Eleonora and Yuhang

After Takahashi-san glued the PZT on the new mount. We soldered the PZT to a BNC connector and replaced it with the old IR phase shifter. (attached figure 1)

The alignment to IRMC was recovered. Then we locked it and tried to see the effect of scanning IR phase shifter. We sent a sine wave to IR phase shifter from 25-125V, which is almost the same output range of our servo. Then we found IRMC transmission is modulated by almost 12% in the pitch direction. (attached figure 2)

The reason why pitched is mainly modulated is guessed as that the mirror on top of PZT is a bit heavy so it has some pitch tilt, the PZT motion creates mainly pitch misalignment. Also, the beam is tilted hitting on IR phase shifter is tilted in the pitch direction.