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John T. Woodward IV (Fed)

Dr. Woodward is a research physicist in the Spectral Irradiance and Radiance Calibrations using Uniform Sources (SIRCUS) laboratory. His primary research involves making radiometric measurements used to improve the calibration of Earth remote sensing instruments. He is a co-PI on the Airborne Lunar Spectral Irradiance (Air-LUSI) project to make high-accuracy spectral irradiance measurements of the moon from a high-altitude ER-2 aircraft. He has participated in the calibration of several Earth Observing Satellite sensors. He is also involved in research to measure the absolute spectral flux of standard stars and to improve radiometric temperature measurements.

Research projects

Lunar Spectral Irradiance (LUSI)

Spectral irradiance and radiance responsivity calibrations using uniform sources (SIRCUS)

NIST Stars

Telescope calibration facility

Selected Publications

Supercontinuum Sources for Metrology

John T. Woodward IV, Allan W. Smith, Colleen A. Jenkins, Chungsan Lin, Steven W. Brown, Keith R. Lykke
Supercontinuum (SC) sources are novel laser-based sources that generate a broad, white-light continuum in single mode photonic crystal fibers. Currently, up to


Patents (2018-Present)

Image of devices on a table

Optical Parametric Oscillator

NIST Inventors
John T. Woodward IV
An optical parametric oscillator produces optical parametric light and includes a frequency splitter to produce signal light and idler light; a wavelength selector to select a wavelength of the signal light and to produce optical parametric light from the selected wavelength of the signal light; and
Created May 31, 2018, Updated December 8, 2022