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FrozenGate by Avery

Is a non IR filtered green HOTTER?

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Jan 11, 2009
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Is a nonfiltered 532nm laser as good as a filtered one for burning? What about brightness? I would think a non filtered 532 is hotter right if your getting 532nm and 808nm for burning right, any major difference in burning? Is Rayfoss as good as O-like?
 





I think so, but really have no idea....i'm waiting for an answer also :)

Me + DPSS = FAIL
 
Someone correct me if I am wrong, But logic mandates that if there is significant IR passing with the green, you will have a Hotter laser.

IR is a longer wavelength and therefore more damaging.

This will have zero effect on "brightness" since the human eye cannot perceive (see) IR.

I still don't understand the fascination with burning things.... Whatever happened to experimenting with optics, mechanics & physics?
 
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I would think unfilitered is best for burning because you get higher mW in both green and IR.
 
Someone correct me if I am wrong, But logic mandates that if there is significant IR passing with the green, you will have a Hotter laser.

IR is a longer wavelength and therefore more damaging.

This will have zero effect on "brightness" since the human eye cannot perceive (see) IR.

I still don't understand the fascination with burning things.... Whatever happened to experimenting with optics, mechanics & physics?

Not exactly...

The term "hotter" doesn't really work here.
A beam of light is not "hot." Lasers burn some materials because that light is absorbed, which is what creates "heat."

The IR leakage does add to the total power of the laser, but not significantly. Generally, IR leakage only accounts for 10-20% of the total light output (or up to 30mW) in green lasers from 5-100mW. This does not increase the laser's burning ability by a measurable amount. IR has a different index of refraction than green, so it is not collimated or focused as well as the green output. Also, the IR spill is usually not in a nice uniform Gaussian beam, but instead it is multimode, distorted, and somewhat blocked by the various optical elements and the aperture.

The term "damaging" is also very vague. If you mean IR is better for burning, that is not the case. How well a laser burns depends on several things including the absorption of the specific wavelength by the material, what the material is (metal, plastic, wood, etc.), power density, total output power...

You are right that brightness is not affected.



The short answer is: No, IR spill does not increase the burning ability of a green laser, nor does it make it brighter.
 
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Well said, adds clarity. Appreciate it.

Does IR absorb more readily than visible wavelengths?? There must be a reason why laser cutters and routers are IR.
 
IR can be achieved cheaper and easier than the visible wavelengths, so they go with that. I think.
 
Well said, adds clarity. Appreciate it.

Does IR absorb more readily than visible wavelengths?? There must be a reason why laser cutters and routers are IR.

It depends on what you are calling IR.
808nm is more accurately described as Near Infrared.

Cutters and etching machines usually use 10.6µW (10600nm, CO2 laser) which is absorbed by pretty much anything including glass and "transparent" plastics. Gas lasers typically have very good beam quality which makes them very precise for cutting/etching/drilling. This, and the low power-to-price ratio, makes IR lasers a good solution.

Near IR like 808nm from DPSS green lasers has similar absorption to red (650-660nm) lasers like our DVD burner lasers.

Visible wavelengths are not absorbed by as many materials and multi-Watt Visible wavelength lasers are very expensive. Coherent produces this: Coherent Inc. : Mamba
Watch the video.

Using UV for this purpose would just be immensely dangerous and impractical- I would imagine. I've never heard of a UV laser used for cutting or etching, but they may exist.
 
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Oh I understand that a compact high power c02 laser is cheaper to manufacture and operate than a comparable visible unit.

But I am fairly sure absorption plays some role as well.

Edit - Thanks again.
 
Well, formerly, if ou have IR together with the green, ofcourse you have more power coming out from the laser ..... but there is a problem ..... First, IR is not in the same divergence of the green, second, is a different wavelenght, so the focus is not the same ..... for DPSS modules, usually, when the green beam is focused to infinite, the IR part is diverging some degrees, and if you focus the IR to infinite, the green is focused usually some cm out from the module, then diverge again ..... as far as i know, there's no way for take a DPSS module and have green and IR parts both focused at the same point .....
 
So a infrared filtered green laser is much better because its all green rather than a mix of two powers right? It's kind of like 14k gold rather than 24k...
 
So a infrared filtered green laser is much better because its all green rather than a mix of two powers right? It's kind of like 14k gold rather than 24k...

Some how, i think you would rather have the 24k gold. It's Gold Bullion..
 
If you meter your laser with a Thermopile LPM and it out outputs 200mW
then you have 200mW of usable beam power... a mW is a mW...

As was already mentioned above... the burning ability of any Laser
depends on...

1) the smallest point that you can concentrate (focus) the beam
to with your optics.. That will increases the mW in relation to the area
of the beam... (more power density)

2) the color/surface of the material you are burning...

3) the wavelength of your Laser...


Jerry
 
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But wouldn't a non infrared filtered green laser measure 200mws if it has 150mws of green and 50mws of infrared?

So then an a IR filtered green laser is a real green laser
 


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