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ArcticMyst Security by Avery

New red laser bought locally in South Korea

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Well I have a rathjer interesting story. I ordered locally 2 new DIY laser kits from
Gearab's store on Ebay Korea, and I got my package this morning at the school I work for.
So I open the package and in it are a seemingly mundane module with a glass lense (a supposed 650nm 350mW) and a 250mW 405nm blu-ray with a Constant Current DIY driver.

So, I go carefully and hook up the red to a 18650 cell to await first light. Immediately I notice the colour is red with a bit of orange in it. I focus the beam down to pin point to a target made of dark coloured paper and all of a hot white dot appears on the paper. It cuts paper in less than 1second and if it is focussed properly it does set fire to paper in about 3 seconds.
To tell you the truth this looks more like the damage my 1W 808 than what I have seen of the High power reds. Do you think my pentometer is up too high or is this normal in 350-400mW reds?
I do know after further inspection that this diode is an open can type probably from a 20x LG, at least my guess. They do 400mW?
This module does get very warm rather fast. I have been cooling it down with some refrigeration.

This has been a very interesting day as far a lasers go! :)
 





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400mW is a lot for an open can diode, but it is possible.
I've heard from my friend that someone has a red laser with an open can diode doing almost 500mW. But I'm surprised it can set fire to paper. I think you'd need more than 500mW to do that, though I could be wrong.
 
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400mW after optics from LOC diode is really difficult to achieve.

If a stock plastic lens is used , there is about 30% loss in power.
Meaning, if you were to get 400mW of red, you'd need Class IV red laser diode powered up behind it.

No LOC goes above 500mW limit.
Problem is that around 450 mW , the efficiency of the diode drops drastically and more amperage you feed it, it will just get warmer with very little power increase.
And eventually it will die.

Setting fire on paper with simple single-mode diode system is impossible.

I have no idea what kind of paper are we talking about, but I know that I did not manage to ignite a paper with >600mW of IR.

So even if you actually do achieve 400mW output, you are still not getting the paper on fire. Unless you soak it up in gas and get some gunpowder on it.

And to achieve 400mW of diode output, before the lens, one would need to shoot over 550mA in it, maybe 600 mA even.
That means a HUGE capacitor bank is needed, to soften the startup as much as possible, otherwise the diode is just going to heaven.


Seoul_lasers, care to take some pictures, and explain better what do you mean?
 
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the only thing you could set on fire close to paper is flash paper.... red just wont do the job, most of the energy in the red dot/beam will be reflected and very little will be absorbed.

stuart :)
 
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the only thing you could set on fire close to paper is flash paper.... red just wont do the job, most of the energy in the red dot/beam will be reflected and very little will be absorbed.

stuart :)

Well, true, but flash paper doesn't burn it deflagrates and quickly! Actually I think I might try some out for my next demo. ^^

Anyways, I think all and all it might be the paper allowing for lower temp ignition because card stock just seems to smolder. no flame. black tape cuts instantly

Btw, this diode and driver contains a HQ glass lens, NOT an acryllic lens. Diode is Open can.

I am running this driver stock without ANY modifications. A little suprised.
(Gearab) said this diode does over 350mW with an acryllic lens--. I'll say it's doing over 350mW!

Kinda strange that I got these rather spectacular results from a stock kit. I am going to take HD video of the diode once I get a better heat sink and cooler for it.
I am going to use it in a labby build.
 
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Well I have a rathjer interesting story. I ordered locally 2 new DIY laser kits from
Gearab's store on Ebay Korea, and I got my package this morning at the school I work for.
So I open the package and in it are a seemingly mundane module with a glass lense (a supposed 650nm 350mW) and a 250mW 405nm blu-ray with a Constant Current DIY driver.

So, I go carefully and hook up the red to a 18650 cell to await first light. Immediately I notice the colour is red with a bit of orange in it. I focus the beam down to pin point to a target made of dark coloured paper and all of a hot white dot appears on the paper. It cuts paper in less than 1second and if it is focussed properly it does set fire to paper in about 3 seconds.
To tell you the truth this looks more like the damage my 1W 808 than what I have seen of the High power reds. Do you think my pentometer is up too high or is this normal in 350-400mW reds?
I do know after further inspection that this diode is an open can type probably from a 20x LG, at least my guess. They do 400mW?
This module does get very warm rather fast. I have been cooling it down with some refrigeration.


This has been a very interesting day as far a lasers go! :)
I have a couple of red labbies that output >380mW using the 650-G-1 lens.
Do not refrigerate your laser!!!
Turn it off and set it down.
Most electronic devices do not like sudden temperature changes, lasers included.

Setting fire on paper with simple single-mode diode system is impossible.

I have no idea what kind of paper are we talking about, but I know that I did not manage to ignite a paper with >600mW of IR.
I have been able to light very thin, Sharpied Rice-Paper on fire before @400mW, but it took a while. (the Sharpie's ink might may have made the paper more flammable)

Seoul_lasers:I am running this driver stock without ANY modifications. A little suprised.
(Gearab) said this diode does over 350mW with an acryllic lens--. I'll say it's doing over 350mW!

Kinda strange that I got these rather spectacular results from a stock kit. I am going to take HD video of the diode once I get a better heat sink and cooler for it.
I am going to use it in a labby build.
Compare yours, to mine in this video.
YouTube - Fun with 510mA LCC.WMV
That will give you an idea of how much power it has.
Pay attention to the time it takes to light matches and burn through a CD case.
I think you might have to revise your >350 guess.:D
 
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I agree with the above post. Definatelty NOT ~500mW!! but I do think it is getting closer to 400mW. Today I tried the CD case. It punches it in about ~3-5 seconds. I tried a few different kinds of dark paper. A4 black seems to ember if I get a slightly wider focus, more surface area exposed to the hot beam. Rice paper lights without too much effort.
I think next experiment will be to try a candle.. Again I will post the results in HD.

I want to make a Phaser build with that 510mW diode! Yummy!
 
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A4 black seems to ember if I get a slightly wider focus, more surface area exposed to the hot beam.

errm i don't really think thats right...

its actually the smaller the point the better for burning, if you have your laser defocused so that the spot is wider you wont be burning anything.

I want to make a Phaser build with that 510mW diode! Yummy!

its 510 milliamperes not 510mW...

stuart :)
 
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I did say slightly larger, didn't I... The focus is still more than enough to burn.

Why are you using mA instead of mW? I am talking mW here. All diodes have a different current capability so the mA isn't that important when I really am after the light output in mWs.

Only further experimentation will tell me just how much optical power it is outputting.
I'd like to get my hands on an LPM.
 
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I did say slightly larger, didn't I... The focus is still more than enough to burn.

Why are you using mA instead of mW? I am talking mW here. All diodes have a different current capability so the mA isn't that important when I really am after the light output in mWs.

Only further experimentation will tell me just how much optical power it is outputting.
I'd like to get my hands on an LPM.


no you are actually the one who is talking mA instead of mW, if you read back im sure you will find it...

you clearly stated 'i want to make a phaser build with that 510mW diode!' when clearly in his youtube video that it is 510mA not mW, no LOC/LCC will reach 510mW.

stuart :)
 
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no you are actually the one who is talking mA instead of mW, if you read back im sure you will find it...

you clearly stated 'i want to make a phaser build with that 510mW diode!' when clearly in his youtube video that it is 510mA not mW, no LOC/LCC will reach 510mW.

stuart :)
Umm...
That may not be entirely accurate.

2 years ago, post made by Billg519.
LOC laser, shooting out exactly 510mW from it's business end, measured by professional LPM.

How the hell did I forget that?

He explained that he soldered wrong components on the driver somehow, and result was a class IV 650 nm red handheld.

I must ask him about that...
 
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Umm...
That may not be entirely accurate.

2 years ago, post made by Billg519.
LOC laser, shooting out exactly 510mW from it's business end, measured by professional LPM.

How the hell did I forget that?

He explained that he soldered wrong components on the driver somehow, and result was a class IV 650 nm red handheld.

I must ask him about that...

That's what I was talking about in post #3. But it's also a possibility that it was a freak diode. Also could you provide the link to that post if you can find it?
 
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That's what I was talking about in post #3. But it's also a possibility that it was a freak diode. Also could you provide the link to that post if you can find it?
Hardly - forgot the name of the thread, it could be so old that it's possibly deleted.

I'll shoot Bill a PM and let you guys get the first hand info on the subject.
 
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that must have been the most efficient, freak diode that anyone has/will ever know!

but in reality, normal LOC/LCC would not shoot out that much power, its only the very few that make it into 'class IV' without LEDing.

stuart :)
 
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that must have been the most efficient, freak diode that anyone has/will ever know!

but in reality, normal LOC/LCC would not shoot out that much power, its only the very few that make it into 'class IV' with LEDing.

stuart :)
PM sent, fingers crossed.

Bill is offline though, might me hours until he replies.

No diode like that one ever again I guess, too.
 




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