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Paul A. Williams (Fed)

Publications

Patents

image for 10,837,828

Non-attenuating Meter for Determining Optical Energy of Laser Light

NIST Inventors
John H. Lehman , Matthew Spidell and Paul A. Williams
Patent description NIST has invented a device that permits full and accurate characterization of a laser beam without attenuating the laser beam or perturbing its direction. The unique three-mirror design allows the absolute power to be measured via radiation pressure (from the force on one mirror)
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
NIST scientists have devised a radically new method of determining laser power by measuring the radiation pressure exerted by a laser beam on a reflective surface.
A disk-shaped device is smaller than the half-dollar coin underneath it.

Smart Mirror

NIST Inventors
Aly Artusio-Glimpse , John H. Lehman , Michelle Stephens , Nathan A Tomlin and Paul A. Williams
This invention measures the power of a laser beam by detecting the displacement caused by photon pressure on a mirrored surface.
Created July 30, 2019, Updated December 8, 2022