A Self Stabilising Multiplexed Interferometer for On-line Surface Measurement

This paper introduces a new surface measurement method for potential online surface measurement application. It features high stability due to using near common-path configuration combined with active stabilisation. The active stabilisation is supplied by the use of a multiplexed reference interferometer and piezo-electric translator mounted mirror. The active compensation makes the system resistant to disturbance, pointing toward the possibility of on line use. The method should be of great benefit to advanced manufacturing, especially for quality and process control in precision manufacturing and on the production line. Proof-of-concept experiments have been successfully conducted by measuring the system stability over time.