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Physical Measurement Laboratory / Sensor Science Division

Surface and Interface Metrology Group

Projects/Programs

Displaying 1 - 12 of 12
Aperture measurement with AMM

Aperture area measurements

Ongoing
Aperture area measurements are performed at NIST’s aperture area measurement facility, which combines a precise interferometric motion stage with high-resolution optical microscopy. This non-contact method is especially well suited for the measurement of defining apertures with knife edges that are
cubic crystal

Birefringence Properties of Optical Materials (0.12 μm – 2 μm)

Ongoing
For crystals with non-cubic crystal symmetry, we make accurate measurements of the birefringence and its wavelength dispersion (0.12 μm – 15 μm) by separate index measurements of the two polarizations using the NIST's minimum deviation refractometry system. In nominally isotropic materials (cubic
Harnessing EUV capabilities for non-destructive metrology

EUV Scatterometry

Ongoing
To measure and inspect the smallest printed features on an IC chip, researchers and manufacturers use a combination of electron scanning modalities (i.e., transmission electron and scanning electron microscopies) and an optical method, scatterometry. Industrially, the most common modality for
Mechanical stylus instrument

Forensic Topography and Surface Metrology

Ongoing
Surface texture and microform Surface texture affects the functionality of many products, ranging from bearings to semiconductors and optics. Affected properties include aesthetics, friction, wear, lubrication, sealing, light scattering, and conductivity. Improvements in parameters and metrology to
Minimum Deviation Refractometer System

Index Properties of Optical Materials (0.12 μm – 15 μm)

Ongoing
The real part of the refractive index, its wavelength dispersion, and its temperature dependence are the key parameters for the design of refractive optical elements for optical systems. The demands for continually improved precision of optical instruments has driven a need for increasingly accurate
This image shows 3-dimensional topographic surface maps of the breech face and firing pin impressions left in the primer at the base of the cartridge case.

NIST Ballistics Toolmark Database

Ongoing
The database contains traditional reflectance microscopy images and three-dimensional surface topography data acquired by NIST or submitted by database users. The goal is a collection of data sets that: 1) represents the large variety of ballistic toolmarks encountered by forensic examiners, and 2)

Optical grating scatterometry

Ongoing
In the past few years, scatterometry has emerged as a method for performing linewidth and line profile metrology, especially by the semiconductor industry. The method uses a periodic target containing repetitive lines whose profile, i.e., its width, height, and shape, is to be determined. The
spatial frequency domain Mueller matrix imager

Optical Polarization Metrology

Ongoing
Electromagnetic waves are transverse. That is, besides propagating energy, they also have polarization represented by the direction of the electric field, which is constrained to lie in the plane perpendicular to the direction of propagation. Light rays can be characterized by a four-element Stokes

Optical scattering from surfaces

Ongoing
Light Scattering Ellipsometry: The polarization of scattered light can often indicate the source of that scattered light. Using Light Scattering Ellipsometry, whereby the polarization of light scattered into directions out of the plane of incidence is measured for a fixed incident polarization
skin reflectance graphs

Reflectance Measurements of Human Skin

Ongoing
Investigations of the optical properties of human skin have largely been limited to the visible part of the electromagnetic spectrum, whereas many applications require high-quality reflectance data in the near infrared and short-wave infrared. Further, the complex and dynamic nature of skin results
reflector

Spectral Reflectance and Transmittance

Ongoing
NIST serves as the nation's primary source for spectral reflectance and transmittance measurements from 250 nm to 2500 nm. Our reflectance and transmittance measurements support the measurement infrastructure of communities involved in optics, photonics, color technology, instrument manufacturing
spectrophotometric processes illustration

Spectrophotometry

Ongoing
NIST uses spectrophotometric techniques to measure the optical properties of materials for dissemination of national measurement scales to its stakeholders and advancing the development of standards, measurement methods, and modeling capabilities. The beneficiaries of these activities include the