How many MW do I need to burn paper?

[Jeremy The Wicked]

So I'm not an expert regarding laserpointers, but I was hoping you guys could tell me how many MW I need to burn simple office paper?

:thanks:

P.S I'm not a pyromaniac, I'm a survival enthusiast and I'm building a professional kit. For fire I already have water-proof matches and a flint stick but would be nice to have a laser too

 

[Fretwrecker94]

In terms of MW (MEGAwatts) you only need about .000001....

In terms of mW (milliwatts) you need 1000mW

Hobby lasers are more commonly measured in milliwats (mW) just because they're more readily available in the mW range. Search the forum, do some research, build a laser

*EDIT* as an answer to your edit, I'd say that a laser is not the best "survival" tool. But I agree they are nice to have!

*EDIT #2* Also, if you wanted something to, say, just light a match, you can do that with much lower power. I wouldn't recommend a 900mW+ laser to someone just starting out.

 

[Sigurthr]

I picked up a 200mW 650nm (red) waterproof focusable laser from Laserlands a few weeks ago and it burns white paper quite well even when not focused perfectly. It is model 601-T which is $60 w/ free shipping. Very ruggedly built, thick aluminum housing, clean deep threads, can't addicently disassemble the focusing head (which would negate the water proofing), and even has a second glass protection lens after the focusing lens, which I find important in a "go pack" laser.

Since then I learned about (and started purchasing from) Lazerer which has many similar lasers for less money, but wanted to point you in both directions. Always go with the lowest power necessary for safety.

In a real survival situation you may not have access to laser goggles, and a 1W laser will leave you blind if you try to burn paper with it unprotected. Now, I am NOT saying you can stare at a 200mW laser trying to burn paper and it won't damage your eyesight either, as it would, but it would be less risky. You'd probably have to try to set the laser down at the right distance from the paper/kindling with it off, then turn it on and look away while it ignites (hopefully), and then turn it off and try again with a different distance. I might be comfortable doing that if absolutely needed with a 200mW laser, but I wouldn't try it with a 1W.

As said before, for starting a fire, there are much better tools.

Personally, my 200mW red "survival tool" laser is for wild animal protection and night adapted vision augmentation. With a properly defocused (diverged) 650nm beam you can safely use it as a spotlight to see in the distance when your eyes are dark adapted without screwing up your dark adaptation. And should you encounter a bear or wolf or what have you (we have those up here) you could temporarily flash blind it or drive it away enough to escape.

 

[Fretwrecker94]

I picked up a 200mW 650nm (red) waterproof focusable laser from Laserlands a few weeks ago and it burns white paper quite well even when not focused perfectly.

Your 200mW red laser burns white paper? That seems a bit odd. But probably means the laser is pretty overspec!

 

[Sigurthr]

If so, that's awesome! Haha, it's the highest power laser I've ever owned, so I really have nothing to compare it to. I don't really burn much at all, I just wanted to see what it could do one day. When focused to <0.5mm it will burn through 5mm of black plastic very easily.

As I said before I mostly use it for nocturnal spot lighting outdoors. I spread the beam to about 15-20ft across @ 300-400ft or so. It's bright enough to clearly see what's out there without it affecting my dark adaptation and no dangerous reflections.

 

[joeyss]

^ You may want to look into getting a 100 or 200mw green for that. You'll be able to cover a wider area or see much more detail like the reflective eyes of a animal much better. In darkness red is actually dimmer due to the wavelength shifting more towards blue in your peak vision.

 

[Sigurthr]

Aye it is dimmer, but it also doesn't reset your dark adaptation, which green does very quickly. Also, it is less affected by Rayleigh scattering, so you see less of the beam and more of the spot. The reason it works better than a standard flashlight is in complete darkness the contrast between the beam path and the target is reduced due to scattering of the shorter wavelengths, and also a flashlight would reset your dark adaptation.

 

[LazerMann]

Strange Thing..

Hello all, Well. I buyd a 1000milliWatts green laser pointer. It has 532nm, I have readed that i can burn matches and paper with this.. Well, I was wondering if it could. So i tried it out.. But it didn't burn or match anything. Why is this? Or how can i make it does? Thanks! :thanks:

 

[daguin]

Because the person/company that sold it to you lied about how powerful it was

Try focusing the beam with a magnifying lens to a small dot

Peace,
dave

 

[Livinloud]

well, i bet they said output<1000mW so they didn't technically lie :crackup:

oh i love how these companies get away with this crap!

 

[kecked]

Get a 1064nm laser or CO2 laser. I’d bet most greens dpss burn from 1064nm leakage.

 

[paul1598419]

You know the last time anyone posted to this thread was almost 7 years ago. To the best of my knowledge, no one who posted here originally is still active here now.

 

[kecked]

Why did it come up in the new posts? I guess I should have looked at the date. Not like I searched for it.

 

[paul1598419]

I donno. just thought you'd like to know.