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Length and Dimensional Measurements at NIST



Dennis A. Swyt


This paper reports on the past, present, and future of length and dimensional measurements at NIST. It covers the evolution of the SI unit of length through its three definitions and the evolution of NBS-NIST dimensional measurement from early linescales and gage blocks to a future of atom-based dimensional standards. Current capabilities include dimensional measurements over a range of fourteen orders of magnitude. Uncertainties of measurements on different types of materials artifacts range down to 7 x 10-8 at 1 meter and 8 picometers at 300 pm. Current work deals with a broad-range of areas of dimensional metrology. These including: large-scale coordinate systems; complex form; microform; surface finish; two-dimensional grids; optical, scanning-electron, atomic-force, and scanning-tunneling microscopies; atomic-scale displacement; and atom-based artifacts.
Journal of Research (NIST JRES) -
106 No. 1


atomic-force, dimensional, interferometry, length, measurements, microscopes, optical, scanning-electron, traceability


Swyt, D. (2001), Length and Dimensional Measurements at NIST, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed April 15, 2024)
Created February 1, 2001, Updated February 19, 2017