2016 November: Gluing and mounting of the spectrograph optics
The SPIRou spectrograph optics were integrated in their respective mounts at IRAP/OMP
Following the integration and metrology of the off-axis parabola at LAM (Marseille) last summer, remaining spectrograph optics, i.e., the échelle grating, the folding mirror and the 3 prisms of the double-pass cross-disperser were glued and installed in their respective mount.
Before shipping to IRAP/OMP, two sets of Zerodur pucks and Invar / aluminum flexures were bonded to each optical component at NRC-H, with one on the top and one on the bottom. These sets ensure the spectrograph optics can be correctly positioned, without being stressed by the contracting mount during cooling phases. The grating being hold face down rather than vertically, a third set of puck and flexure (bonded to the back side) is used to secure it to its mount.
As for the parabola mount, NRC-H carried out the thermal and mechanical designs of these custom mounts. The mounting phase consists in attaching the optical components to their mounts using reference tools as calibrated shims and micrometric devices. All optics were installed in their mounts at their nominal positions within specifications.
Bonding was performed by Vlad Reshetov and John Pazder, at NRC-H (Victoria, Canada). Optics were mounted in the SPIRou clean room at IRAP/OMP (Toulouse) in collaboration with Vlad Reshetov, Les Saddlemyer (NRC-H), Greg Barrick (CFHT, Hawaï) and the IRAP/OMP team.
