Two viewport windows on the gate valve (GVs) between the MCF and IFI chambers are changed with new glasses with AR-coated as planned.

http://gwclio.icrr.u-tokyo.ac.jp/lcgtsubgroup/inoutoptics/2015/07/mcf-ifigate-valveviewport-window.html

With this work, AOS has finished to change all the windows on the exsiting GVs in KAGRA to the AR-coated ones (10 pieces of windows in total).

This is a small milestone for AOS.

The details of the AR-coated windows are fonud in

http://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/private/DocDB/ShowDocument?docid=2926