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Unfocused Burning?

wcutrumpetkid

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I've recently added a new laser to my collection, a 3000mw 450nm beefy looking mod from Laserpoints.com. I'm a novice when it comes to laser experience, but I'm in no way a dunce. I plan on doing some rigorous safety tests when it arrives in the mail, but I would like to know if the beam has the capability of burning without being focused. If I were to point it indoors (with glasses ofc), would it burn my walls or furniture? Not point blank, just showing off the beam etc.
 



Nexgen

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Depending what color of walls do you have. I have white-painted walls and even 6watt focused to infinity wont do anything to my wall. I recommend to use black painted brick or beamstop to stop the beam. But it will burn your furniture easily, so watch out. Stay safe and don’t do anything before you surely know you are doing.
 

Encap

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A laser beam has no temperature - there is no inherent "temperature" to a laser beam. Heat is the random motion of matter particles (atomic or molecular particles).
A laser beam itself is not made of matter but of photons, which have no mass, thus a laser beam can have no temperature.
"Heat" is caused by a laser beams energy being absorbed by a materials surface and turning light energy into heat energy.

Depends upon the ability of the target to absorb and convert the light energy to heat.
 
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lasersbee

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^^^ What he said ^^^^ as well as...

It all has to do with Power Density... and the
target surface.

The Sun will not ignite a 3" diameter spot on
a newspaper. But use a 3" magnifying glass
and focus that same Sun to a pinpoint and
the newspaper will cat fire.

Jerry
 
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CurtisOliver

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...cat fire? Poor cat! :D

As the others have put nicely, surface and beam intensity is important.
 

diachi

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Depending what color of walls do you have. I have white-painted walls and even 6watt focused to infinity wont do anything to my wall. I recommend to use black painted brick or beamstop to stop the beam. But it will burn your furniture easily, so watch out. Stay safe and don’t do anything before you surely know you are doing.

Depending on how close you are/how good the divergence is, it could burn white walls/blinds too!

I've got scorch marks on my blinds (white) from a 2W dual A140 with beam correction, had it all the way across the room.

Good advice on the beam stop! :beer:
 

CurtisOliver

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Yes, white objects do burn with 2W+ I've found too. I had a M140 at the time.
 

paul1598419

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That depends on the power density of your beam. The smaller the spot for a given power, the greater its power density. I have a 3 watt 445nm and it depends on how small I can make the dot. These are all multi mode diodes and it depends a great deal on the optics how small that dot can be made to be. For the most part, they don't burn white walls or blinds or paper. If you use optics that can get the dot small enough then yes it can.

I really doubt your new laser you bought will have optics that will be able to do this.
 

Alaskan

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A laser beam has no temperature - there is no inherent "temperature" to a laser beam. Heat is the random motion of matter particles (atomic or molecular particles).
A laser beam itself is not made of matter but of photons, which have no mass, thus a laser beam can have no temperature.
"Heat" is caused by a laser beams energy being absorbed by a materials surface and turning light energy into heat energy.

Depends upon the ability of the target to absorb and convert the light energy to heat.
Damn, there goes my plans for a new laser heater!
 

Radim

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My WL Evo is pretty good unfocussed burner. ;)
 

Richie89

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A laser beam has no temperature - there is no inherent "temperature" to a laser beam. Heat is the random motion of matter particles (atomic or molecular particles).
A laser beam itself is not made of matter but of photons, which have no mass, thus a laser beam can have no temperature.
"Heat" is caused by a laser beams energy being absorbed by a materials surface and turning light energy into heat energy.

Depends upon the ability of the target to absorb and convert the light energy to heat.
well said Encap :)
I actually figured this out last year when I conducted a tiny experiment by firing my half watt 638nm onto my hand and feeling almost no heat at all but doing the same with my half watt 445nm, it burned pretty good it was at this point I figured out that a laser beam doesn't actually carry heat or thermal energy in the beam itself. very cool indeed
 




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