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Michelson Interferometry With 10 PM Accuracy



John R. Lawall, Ernest G. Kessler


We demonstrate a new heterodyne Michelson interferometer design for displacement measurements capable of fringe interpolation accuracy of one part in 36,000. Key to this level of accuracy are the use of two accousto-opic modulators for heterodyne frequency generation and digital signal processing demodulation electronics. We make a direct comparison of our interferometer to a commercial interferometer based on a Zeeman-stabilized laser, and show that the residual periodic errors in ours are two orders of magnitude lower than those in the commercial unit. We discuss electronically-induced optical crosstalk and optical feedback as sources of periodic error. Our new interferometer is simple, robust, and readily implemented.
Review of Scientific Instruments
No. 7


displacement measurement, heterodyne, high resolution, Michelson interferometer


Lawall, J. and Kessler, E. (2000), Michelson Interferometry With 10 PM Accuracy, Review of Scientific Instruments (Accessed May 20, 2024)


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Created July 1, 2000, Updated February 17, 2017