DETECTOR-BASED CALIBRATION METHOD FOR HIGH-ACCURACY SOLAR UV MEASUREMENTS

A novel method for calibrating the absolute responsivity of solar UV s pectroradiometers has been developed and tested, The method is based o n calibrated filter radiometers constructed from a detector, a precisi on aperture, a band-pass filter and devices for temperature stabilizat ion. The filter radiometers utilize a trap detector with very low refl ectance. The filter and the detector can therefore be characterized se parately, As an example the detector-based calibration is compared at 312 nm wavelength with lamp-based calibration by measuring the irradia nce of a deuterium lamp with both the filter radiometer and the lamp-c alibrated spectroradiometer. The agreement between the results is at t he level of 1%, well within the estimated uncertainties of both method s.