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How to tell diodes apart?

lazer

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I put a few diodes in axiz modules and mistakenly never labeled them. Now I have a bunch of axiz modules and I don't know what diodes are in them. Is there anyway to test them to find out which diodes are in which without burning them out? I know they are either phr diodes or red diodes. (Not sure specifically which model of red unfortunately as I had a few different ones that I was putting in. I don't know what sled I took it out of either.)
 
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Cyparagon

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The can handle some reverse bias. If it were me, I'd just start probing it with low voltage (1.5V maybe?) and see if any light comes out. If nothing on low voltage, it might be safe to assume they're violets. Attempt at your own risk.
 

Ghostchrome

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Look at the glass on diodes. If it looks yellow, it's a blue diode. If it looks blue, it's a red diode. If there's no glass (soc or loc), safe bet it's a red. ;)
 
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lazer

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I'm trying the glass trick now. By yellow do you mean a goldish color? If so then I think I have 1 blu-ray and 1 red. Which would make sense since I believe these both came from a phr sled. Do you know the exact name of the red laser diode and how many mw is typical for it?
 
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Ghostchrome

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Yeah, the gold colored one will be the bluray diode. I'm not sure about the power of the red. I don't think it's very high if it came from a phr sled. Someone here will know better though I'm sure.
 
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Eudaimonium

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Is your "red diode" having three pins?

If it came from PHR sled, it should have four. And it's far too weak to spend an Aixiz casing on.
 

lazer

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Yeah the diode, I think is red, has 3 pins. Maybe it's a bluray then. I'm really not sure. I know I had 2 phr sleds and I took the blu-ray diodes from them. I have no idea what this one is. It looks much more blue on the lens than any of my 6x or phr blu-rays diodes look (all of those are a gold color). It can't be ir because it has that little lens. What's the name of the sled that has "LOC" in it's name? I can't remember exactly what it was called but from what I do remember it had a red diode in it. That might be where I got it from. I don't know for sure though because it's been so long.

Maybe I should just setup a low voltage driver for a red diode and give it a little current (80ma?). If it doesn't start with 3v then I'll up it to 5.5v. 5.5v is around where blu rays run so if its going to work at all it should work at that point.
 
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Isoleucine

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Like Ghostchrome said.

The glass can tell differenciate the laser color. The coloring of the glass is absorbent to the wavelength so that it does not reflect the laser light back into the diode's die/can.

A blue-er glass means that its a red 650nm diode, i.e absorbs red light.
An amber colored glass means that its either a 445 or 405 blue purple diode, respectively. It absorbs both light.
No colored glass is IR.
 

Eudaimonium

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Maybe I should just setup a low voltage driver for a red diode and give it a little current (80ma?). If it doesn't start with 3v then I'll up it to 5.5v. 5.5v is around where blu rays run so if its going to work at all it should work at that point.
Woah woah woah, a second please!

You do not "up to 5.5V" . We don't work with voltage, we work with current.
Constant current source.

You need to give them 100mA and see what they look like, no matter what red or bluray is it, it'll lase and NOT die on 100mA.

Voltage is another question. Blurays typically draw around 5.0V and reds around 3.0-3.2V, but that they choose for themselves, we only set the current.

What setup are you using? Pictures maybe?
 

lazer

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I think you misunderstood me. I should have been clearer. I know we don't work with voltage but if it doesn't start to lase at 3v 80-100ma then it should start for sure at 5v 80ma. It's either blu ray or red so it has to be one of those two voltages. I wasn't saying that I would keep adjusting the voltage. I was going to keep it at 100ma and use 3v first and if that didn't work 5v.

I did go ahead and test it though last night. It appears to be a red diode. I'm still not sure on what model it is but it's red. Is there anyway to tell its model?
 
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