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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


5854 Mass Metrology Seminar

Mon, Feb 26 - Fri, Mar 8 2024
The Mass Metrology Seminar is a two-week, "hands-on" seminar. It incorporates approximately 30 percent lectures and 70

5893 Basic Uncertainty Concepts

Thu, Feb 29 2024, 2:00 - 4:00pm EST
This 2-hour webinar provides a very basic introduction to uncertainty calculations and reporting using the 8-step

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


Press Coverage

Scientists unveil new 'heart-on-a-chip'

Live Science
So-called heart-on-a-chip systems may enable scientists to evaluate the safety and efficacy of new drugs more accurately than they can with animal tests.


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

Thin Film Magnetic Magnitude Sensor

NIST Inventors
David Gundlach , Emily Bittle and Sebastian Engmann
A novel magnetic field sensor (MFS) may be created with an organic light emitting diode (OLED) made from an organic semiconductor material and an organic photodetector (OPD) built directly on top (or below) of the OLED, wherein one layer is made from a magnetically isotropic material, and which


PML Director and Deputy Director

Associate Director for Measurement Services and Associate Director

Executive Secretary