Wave plate moving on the 2 TCS benches

This morning we (E. Campagna and I) went to the TCS bench in order to solve the problem experienced yesterday night on the minum power of the TCS.
It seemed that the pick-up beam splitters, inserted for the central heating, make the polarization of the transmitted beam elliptical, so that the rotation of the wave-plate is not completely effective as before.
So we tried to move the wave-plates before the beam splitters.
Actually this reduced the minumum transmitted power to 0.15 W for the NI and 0.25 for the WI. We also recalibrate (see attached fig) the WI transmitted power (power of the annulus impinging on the WI TM) versus the voltage acquired by the ADC.

The new conversion equation is:
PWI(W)=1.29+69.6*(V1:Pr_TCS..WI_Power_MEAN)
These values were updated to the TCS launch pad.

We took the occasion to look at the shape of the annulus and we realign slightly the WI in order to have a more simmetrical shape.