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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

Optical medical imaging

The Optical Medical Imaging project was established to advance the application of optical imaging in surgical, clinical, and medical practices. Our goal is to

Vision science

The Vision Science program was established to develop new photometric and colorimetric standards based on vision science to facilitate development of emerging

Molecular spectroscopy

The molecular spectroscopy sub-group carries out vibrational and rotational spectroscopic analyses on experimental data obtained primarily in the infrared (IR),

Diffraction effects in radiometry

We want to quantify the breakdown of geometrical optics when computing the throughput of optical systems for the purpose of calculating "diffraction corrections

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

Reference transmittance densiometer

The Reference Transmission Densitometer (RTD) is the national reference instrument for standard diffuse visual transmittance density measurements for x-ray

Contacts

Group Leader

Office Manager