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ArcticMyst Security by Avery

need an educated guess on 638nm

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Nov 21, 2012
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I was wondering if somebody who has experience with the mits 638 diode could give a ballpark guess on output power with this setup..

Mits 638nm open can diode
X drive 1.25a v6
2 x 18650 host
Thanks
 
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That would add up to a ZERO output as your laser diode is now dead from over current !


I was wonering if somebody who has experience with the mits 638 diode could give a ballpark guess on output power with this setup..

Mits 638nm open can diode
X drive 1.25a v6
2 x 18650 host
Thanks
 
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Why the 500mw one can take up to 1.4A? and I've seen builds with 1.4A on it.

I'm no expert but from diode to diode it would be 900mW to 1.2W with a G1 red lens.
 
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Wrong the diode is not dead and in fact works just fine.

It is the 500mw one. I even asked DTR when I bought the diode/driver and he said it would be fine. So far no issues at all with this setup.
 

DTR

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Some do push that diode that hard and it probably can take it but going over 850mA without active cooling can actually work against you making the output less visible due to wavelength shift associated with heat. There really is not any point to run them that hard in a handheld unless you just want to see a bigger number on an LPM. And there are some that do die when driven over 1A but it is rare and usually due to using a LED driver not a nice laser driver.:beer:
 
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I have this didoe in a host with a huge heatsink, and my run times are relatively short. I appreciate the input for sure!
 
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Sure it will work but for how long, I am only temporarily wrong keep using it at 1.25A and I will soon become right, you do know it was never designed
to take that much current, just because jim did it, wow, if jim jumped off a cliff would you :crackup:

I can never understand why people think they need to push every last photon out of a diode and run it over it's designed operating current,
wouldn't it be much better to run it at 1000ma and have it around for a year or so :thinking:

It's still going to be just as RED, you get longer duty cycles, it lasts longer, you spend less money !

Good luck, hope it runs as long as you want it to...
 
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No cliff diving for me...:undecided: I am new to the laser realm and this was my first build. It turned out good, but if I were to do it again I would go with a smaller driver! Hey this is a fun hobby and the learning process is part of the fun!!:beer:
 
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No cliff diving for me...:undecided: I am new to the laser realm and this was my first build. It turned out good, but if I were to do it again I would go with a smaller driver! Hey this is a fun hobby and the learning process is part of the fun!!:beer:

Welcome to the hobby!

And of course Lasers are fun(if you are mature to handle them).

I would love to see pictures of your build if you can provide them:beer:
 
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Here is a couple beamshots. One of just the red and another for comparison with other colors.
 

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Just to add to the mix...;) Im running a mits 500 at 1520 mA and it has been going strong for more than five months now and with no loss in power output (1053 mW). I also ran my first one at 1.35 A and that worked perfectly at 923 mW (month or so), until I decided to swap the driver and shorted it with the case in the process...

Admittedly visually it wont look any brighter than one running at 1 A and the wavelength will be shifted slightly. Although not recommended, if you want over 1 W, in my experience, youll need more than 1.3 A - diode dependent though.:beer:
 
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What DTR said is correct. I know you guys are talking pointers but I run 4 of these stacked pbs and corrected making 3.81w at 1.25a. It is kept constant 19c on a ovenind tec controller. I have run it continuous duty for 50+ hours with no drop in power as a test before deploying it as a modulated unit in a projector. Now has done hundreds of shows no issues.
 




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