NI power calibration

Since it was noticed that, starting from a certain time, the power read by the power-meter of the NI TCS gives negative values in the region of the minimum transmitted power (see entry TCS NI power calibration), we repeated the calibration. Results are plotted in the figure.
The new calibration relation is: Pni(W)=5.247*Pr_TCS_NI_Mean-0.054
Before (see CH beam splitter replacement) it was: Pni(W)=5.134*Pr_TCS_NI_Mean-0.107
It seems that the main difference comes from the offset, as expected.

Since the power meter is set to a maximum range of 300mW, we report here also the Ring power as a function of the waveplate angle.
Angle(deg) P(W)
-96.0 0.04
-94.0 0.18
-92.0 0.58
-90.0 0.97
-88.0 1.55
-85.0 2.57
-80.0 4.80
-75.0 7.38
-72.0 8.95
-70.0 9.95
-68.0 10.92 %From this point the power meter is overloaded
-66.0 11.87
-64.0 12.66
-62.0 13.40
-60.0 13.98
-58.0 14.49
-56.0 14.83
-54.0 15.05
-52.0 15.14
-50.0 15.07
Minimum power is about 40mW, maximum is around 15W.