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Best surface for laser beam absorption?

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I was testing several surfaces that absorbe the most of light and energy from high powered lasers, reducing light reflection without getting any damage.

I got better results with black stone and cast iron, but they have a general diffuse light reflection, indeed.. not very dangerous for eyes, but i was wondering if there is something better?

I got 100% results with black cloth...but (of course) is ok for low powered lasers that dont burn, other powered laser will firestart immediately...

I got bad results with fireproof black paint (too much reflective) and black glue for chimney (xs reflective too).

Any suggestion?
 
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RA_pierce

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I use a slab of stone painted with matte black (no gloss) spray paint. This works well for lasers with low power density. >500mW lasers with <2mm beam diameter can ablate the surface of the paint.

Graphite is a great beam dump.

If you want an almost perfect beam stop, I have made one out of a flashlight tube. I designed it to "trap" the beam. Perhaps you can get creative an make one too.
 

GBD

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I second RA's advice,
Ive done something a bit different, but its still the same concept.

I used a 3" diameter black PVC pipe, an endcap at the end, and a piece of matte painted aluminum stuck at the back and inside the pipe. (so I can use higher powers and not melt the back)

Works on the same concept, the only reason I did it this way is while you are stopping the dot, the flashlight style wasnt wide enough to get rid of some artifacts and scatter I usually have. there is still some scatter left on the edges, but it really gets most of it around the dot itself.
Great in darkness, you can see the beam better as not much light from the dot itself can distract from that.
 
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i tried spray paint matte black, not the best choice on any surface for high powered laser with long duty cycle.. they easily get rid of the paint and go behind whats after...

i should try with some terrain... still dont know how to keep it in vertical position, anyway !
 
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I remember reading something about razor blades.... oh here it is:
Beam dump - Wikipedia, the free encyclopedia
i thought already to water with ink or black paint into a glass cube.. anyway glass, has a partial beam reflection...

black anodized aluminium...i dont think is a better choice than cast iron...though, small steak grills are more affordable and easy to get. :)

yet, someone may sell painted aluminium instead of black anodized, and you never know that after a long duty cycle you get a full beam diffuse reflection from a silver surface.
 
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glowdye

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Here is a beam dump used by the department of defense. buy a stack of razor blades, bolt them together so that there is a surface of many edges. take that to a candle and soot up the blades. The soot absorbs the light and the razor blades act as a almost perfect blackbody.
 

donprado

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Here is my design:
take a standard copper tube, length about 15-20 cm. Solder an endcap on one side, and probably a nut on the outside to connect a stand.
Then bend the tube by 90 degree and blacken the inside with a candle.
With this simple design, the laser will be absorbed in the tube, and the reflected part will be reflected further inside to the closed end and there absorbed. The good heat transfer of copper allows to use this dump with quite high powers. I used this design very often in our university lab with different lasers. Worked very well :beer:
 

Meatball

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^^^Both of these methods work great if you do them well. They should be all you need for a very nice place to dump your beam.
 

Laserburns

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Here is my design:
take a standard copper tube, length about 15-20 cm. Solder an endcap on one side, and probably a nut on the outside to connect a stand.
Then bend the tube by 90 degree and blacken the inside with a candle.
With this simple design, the laser will be absorbed in the tube, and the reflected part will be reflected further inside to the closed end and there absorbed. The good heat transfer of copper allows to use this dump with quite high powers. I used this design very often in our university lab with different lasers. Worked very well :beer:
that's a nice design that i should try next time..

i made already several laser dump (probably will sell some of them in the appropriate area) i used several materials combined, like cast iron with black stone as shield, for one kind, and aluminium with a special material i asked to a service, made with dust of black stone and liquified iron, for shield, into another.. that is amazing (also expensive).

then, there is Captain America, the best of all of them in progress, will be finished within this weekend:

http://laserpointerforums.com/f44/coolest-beam-dump-blocker-world-60336.html

http://laserpointerforums.com/f44/captain-america-vs-lasers-60481.html
 
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