huh! :cool: ::)
 

Switch

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Wow, nice! I see what they did there, except for the fact that I can't quite get how they'd make plasma from air? How powerfull is that laser? :-/ Anyway I bet it's pretty powerfull.....which makes that thing pretty dangerous....lots of reflections and stuff.Not to mention that sticking your hand in the 3D image space is excluded ::)

Anyway, I don't think it's the same effect....we concluded that our white flashes are incandescence, while the guys who made the scanner claim it's plasma :p
 
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Switch said:
Wow, nice! I see what they did there, except for the fact that I can't quite get how they'd make plasma from air? How powerfull is that laser? :-/ Anyway I bet it's pretty powerfull.....which makes that thing pretty dangerous....lots of reflections and stuff.Not to mention that sticking your hand in the 3D image space is excluded ::)

Anyway, I don't think it's the same effect....we concluded that our white flashes are incandescence, while the guys who made the scanner claim it's plasma :p

I know that you guys concluded that it is incandescence, but I personally would rather believe a bunch of Japanese scientists rather that a group of people gathered on a forum. I'm obviously not trying to offend anyone, but the Japanese scientists are probably very smart. ;) BTW, I think that plasma is just anything that is REALLY REALLY hot right? So the laser is just heating up the dust and other particles in the air.

PS: I have absolutely no clue how powerful a laser they are using, but I would definitely not want to stick my hand into the cluster of plasma balls. :eek:
 




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