Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

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.


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
A metal cube (RPPM) mounted on a metal surface has round holes cut in each side.

Optical Power Meter

NIST Inventors
John H. Lehman and Paul A. Williams
An optical meter includes a force member to receive a force and a reflector disposed on the force member to receive radiation and to communicate a pressure of the radiation to the force member. The reflector includes a reflective surface, and the force member is configured to be displaced in
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
Radiation pressure is a force that results when light reflects from a mirror. By measuring the force on a mirror, the power in a laser beam can be assessed. We have invented a miniaturized mirrored force sensor that combines several key elements to make a sensor that is smaller, faster, more
Created July 30, 2019, Updated April 11, 2023