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Paul A. Williams (Fed)

Paul Williams leads the High-Power Laser Applications project at the National Institute of Standards and Technology (NIST). This Project seeks to enhance the ability to measure high-power laser output parameters with the needed accuracy and ease of use appropriate for the application. This project develops measurement techniques for characterizing lasers with continuous wave powers above 1 W. These measurements include laser power, beam profile, and the interaction of the laser light with metals (plate or powder) as experienced in laser-based manufacturing (laser welding and metal additive manufacturing). High laser power measurements at NIST are increasingly being performed with radiation pressure, where the power of a laser beam is measured from the force it imparts on a mirror.

Publications

Direct Realization of the Optical Watt from Planck's Constant

Author(s)
Brian Simonds, Kyle Rogers, Sven Schulze, David Newell, Gordon Shaw, Paul A. Williams
A primary force standard is implemented to directly realize Planck's constant to the optical Watt by means of radiation pressure at the kilowatt level. The high
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Data and Software Publications

Patents (2018-Present)

Gravity-Enforced Photon Momentum Radiometer And Measuring Optical Power

NIST Inventors
Anna Vaskuri and Paul A. Williams
A gravity-enforced photon momentum radiometer incudes: a magnetic array; a diamagnetic shuttle that levitates above the magnetic array; a mirror on the diamagnetic shuttle that receives laser light and moves the diamagnetic shuttle due to the optical force; a tiltable platform for the magnetic array
image for 10,837,828

Non-attenuating Meter for Determining Optical Energy of Laser Light

NIST Inventors
Joshua Hadler , John H. Lehman , Matthew Spidell and Paul A. Williams
A non-attenuating meter determines optical energy of laser light in an absence of optical attenuation of the laser light and includes: a recipient mirror that: receives laser light that propagates in a primary propagation direction; produces profile light; transmits the profile light through the
Optical meter 1 includes ref ector 4 disposed force member 2. Ref ector 4 is conf gured to receive radiation and to communicate a pressure of the radiation to force member 2. Ref ector 4 includes substrate 5 and ref ective surface 8. Force member 2 is conf gured to be displaced in response to receiving the force comprising the pressure, and optical meter 1 is conf gured to measure a power of the radiation, an energy of the radiation, or a combination thereof based on the pressure.

Optical Meter and Use of Same

NIST Inventors
John H. Lehman and Paul A. Williams
With this technology, high-power laser beams from 1-kilowatt (kW) up to 140 kW (and beyond) can be measured accurately using optical radiation pressure. By shining a laser beam on a reflective surface and then measuring how much the surface moves in response to the light’s pressure, researchers can
A disk-shaped device is smaller than the half-dollar coin underneath it.

Smart Mirror

NIST Inventors
Alexandra (Aly) Artusio-Glimpse , John H. Lehman , Michelle Stephens , Nathan A Tomlin and Paul A. Williams
The Smart Mirror is a device that accurately measures the power of laser sources without disturbing the laser beam. This is a promising technology for accurate monitoring of output power in industrial lasers that allows power measurement during the laser’s performance of its routine operations. Such
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Created July 30, 2019, Updated April 11, 2023
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