[Nakano,Kitazawa]

We measured relative intensity noise at laser power = 20W (laser current = 33A).
This laser power was decided not to saturate PD output.
At that time ,In-loop sensor output voltage is 8.04V(22mW),Out-of-loop sensor output voltage is 10.0V(28mW).

The figure shows relative intensity noise about free-run ,In-loop and Out-of-loop. 
The results of the noise budget are also shown in the figure.I suspect that the noise limiting the low-frequency side of out-of-loop is a sensing noise.