Abstract

Subject of study. Plasma emitters generating high-power light pulses of a second duration, an open discharge of an erosion type controlled by a magnetic field, a magnetically pressed discharge, and a large-format lamp panel based on tube gas-discharge lamps are studied. Aim of study. This study attempts to develop a methodology for measuring the absolute values of the spectral density of radiance of these sources using a spectrometer of the USB4000 type. Research method. The measurement procedure includes measuring the light pulse with a pyroelectric detector (or calorimeter) installed at a certain distance from the radiation source, determining the irradiance and integrated luminance in the selected spectral interval and registering the source spectrum. Then, the measured spectral dependence is adjusted for the spectrometer sensitivity and the exposure time to obtain a value proportional to the spectral density of the radiance. The absolute values of the spectral density of the radiance of the source are determined by integrating the found dependence in Excel in a graphic form with due regard for integrated luminance in the selected spectral interval. Main results. The technique of absolute radiometric calibration of the USB4000 spectrometer has been developed and applied, which makes it possible to increase the accuracy and reliability of the results obtained with simultaneous expansion of the spectral range from 220 to 900 nm. The technique is based on the use of two mutually complementary certified radiation sources with different spectral compositions. To measure the spectral density of the radiance of the radiation sources, the measurement scheme based on the pre-calibrated USB4000 spectrometer is supplemented with a calorimeter (or a non-selective pyroelectric receiver) with band-pass light filters to find the irradiance in the selected spectral interval. The absolute values of the spectral density of the radiance of the magnetically pressed discharge radiation in the spectral range of 220–400 nm and lamp panel in the range of 400–900 nm are determined. Practical significance. Absolute calibration of spectrometers in the visible and infrared spectral regions presents no special problem owing to the availability of standardized calibrated radiation sources. In the ultraviolet range, this is the problem for the lack of adequate equipment. The developed method makes it possible to obtain absolute values of the spectral density of radiance of plasma sources in the ultraviolet range of the spectrum as well.

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