Calibration of broadband ultraviolet detectors by measurement of spectral irradiance responsivity

Abstract

We have developed and characterized a measurement setup for measuring the spectral irradiance responsivity s͑͒ of broadband UV detectors. The setup consists of a single grating monochromator and a powerful ͑450 W͒ Xe source to maximize the output power and thus enable spectral measurements with broadband detectors, whose sensitivity is typically low. Commercial UVA and UVB detectors were characterized with the setup. The results of the UVA detector were verified with a spectroradiometric calibration, and the results of the two methods agreed within 1.2%. The uncertainties ͑coverage factor k =2͒ were 2.0% ͓method utilizing s͔͑͒ and 3.1% ͑spectroradiometric method͒. Also the applicability of a correction factor for transforming calibration results between light sources was tested, and the obtained correction agreed with measurement results.FIG. 6. The measured s͑͒ of the UVB detector. The vertical lines denote the limits of the UVB region ͑280-315 nm͒. 063110-5Calibration of broadband detectors Rev. Sci. Instrum. 77, 063110 ͑2006͒