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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

KICS

Just for KICS!

Sensors capable of detecting individual photons of visible light have become essential for applications ranging from imaging faint galaxies to quantum computing

Events

Metrology word cloud

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
Metrology word cloud

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
Color image of SI wheel

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