Aixiz 50mW labby repair

I played with brand new Aixiz 50mW labby and homemade analog driver and killed diode by mistake.

I replaced diode with another cmount 808nm diode (Thanks to Eudaimonium) but I'm not satisfied.
Focusing lens is adjusted, crystal is adjusted for best output but I cannot get more than 70-80mW of green.
Threshold is at about 400mA and to get 80mW of green I need to drive IR diode at 1300mA.

What could be problem? Is it possible that diode don't provide exactly 808nm?
Am I wrong about something?

Here are pictures...
Click on thumbnail for full size picture...






I even tried to use TEC to lower down diode temperature to change wavelength but with no success.

But here is something that I did successfully.
I replaced old expander lens with expander lens pulled out from cheap green modules.
Result is 5mm beam at aperture
Now I can combine green beam with red or blue beam and green beam will not be thiner anymore.

Sometime ago I used a 2w 808nm diode to pull a crystal extracted from a 10mw cheap module, output was very little, I tried align the crystal like mad but I noticed the crystal were darkened. I guessed that 2w were too much for that little crystal so it was burned.

It seems that you have a lot of IR showing up in your pictures... it could be that there is simply no filter, or that you have too much leaking through in the first place. That would imply an alignment issue... of course.

Nice job on the beam expander!

Do you have a university nearby that would let you use a digital spectrometer?

Crystal is aligned and IR light hits crystal first.
Can be that crystal is burned but I cannot notice that with eyes.

No, I don't believe that we have digital spectrometer in whole country

Nice work and writeup Renno! Love the pics..

I upgraded the diode in one of mine, and I know the new diode I used is 808, but the driver cannot supply enough current to higher-powered diodes.. For pump diodes 1W or higher you need to use a Flexmod instead of the stock driver..


EDIT: missed where you said you were using a homemade driver.. in that case I'm not sure what he issue could be.

I tried a 2.4W pump in one of these, with an IR filter added..

The best output I have obtained was approx 80mW. The crystal set in these
aren't the greatest..

The original pump is 1/2W, going beyond 800mW the output begins to sag.
I have seen other members report 100+mW, but the one I have could not
do it.

I also noticed severe loss between the LD and the FAC. The distance that
the lens sits from the LD is too much IMO, and the losses seem to be a result
of clipping of the LD's raw output.