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Physical Measurement Laboratory

PML is a world leader in the science of measurement. We determine the definitive methods for nearly every kind of measurement employed in commerce and research, provide NIST-traceable calibrations, and disseminate standards and best practices throughout the nation. At the same time, PML works continuously at the outermost frontiers of metrology, devising tools and techniques to meet the ever-changing demands of American industry and science.

SI Redefinition

Outer circle has one wedge for each of the 7 SI units (kilogram, meter, second, ampere, kelvin, mole, and candela) and the inner circle has wedges for the 7 important constants.
Credit: BIPM

NIST is producing a series of special reports on the worldwide consensus plan to redefine four of the seven basic units of measurement in the International System of Units in terms of invariants of nature.

Explore these stories, as they become available, on the SI Redefinition Portal.

News and Updates

Events

5709 Software Verification and Validation

Thu, Jun 10 2021, 12:00pm - Thu, Jun 24 2021, 2:00pm MDT
Session I (June 10, 2021) and Session II (June 24, 2021) These two 2-hour sessions on Software Verification and

5719 Fundamentals of Metrology - CANCELED

Mon, Jun 21 2021, 6:00am - Fri, Jun 25 2021, 3:30pm MDT
The NIST Gaithersburg campus is currently in Phase 1 of reopening and is closed to visitors. Do not make any travel

Industry Impacts

Fare Standards for Rideshare Services

To calculate fares, app-based ride services such as Lyft and Uber don’t use traditional taxi meters, but instead combine data from GPS and cellular networks to

Nanolithography Design Tools

Accurate production of nanoscale features on semiconductor chips is essential to their performance, but typical design tools cater to the dominance of straight

High-Power Lasers for Manufacturing 

Measuring the intensity of high-power lasers used by manufacturers for precision cutting and welding can be difficult due to large instrumentation challenges

Brain Mapping Technologies

Magnetic signals produced by electrical currents in the brain can be used to map brain processes and help in the diagnosis and treatment of disease

Awards

Press Coverage

Patents

A timeline of long distance communication techniques

Communication Linker for Communication Linking

NIST Inventors
Sergey Polyakov and Ivan Burenkov
Patent Description The US has the leading optical communication industry and one of the largest telecommunication markets. Our invention directly improves the underlying technology of the telecommunication infrastructure. Quantum Coherent Frequency Shift Keying (CFSK) receiver is a device that

Optical Phantom for Producing a Time-Resolved Diffuse Reflectance Spectrum

NIST Inventors
Jeeseong C. Hwang
Patent Description Physikalisch-Technische Bundesanstalt (PTB) and NIST jointly developed a concept for a waveform synthesizer which can generate a controlled waveform with several picosecond (ps) time resolution. In a light-diffusing material, characteristics of the time-of-flight distribution (e.g
Line drawing of the thermal impedance amplifier

Thermal Impedance Amplifier

NIST Inventors
Adam McCaughan, Varun Verma, Sonia Buckley and Sae Woo Nam
Patent Description Presently, superconducting electronics are being applied to areas such as computational backends for future quantum processors, high-performance supercomputing, and ultrafast digital signal processing. In all of these areas, data must be communicated between the superconducting
This image of a chart titled "How does it work" that describes the optomechanical reference.

Optomechanical Reference

NIST Inventors
Gordon A. Shaw and Jacob Taylor
A mechanical sensor incorporating an optical cavity is used to provide a mass and/or force reference from a known or characterized circulating optical power in the optical cavity. The radiation pressure force in the optical cavity is used to actuate the mechanical sensor. The optical cavity in put

Contacts

PML Director and PML Deputy Director

Associate Director for Measurement Services and Associate Director

Executive Secretaries to Director Kushmerick and Deputy Director Williams