标题：Absolute calibration of the spectral responsivity of thermal detectors in the near-infrared (NIR) and mid-infrared (MIR) regions by using blackbody radiation
摘要：Abstract. The Physikalisch-Technische Bundesanstalt (PTB) has set up an additional measurement approachfor the absolute calibration of the spectral responsivity of detectors in the near-infrared (NIR) and mid-infrared(MIR) spectral range. This alternative method uses the radiation of a blackbody operating at about 1200 K witha precision aperture. The blackbody radiation can be calculated by Planck’s law and is additionally spectrallyselected by accurately characterized optical bandpass filters. Thus, a calibration of the spectral responsivity of adetector with respect to irradiance can be achieved at the bandpass wavelength of the applied transmission filters.If the aperture of the detector is known, the spectral responsivity can also be calculated with respect to radiantpower.Thermopile detectors with known aperture size were calibrated in terms of their spectral responsivity withseveral bandpass filters in the spectral range between 1.5 µm up to 14 µm with relative standard measurementuncertainties between 5 % and 19 %. The obtained results are consistent with previous calibrations at PTB’snational primary detector standard. Therefore, this additional measurement approach is a further validation ofthe existing primary method which is based on a cryogenic radiometer and extends the usable wavelength range.
