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2.6 Post-Slit Viewer

The post-slit viewer (figure 1 ) allows one to view from below the light coming through the slit. For this purpose a flat mirror is rotated into the beam manually or via computer. This viewer is useful for checking the light path for obstructions and for doing knife-edge focusing using the slit and a star. The pickoff mirror must be out of the beam when not in use.

There is normally no TV available on this viewer.
Fri June 9 08:00:00 MST 1995