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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.

News and Updates

Events

5905 Volume Metrology Seminar

Mon, Apr 1 - Fri, Apr 5 2024
The 5-day OWM Volume Metrology Seminar is designed to enable metrologists to apply fundamental measurement concepts to

5856 Volume Metrology Seminar

Mon, Apr 8 - Fri, Apr 12 2024
The 5-day OWM Volume Metrology Seminar is designed to enable metrologists to apply fundamental measurement concepts to

Awards

Press Coverage

Patents

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

System And Mathod For Parameter Multiplexed Gradient Descent

NIST Inventors
Adam McCaughan , Sonia Buckley and Andrew Dienstfrey
Embodiments of the present invention relate to systems and model-free methods for perturbing neural network hardware parameters and measure the neural network response that are implemented natively within the neural network hardware and without requiring a knowledge of the internal structure of the

Mueller Matrix Ellipsometer

NIST Inventors
Thomas A. Germer
Embodiments of the present invention relate to an ellipsometer that includes a combination of a plurality of reflective devices to measure a Mueller matrix reflectance of a material in the VUV and EUV region. Ellipsometer in accordance with embodiments of the present invention relate to an

Contacts

PML Director and Deputy Director

Associate Director for Measurement Services and Associate Director

Executive Secretary