Abstract
The Low-Background Infrared (LBIR) calibration facility at NIST provides customers in the missile defense community and others with measurements of radiance temperature and infrared irradiance in a low-background vacuum environment that are traceable to the national primary standard for optical power. Traceability can be established through radiance temperature measurements of users’ cryogenic blackbody sources at NIST, or by measurements of the irradiance output of cryogenic vacuum infrared test chambers by the LBIR transfer radiometers, BXR and MDXR, in the 3 µm to 28 µm wavelength region. We discuss the status and recent developments in both of these primary calibration areas, including the construction of a new fluid-bath cryogenic blackbody source for radiance and irradiance calibrations. In addition, LBIR is working with others at NIST and in the infrared calibration community to develop new traceability paths for low-level spectral irradiance and power. These development efforts include spectrally calibrated Si:As trap detectors, compact electrical substitution radiometers based on carbon nanotube absorbers, and new capabilities to calibrate users’ cryogenic transfer radiometers at NIST.
Status of Low-Background Infrared Calibration Facility at NIST
The Low-Background Infrared (LBIR) calibration facility at NIST provides customers in the missile defense community and others with measurements of radiance temperature and infrared irradiance in a low-background vacuum environment that are traceable to the national primary standard for optical power. Traceability can be established through radiance temperature measurements of users’ cryogenic blackbody sources at NIST, or by measurements of the irradiance output of cryogenic vacuum infrared test chambers by the LBIR transfer radiometers, BXR and MDXR, in the 3 µm to 28 µm wavelength region. We discuss the status and recent developments in both of these primary calibration areas, including the construction of a new fluid-bath cryogenic blackbody source for radiance and irradiance calibrations. In addition, LBIR is working with others at NIST and in the infrared calibration community to develop new traceability paths for low-level spectral irradiance and power. These development efforts include spectrally calibrated Si:As trap detectors, compact electrical substitution radiometers based on carbon nanotube absorbers, and new capabilities to calibrate users’ cryogenic transfer radiometers at NIST.