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ArcticMyst Security by Avery

DEGRADED 8x: Free to a good home.

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I have an 8x BR diode harvested from an LG-BH08 bluray burner. As far as I can tell it was the first one ever harvested on the forums. I've been using it about a year now, and have treated it as gently as I can. One way or another, either through improper heatsinking (unlikely), bad drivers (somewhat probable), or just plain bad luck (definitely possible), it's gone and "degraded".

It now projects a disgusting black halo around the centre of the beam. Check this thread for some pics: http://laserpointerforums.com/f38/8x-br-diodes-42806-8.html#post661598

This seems to be a (somewhat) common way for 8x diodes to fail, it happened to misterwilling as well: http://laserpointerforums.com/f38/8x-diode-degradation-42088.html

I'd really like if someone out there with the proper equipment could take this off my hands and tell me how and why this happens. The most this diode was exposed to is 1minute on at 350mA in a jayrob sidebutton host. I noticed this behavior after I transplanted it into a whitefusion build at 300mA. As far as I know, it's never been treated badly. I always try to ensure things never get the slightest bit warm.

I've offered this to IgorT, but he never responded to my PM/emails, so this is up for grabs.

The first person who can reasonably convince me they have the equipment and knowledge to properly test this, can have it. If you live in Antarctica or the ISS or someplace, and you want super duper fast same day shipping with signature confirmation and DNA test, I may ask you to pay partial shipping, but otherwise the diode is free.
 





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Thanks for the rep, everyone who's done so, but really it isn't necessary.

This diode is probably unfit to use in any real laser, it's probably about to die soon. Its output has diminished to that of a PHR, so you're not really getting a great diode here. My intention is for someone with a microscope, LPM, etc, to test this diode destructively, then post the results here so we can figure out more info about how these diodes die.

Nevertheless, DLMB has first dibs in case no one else responds.
 
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Thanks for the rep, everyone who's done so, but really it isn't necessary.

This diode is probably unfit to use in any real laser, it's probably about to die soon. Its output has diminished to that of a PHR, so you're not really getting a great diode here. My intention is for someone with a microscope, LPM, etc, to test this diode destructively, then post the results here so we can figure out more info about how these diodes die.

Nevertheless, DLMB has first dibs in case no one else responds.

Well no microscope, BUT I do have a LPM, and would love to do a bit of testing! :eg: I have a DMM too... I have never killed a diode on purpose, should be fun!

EDIT: Woops, looks like I mis read :( I have it until someone else responds? Another PM sent!
 
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:bumpit:

If anyone has a data logging LPM, a reliable driver, two multimeters, a microscope, a camera, and an hour of free time, please PM me in the name of SCIENCE!
 
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I have an LPM (theoretically could do data-logging, but I haven't achieved it before), a selection of multimeters, camera, possibly access to an IR camera (If de-canned and with a bit of luck and lenses, I can see heat-flow and temps, though would need to somehow coat the metal in a non-IR reflective paint to allow emission), and possibly a lab PSU too. I'm not so sure about the free time though, what kind of testing procedure were you thinking? This is all my school's equipment except the camera, LPM and multimeters, so the time I actually get to use it may be limited.
 
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I have an LPM (theoretically could do data-logging, but I haven't achieved it before).

Well, I guess that's not important really, you could do data logging with a pen and paper if need be... Basically I was thinking someone could measure its voltage and output over a range of currents, then de-can it, inspect the die with a microscope.. Then re-run the curves de-canned, inspect it with a microscope again, then gradually increase current till it dies, then take some more microscopic pictures so hopefully we can watch the degradation progress.

I'm not in any sort of hurry, this diode is useless to me and I'd just as soon toss it in the garbage, but if we can learn any meaningful information about how these things die, I think it'd help us all.


are you sure its the diode and not the lens?
The pictures in the thread linked above are shot with no lens in place. I've also taken a good look at the window and there's no damage to it.. I've also cleaned the window with rubbing alcohol and a q-tip, and it didn't change anything. I'm pretty sure the die itself is degrading.
 




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