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Leonard Hanssen (Fed)

Leonard Hanssen is Project Leader for Infrared Spectrophotometry, and is responsible for the development and maintenance of NIST's scales for infrared spectral transmittance (τ), reflectance (ρ), and emittance (ε) of materials. His interests include the design and development of high accuracy measurement instrumentation, as well as the evaluation and optimization of absolute measurement methods, for τ, ρ and ε characterization. Of special interest are the theory, modeling, design, and application of integrating spheres; primarily for reflectance measurements, but also for creation of uniform Lambertian sources, and uniform detectors. Within the division, he is also involved in infrared spectral radiance and radiance temperature metrology as well as infrared detector metrology. In relation to this work, he also participates in the development of international standards.

He is a fellow member of the SPIE, the international Society for optics and photonics. He is also a member of the Council for Optical Radiation Measurements (CORM), the ASTM International, the American Geophysical Union (AGU), the US Technical Advisory Group (TAG) to the International Standards Organization (ISO) Technical Committee on Optics and Photonics (TC-172), and the US National Committee of the International Commission on Illumination (CIE-USNC).

He is the recipient of the Arthur S. Flemming Award for extraordinary contributions to the federal government in Applied Science (2002), the Department of Commerce Silver Medal Award (2007), the NIST Judson C. French Award (2009), and the Department of Commerce Gold Medal Award (2013).

Publications

Methods for Quantitative Infrared Directional-Hemispherical and Diffuse Reflectance Measurements Using a Fourier Transform Spectrometer and a Commercial Integrating Sphere

Author(s)
Leonard M. Hanssen, Thomas A. Blake, TImothy J. Johnson, Russell G. Tonkyn, Brenda M. Forland, Tanya L. Myers, Carolyn S. Brauer, Yin-Fong Su, Bruce E. Bernacki
Infrared integrating sphere measurements of solid samples are important in providing reference data for contact, standoff and remote sensing applications. At
Created October 9, 2019, Updated June 15, 2021