Preparations for laser power increase
In autumn 2012 we opened the input modecleaner vacuum chambers, in order to prepare them for an increase in laser power.
We have exchanged four mirrors and replaced some optical modulators in the vacuum system. Finally, we exchanged a lens to improve the mode matching of the laser beam leaving the modecleaners towards the main interferometer.
After the work was completed, the total power throughput of the modecleaners was increased from 45% to 75%, and the modematching had improved from 80% to more than 90%.