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Electron, ion and photon-based microanalysis methods, instrumentation and protocols are developed to advance measurement science towards the elemental and
Atmospheric aerosol particles often have compositions and shapes that cannot be described as a single material phase within a simplified geometric form such as
The National Institute of Standards and Technology operates two spectral comparator facilities, both of which are used to provide detector calibrations from the
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
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
Nano and atomic scale theory of the electronic, optical and mechanical properties of ultrasmall structures, such as semiconductor quantum dots and dopants in Si
Until recently calibrations of tristimulus colorimeters were performed against lamp standards. However, the uncertainty of these source-based calibrations
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.
We have constructed portable frequency combs that have provided in situ calibration of astronomical spectrographs, to aid in the search for exo-planets.
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
Dual-comb spectroscopy is a technique that allows one to exploit the coherence, accuracy, and resolution of frequency combs for precision molecular spectroscopy
This project provides new measurement methods, property data and simulations for areas critical to US manufacturing, describing the mechanisms responsible for