The C-CM corner mirror block uses 25.4mm (1”) or 25mm diameter Silicon mirrors coated with the Supermax
coating. As an alternative though, a λ/4 phase retarder may be used. The mirror is mounted in a ring that has
tip and tilt adjustments, which are accessible through two holes in the cover plate. The latter holds a conical
spring that bears on the mirror back to provide some restraining force.
Mirror blocks will be supplied pre-aligned to within a few arc minutes, so should not need much adjustment. If
large amounts of adjustment are actually required (about +/-2° are available), then check the alignment of the
incident beam and whether previous components are correct.
The mirror can be changed without affecting the alignment. To do this undo the two screws that hold the
cover plate in place and remove, together with the spring. Pull on the edge of the mirror to remove (or use a
piece of tape stuck to the mirror back). Replace with the new mirror and screw the cover plate on with the
spring in place. Note that the large coil of the spring fits into the recess inside the cover plate.
The mirror blocks accept the thread insert or retractable mounts. One of the latter on the input side is
recommended as this allows the mirror block to be orientated in azimuth to any angle (useful when the
corner mirror block contains a phase retarder).
Note that the clear aperture on the C-CM is 16.4mm.