Member: Matteo, Eleonora, Yuefan
Today we restart the alignment from the first beginning. Firstly, with the power meter, measure the input and output of the EOM, adjust the transfer stage until almost the same power value. Then for the component, try to adjust them until the beam shine on the middle of everyone. With the tilt angle of the mirror, adjust the beam height as 76cm at both the near field and far field. Finally, we found out the transfer stage under the SHG housing is too high for present beam height.So we remove the bottom layer, got the transfer beam and the reflection beam, but the green is weak. The possible reason may be:1.Low input power 2.During the adjust process, the position of the lens may change,leading to the change of the waist position, so the input beam size of SHG crystal is too large 3.The polarization 4. The misalignment of the beam height and the crystal height. We will check all the possible reason tomorrow.