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Optical Radiation Group

The Optical Radiation Group maintains, improves, and disseminates the national scales for the candela (SI unit), spectral responsivity, reflectance, transmission, color, and appearance.

Our staff participates in national and international committees and intercomparisons to ensure the acceptance of US radiometric, photometric, colormetric, and spectrophotometric standards and measurements. We also develop protocols for the calibration and validation of optical remote sensing instruments, perform long-term research, and maintain the infrastructure necessary to ensure the advancement of radiometry, photometry, colorimetry, and spectrophotometry measurement technology.

News and Updates

Projects and Programs

Photometry

The purpose of photometry is to measure light in a way that takes the sensitivity of human visual system into account. While radiometry measures light in all

Detector metrology

High performance optical radiometers with selected optical detectors are being designed, characterized, and calibrated in the Optical Radiation Group for the

Publications

A review of protocols for Fiducial Reference Measurements of water-leaving radiance for validation of satellite remote sensing data over water

Author(s)
Kevin Ruddick, Emmanuel Boss, Alexandre Castagna, Robert Frouin, Alex Gilerson, Martin Hieronymi, Bettye C. Johnson, Joel Kuusk, Zhongping Lee, Michael Ondrusek, Viktor Vabson, Riho Vendt, Kenneth Voss, Giuseppe Zibordi
This paper reviews the state of the art of protocols for measurement of water-leaving radiance in the context of Fiducial Reference Measurements (FRM) of water

A review of protocols for Fiducial Reference Measurements of downwelling irradiance for validation of satellite remote sensing data over water

Author(s)
Kevin Ruddick, Andrew Banks, Emmanuel Boss, Alexandre Castagna, Robert Frouin, Martin Hieronymi, Cedric Jamet, Bettye C. Johnson, Zhongping Lee, Michael Ondrusek, Viktor Vabson, Riho Vendt, Kenneth Voss, Giuseppe Zibordi
This paper reviews the state of the art of protocols for measurement of downwelling irradiance in the context of Fiducial Reference Measurements (FRM) of water

Tools and Instruments

Spectral comparator facilities

Visible to near-infrared spectral comparator facility (Vis/NIR SCF)The Vis/NIR SCF is a monochromator-based system that typically measures the spectral power

Reference 0:45 reflectometer

The primary purpose of the 0:45 reflectometer is to disseminate color standards to the color and appearance community. The instrument was designed to provide

NIST Gonio-spectroradiometer

The NIST gonio-spectroradiometer is used to measure total spectral radiant flux (TSRF) of incandescent lamps. The instrument consists of a 3-axis scanning

Contacts

Group Leader

Office Manager