[Enomoto, Nakano]

We adjusted the gouy phase of the injection IR-beam into the QPDs. Firstly, we adjusted the position of the second lens (RMSL2) so that the beam position located 1 m from the RST2. Then, we measured the beam profile. The attached figure shows the beam size and the gouy phase. The fitting seems not good around the beam waist. This is because the beam was too small compared to the resolution of the beam profiler. The Rayleigh range of this beam calculated from the fitting is 89 mm. Therefore, the QPDs was put at the position of +/- 89 mm from the beam waist position z = 960.

At the same time, we moved the camera to the position near the beam waist. The attached picture shows the image of the new TMS IR camera.