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In support of defense programs in remote sensing, NIST maintains the scale for infrared radiant flux by using an Absolute Cryogenic radiometer (ACR) in a low
Electron, ion and photon-based microanalysis methods, instrumentation and protocols are developed to advance measurement science towards the elemental and
NIST's versatile wind tunnel is used to calibrate customers' airspeed sensors and to conduct research on the design of novel anemometers, the responses of
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
The goal of the BIB-Trap Detector project is to develop a detector composed of solid-state devices that can be used as a reference detector for calibrations in
To compare the calibration capabilities for the spectral responsivity in the vacuum-ultraviolet spectral region between 135 nm and 250 nm, PTB and NIST agreed
ROSI (Robotic Optical Scattering Instrument) is a new facility for measuring reflectance and scattering of materials in the ultraviolet to short-wave infrared
Calibrations of the The Extreme ultraviolet/X-ray Irradiance Sensor (EXIS), which will be installed on the Geostationary Operations Environment Satellite R
The National Institute of Standards and Technology (NIST) is working to advance measurement capabilities needed to study the world’s climates. Climate Science
Every four years, the Committee on Data for Science and Technology (CODATA) issues recommended values of the fundamental physical constants. The values are
We are building a cold-atom based sensor program that represents a new approach to metrology—to establish a set of chip-scale tools that enable real-world use
We are developing instrumentation, standards artifacts, and measurement protocols to characterize appearance attributes including color, texture, and gloss
Optical systems that operate at wavelengths in the ultraviolet (UV) and extreme-ultraviolet (EUV) are susceptible to degradation by a number of different
High performance optical radiometers with selected optical detectors are being designed, characterized, and calibrated in the Optical Radiation Group for the
We want to quantify the breakdown of geometrical optics when computing the throughput of optical systems for the purpose of calculating "diffraction corrections
The goal of this project is to extend and improve the measurements of the key climate record of the long-term balance between Earth absorption of solar energy
This project is developing zone plate technology to enable compact solar radiometers for observing the solar 30.4-nm emission from ionized helium in the
The extreme ultraviolet detector (EUVD) calibration service disseminates the U.S. national scale of detector responsivity in the wavelength range from 5 nm to
In the vacuum ultraviolet and extreme ultraviolet (EUV), the indices of refraction of all materials become complex: N = n + ik , or N = 1- d + ik . Here, n is
To support comb-based measurements outside the metrology laboratory, we develop high performance, robust frequency combs based on fiber-optic technology.
Optical frequency conversion, in which the color of light is changed, is a process that has numerous applications in physics and technology. For example, green