Continuation of my previous post.The second AOM on the SHG sled now has light aligned so that the second pass, 1st order shift is easily accessable. Will align into a fiber and give the second filter cavity light tomorrow. Power budget is as follows:

-1st pass input to the AOM: 2.05 mW

-1st pass 1st order diffraction power: 1.7 mW

-2nd pass input to AOM: 1.7 mW

-2nd pass total power that reflects on the PBS: 1.3 mW (innefficiency from the quarter waveplate and PBS)

-2nd pass 1st order diffraction power: .6 mW

The second pass is much less efficient but this is still more power than we need to lock the cavity.

Another problem I encounter is the machine shopped metal adapter that attached the AOM to the PY005 5 axis stage is configured so that the longest side of the PY005 is along the beam propagation axis. This makes the space very limited on the SHG sled. I've found a work around, seen in the photos. Not the prettiest but it works. Long term we may want to redo these.