Last Friday and yesterday we did the alignment in the PR chamber and also the beam path from PR chamber to BS chamber. The mirror is still in almost the same position as the picture I showed last time. We adjust the green and infrared beam surpassed until the BS chamber.
Then install the reflect mirror just after the dichoric mirror temporarily to adjust the reflect beam of infrared to goes the position it should be at the optical bench as the new optical scheme.
We also check the power loss of the beam goes through the Faraday and comes back to the optical bench, it is about 6% and 10%.
The we put back the middle part of the PR chamber, since then the beam will first go through the thick window mirror, if it is not exactly perpendicular to the mirror, there is at least some shift of the beam. And also it seems the mirror also is a wedge mirror, now the beam in the chamber moves a lot. One of the idea is to move the last mirror before the beam goes into the chamber on the bench, but then there is the risk that the beam will be move out from the mirror. Matteo will work on this in these days.
And on Friday, we plan to measure the green beam, and do some calculation to decided the lens we are to use, and we should buy them, since now in the lab the shortest focus length is 100mm.