To pick off adequate laser power for our PD QE enhancement experiment, the first HWP in front of the laser was rotated.
The inititial angle of the first HWP was 48 degree.
For measuring the laser power, some optics were aligned as shown in the following figure using a CCD camera.
In this figure, the beam dump #1 is placed for dummping the laser for the other expetiment that is made on the same optical bench as the PD QE experiment, and the Irises are placed for dumping unnecessary light.
I plan to place HWPs and PBSs additionally and to measure the polarization and the laser power at the beginning of next week.