A continuously emitting electric discharge UV lamp

Abstract

A UV lamp pumped by a dc-current glow discharge in a mixture of helium with iodine vapors inside a quartz discharge tube with an interelectrode distance of 50 cm is described. For the power deposited in discharge (Wel ≤ 200 W), the total power emitted by the lamp in the spectral range 200–350 nm is as high as 27 W with an efficiency of ≤18 %. The lamp service life in the gas-static mode is 400–500 h. The emission is distributed almost equally between the spectral line of iodine atoms λ = 206.2 nm) 0.12 nm wide and the electron vibrational bands of I2(B-X) molecules λmax = 342 nm). The optimal helium partial pressure is 600–800 Pa.