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How to identify 520nm Diode with confusing labeling.

Immo1282

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Hi all, I ordered a PL520B diode from Ebay from this listing "Osram PL520B 520nm 80mW Green Laser Diode 1 PCS/3.8mm/Brand New" but when it arrived, it was labeled in it's container "520 50". I contacted the seller and haven't recieved a reply yet - but I was wondering if anyone here knows how to identify whether this is indeed a PL520B 80mw diode, or the lower rated PL520 50mw...

I ask cause the driver I'm going to use this with is not pot-set (Lazeerer Nano-Drive v6 sourced from DTR), and it's minimum current output without modification is 275mA (i.e. too much for a PL520)

The diode base is unmarked, but the can has the markings "7A 63" on it if that's any help.
 

paul1598419

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I have not purchased this diode, but I have purchased many items from Existotem, Newgazer and Techhood. They are all the same company, so if you are asking questions of them you contact Robinson. I have not had them sell me a different laser diode than the one they claimed to have out for purchase. If you are concerned, I would contact them before using it.
 

Immo1282

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O
I have not purchased this diode, but I have purchased many items from Existotem, Newgazer and Techhood. They are all the same company, so if you are asking questions of them you contact Robinson. I have not had them sell me a different laser diode than the one they claimed to have out for purchase. If you are concerned, I would contact them before using it.
Thanks Paul, I'm sure it's what they sold me, just the way it was labeled wasn't so clear! I'll send them a message before I test and install it.
 

DTR

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They do look pretty much identical. You can tell for sure two ways. The forward voltage is lower on the PL520B and the spot with a G-2 had a crazy line though it from a dye reflection on the PL520 that is not there on the PL520B. I have given up making any sense of the codes on the Osram diodes as they are different with every batch I get but the PL520's I have now are all 83 and the PL520B's are 63. There is some differences I have spotted under magnification. There seems to be what looks like excess solder between the dye and the mount on the PL520B's.









 

paul1598419

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That is much more than I knew about these two diodes, Jordan. I do see what you are talking about, but I do wonder if that is actually solder or something else. Still, that is enough information to set one up on a CV/CC supply with a single element aspheric lens to see if that artifact is present or not. As far as Vf goes, I would need samples of both diodes to tell which has the lower Vf at threshold. Thanks.
 

Immo1282

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Thanks a ton Jordan - I'll see about looking at the end under magnification tomorrow.
 

hakzaw1

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Awesome macros Jordan-- TY for taking and posting them for the greater good..
 

Immo1282

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Borrowed a microscope from a neighbour and had a look - looks like a PL520B thanks to your photos Jordan. Seller confirms this.
 




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