500mW with 2W pump diode?

[trinity_2200]

600mW with 2W pump diode?

I'm looking around for a green laser and come accross this one at O-Like. looking at the spec, it's diode is 2W, my knowledge is limited, but have read that 2 yield of a typical greenie is about 25%, so is a 2W diode capable of giving out 600 mW of green light?

http://o-like.com/b2b_cpinfo.asp?id=1023

Regards

 

[Flaminpyro]

you might want to check with Scopeguy20 and get one on a group buy...

 

[ElektroFreak]

In the absolute best conditions, green lasers are around 20% efficient. In the real world with inexpensive systems 10-15% is doing pretty good. 2W will get you 200-300 mW generally.

 

[Gryphon]

Really, for some reason i was under the impression that the efficiency was somewhere around 1W pump -> ~200mW 532nm. Guess i was a bit off

 

[trinity_2200]

In the absolute best conditions, green lasers are around 20% efficient. In the real world with inexpensive systems 10-15% is doing pretty good. 2W will get you 200-300 mW generally.

So, is it possible that the diode is overdriven to produce more than 2W of IR which yields the 600mW of green?

 

[john_lawson]

the 600 is probibly a peak reading my rpl 375 can peak at 550 somtimes
it has a 2.5 top of the line n-light pump too

 

[MarioMaster]

My Spyder I draws about an amp at 3 volts or so, indicating a pump running at around a watt of output power. Greens can certainly do better than 20% efficiency. I can't measure the actual output of the Spyder's pump diode, but at one watt that puts it at about 25% efficient.

 

[ElektroFreak]

^Very weird. That spyder should be drawing more than an amp.. ~200m from 1W is 20%, but I'd be highly impressed if it was truly that efficient. I'm guessing it's probably 1.2-1.5W of pump. That's the standard pump power for this power class. I'm not saying they can't exceed 20%, nothing is 100% rock solid when it comes to DPSS, but typically the efficiency is slightly less than that.

 

[seoguy]

I would respectively disagree - the Chinese have been doing some amazing things with crystal efficiency lately!

For example, the recent research here on the new DX modules - we are seeing efficiencies > 20% on the 100mw units, and up to / exceeding 25% on the 200mw models!

For instance, Hemlock_Mike's 200mw unit, being pumped by an over-driven 500mw 9mm 808, input current to the driver of only 610ma, metered green output of 160mw!

That would be at / likely above 25%!

Or an even better example, Bob_Bryce's recent work in pot-modding DX True 5's. One of the units had poor output due to mis-aligned crystals, and he had the foresight to meter the 808 LD directly before replacing and re-aligning the crystals. The result? 299ma in, 76mw metered green out! The best part? The 808 LD was metered at 252mw output!

That's an efficiency of over 30%!!! :gj:

And lest you argue that it was a "freak" result due to his god-like alignment skills (although I got to admit, anybody who talks about hand re-aligning DPSS crystals like it was normal maintenance like mowing the lawn or something, impressed the hell out of me! ), I would also point-out that two other identical units (whose alignment was left untouched), also set to 299ma in, were also metered at 77mw & 72mw of green!!!

So to answer the OP's question, yes, 25% is certainly possible!

But on the flip side, my own recent experience with O-Like has been less than stellar (review to follow when I get around to it). And recent metered tests of their 200mw module has indicated that some were doing noticeably less than that, with someone commenting it didn't seem to be any different than their 150mw unit!

So I would exercise extreme caution, particularly given that $800 price!

 

[lasersbee]

^Very weird. That spyder should be drawing more than an amp.. ~200m from 1W is 20%, but I'd be highly impressed if it was truly that efficient. I'm guessing it's probably 1.2-1.5W of pump. That's the standard pump power for this power class. I'm not saying they can't exceed 20%, nothing is 100% rock solid when it comes to DPSS, but typically the efficiency is slightly less than that.

This peaked my curiosity..
I just tested my 200mW SPYDER I Pro...
With a freshly charged 16850 3.7V battery and with the Laser putting
out 335mW (not completely warmed up)... the current draw was 1.13
Amps (measured before the driver).

Obviously... this doesn't prove much without knowing the exact output
of the Pump LD... but the numbers are there to play with...

Jerry

 

[ElektroFreak]

Nice numbers! I stand corrected. I know crystal quality has improved of late, but I haven't seen the numbers with my own eyes (haven't been doing hands on DPSS work for some time) so I hesitate to say for sure. If that many people are getting those kinds of numbers, that's how it is. I feel that the reason for that is the improved quality of DPMs. Aligning hybrid crystals is a breeze compared to discrete, and the crystals axes are more precisely positioned for maximum efficiency. Also, doing away with optical cement didn't hurt. There has been some pretty good amounts of power being pulled from DPMs lately, and green crystals in general while prices continue to fall. Supply and demand can be great sometimes.

Regardless of all this, I'm still ready for some green diodes. I'll be a happy man when I can build a decent RGB projector using nothing but diodes. DPSS sucks in comparison, except when you're talking about beam quality, but to have a DPSS system that is as stable and resposive as a diode-based system costs crazy money.

 

[Krutz]

as far as i know, efficiency goes up with power. as well, efficiency goes up with smaller pump-diode-size. diodes emit nonlinear too, with higher current the output rises faster?
so the most efficient setup would be an overdriven diode, for most output with tiniest die-size.. not?
of course it wouldnt survive as long..

..of yourse we could as well invest one $ for a focussing lens between the pumpdiode and the crystal..

manuel