Cryogenic Radiometer Measurement Characteristics Of The Measuring Device And Method Of Value Transfer

Cryogenic Absolute Radiometer(CAR), as the most accurate radiation measurement technique now, has become the research focus of many national metrology institutes.Trap detector with it's excellent characters has been used as the bridge of quantity chain in CAR system. The parameters of trap detectors including: spatial uniformity, polarization dependence, angular variation, temperature coefficient, have effect on quantity transfer process, so these effect are quantificationally discussed on the basis of a series of special experiments.Some peripheral experiment and analysis about CAR have been performed, include: laser beam preparation and it's adjustment, Laser Power Controller and our achievement on improving it's performance, the measurement of transmittance of Brewster window, CAR cavity absorptance measurement.Using the new CAR system software, many inherent characters of CAR have been analyzed, then some parameter setting during CAR experiment are given much more reasonably. Using the virtual radiation method, the performance of the whole CAR system has been analyzed.On the basis of analysis and experiments above, the quantity transfer from CAR to other detectors have been performed using trap detector and the uncertainty of the transfer process is analyzed.