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Search Publications by: Thomas C Larason (Fed)

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Displaying 26 - 50 of 53

Extension of the NIST tristimulus colorimeter for solid-state light source measurements

May 29, 2009
Author(s)
George P. Eppeldauer, Carl C. Miller, Thomas C. Larason, Yoshihiro Ohno
In order to obtain improved color measurement uncertainties for solid state light (SSL) sources, the second generation tristimulus colorimeter of NIST has been extended with a fifth channel to perform efficient matrix corrections for the spectral mismatch

Calibration and Characterization of UV Sensors for Water Disinfection

January 2, 2006
Author(s)
Thomas C. Larason, Yoshihiro Ohno
Ultraviolet radiation (UV) effectively inactivates common pathogens found in ground and surface waters such as Cryptosporidium, Giardia, and most bacterial pathogens (e. g., E. coli). Water treatment facilities recently started using ultraviolet radiation

Calibration and Standardization Issues of UV Sensors for Water Disinfection

August 1, 2005
Author(s)
Thomas C. Larason, Yoshihiro Ohno
Ultraviolet radiation (UV) effectively inactivates common pathogens found in ground and surface waters such as Cryptosporidium, Giardia and most bacterial pathogens. Water treatment facilities recently started using ultraviolet radiation for disinfection

Characterization of UV Detectors at SURF III (invited)

March 1, 2002
Author(s)
Ping-Shine Shaw, Thomas C. Larason, R Gupta, Keith R. Lykke
The Synchrotron Ultraviolet Radiation Facility (SURF III) at the National Institute of Standards and Technology provides a unique research opportunity in precision measurement with its continuous and calculable radiation stretching from the soft x-ray to

Method of Measuring Shunt Resistance of Photodiodes

January 1, 2001
Author(s)
P R. Thompson, Thomas C. Larason
A method of measuring the shunt resistance of diodes, specifically photodiodes, is examined and the procedure of how the method is implemented using LabVIEW is detailed. Rudimentary comparison with other accepted methods in industry is done. The

Sources of Uncertainty in UV Radiation Measurements

January 1, 2001
Author(s)
Thomas C. Larason, Christopher L. Cromer
Increasing commercial, scientific, and technical applications involving ultraviolet (UV) radiation has led to the demand for improved understanding of the performance of instrumentaion used to measure this radiation. There has been an effort by

Improved Near-Infrared Spectral Responsivity Scale

September 1, 2000
Author(s)
Ping-Shine Shaw, Thomas C. Larason, R Gupta, Steven W. Brown, Keith R. Lykke
A cryogenic radiometer-based system was constructed at the National Institute of Standards and Technology (NIST) for absolute radiometric measurements to improve detector spectral responsivity scales in the wavelength range from 900 nm to 1800 nm. In

Optical Characterization of Diffuser-Input Standard Irradiance Meters

September 1, 1998
Author(s)
George P. Eppeldauer, M Racz, Thomas C. Larason
Standard quality irradiance meters have been developed at the National Institute of Standards and Technology (NIST) to realize detector based spectral irradiance scale. The design criteria and the optical and radiometric characterization of diffuser-input