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Radiometric and photometric measurements require defining apertures. The accuracy to which these measurements can be accomplished requires minimization of the
Spectroradiometers are widely used for acquiring colorimetric, photometric, and radiometric quantities with a single measurement for a variety of applications
High performance optical radiometers with selected optical detectors are being designed, characterized, and calibrated in the Optical Radiation Group for the
Until recently calibrations of tristimulus colorimeters were performed against lamp standards. However, the uncertainty of these source-based calibrations
NIST cooperates with the three services (Air Force, Navy, and Army) to realize a uniform night vision goggle (NVG) calibration system with low measurement
Ocean color radiometry provides essential information about phytoplankton concentration and dissolved organic matter, and hence about primary productivity
Radiometric, radiance temperature, photometric, and color scales have been realized based on the spectral responsivity of standard detectors and radiometers
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
Photographs, or optical light images, are spatial records of light reflected or emitted from objects. Thus, they are prospective light measurements. In many
The radiation sensitivity of a Thermoluminescent Dosimeter (TLD) is defined as dosimeter light output per dose unit. TLD light output depends not only on the
Calibration standards for radiation thermometry are disseminated in the form of radiation thermometers, tungsten strip lamps and blackbodies. These disseminated
The Remote Sensing Laboratory comprises spectral radiance and irradiance sources, filter and hyperspectral radiometers, and an environmental chamber that are
With the rise of new, energy-efficient solid-state lighting (SSL) systems has come the need for new performance metrics and measurement methods to address their
NIST provides calibration of the spectral responsivity and spatial uniformity of photodetectors for use in industrial and government labs. These calibrations
Calibration standards for spectral radiance and spectral irradiance are disseminated in the form of transfer lamps and integrating sphere sources. These
To decrease the large measurement-uncertainty gap between cryogenic radiometer measurements (such as those made by the NIST Primary optical watt radiometer) and
The Vision Science program was established to develop new photometric and colorimetric standards based on vision science to facilitate development of emerging