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WTB LPM + Thank you Alaskan

GR3EN

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Thanks for looking out GR3EN! I decided in the end to go with a fog machine, and pass up on a LPM for now :)

-Alex

Well if it doesn't run up too high it might be worth a snag. I'll keep an eye on it anyway. If by some miracle it stays in the $50-$75 range maybe I'll pick it up and send it your way.
 





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Well if it doesn't run up too high it might be worth a snag. I'll keep an eye on it anyway. If by some miracle it stays in the $50-$75 range maybe I'll pick it up and send it your way.

Thanks, much appreciated GR3EN!

-Alex
 
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HAHA I know what you mean, someone here recently in another thread said that they have never seen a straight beam. I can't understand any excuse for such poor craftsmanship.

Alex, the 520nm diodes are less efficient than others and do produce more heat, it is quite possible it really does have a duty cycle of 2 minutes. It is normal for it to start dropping in power as you exceed the duty cycle, it happens on my 520nm, I can see it if I measure it on the LPM, it is common to all solid state/diode lasers, there may be some that low power with no duty cycle but probably not a 520nm.

Alan

That would make sense then, since everything else works fine. It's still crazy to me that a low powered diode needs a duty cycle. What causes this? Is it the heat sink on the PGL? The diode itself?

Thanks,
Alex
 
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Perhaps it's the KTP crystal which is so tiny it can heat up so much its temperature rises too far away from the sweet spot and thus, dims? That the problem has to do with that instead of the pump diode getting too warm?
 
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Perhaps it's the KTP crystal which is so tiny it can heat up so much its temperature rises too far away from the sweet spot and thus, dims? That the problem has to do with that instead of the pump diode getting too warm?

520 is diode based :na:

-Alex
 
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Oh, hummm... No idea why then, except one thought, how much power output does it produce? I've seen 50mw rated 520nm laser diodes, but not 5mw output ones, if it is that low. Maybe it's a higher power diode being run at lower current? Maybe it can still get hot at low output power if there isn't enough heat sink.
 
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That would make sense then, since everything else works fine. It's still crazy to me that a low powered diode needs a duty cycle. What causes this? Is it the heat sink on the PGL? The diode itself?

Thanks,
Alex

Oh, hummm... No idea why then, except one thought, how much power output does it produce? I've seen 50mw rated 520nm laser diodes, but not 5mw output ones, if it is that low. Maybe it's a higher power diode being run at lower current? Maybe it can still get hot at low output power if there isn't enough heat sink.

That's what I think, although those 50mw diodes have a higher lasing threshold that would put out more than 5mW but maybe they tested a few and found one that works.

All laser diodes have a maximum operating temperature, as you exceed it they start decreasing in power.

Alan
 
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Oh, hummm... No idea why then, except one thought, how much power output does it produce? I've seen 50mw rated 520nm laser diodes, but not 5mw output ones, if it is that low. Maybe it's a higher power diode being run at lower current? Maybe it can still get hot at low output power if there isn't enough heat sink.

It's outputting 3.68mW of 520 light :)

-Alex
 




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