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Thomas C Larason

Mr. Thomas Larason is an Electronics Engineer in the Sensor Science Division at the National Institute of Standards and Technology (commonly referred to as NIST). His career at NIST began in 1989 where his research has focused on detectors of ultraviolet, visible, and near infrared light. Additional research areas include the measurement of photocurrent, aperture area, and developing new transfer standards. He has collaborated with both university and industry researchers on various projects including UV light sensors used for the inactivation of pathogens for drinking water and remote sensing.

Mr. Larason is active in several international committees for optical radiation measurement. He is a member of CIE TC2-29 Measurement of Detector Linearity and CIE TC2-47 Characterization and Calibration Methods of UV Radiometers committees.

He is also a co-recipient in 1995 of the Department of Commerce Bronze Medal Award for Superior Federal Service in developing and documenting a quality system compliant with ISO Guide 25 for the NIST Optical Technology Division.

Research Projects:

Detector metrology
Spectral responsivity measurement
Broadband UV measurement
Sensors for UV inactivation of microbes
Photocurrent measurement
Aperture area measurement
Remote sensing laboratory


Gain Calibration of Current-to-Voltage Converters

Thomas C. Larason, Carl C. Miller
Current-to-voltage converters are used in many photometric and radiometric applications. The calibration of current- to-voltage converters at a few input

Standardization of UV LED measurements

George P. Eppeldauer, Thomas C. Larason, Howard W. Yoon
Traditionally used source spectral-distribution or detector spectral-response based standards cannot be applied for accurate UV LED measurements. Since the CIE
Created October 9, 2019