HIGH-FREQUENCY DISCHARGE-LAMP WITH HOLLOW ELECTRODE

A new spectral-line source, which is a high-frequency discharge-lamp with a hollow electrode, is described. The lamp is designed for efficient operation using only high-frequency power. Absolute radiance of the high-frequency lamp is measured at operating frequencies of 20 and 85 MHz, at power levels of 2 to 30 W, and in the pressure range from 1 to 8 torr. The radiance of the high-frequency lamp is ten to a hundred times higher than that of hollow-cathode lamps under d.c. operation at maximum rating. The S/N ratio in element analysis utilizing coherent forward-scattering of resonance radiation is improved by the high-frequency lamp. The width of the spectral line emitted from the high-frequency lamp is comparable with that of the d.c. hollow-cathode lamp. © 1979.