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Dimensional metrology

News and Updates

Back to the Future: Gear Edition

As mechanical objects, gears have been around for so long that people may take them for granted. But gears are sophisticated parts that play a vital role in

Projects and Programs

AM Machine and Process Qualification

Ongoing
Machines and processes used to produce critical components for defense, aerospace, and medical applications must first be formally qualified. While

SI Length and Traceability

Ongoing
To enable our highest accuracy calibrations and NIST advanced research efforts, we maintain and develop methods to provide traceability to the meter via laser

Publications

Shrinks When It's Colder

Author(s)
Patrick Egan
Thermal expansion can be a leading cause of uncertainty in length metrology. A cell-based refractometer has been designed at NIST which targets 10^-6} relative

D-to-A_eff converter

Author(s)
Patrick Egan, Eric S. Stanfield, John R. Stoup
Recent developments in diameter metrology at NIST have enabled the dimensional characterization of piston-cylinder assemblies (PCA) with unprecedented precision

Tools and Instruments

Precision Imaging Facility

The Precision Imaging Facility (PIF) is a cooperative research facility at the National Institute of Standards and Technology (NIST) dedicated to the