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Surface and Interface Metrology Group

Develops and disseminates measurement methods and documentary and artifact standards for the characterization of the optical and topographical properties of surfaces, particularly surfaces and surface finishes important in optical instrumentation, forensics, and consumer products.

The group mission is to maintain the nation scales for the fundamentals optical and topographical properties of surfaces and to advance the state of the art of these measurements. The group works closely with leading U.S. optics manufacturers and metrology instrument manufacturers, government and academic research institutes to provide new measurement solutions for critical needs. We lead national and international documentary standard efforts that prescribe test methods that ensure product quality and enables global trade. Efforts are undertaken in close collaboration with academic researchers, government agencies, and industry, including stakeholders within the aerospace, forensics, defense, semiconductor, precision manufacturing, and remote-sensing communities. The topographical surface efforts realizes and disseminates the SI unit of length for measurements of nanostructure, roughness, waviness, and form for surfaces with vertical dimensions ranging from nanometers to micrometers and horizontal dimensions ranging from micrometers to hundreds of millimeters. Optical properties measurements include index of refraction, surface color and appearance, diffuse and regular transmittance, and diffuse, regular, and angle-resolved surface reflectance.

Projects and Programs

Reflectance Measurements of Human Skin

The purpose of this human subjects study is to collect high-quality measurements of the reflectance spectrum of human skin and assess the variability across the

Color and appearance

We are developing instrumentation, standards artifacts, and measurement protocols to characterize appearance attributes including color, texture, and gloss

NIST Ballistics Toolmark Database

The NIST Ballistics Toolmark Research Database is an open-access research database of bullet and cartridge case toolmark data. This database will: foster the

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 and


Modeled integrated scatter tool (MIST)

The MIST program has been developed to provide users with a general application to model an integrated scattering system. The program performs an integration of


News and Updates


Firearm examination: Examiner judgments and computer-based comparisons

Erwin J. Mattijssen, Cilia Witteman, Charles Berger, Xiaoyu A. Zheng, Johannes A. Soons, Reinoud Stoel
Forensic firearm examination provides the court of law with information about the source of fired cartridge cases. We assessed the validity of source decisions

Index of refraction of germanium

John H. Burnett, Eric C. Benck, Simon G. Kaplan, Erik Stover, Adam Phenis
Measurements of the index of refraction of a sample of high-quality, single-crystal germanium using the minimum deviation refractometry method are presented for


Group Leader

General Information