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AC-Mode SW-IR Radiation Thermometers for Measurement of Ambient Temperatures



George P. Eppeldauer, Howard W. Yoon


Recent improvements in the fabrication technology of short-wave infrared (SWIR) quantum detectors opened a new era in radiation thermometry. Ambient and higher temperatures can be measured with low uncertainties using thermoelectrically (TE) cooled extended-InGaAs (E-IGA) and short-wave photovoltaic-HgCdTe (sw-MCT) detectors. These detectors, because of their low (2.5 ?m and 2.8 ?m, respectively) cut-off wavelengths, have orders of magnitude lower background noise than traditionally used broad-band infrared detectors such as cryogenically cooled, quantum detectors or thermal detectors. Because of the low detector cut-off wavelength, traditional glass-based optics can be used in the radiation thermometers. To measure low temperatures, the signal measured should be in alternating-current (AC), modulated or chopped, mode to separate it from the background-radiation-produced direct-current (DC) signal and its fluctuations. Design considerations and characteristics of a newly developed SWIR radiation thermometer are discussed. A noise-equivalent temperature difference (NETD) of
Proceedings Title
TEMPMEKO Conference | 2007 |
Conference Dates
May 21-25, 2007
Conference Location
Chateau lake Louise, CA
Conference Title


ambient temperatures, infrared, input optics, NEP, NETD, noise, optical radiation, radiance, radiation thermometer


Eppeldauer, G. and Yoon, H. (2007), AC-Mode SW-IR Radiation Thermometers for Measurement of Ambient Temperatures, TEMPMEKO Conference | 2007 |, Chateau lake Louise, CA (Accessed December 4, 2023)
Created May 25, 2007, Updated June 14, 2017