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Physical Measurement Laboratory

Developing and delivering trusted measurements to support national needs.

News and Updates

BIPM 150th Anniversary Standout Poster

World Metrology Day (20 May 2025) marked the sesquicentennial, or 150th anniversary, of the Meter Convention. NIST and the Office of Weights and Measures (OWM)

Events

Awards

Press Coverage

Get quantum-generated random number for free

EE News Europe
Researchers at ICFO in Barcelona, Spain, worked with spinout QuSide to developed a fast quantum random number generators that is being used the US National

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

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