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Physical Measurement Laboratory /Sensor Science Division

Dimensional Metrology Group

Realizes and disseminates the SI unit of length from micrometers to kilometers. We develop, perform and deliver measurements, standards and infrastructural technology services that promote U.S. innovation and industrial competitiveness.

Patrick Egan with the MIRE device

Better Accuracy Out of Thin (or Thick) Air
Three of the four James Webb Space Telescope Primary Mirror Backplane Support Structure fixtures on the NIST M48 Coordinate Measuring Machine.

NIST Performs Critical Measurements for James Webb Space Telescope

The Dimensional Metrology Group (DMG) provides unique high-accuracy length-based calibrations and leads documentary standards efforts that are essential to global trade, spur innovation in manufacturing, and promote adoption of innovative measuring technologies. The DMG produces over 15 % of all NIST calibrations by revenue, performing thousands of measurements for industry, academia, and government institutions each year. This includes supplying critical measurement services to the military and their primary standards laboratories, which helps ensure the reliability of assets used to keep U.S. troops safe. The DMG leads documentary standards efforts that prescribe test methods and performance specifications for advanced measuring systems used in the large-scale precision manufacturing industry, including automotive, aerospace, and excavation equipment, one of the largest net-exporters of U.S. produced manufactured goods. Hundreds of millions of dollars in metrology instruments are bought, sold, and warrantied each year using NIST-lead documentary standards, which allow manufacturers to make informed investments in new technologies that improve their efficiency, ensure product quality, and enable global trade.

CALIBRATION SERVICES, Resources, AND DOCUMENTARY STANDARDS

  • Documentary Standards
    The group’s staff actively participate in and lead the development of Documentary Standards on various Standards Developing Organizations (SDOs) by providing the necessary expertise, fundamental measurement science and advanced technologies. We engage with the following SDOs: ASME, ASTM, CIE, and ISO.
  • Resources
    The Engineering Metrology Toolbox provides tools for calculating the index of refraction of air, which is needed for interferometric length measurements, and for calculating the elastic compression of spheres and cylinders at point and line contacts.

COLLABORATION OPPORTUNITIES

The Dimensional Metrology Group welcomes opportunities to collaborate on joint research, technology, and standards development projects. The group provides multiple opportunities for students, scientists, industry, academia, and other R&D laboratories to collaborate. Specific opportunities depend on current areas of interest within the Group, but may include undergraduate research fellowship, postdoctoral fellowships, visiting scientist, and guest researchers as well as various cooperative research arrangements ranging from formal agreements, such as CRADA, Consortia, and interagency agreements, to informal collaborations. For more details, see Employment and Internship Opportunities and Collaboration Opportunities.

Projects and Programs

Laser tracker calibration in Tape Tunnel Facility

Advanced Dimensional Measurement Systems

Ongoing
New dimensional measurement technologies provide significant benefits to industry such as increasing measurement throughput, enabling new manufacturing process (such as additive manufacturing) and providing more detailed part information for manufacturing process improvement. However, before
Prototype NIST developed Next-Gen fiber probe for inspection of small critical features.

Dimensional Measurement Services

Ongoing
The Dimensional Measurement Services project promotes manufacturing innovation and U.S. industrial competitiveness by providing critical technology-enabling high accuracy dimensional measurements within an internationally accepted quality system. These measurements span the dimensional metrology
block

SI Length and Traceability

Ongoing
Laser interferometry, which measures distances in terms of light wavelength, provides the backbone of top-level length metrology in industry and science. This project develops techniques to facilitate the tie between interferometer-based length measurements and the SI definition of length (in terms

News and Updates

artifact

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
Terrestrial Laser Scanner and GPS

Helping Laser Scanners Measure Up

Scientists at the National Institute of Standards and Technology (NIST) have devised a novel, accurate, easy-to-operate, time- and labor-saving way to provide

Publications

Wavemeter calibration by frequency comb

Author(s)
Patrick Egan
Upgrades to the vacuum-wavelength calibration service at NIST are reported. The instrumentation centerpiece is an optical frequency comb tied to a GPS

Awards

Contacts

Group Leader

General Information