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Benjamin K. Tsai

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, in the Sensor Science Division, he serves as the Computer Security Officer, Property Custodian, and Web Site Coordinator. Currently, his research has focused on photometry.

Dr. Tsai has just finished co-editing 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. Recently, he has finished co-editing a volume, entitled "Spectrophotometry: Accurate Measurement of Optical Properties of Materials" for the same series. He is a co-organizer and lecturer for the Spectroradiometry and Spectrophotometry Short Courses, which run every two years.

Research Projects:




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