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Benjamin K. Tsai (Fed)

Dr. Benjamin Tsai is a physical scientist in the Sensor Science Division at the National Institute of Standards and Technology. Since his career at NIST began in 1993, his research interests have included radiation thermometry, heat flux, rapid thermal processing, and spectrophotometry. From 2006 to 2007, he served as the NIST Quality System Coordinator. Now, he serves as the division Property Custodian, a computer security representative, and a PML SHIP Director. Currently, his research has focused on solid state lighting and its Measurement Assurance Program.

Dr. Tsai co-edited a two-volume authoritative reference on radiation thermometry, entitled "Radiometric Temperature Measurements: I. Fundamentals" and "Radiometric Temperature Measurements: II. Applications." The two volumes are Volume 42 and Volume 43 of the series, "Experimental Methods in the Physical Sciences," edited by the treatise editors, Albert C. Parr and Thomas Lucatorto. He has also co-edited Volume 46, entitled "Spectrophotometry: Accurate Measurement of Optical Properties of Materials" for the same series. He is a co-organizer and lecturer for the Spectroradiometry, Spectrophotometry, and Photometry Short Courses, which run every two years.

Research Projects



2018 NIST Bronze Award "for the establishment of an accurate database of human skin reflectance measurements for wavelengths ranging from the shortwave infrared to the ultraviolet spectral region."


Recent research and development in photometry at NIST

Yuqin Zong, Maria Nadal, Benjamin K. Tsai, C Cameron Miller
Many developments were made in recent years in photometry at NIST for reducing measurement uncertainties, increasing calibration efficiencies, and adding

Exposure Study on the Aging of PTFE and Ceramic Diffusers

Benjamin K. Tsai, Catherine C. Cooksey, David W. Allen, Christopher C. White, Walter E. Byrd, Deborah S. Jacobs
This paper describes efforts to quantify the effects of aging in the ultraviolet (UV) on polytetrafluoroethylene (PTFE) and ceramic samples. Long term UV aging

NIST Measurement Services: Photometric Calibrations

Carl C. Miller, Maria E. Nadal, Benjamin K. Tsai, Yuqin Zong
The National Institute of Standards and Technology provides calibration services for submitted artifacts for luminous intensity, illuminance, color temperature

Reference Data Set of Human Skin Reflectance

Catherine C. Cooksey, David W. Allen, Benjamin K. Tsai
This data set contains 100 reference reflectance spectra of human skin, spanning the wavelength region from 250 nm to 2500 nm. The spectra were acquired with a
Created October 9, 2019, Updated December 8, 2022