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Osram PL520 50mW 520nm Laser Diode

I took ARGlaser's advice and used Google Docs. WAY better than excel!
Also, I had to do a bit of searching to find ApexProxy's data. All I found was a few numbers from a murder fund thread.
Let me know if there is more data and I will add it.
PL520graph2_zps86f9a7fa.png
 
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Wait the diode I sent him hit 130mW without cooling?:thinking:

I am thinking there has to be cooling as his line shows a sharp increase in efficiency from 200mA to 300mA.
 
ApexProxy said:
I even compared it side by side to 532nm when I ran it at 300mA with just a heatsink as well as when it was TEC cooled at 400mA. Both times made the 532nm look ugly.
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ApexProxy said:
Hit 164mW at 400mA on my TEC unit. I didn't hold it there because I feared for the diode.
Click to expand...

ApexProxy said:
I kept pushing further and I found the efficiency wall to be 350mA at 130mW anything over and I started losing output. I believe 300mA for 120mW to be a nice solid max for my diode.
Click to expand...

This implies he only used a heatsink at 350mA to get the 130mW he said he got. Also, on his TEC cooled 400mA, he appeared to get 164mW.

Hopefully he can shed some light on how each of his measurements were taken.
-Isaac
 
@wannaburnstuff ^That is the data I used.

wannaburnstuff said:
This implies he only used a heatsink at 350mA to get the 130mW he said he got. Also, on his TEC cooled 400mA, he appeared to get 164mW.

Hopefully he can shed some light on how each of his measurements were taken.
-Isaac
Click to expand...

DTR said:
Wait the diode I sent him hit 130mW without cooling?:thinking:

I am thinking there has to be cooling as his line shows a sharp increase in efficiency from 200mA to 300mA.
Click to expand...

Very odd curve especially compared to what DTR has.
More info on test procedure is needed. Also, more test points are needed.
With only 3 points it's hard to say what is going on.
 
I am also looking forward to the murder tests coming up. All of that combined should give us quite a bit of information regarding these diodes and how they handle the almighty mA.
 
RA_pierce said:
Agreed. I've been waiting and planning a long time for this.
But I think I will have to wait a while longer because I want at least 150mW of green.
And I mean 100-150mW rated by the manufacturer diodes. Not that overpowered, reduced lifetime bullcrap.

It would be nice to finally have a collection of 405, 450, 520, 638, 660nm all with single-mode diodes. But the yellow/orange and blue wavelengths are still missing (450 isn't blue - it's indigo if you ask me :P).
Click to expand...

I thought I was the only to think that. Right now my C6 collection consists of 405, 445, 450, 520, 638 and 660. I'm thinking about adding a 685. The only MM out of those is the 445.

I wish I had about 100 grand to get some yellow, orange and blue diodes.
 
Dr_Evil said:
I thought I was the only to think that. Right now my C6 collection consists of 405, 445, 450, 520, 638 and 660. I'm thinking about adding a 685. The only MM out of those is the 445.

I wish I had about 100 grand to get some yellow, orange and blue diodes.
Click to expand...

You could build a 532nm and a 780/808nm to complete the collection. These are commonly available colors.
 
IR just doesn't interest me that much unless it is something like a 20W plus gas tube. As for 532, I'm wanting to avoid using DPSS modules in the collection.
 
Jordan,

I suppose the Vf increase at lower temperature is due to there being less charge carriers available in the diode junction, requiring a slightly higher potential to overcome the internal voltage while maintaining current flow.

What's the minimum and maximum Vf you've measured so far? Would you be able to say the voltage follows a nice logarithmic curve? Or does it look linear with current change?
 
I just got a PL520 build and wanted to chime in with a perspective on colour difference. I absolutely see a difference compared to 532. in fact I was very surprised. with 520 and 532 shining a dot on a white wall, 532 looks more yellow than 520. in other words 520 is more green than 532 and to my eyes brings out the yellow shift in 532. the 532 i am using is also 100mw output. of course 532 alone looks pretty green. its when i compare the two side by side. i will check out beam colour once my fog machine warms up.
 
I don't see much difference in mine compared to 532. Maybe because it's doing about 525 or so since it's driven a little hot :)
 
My 520 has a bulegreen spot while
the 532 has a yellowgreen spot. I
can easily see it now even not side-
by-side.
My wife sees the difference but can't
explain it.
HMike
 
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