Osram PL520 info

[laserbiker]

I have been playing with the the osram green diodes recently acquired and am quite imperessed with their performance so far.
The color is a a nice shade of green. Compaired side by side to a 532nm 315m-100 laser, 532nm appears yellow-green by comparison.
I have plotted the output power versus input current on one of these lasers. It appears that the current to output is linier with no suprises.
See the attached graph.
At 50 mw output the voltage across the diode is 6.7 volts.
The beam spot is very small and has no annoying artifacts. I have not done any divergence measurements yet but I can clearly see that
it is what one would expect for a single mode diode.
The high cost $145.00 is the only drawback to this laser. I momentarily ran one at about 450 ma and it quickly turned into a very unimpressive
LED...ouch! I ground the can open on this diode and intend to microphotograph the die, once I figure out how.


I will use two of these diodes with a polarizing cube beamsplitter. The beamsplitter I received from Stan Wax Laser (Green version)works
very well in combining the beams. with 110 mw from the two diodes combined in the beamsplitter I get 99mw out.

[absolom7691]

What is the recommended current for these for a decent output but also longevity? Also, are you actively cooling them (TEC)?

[laserbiker]

The datasheet says that 200 ma is the absolute maximum current. Typical current for these at 50mw is listed at 160 ma which is very close to what
I am seeing with my diodes. For longevity I intend to run them at no more that 180ma. I have no intention of burning another one out at this time. I used the axiz style copper mounts. the diodes are a tight press fit into the 3.8mm mounts. I used arctic alumina epoxy to
fill and seal the tiny space on the diode base edges to keep dust from finding its way into the assembly. Finally they are mounted in 12mm cnc rail mounts.
They get slightly warm when running at full power this way but active cooling is not necessary.

[absolom7691]

Thanks for the info! I am trying to get one from the group buy, but I am not sure if we are going to get enough people to make it worth while. Thanks for doing some testing on them. Based on the color and the beam quality, I think I am sold. Have you tested the color against 445nm and 630nm+ for white balance? I am curious if the softer green makes any difference in the color temp of the RGB based white.

[-bart-]

Nice to see some empirical info.

Did you / can you record a voltage vs current plot ?
So we can make an output efficiency vs current plot.
This might be a good tool to determine a safe operating current.

[Laser66]

In stock in California. $145