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Patrick Egan (Fed)

Patrick began at NIST in 2006 as an NRC-NIST postdoc.  At the time, his focus was on the development of an optical frequency comb metrology system for the calibration of vacuum-wavelength.  In 2008 he began to investigate highly precise measurements of the refractive index of air using a Fabry-Perot cavity-based refractometer.  The work culminated in one of the most accurate measurements of the refractive index of nitrogen and argon at 633 nm, and laid the groundwork for what developed into the 2012 Innovation in Measurement Science (IMS) project entitled "Reinventing pressure, temperature, and length".  Since 2012 he has been part of the team attempting to use highly accurate measurements of gas refractivity to realize the pascal.  As of 2017 the project is ongoing.

Since 2015 Patrick has been a staff member of the Dimensional Metrology Group, and leader of the SI Length and Traceability project.


Quantum for Pressure

Jay H. Hendricks, Patrick F. Egan, Jacob E. Ricker, Jack A. Stone Jr., Kevin O. Douglass, Gregory F. Strouse
A team of NIST scientists is working to fundamentally change the way that the unit of pressure is realized and disseminated, an effort that will lead to the


Deformometer for Determining Deformation of an Optical Cavity Optic

NIST Inventors
Zeeshan Ahmed , Kevin O Douglass , Stephen Eckel , Patrick Egan and Jay H. Hendricks
Patent Description NIST has developed a device that uses multiple wavelengths (colors) of light and/or multiple species of gas to independently measure the distortions imposed on an optical cavity, cell, or other optical element that holds gas due to the forces applied by the gas. The device
Created October 23, 2018, Updated June 15, 2021