Temperature standard for radiometric calibration of earth-observation sensor

The earth-observing hyperspectral imager, HISUI (Hyper-spectral Imager SUIte), which is currently under development, has a wide spectral range from 0.4 μm to 2.5 μm, and the radiance of the copper point is insufficient for sensor calibration in the wavelength range shorter than 0.55 μm. This is in contrast to the predecessor sensor (ASTER), whose shortest band is 0.56 μm. To cover the short wavelength range, we have developed large-aperture cells of high-temperature fixed points (HTFPs) of cobalt-carbon (Co-C, 1324 °C), platinum-carbon (Pt-C, 1738 °C) and rutheniumcarbon (Ru-C, 1953 °C) eutectic systems. The calibration result, uncertainty and validation method will be presented.