Slit assembly Positioning Collimators

Grating cell

This is positioned between the two collimators. The axis of rotation should be 100.0mm behind the rear of C . To get it into this position, use the template brought from RGOC, remove C , square on to collimator axis laser (having installed the ISIS dummy grating in the cell), replace C , and check the separation, and squaring on. Clamp the baseplate securely to the optical bench, and lock all kinematic mounts. The grating encoder should read 0 milledgrees when the grating is squared on to the collimator axis laser.