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Black vinyl tape vs "2.7W 450nm" laser

Seoul_lasers

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I was conducting some experiments with my new laser "cannon" from RHD in Nova Scotia, and remembered that I'd witnessed Carbon, especially Charcoal, put on a rather interesting fireworks display when was hit with a concentrated pinpoint sized beam from my C@$!0 projector lab laser. I immediately thought about black tape. 3M electrical tape was a good substitute as the tape is coloured by adding extra carbon to the PVC. PVC is normally grey-white.

2 parts to the movie,

1st part is an unfiltered look at the overwhelming blue beam. Note the white/yellowish flashes when laser touches the tape. Those are flame jets.

2nd part: I add a UV/blue filter (spare glasses) and you can see some optical trapping of carbon particles in the beam path. Also visible is a flare, caused in part by vaporized carbon reacting with the Oxygen in the air and the combustion of hydrocarbons in the tape.
without the filter this effect is impossible to see as the light overwhelmingly bright to the CCD. It's a blinding white/yellow.
Note, the beam is completely invisible though the filter.


-- note the laser I have is tested for 2.7W, at this power electrical tape pops "jets" explosively, at the finest focal point. This effect is apparent in the last part of the video.

Charcoal/ graphite is by far better a target as there isn't the acrid smell of burning PVC or soot strings that some plastics produce.



The video was produced on an iPhone 4S.
 

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Wolfman29

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Hey, mind editing C@s!0 out of your post? We don't post the name here otherwise their automated search engines will find us. And they don't like us :p
 

Seoul_lasers

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Hey, mind editing C@s!0 out of your post? We don't post the name here otherwise their automated search engines will find us. And they don't like us :p
whoops, edited out the name. Thanks for the heads up.

Sorry
 

Seoul_lasers

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Actually I was wondering, what was going on with the beam in the last part of the video.
 

InfinitusEquitas

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Interesting video... I haven't burned any electrical tape for a while now, but your video has certainly given me the urge:eg:

Thanks for sharing:beer:
 

Seoul_lasers

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actually looking further at the video there's definitely some optical trapping happening.
Carbon is undergoing thermoluminescence making the beam
Visible.
 

Flaminpyro

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If this is about carbon why are you using tape instead of charcoal ?

wouldn't there be a lot more carbon in charcoal than in tape :thinking:

I would like to see that 2.7W hitting some real carbon and get some good shots of the trapping.
 
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Seoul_lasers

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Yes, I got to go find some decent charcoal first. I was mentioning that a similar "explosive" effect could be found in tape due the fact that black electrical PVC tape has extra carbon in it to make it black. Charcoal is by far more spectacular.

I am working on a new laser meets Charcoal and Carbon for video.
Will post it soon.
 

Arayan

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Nice and interesting video :beer:

I am working on a new laser meets Charcoal and Carbon for video.
Will post it soon.
:pop:
 

RA_pierce

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I've noticed this effect with many materials including most plastics and wood.
I don't think it is optical trapping or carbon... The simplest explanation - and the one that makes the most sense to me - is that small particles of incandescent wood/plastic are being ejected from the surface.
 
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Arayan

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I've noticed this effect with many materials including most plastics and wood.
I don't think it is optical trapping or carbon... The simplest explanation - and the one that makes the most sense to me - is that small particles of incandescent wood/plastic are being ejected from the surface.
This seems to me the most likely interpretation :thinking:
 

Seoul_lasers

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Well, that's what I thought originally.
However, what I was noticing was a jet of intense white hot flame from my target surface. Charcoal, due to the fact it isn't pure carbon yet shows the effect the best.
Incandescent particles of carbon are being ejected.. Check! Agreed.
Wood doesn't show the bright hot flame though. Not like charcoal.
 
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FreeBee

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I would like to see this on an actual piece of charcoal as well. Make a setup so the beam and the charcoal are held perfectly still, it'd be much easier to see. ;)
 

Seoul_lasers

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Will do.
I plan on doing a video. I have to find a site that isn't locked up due to our idiotic real name law.
 

brian97cobra

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Will do.
I plan on doing a video. I have to find a site that isn't locked up due to our idiotic real name law.
not to hi-jack but can someone please pm me more details about making a video and then only using certain names and such....? just dont wanna make a vid and then have someone tell me to edit it.

thanks

as for the OP the vid looks really interesting.
 




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