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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


Characterization and Absolute Calibration of an AERONET-OC Radiometer

B. Carol Johnson, Giuseppe Zibordi, Steven W. Brown, Michael Feinholz, Mikhail Sorokin, Ilya Slutsker, John T. Woodward IV, Howard Yoon
The Ocean Color component of the global Aerosol Robotic Network (AERONET-OC) utilizes CE-318 sun photometers modified for above-water radiometry from fixed


Image of devices on a table

Optical Parametric Oscillator

NIST Inventors
John T. Woodward IV, and
Patent Description This invention is a light source that provides high-power (1W to 5W), narrow line-width (<1 nm), quasi-continuous wave (80 MHz) light that can be tuned in wavelength from 340 nm to 2300 nm. See figure below. The light source is fully automated, solid state, and fits on a
Created May 31, 2018, Updated June 15, 2021