I measured the power incident on REFL11 and REFL55. Steve was concerned that it is too high. If we consider this elog the incident power levels were REFL11: 30 mW and REFL55: 87 mW. (assuming efficiency of ~ 0.8 A/W @1064nm for the C30642 PD). However, currently there is a combination of Polarising BS and Half-waveplate with which we have attenuated the power incident on the REFL PDs. We now have (with the PRM misaligned):
REFL11: Power incident = 7.60 mW ; DC out = 0.330 V => efficiency = 0.87 A/W
REFL55: Power incident = 23 mW ; DC out = 0.850 V => efficiency = 0.74 A/W
and with the PRM aligned::
REFL11: DC out = 0.35 V => 8 mW is incident
REFL55: DC out = 0.975 V => 26 mW is incident
These power levels may go up further when everything is working well.
The max rated photo-current is 100mA => max power 125mW @0.8 A/W.
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