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Physical Measurement Laboratory

Developing and delivering trusted measurements to support national needs.

Two circles of light, one green and one bluish-green, are side by side on a black background.
Tiny New Lasers Fill a Long-Standing Gap in the Rainbow of Visible-Light Colors
Table in darkened lab holds wiring and other laser electronics; a circular light source is situated above.
Major Leap for Nuclear Clock Paves Way for Ultraprecise Timekeeping

News and Updates

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A Better Balance for Tiny Liquid Masses

Scientists from the National Institute of Standards and Technology (NIST) are developing a mass balance to measure miniscule amounts of liquid with much higher

Events

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89 Fundamentals of Metrology

Mon, Jan 27 - Fri, Jan 31 2025
Course Description The 5-day Fundamentals of Metrology seminar is an intensive course that introduces participants to
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88 Volume Metrology Seminar

Mon, Feb 3 - Fri, Feb 7 2025
Course Description The 5-day OWM Volume Metrology Seminar is designed to enable metrologists to apply fundamental
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86 Metric System Education Resources

Thu, Feb 13 2025, 5:00 - 6:30pm EST
The International System of Units (SI), commonly known as the metric system, is easy to use and learn when taught using

Awards

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Press Coverage

Patents

Continuous-Wave Laser Source And Making A Continuous-Wave Laser Source

NIST Inventors
Scott Papp
A method of designing a continuous-wave laser source having a target output wavelength and an input laser with a wavelength different from the target output wavelength includes the steps of receiving the target output wavelength, and subordinate properties of the laser source; determining a

Sound Pressure Metrology Instrument And Determining Sound Pressure From Index Of Refraction

NIST Inventors
Richard A. Allen , Randall P Wagner , Benjamin Reschovsky and Akobuije Chijioke
A sound pressure metrology instrument determines sound pressure from index of refraction and includes: a light source that produces source light; the optical cavity that: receives an acoustic field from the sound source; receives the source light from the light source; produces acoustic-modified

Contacts

PML Director and Deputy Director

Associate Director for Measurement Services and Associate Director

Executive Secretary