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Zombie 445

Kenom

Kenom

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ok heres the long and short of this story. I was given a 445 diode (thanks daguin) and put it in a Kryton Groove. Originally I had it set at max for teh groove and was getting 650mw. I then moved that driver to a different host and threw in a rkcstr driver at max (450ma) and got roughly 300mw. I decided that wasn't enough so purchased a flex drive and jumpered it for max. Hooked it to the laser diode and fired it up and was getting a measly 50mw. I figured this couldn't be right so tweaked a little with the flex drive and was able to boost it up to 200mw. it was then I realized that the diode was probably fried. I then rehooked it up to the rkcstr so I could see comparison and at max on that, (450ma) it's outputting 100mw. The diode is very weak and the output is way different.

here is the output defocused and about 10 feet away.

Picture%205.jpg


not quite as defocused.

Picture%204.jpg
 





That sucks, think the cap discharged in to it or think it was just a weak diode?
 
Bummer :(

Since the "change" happened during a switch between installations, odds are something happened to the diode in the disassembly/reassembly.

Peace,
dave
 
i have had one of my 445nms got driven at 2a for only about 3 seconds and no light came out when it was driven that high but the second i turned down the power it came to life.
thats weird to see it like that tho
 
That looks like 3 distinct emitters!

Are we sure these are single emitter?

And you're sure its still lasing?

I suppose it can make a neat little pointer after all! That diode has been through a lot.
 
Meatball said:
That looks like 3 distinct emitters!

Are we sure these are single emitter?

And you're sure its still lasing?

I suppose it can make a neat little pointer after all! That diode has been through a lot.
Click to expand...

They are multi-mode. They all have the lines in them. They are just harder to "pick out" of the blaze at 900mW ;)

Peace,
dave
 
maybe solder a Lasorb onto it next time and leave it on between change overs.
 
Depending on how I focus mine you can actualy see multipal beams when looking from a side angle. Sorry to hear about your diode. These suckers are tough. Have one of mine being driven at 1.5A and have been using it a lot over the last week. No problems yet but I do have a few extra diodes from Daguin just in case.
 
If a diode is multi-mode, it doesn't necessarily mean it has multiple emitters.

I was under the impression that these were multi-mode, as well as single emitter, which allowed for their surprisingly allowable collimation.
 
Meatball said:
If a diode is multi-mode, it doesn't necessarily mean it has multiple emitters.

I was under the impression that these were multi-mode, as well as single emitter, which allowed for their surprisingly allowable collimation.
Click to expand...

Your impression is correct.
 
I've done more testing on this diode.. it's 'not totally dead, but it's sure taken a beating.

500ma = 100mw
700ma = 200mw
1A = 400mw
1.5A = 600mw
1.6A = 700mw
1.7A = 800mw

Now, this is in a Kryton groove and the output climbs big time if I freeze the head of the Kryton.. I was able to get the output to just shy of 1W on 1.75A when cooled.

A video of me cooling the head and watching the output climb
http://dl.dropbox.com/u/3175365/Video 1.wmv
 
Last edited:
Might be a blown emitter, like others said they have three.
I've had some success with totally dead shorted diodes by reverse pulsing them at low voltage/high current but not so high they blow out the bond wires.
 
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