Unbeknownst to me, Ed had already performed diagnostic breadboard scans of the laser. However since I
had already started, I might as well finish.
First off, the high power oscillator. No problems observed with the scans except when it came to
doing the mode scan, when the following error message(s) appeared:
[======================= ] 45% 5m29s / 10m00sNo significant mode found! The roundtrip gouy phase might be wrong.
[======================== ] 48% 5m15s / 10m00sNo significant mode found! The roundtrip gouy phase might be wrong.
[======================== ] 48% 5m13s / 10m00sNo significant mode found! The roundtrip gouy phase might be wrong.
[======================== ] 48% 5m09s / 10m00sNo significant mode found! The roundtrip gouy phase might be wrong.
[========================= ] 50% 5m01s / 10m00sNo significant mode found! The roundtrip gouy phase might be wrong.
[========================= ] 50% 4m57s / 10m00sNo significant mode found! The roundtrip gouy phase might be wrong.
[============================== ] 60% 4m01s / 10m00sNo significant mode found! The roundtrip gouy phase might be wrong.
[============================== ] 60% 3m59s / 10m00sNo significant mode found! The roundtrip gouy phase might be wrong.
This is the first time I've seen such an error message. One could also argue what about the first 44% of the time and the last 39% of the
time. Not sure what happened there.
The relative power noise measurements looks okay but is a factor of ~2 higher than the reference traces across the board.
The frequency noise scan shows a problem for frequencies lower than ~60 Hz. Some kind of oscillation or settling time issues. With
that comparison with the reference traces probably does not make sense.
The beam pointing measurement looks out of whack to me. Not sure why but 12 orders of magnitude better than the reference traces
is obviously too good to be true.
The mode scan says 6.6% in higher order modes. There is a note of caution about this value though because of the error messages that
appeared during the scan.
Measurement of the inner loop power stabilisation: the out of loop relative power noise is ~10 times higher for frequencies lower than
40 Hz and ~4 times higher at 100 Hz. Although at this point I do not recall if the reference traces are for the high power oscillator or
the front end laser (probably the latter methinks).