Radial characteristics of radiation of high-frequency electrodeless lamps

Abstract

The radial dependences of the radiative characteristics of high-frequency electrodeless lamps (HFELs) using as a working medium either a mixture of mercury and argon or helium have been investigated in experiments and numerical simulations. The intensities of the mercury line at a wavelength of 546.1 nm and the helium line at 587.6 nm have been measured. The measurements were conducted at different points lying on the central chord of the circular end of a cylindrical lamp. As the power of the pumping generator increases, a decrease in the radiation intensity near the axis of the discharge in a mercury vapor HFEL is observed, while, in the helium lamp, on the contrary, the intensity increases. On the basis of models of HFELs developed earlier, we have calculated the radial dependences of the radiation intensity of the mercury line at 546.1 nm and the helium line at 587.6 nm. A satisfactory agreement with the data of experimental measurements has been attained. A comparative analysis has been carried out, and an explanation has been proposed for the difference in the observed radial intensity profiles of these two lines.