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ArcticMyst Security by Avery

445nm Diode - LEDed?

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So...
I bought a 445nm build kit from Garoq about 2 weeks ago, and it just recently arrived.
I must say the shipping and packaging were very well done.
I followed the instructions and installed the diode as instructed. However, what I got was this:

The batteries were fully charged, and I could feel the heat sink heating up.

Is this diode permanently LEDed, or is it fixable in any way?
 





Garoq

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Hard to say, you might want to measure your battery voltage. I checked your setup before shipment and it was working properly then.
 
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mine was led'd by an ESD (static) and wasn't heating with very low output.
 
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Mine was very certainly heating, with about 5 seconds of CW output, the L(E)D 's heatsink already felt hot (about 50 degrees Celsius).
I checked the leads, they were in the correct direction, and the batteries were fresh off the shelf.
But certainly, this is an example of an LEDed diode, and it certainly will not be fixable, is it not?
 
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Oh yeah.. You can try direct driving on a full charged 18650 (don't flame me.. it don't damage the diode). If you cannot burn something black when focused, the diode is probably led'd (CODed) or zombiefied.

LED diodes can't be fixed, as the internal facets and all these smally things we don't know, have been burn't out.
 
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What do CODed/zombiefied mean?

Oh yeah.. You can try direct driving on a full charged 18650 (don't flame me.. it don't damage the diode). If you cannot burn something black when focused, the diode is probably led'd (CODed) or zombiefied.

LED diodes can't be fixed, as the internal facets and all these smally things we don't know, have been burn't out.
 
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COD stands for Catastrophical Optical Damage, it means that the facets, the Output Coupler or something INSIDE the laser diode has been completely destroyed, and can't generate a significant gain to emit light. I don't remember if this one mean "completely burn't" or "LED'd". zombiefied means the diode turned into a "zombie", it is a common term when the diode sucks 1~2A of current (or don't suck enough current), produce little light (in the order of 12, 10% efficiency or lower, instead of 25% common) and a lotta heat (or no heat, if can't suck current).
 
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My Guess is, You forgot to discharge the capacitors on the driver before hooking your diode up. Or when soldering you left the Soldering iron on to long on the pins witch heated up the diode to much and killed it.

Your diode is done there is nothing you can do to fix it. Just order another one and make sure to:
Rub the 2 leads that go to the diode from the driver together a few times and dont leave your sodering iron on the pins longer then a split second when soldering the driver leads to the diode.

Can you post a close up picture of the back of the diode with the leads of the driver still solder on.?

Dont ever hook up a 18650 directly to a diode it will most likely kill it instant.:tsk:
 
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@daguin
I'd like to see 30000 frames macroshot of a laser diode taking an ESD discharge, and see what goes damaged from very, very near :p
 

daguin

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@daguin
I'd like to see 30000 frames macroshot of a laser diode taking an ESD discharge, and see what goes damaged from very, very near :p

LOL! Maybe you should suggest this to PullBangDead. Perhaps he can work it into his PhD ;)

Peace,
dave
 
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I've watched a diode kill itself in a microscope, probably from overcurrent, not from ESD though. (I haven't personally ever had a diode die from ESD, even when taking only minimal precautions.)

But watching the damage happen live is pretty cool. The ones I've watched happen in a microscope ended up looked a lot like Dave's diode linked above, it can basically blow the top off the diode in a split second, but you can sometimes watch that damage start and then propagate across the whole length of the diode. Not that I ever try to damage diodes in research, I try to keep them around to test them again, it just happens sometimes.

I don't have the means to do any high-speed imaging in a microscope, that would take quite an investment. High-speed still images are not so bad, you can accomplish those with some pretty cheap equipment in general. But in conjunction with a microscope is a different story, and high speed video is definitely not within my means at the moment.
 
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Still interesting to hear. Hopefully someday I'll have to oportunity to see this too. ;)
I don't have all that knowledge about the phisics behind the diodes, laser cavities and so, but someday I will !
 




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