Nishino,

2024.10.31

I characterized the GR locking loop. UGF is 580 Hz with the phase margin of ~40 degrees.

Figures:

1) Open loop transfer function (G)

6) Filters of SR560 and Moku PID controller (F)

2) G/F=AH, A: PZT actuator efficiency, H: optical gain

3-5) Settings of SR560, Moku fast, and, slow controller