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Published on: September 22, 2017
Analysis of a scanning pentaprism system for measurements of large flat mirrors
Julius Yellowhair1, James H Burge
1Sandia National Laboratories, 1515 Eubank SE, Albuquerque, NM 87123, USA. jeyello@sandia.gov
Abstract:
The optical surface of a large optical flat can be measured using an autocollimator and scanning pentaprism system. The autocollimator measures the slope difference between a point on the mirror and a reference point. Such a system was built and previously operated at the University of Arizona. We discuss refinements that were made to the hardware, the alignment procedure, and the error analysis. The improved system was demonstrated with a 1.6 m flat mirror, which was measured to be flat to 12 nm rms. The uncertainty in the measurement is only 9 nm rms.
