50mW tunable 532nm + power supply = 65$

[dar303]

I bought one of these from aixiz and hooked it up to a D4drive.

I tested it at 336 mA, it produced about 55mW at this current.
When I turned it up I got 92mW at 445 mA, with currents higher than that the output started to slowly sink but it peaked at about 105mW a few times.

I haven't used it for more than 30 minutes so I know nothing of how well it can take this kind of treatment.

[buffo]

I tested it at 336 mA, it produced about 55mW at this current.
When I turned it up I got 92mW at 445 mA,

Those are pretty decent numbers. My most efficient DPSS laser puts out 100 mw of green with 650 ma of drive current. So 92 mw at only 445 ma current is pretty darned good.

I wouldn't run it at much over 50-60 mw though. Pushing it to 90 mw will probably shorten the life of the pump diode.

Adam

[carmangary]

Yea, those numbers are better than mine for the same model. Takes me about 550ma for 50mw. I wonder why the big difference?

[buffo]

eh - lots of variables... Alignment, efficiency of the optics, efficiency of the KTP, quality of the coatings, thermal issues, the phase of the moon... (OK, maybe not that last one.) But yeah, every once in a while everything comes together just right and you get really efficient numbers. (The same thing happens with laser pointers. Every once in a great while you'll find a really hot one that can be tweaked to 100 mw or more, even though most of them will die quickly if you push them past 40 mw.)

Still, it's rare to see such good numbers in a cheap DPSS module. Simon, consider yourself lucky!

Adam

[dar303]

Are you measuring the current off the original driver or between the diode and the driver?
I use d4drive and measure the current (acutally voltage drop) over a shunt resistor on the power pin of the driver transistor.
I think the original driver wastes a lot of current so try measuring directly on the diode leads.

Yea, those numbers are better than mine for the same model. Takes me about 550ma for 50mw. I wonder why the big difference?

[carmangary]

I'm measuring the diode current.

[carmangary]

I just hooked up my new green 50mw module for testing. It's putting out 100mw. I'm wondering if I should turn down the power a little.

[dar303]

No, keep it up there and see if it lives...so I don't have to!

[carmangary]

I'd like to but I want it to last a long time. I'll probably back it down to around 75mw at least.

I did notice the other day that it was mode hopping. It doesn't always do it but sometimes it will jump to having 2 beams side my side. I am not sure why it does that. To be honest, I really have no idea how lasers work.